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Carl@Semroc
01-09-2011, 01:39 PM
I have added an online engine survey to get you input. This is in a constant state of change. As more engines are better characterized, the data will be updated. I will be adding some links to .eng files for Rocksim as I get them completed.

The engines longer than 3.25" are in the future, since they will require a new machine, but we do want to get an idea of interest in current sizes, as well as future sizes.

This survey is only for SAM's until we are ready for a larger public exposure. Please send your comments, errors, omissions, ideas, etc. in this thread. We want all SAM's to have as much input in this process as possible.

The link is Engine Survey (http://www.semroc.com/Store/Scripts/enginesurvey.asp). You have to login to see it. There is a current limit of 100 packs per engine so the results do not get badly skewed. (GH... don't break the B14 buttons! :chuckle: )

Ltvscout
01-09-2011, 02:48 PM
Whoa! That list is dizzyingly (is that a word?) long!

I'll just answer, yes. :D

CPMcGraw
01-09-2011, 02:56 PM
Carl,

Are these based on the thrust curves we 'discussed' and even designed a few possible models around over on the SVDT? I'll have to dig out my old engine files...

SEL
01-09-2011, 03:01 PM
Ok, I filled out the form, but I didn't see a 'save' button.
Does it automatically save it under my SAM No.?

S.

I have added an online engine survey to get you input. This is in a constant state of change. As more engines are better characterized, the data will be updated. I will be adding some links to .eng files for Rocksim as I get them completed.

The engines longer than 3.25" are in the future, since they will require a new machine, but we do want to get an idea of interest in current sizes, as well as future sizes.

This survey is only for SAM's until we are ready for a larger public exposure. Please send your comments, errors, omissions, ideas, etc. in this thread. We want all SAM's to have as much input in this process as possible.

The link is Engine Survey (http://www.semroc.com/Store/Scripts/enginesurvey.asp). You have to login to see it. There is a current limit of 100 packs per engine so the results do not get badly skewed. (GH... don't break the B14 buttons! :chuckle: )

Carl@Semroc
01-09-2011, 03:11 PM
Carl,

Are these based on the thrust curves we 'discussed' and even designed a few possible models around over on the SVDT? I'll have to dig out my old engine files...
They are similar, but I have some that are projections (like we did) and some are actual. Since the ID of the Standard increased to .520", they are slightly higher. The 10mm is characterized, but the 15 and 22 are not.

BEC
01-09-2011, 03:12 PM
I agree with Scott....it's hard to wrap one's mind around such a large and varied list.

Some curiosities:

It seems that (for now) all the weights are propellant + 1g regardless of form factor or delay. I expect that's a work-in-progress kind of thing.

Also, in the "retro" section there are "R" and "RS" entries. The "RS" types are really shorties, right?

Finally, the motor designations that are in small type and parentheses are the Estes designations for the same motors, right? In the case of the "retros" they're the pre-metric designations.

Carl@Semroc
01-09-2011, 03:23 PM
Ok, I filled out the form, but I didn't see a 'save' button.
Does it automatically save it under my SAM No.?

S.
After entering a quantity, either hit enter or the update button beside the number. It is going to a database, so the information is stored immediately. The last column combines your count with all the others entered, realtime. If you change an amount, it does not add or subtract, but replaces the previous quantity for that engine.

I put this online before all the wrinkles are out, so please be patient with me! :o

Carl@Semroc
01-09-2011, 03:31 PM
I agree with Scott....it's hard to wrap one's mind around such a large and varied list.

Some curiosities:

It seems that (for now) all the weights are propellant + 1g regardless of form factor or delay. I expect that's a work-in-progress kind of thing.

Also, in the "retro" section there are "R" and "RS" entries. The "RS" types are really shorties, right?

Finally, the motor designations that are in small type and parentheses are the Estes designations for the same motors, right? In the case of the "retros" they're the pre-metric designations.
You can understand the magnitude of this. I want two machines to do all 200 or so of the engines with very little changeover between types.

The S and RS are shorties. The R designates the Mabel I (.406") ID with thick walls.

I am working on the Initial weight. For now it does just add 1 g. That will change to reflect the real weight.

Pyro Pro
01-09-2011, 03:43 PM
Would it be difficult to have a general "Update All" button that will check all the form selections? It would be a little easier than individually clicking each one, but it isn't a big issue. Such an enticing list...

GeoLaw
01-09-2011, 03:48 PM
If one is "logged on" as a SAM through the Semroc website, is there another step in being able to see the engine survey? How does one go about

John

Carl@Semroc
01-09-2011, 03:51 PM
Would it be difficult to have a general "Update All" button that will check all the form selections? It would be a little easier than individually clicking each one, but it isn't a big issue. Such an enticing list...
I was going to do that, but it is slower and required another ASP page. I have that on my list.

Missed you during the holidays!

Carl@Semroc
01-09-2011, 03:52 PM
If one is "logged on" as a SAM through the Semroc website, is there another step in being able to see the engine survey? How does one go about

John
I am working on that. I think it is a session cookie thing. It works on mine, but not on Sheryl's. :confused:

SEL
01-09-2011, 03:56 PM
After entering a quantity, either hit enter or the update button beside the number. It is going to a database, so the information is stored immediately. The last column combines your count with all the others entered, realtime. If you change an amount, it does not add or subtract, but replaces the previous quantity for that engine.

I put this online before all the wrinkles are out, so please be patient with me! :o
Not a problem, I should have paid a little more attention. At any rate, the only real problem is that there are too many on the list that I'd take 10 packs of right off the top if I could afford to. I'm keeping my initial choices to the motors that aren't available anywhere else, and trying to be realistic about the quantities.

S.

kurth
01-09-2011, 04:14 PM
I took the survey. All I can say is WOW

It would be fun to be able to try many of those. Good luck on this endeavor.

tbzep
01-09-2011, 04:14 PM
I don't know if I can afford what I chose, but I'd sure like to give it a shot. :cool:

DaveR
01-09-2011, 04:22 PM
I've completed the survey trying to be realistic as possible but I tend to agree with zep above, don't know if I can afford what I chose....... :o

tbzep
01-09-2011, 04:31 PM
Mine looked really good at first, then I realized it is "packs" instead of "motors". 15 packs of any of the special use motors is quite a lot!

Carl@Semroc
01-09-2011, 04:51 PM
Mine looked really good at first, then I realized it is "packs" instead of "motors". 15 packs of any of the special use motors is quite a lot!
You can correct them by changing the quantities.

Doug Sams
01-09-2011, 04:53 PM
I'm keeping my initial choices to the motors that aren't available anywhere else, and trying to be realistic about the quantities.Same here. Even then I doubt I could burn all I selected in one year. Which means, I probably couldn't /wouldn't buy that many the next year (despite liking to think otherwise :))

Doug

.

blackshire
01-09-2011, 05:32 PM
The link is Engine Survey (http://www.semroc.com/Store/Scripts/enginesurvey.asp). You have to login to see it. There is a current limit of 100 packs per engine so the results do not get badly skewed. (GH... don't break the B14 buttons! :chuckle: )When I clicked on the link, all I got was a blank white screen with the words "Must be logged on as a SAM!"...which I don't know how to do even though I am one.

BEC
01-09-2011, 06:15 PM
When I got that all I had to do was log in into my Semroc account in another tab of my browser (which gave me the "welcome back" message) then click on the survey. Try that....

blackshire
01-09-2011, 06:49 PM
When I got that all I had to do was log in into my Semroc account in another tab of my browser (which gave me the "welcome back" message) then click on the survey. Try that....Thank you very much--that did the trick!

blackshire
01-09-2011, 07:16 PM
Well, I don't know if they "took" or not (I hit "update" after each motor packs quantity entry), but I filled out the motor survey. One suggestion, Carl: If you could post the original 1968 - 1971 Semroc "Recommended Propulsion Modules" lists for the Semroc kits of that era, it would help us select among your unusual motor types ("3/4A," "3/4B," etc.) for use in your "Retro-Repro" Semroc Swift, Aphelion, Lune R-1, Goliath, etc.

Carl@Semroc
01-09-2011, 07:24 PM
Well, I don't know if they "took" or not (I hit "update" after each motor packs quantity entry), but I filled out the motor survey. One suggestion, Carl: If you could post the original 1968 - 1971 Semroc "Recommended Propulsion Modules" lists for the Semroc kits of that era, it would help us select among your unusual motor types ("3/4A," "3/4B," etc.) for use in your "Retro-Repro" Semroc Swift, Aphelion, Lune R-1, Goliath, etc.
I cannot find that list. As soon as I get the RockSim engine files, I can run a matrix with all our current kits.

blackshire
01-09-2011, 07:32 PM
I cannot find that list. As soon as I get the RockSim engine files, I can run a matrix with all our current kits.Thank you! I see great potential in those "fractional impulse category" motors as being "tailor-to-field" and "tailor-to-model" (especially multi-stage models) motors. In situations where a given field is a bit too small or a model is a bit too light for recovery on the field to be likely with a full "A," "B," or "C" motor, the "3/4" and other fractional motors could fill the gaps without being *too* powerful.

AstronMike
01-09-2011, 11:07 PM
The ones I like are the A3-2T along with the mini B3-3 motors. I love the C5-3 but did not 'choose' it just yet, but if that ever came back, I would definitely be getting those.

Also seen what looked like 'your' version 20mm D5 motor and picked that.

Plenty of others there as well, but only a few of them I would really want as a mainstream motor choice.

BEC
01-10-2011, 01:30 AM
I'm with Jason and others.... I focused on choices that are not available from E or Q, and tailoring to sites. I didn't know quite what to do with some of the new-to-me sizes including the "Wide" ones that appear to use ST-8 as the motor tube and the 15mm or 10mm choices. It's sort of a chicken/egg thing for me there.

That you're even considering this is quite exciting news for me. Thanks!

blackshire
01-10-2011, 05:33 AM
I'm with Jason and others.... I focused on choices that are not available from E or Q, and tailoring to sites. I didn't know quite what to do with some of the new-to-me sizes including the "Wide" ones that appear to use ST-8 as the motor tube and the 15mm or 10mm choices. It's sort of a chicken/egg thing for me there.I didn't even *touch* the "Wide," 10 mm, and 15 mm motor choices, but *NOT* for lack of interest in them! I was just so overwhelmed (happily so!) with the other, more familiar choices that I concentrated on them.

The 10 mm and 15 mm categories in particular could re-invigorate FAI contest flying (I know British FAI flyers who would love to be able to buy such motors), and these motors would also be useful for urban and small-field sport flying (a "bridge" between the 6 mm MicroMaxx motors and the 13 mm mini motors). The new Q2-type igniters would make even the 10 mm and 15 mm motors easy to prep, with reliable ignition.That you're even considering this is quite exciting news for me. Thanks!Maybe if all of us who are club members spread the word about this, we could help create a receptive "market-in-waiting" among model rocket clubs, NAR sections, schools, Scouts, and 4-H Clubs (not by *promising* them new Semroc motors, but by encouraging them to compile "preferred motor lists" and submit them to Semroc to give them ideas of where they could most profitably concentrate their motor development efforts).

tbzep
01-10-2011, 08:12 AM
Maybe if all of us who are club members spread the word about this,
Nothing posted here is supposed to be mentioned outside the SAM forum! :eek:


.

blackshire
01-10-2011, 08:44 AM
Nothing posted here is supposed to be mentioned outside the SAM forum! :eek:


.No harm done, then. I haven't said anything to anyone else and won't.

tbzep
01-10-2011, 09:09 AM
No harm done, then. I haven't said anything to anyone else and won't.

If you mentioned it to the club, your words would probably freeze and fall to the ground up there in Alaska/Siberia anyway. :D :chuckle:

Chas Russell
01-10-2011, 09:13 AM
I could not get into the survey even though I had logged in with the SAM site. I think it is this old computer, so I will try later on my wife's computer. It is great to be asked for input.

Carl, what is your thinking about starting with motors that are offered by E and Q to establish your products as opposed to offering motors people really want? I fully realize that motors designed for competition are a very limited market.

Chas

tbzep
01-10-2011, 09:33 AM
I could not get into the survey even though I had logged in with the SAM site. I think it is this old computer, so I will try later on my wife's computer. It is great to be asked for input.

Carl, what is your thinking about starting with motors that are offered by E and Q to establish your products as opposed to offering motors people really want? I fully realize that motors designed for competition are a very limited market.

Chas

I was able to go to it by logging in to the SEMROC website, making sure it showed the "Welcome Back Tim - SAM member # 0069" under the top banner. I kept that tab open and went to the survey site in a second tab. I'm running Firefox on Linux. Most of my security settings are at low to mid level.

Chas Russell
01-10-2011, 10:18 AM
Thanks tbzep. I did have my SAM number showing, but after I clicked on the SAM explaination on the right side, then I was able to get in and take the survey.

Chas

Carl@Semroc
01-10-2011, 11:37 AM
I could not get into the survey even though I had logged in with the SAM site. I think it is this old computer, so I will try later on my wife's computer. It is great to be asked for input.

Carl, what is your thinking about starting with motors that are offered by E and Q to establish your products as opposed to offering motors people really want? I fully realize that motors designed for competition are a very limited market.

Chas
We will have to. When you have 100 kits that take a particular mix of engines, it would be a shame to not be able to provide engines for your own kits. They will be different becaue the C5 will really be a C5 with a 22 N peak for many kits we cannot do. The B8 will also be in the same 18x70HB family. The B14 and 3/4C19 will really allow 3 stage and heavier 2 stage 18mm models.

The Retro Mabel I family is one that will work with many of the oldest kits, since they are the engines that they were designed around. They do not match up with current NAR/FAI impulse ranges so they will not be useful for contests. I have them in the queue just for fun. They had a softer/longer burn than the later Mabel II types. I personally want to fly a few of them again.

CPMcGraw
01-10-2011, 02:38 PM
Carl, do you plan to post a (reasonably-close) RSE file soon for any of these? I'm not as familiar with the performance of the older engines as some of these guys, so I'm working blind trying to interpret how any given engine is going to respond.

blackshire
01-10-2011, 03:35 PM
We will have to. When you have 100 kits that take a particular mix of engines, it would be a shame to not be able to provide engines for your own kits. They will be different becaue the C5 will really be a C5 with a 22 N peak for many kits we cannot do. The B8 will also be in the same 18x70HB family. The B14 and 3/4C19 will really allow 3 stage and heavier 2 stage 18mm models.

The Retro Mabel I family is one that will work with many of the oldest kits, since they are the engines that they were designed around. They do not match up with current NAR/FAI impulse ranges so they will not be useful for contests. I have them in the queue just for fun. They had a softer/longer burn than the later Mabel II types. I personally want to fly a few of them again.The pre-metric A3-1 would be good for the AMROCS Hawk and Estes Falcon boost-gliders, and the Estes/Centuri Series III "Shorty" motors would be perfect for the Centuri Lil' Herc and the Estes Sprite.

CPMcGraw
01-10-2011, 04:14 PM
After playing with the RockSim engine editor, and seeing the 'tiny script' under the engine name on the page, I know the B5-4 is going to be at least one engine on my purchase list. This one gives me excellent Dv numbers for the "Night S.H.A.D.O.W." design I'm starting.

PaulK
01-10-2011, 10:55 PM
Very cool survey, though a bit overwhelming. While I'd like to use a number of different motors not currently available, there is overlap. I like to fly small multi stagers, and can adapt depending what is available. I like shorties to fly the old designs, but am perfectly ok with mini motors I can friction fit in 18mm casings to create my own shorties. So, while I entered small quantities for a number of such motors, if, for example, the only 1/2A booster is a 13mm, I'd purchase more of these, since I can make shorties. I'd really like some form of 18mm 1/2A6-4 - if it isn't a shorty, I can cut them down. I guess what I'm trying to say is, given fewer choices, the quantities would go up.

Flew a vintage A5-2S in a Sprite clone made from Semroc parts just yesterday!

BEC
01-11-2011, 01:01 AM
Flew a vintage A5-2S in a Sprite clone made from Semroc parts just yesterday!

I must have missed shorty As altogether. I only remember 1/4 and 1/2As. A5-xS motors were ones I also "voted" for in the survey.

ECayemberg
01-11-2011, 08:03 AM
Wow, exciting prospects! Engine survey complete! My stash of shorties is dwindling; I'd love to see them return as I built several rockets for shorties.

I'm most interested in motors that are a bit different than those currently available....mainly toward one or the other extreme: either long burn low thrust or short burn high thrust.

I'll go broke if even half of that list is released.

-Eric-

ghrocketman
01-11-2011, 12:03 PM
Carl,
Fear not, I will not BREAK the B14 buttons, but WILL exercise them well.
Honestly I figured you were probably the ONLY company that was willing to actually produce motors we are ASKING for.
Had a little hope for the "new" Estes, but they obviously are choosing to ignore what many ask for.
When you get up and running, I will order plenty.
If you produce even 1/3 of the 18mm ones listed, especially the high-thrust port-burners, I can't see myself ordering/buying 18mm BP motors from anyone else for a LOOOONGG time if ever.
I would have no use for the boring/vanilla offerings by "E" or "Q" any longer, and for 24mm and up I would probably just go 100% reloadable composite.

ghrocketman
01-12-2011, 09:39 AM
Carl-
Any plan as to when we may see a few samples of these new motors even experimentally ?
Personally I don't even care if they EVER get certified as that means NOTHING to me-just more un-needed BALONEY regulation.
- I would still fly them on my private land if I could get my hands on them-
GH

Carl@Semroc
01-12-2011, 09:46 AM
Carl-
Any plan as to when we may see a few samples of these new motors even experimentally ?
Personally I don't even care if they EVER get certified as that means NOTHING to me-just more un-needed BALONEY regulation.
- I would still fly them on my private land if I could get my hands on them-
GH
We cannot sell them or ship them without certification, governmental agency testing, EX-numbers, and USPS approval. :(

Ltvscout
01-12-2011, 10:07 AM
We cannot sell them or ship them without certification, governmental agency testing, EX-numbers, and USPS approval. :(
I guess we'll have to drive to NC then for beta testing pickup. :D

Carl@Semroc
01-12-2011, 10:43 AM
I guess we'll have to drive to NC then for beta testing pickup. :D
Is this one of those "if you build it, they (he) will come" things like the voice refered to in FOD? :D

ghrocketman
01-12-2011, 12:20 PM
I'd bet if you tranport them to NARAM and gave samples out to a select few for private evaluation at the end of the next NARAM you would get some feedback shortly afterward.
I'd like to see DE-regulation of BP motors the same way AP was via the lawsuit ruling vs BATFE.

tbzep
01-12-2011, 02:33 PM
I'd like to see DE-regulation of BP motors the same way AP was via the lawsuit ruling vs BATFE.

I would love to see it too, but it won't happen. APCP is not an explosive, but BP actually is a low explosive. I for one am thankful that Vern, G. Harry, Carlisle, or whoever deserves the credit, actually got the exemption so it could be shipped USPS and we've been able to keep it all these years.

Chas Russell
01-12-2011, 03:40 PM
ghrocketman said: "I'd bet if you tranport them to NARAM and gave samples out to a select few for private evaluation at the end of the next NARAM you would get some feedback shortly afterward."

Actually, SEMROC could demo the motors with S&T approval. At NARAM-11 FSI flew a modify E5 that had the separate charges and delays like the motor Carl mentioned early in this thread. I was there and it was interesting. I believe it was mentioned in the N11 coverage in Model Rocketry Magazine. Quest had a few D8 motors that were flown at the last NARAM.

I agree with Ltvscout, ROAD TRIP!

Chas

blackshire
01-12-2011, 03:42 PM
I would love to see it too, but it won't happen. APCP is not an explosive, but BP actually is a low explosive. I for one am thankful that Vern, G. Harry, Carlisle, or whoever deserves the credit, actually got the exemption so it could be shipped USPS and we've been able to keep it all these years.Now that the House of Representatives (as well as a significant fraction of the Senate) has changed hands, pushing for liberalization of the U.S. Postal System's regulations regarding shipping model rocket motors would be a good thing. It's ridiculous that it's kosher if the box has the correct "magic" sticker from a permit-holding shipper, yet it's "unsafe" if you or I or "Joe hobby shop owner" mails a box of motors. Marking a box "DOT Class C Toy Propellant Device" used to be good enough for anyone to mail motors, and there is no reason why it couldn't be again. Bringing up this issue to our legislators from the "angles" of creating more jobs by removing this barrier to business as well as the educational and social benefits of model rocketry (it keeps kids engaged and off the streets) should get their attention and interest.

billspad
01-13-2011, 06:15 AM
ghrocketman said: "I'd bet if you tranport them to NARAM and gave samples out to a select few for private evaluation at the end of the next NARAM you would get some feedback shortly afterward."

Actually, SEMROC could demo the motors with S&T approval. At NARAM-11 FSI flew a modify E5 that had the separate charges and delays like the motor Carl mentioned early in this thread. I was there and it was interesting. I believe it was mentioned in the N11 coverage in Model Rocketry Magazine. Quest had a few D8 motors that were flown at the last NARAM.

I agree with Ltvscout, ROAD TRIP!

Chas

He could but he'd better start now trying to get approval. Demo's have to be approved by the NAR President and he doesn't like them. I tried to get the NAR Board to change that so S & T could approve them (the way it used to be) and got shot down twice. Ironically, the only demo I can recall in the last twenty NARAM's was one that S & T refused to approve (it was a sparky on a dry field) and we got over ruled by Trip. It started a fire. The Quest D8's were certified before NARAM.

blackshire
01-13-2011, 06:50 AM
He could but he'd better start now trying to get approval. Demo's have to be approved by the NAR President and he doesn't like them. I tried to get the NAR Board to change that so S & T could approve them (the way it used to be) and got shot down twice. Ironically, the only demo I can recall in the last twenty NARAM's was one that S & T refused to approve (it was a sparky on a dry field) and we got over ruled by Trip. It started a fire. The Quest D8's were certified before NARAM.Well, fake Quest self-adhesive motor labels are pretty easy to print up at home... :-)

Solomoriah
01-13-2011, 08:01 AM
I don't know if I can afford what I chose, but I'd sure like to give it a shot. :cool:
Yeah, me too. :(

Chas Russell
02-03-2011, 12:23 PM
Carl,

Any updates for us minions? Also, what are your thoughts and plans for igniters?

Thanks,
Chas

Carl@Semroc
07-19-2011, 11:02 PM
The input here has been invaluable!

I have removed the Carlisle 13mm x 2.25" for now. Black Powder is just not as energetic as it was in the 60's. It is impossible to get a full 5 N-sec B engine with a delay in that package. I am concentrating on 15mm x 2.25" for the full B. I need to put some of the old MPC B3 engine on the stand. They probably were short as well. The Centuri A4-4 engines I tested were 1.7 N-sec with 2 second delay, so I tend to doubt some of the early documentation. Our goal is to call the engines what they are.

The 4.5" long engines were not as popular as I thought they would be, so they are gone from the survey as well. Since that length requires a whole new machine, the extra 8% in revenue (from the survey) would not be worth it until "Mabelette I" (christened by Vern) has made enough to pay for a sister. A long burn D has limited use anyway. The full E might justify it in the future since it would be just under the Estes E9 in average thrust, but have an even longer burn.

We have been doing most of our work fitting Mabelette for 10mm, but have all the parts to change over to 18mm made and tested. We hoped to have some samples of the 10mm to take to NARAM, but had to release new kits to keep a revenue stream instead. :( Plans are to do them first and have them for the FAI team to use for testing.

Even though the Retro (Mable I) engines are not popular, I will probably do them as anniversary specials or other special occasions, but they are also removed from the survey for now.

ghrocketman
07-21-2011, 10:19 AM
Carl,
PLEASE make the first run of 18mm motors B14's !!!!!!
I will gladly buy at least 10 packs of the first run.

How close are new 18mm motors to reality ?

jetlag
07-21-2011, 10:25 AM
and I'll buy the next 10+++!!!

Allen

BigRIJoe
07-27-2011, 05:16 AM
and put me down for the next 10!

mrhemi1971
07-27-2011, 02:29 PM
And just think, if you're a SAM + NAR you'll get them for 20% off!!

I'll go for a few packs too!

IMASAM 216

Carl@Semroc
09-27-2011, 03:11 PM
There are some new items on the Engine Survey page. Qualification testing on the Hybrid Port engines is complete and posted. Results for the 1/2A4, A7, 3/4B7, B7, 3/4C6, and C6 are given in a drawing and .eng files. The .eng files show slightly over the impulse limits on some of the engines. I did not stop to adjust the powder to keep all under the limits for impulse.
We are pleased with the results.

The hybrid port has a slightly deeper drill than standard to get the 18N peak. This is still not as high as the B14, B8, or C5 from the early days, but is higher than most engines in this class sold today. Now we have to decide whether to release the standard 11N peak as well as the hybrids or just release the hybrids and avoid the confusion.

A new .eng viewer is also included to analyze the results.

Feedback and comments are welcome!

ghrocketman
09-27-2011, 03:14 PM
Does this mean we will NOT be getting real B14's ??? :confused:

Carl@Semroc
09-27-2011, 04:08 PM
Does this mean we will NOT be getting real B14's ??? :confused:
No. They are in a different family. Working on them as time permits.

ghrocketman
09-28-2011, 10:10 AM
When in doubt, go with HIGHER thrust, not lower.
Release the 18N peak hybrids and forget the 11N others...you want to release something NOT already filled in the market, correct ?
The BP SU engine market is flooded with plenty of moderate and low thrust motors.
What I can't for the life of me figure out is who was asking for LOWER thrust long burn BP motors that have came on the market the past few years.
Where was the market research that suggested those were needed/wanted ?
I know I don't recall any threads asking for those, but there have been plenty asking for HIGH thrust motors.
Light rockets are the only ones that can use low-thrust motors without creating a menace.
High thrust motors can be used in light or heavy rockets, therefore the utility is FAR greater.
For example, it would have made FAR greater sense for "Brand E" to have brought out a port-burning D30 instead of the "cant lift a hill of beans" E9.
Please, no "screwball" non-standard motor diameters like 20mm or 27mm either.
Makes far more sense to make a slightly LONGER 18mm or 24mm motor to fit the propellant than some screwy 20 or 27mm design. I think most would rather have to add a little noseweight to compensate for a motor sticking a little out of the tail than have to build a new motor mount.

zog139
09-28-2011, 02:19 PM
You are entitled to your opinion. I would also like to see a B14 equivalent. Not everybody wants motors that cause the model to lift off at warp speed in every instance. Some models are going to benefit from a slower liftoff. Some contest models will benefit from a lower thrust curve. I also agree with you about no market survey being done. Not sure what that might yield. You speak in absolutes and your way is the best way. Try to be receptive to others thoughts and opinions. Try it you might actually like it :D

ghrocketman
09-28-2011, 02:43 PM
I am receptive to other thoughts...the problem is that manufacturers up until this point have been coming out with low-thrust BP SU motors that nobody seems to have been asking for. I think they are copping-out by just making easy-to-make motors.
Low-thrust long burn motors have a VERY narrow window of models that can use them at all, let alone optimally. High thrust motors (within reason, don't need a D159-x) can be used for virtually all models, even though the lightest models will not fly the highest on them. Contest flying represents probably less than .1 % of all flights flown, which makes very little sense to target motors to unless those fliers want to pay like $15 each for a B2-x whatever.

blackshire
09-28-2011, 02:47 PM
You are entitled to your opinion. I would also like to see a B14 equivalent. Not everybody wants motors that cause the model to lift off at warp speed in every instance. Some models are going to benefit from a slower liftoff. Some contest models will benefit from a lower thrust curve. I also agree with you about no market survey being done. Not sure what that might yield. You speak in absolutes and your way is the best way. Try to be receptive to others thoughts and opinions. Try it you might actually like it :DThe problem is that the motors that GH and others (including myself) want always seem to be "un-make-able" for one reason or another. B14s are too dangerous, A3-6Ts can't be packed within the 1.75" mini motor cases anymore, etc., and it gets frustrating.

ghrocketman
09-28-2011, 03:22 PM
The last EXCUSE we got from the guys that don't WANT to make B14's was that they wouldn't sell instead of using the mamby-pamby safety excuse that also holds no water.
They must have been using that extremely up-to-date market sales data from 1976 or 1977 that has to be accurate 35 freakin' years later. What a double-talk JOKE.
I would rather hear truthful "we dont wanna do it no matter what" than a rotten pack of BALONEY. Every excuse they had, I offered a valid counterpoint.

I'm glad Carl & co. will prove them wrong, AS USUAL.
Once he gets his Mabel a-crankin' I highly doubt I will be purchasing any 18mm motors other than Semroc. I support those responsive to us.

Chas Russell
09-28-2011, 04:26 PM
Having cussed and discussed things over the years with Carl, Sheryl, and Bruce it is evident to me that they "get it". This is not their first rodeo and they are doing great things with few people and the resources we provide them by being loyal customers.

My personal take is that motors, ANY motors, would be what I want now. They know the pros and cons. Many hobby shops or on-line dealers do not want to carry multiple BP or composite brands, although some do. Still, if they are cost effective and unique and available...

Carl, I would like to see the hybrid motors out first. They are somewhat different and no doubt will live up to your usual quality. It would cost you some money and labor costs to put a label on each kit that shows the recommended SEMROC motors, but since you batch a couple of kits when necessary, it is one minor additional step (done a hundred times or more each time). Eventually, you could tweak the individual kit instructions to make those changes.
I have 13 ammo boxes of motors (six are collector motors) plus the 100+ in my flying motor box. I would gladly sell some of my Brand E and Q motors at a loss to support buying SEMROC motors.

Just a few thoughts. B14's sometime in the future (for old times sakes...).

Chas

jharding58
09-28-2011, 05:03 PM
Perhaps an opprtune time to chime in with regard to the proposed suspension of DOT-SP 7887 regarding the labeling of rocket motors as flammable materials as opposed to Explosives. Estes published a pro forma in their recent email subscription service which would seem beneficial to all that ship motors either as whilesaler or retailer.

The address to which the response should be sent is:

specialpermits@dot.gov

The subject line should be:

DOT-SP 7887 Show Cause Response

Suggested copy for the email:

Dear Associate Administrator,

The purpose of this e-mail is to request that DOT-SP 7887 be kept in force as written. The Special Permit, previously DOT-E 7887 has been in place since 1978 and is used by many of us who enjoy hobbies including model rockets, motors and igniters.

To my knowledge, there has never been a reported incident involving the shipping or transporting of model rocket motors and igniters. Further, I believe that shipping these products as "Explosives" with attendant packaging requirements will create unnecessary fear and difficulty for those handling, transporting, receiving, storing, selling and using these products. Moreover the labeling as such will instill into the hobby a sense of public concern that that is both inappropriate and unwarranted.

After 33 years of use, the termination of the Special Permit is both not required, and assuredly damaging to an educational and recreational product that has an excellent record. In closing, I again request the Special Permit be kept in place as written.

Include your name and address here

SEL
09-28-2011, 09:27 PM
There are some new items on the Engine Survey page. Qualification testing on the Hybrid Port engines is complete and posted. Results for the 1/2A4, A7, 3/4B7, B7, 3/4C6, and C6 are given in a drawing and .eng files. The .eng files show slightly over the impulse limits on some of the engines. I did not stop to adjust the powder to keep all under the limits for impulse.
We are pleased with the results.

The hybrid port has a slightly deeper drill than standard to get the 18N peak. This is still not as high as the B14, B8, or C5 from the early days, but is higher than most engines in this class sold today. Now we have to decide whether to release the standard 11N peak as well as the hybrids or just release the hybrids and avoid the confusion.

A new .eng viewer is also included to analyze the results.

Feedback and comments are welcome!

Hey Carl,

I'm easy - I'll buy whatever you decide to put out there for us.

S.

BEC
09-28-2011, 09:48 PM
I'm with SEL....but would be most interested in motors that can't be had from the big E....these "hybrids" sound really interesting.

PaulK
10-05-2011, 12:31 PM
There are some new items on the Engine Survey page. Qualification testing on the Hybrid Port engines is complete and posted. Results for the 1/2A4, A7, 3/4B7, B7, 3/4C6, and C6 are given in a drawing and .eng files....The hybrid port has a slightly deeper drill than standard to get the 18N peak....Now we have to decide whether to release the standard 11N peak as well as the hybrids or just release the hybrids and avoid the confusion...Feedback and comments are welcome!I ran a quick sim of the B7 as the first stage booster in an Astron Farside, and it looks to be sufficient, at about 43fps on a 3' rod. Even the A7 should work, at 39fps, staging at 18'! A B7-A7-1/2A4 combo puts it at 580', staging at 64 & 141 ft. Here's a vote for the hybrids, so we can fly our small 3 stagers again!

Doug Sams
10-05-2011, 02:54 PM
I ran a quick sim of the B7 as the first stage booster in an Astron Farside, and it looks to be sufficient, at about 43fps on a 3' rod. Even the A7 should work, at 39fps, staging at 18'! A B7-A7-1/2A4 combo puts it at 580', staging at 64 & 141 ft. Here's a vote for the hybrids, so we can fly our small 3 stagers again!This sounds like fun :) BTW, I suggest swapping the A7-0 into the first stage and putting the B7-0 in the second. What are the staging altitudes for that?

Doug

.

Carl@Semroc
04-15-2012, 01:24 PM
I am still working on the Ex numbers and decided to put the 29mm back in. It turns out our current machine will make 29mm engines up to 3.25" long. It will take a totally new machine to go over 3.25" (bummer!)

I had missed the fact that Centuri bought the Coaster engine machine that made 1.0625" (27mm) x 8" long engines and sold them for a short while and then changed over to 1.125" (29mm) x 7.75" and 4.75". There was quite an evolution over a few year period.

1963
1.062" x 8" F11-3 49N-sec It and 54 sec Isp (low grade BP) same as Coaster 20lb

1964 1965 1966
1.062" x 8" F11-3 49 N-sec It and 54 sec Isp (still low grade BP ) called Hercules
1.062" x 5" E3.3-2 29 N-sec It and still low Isp called Atlas

1967
1.125" x 7.75" F14-4 37 N-sec It and 65 sec Isp ( higher grade BP) now called MINI-MAX 'PB'
1.125" x 4.75" E3.5-4 25 N-sec and 64 sec Isp now called MINI-MAX 'PB'

1969
1.125" x 7.75" F94-4 52.5 N-sec It and 85 sec Isp (highest grade BP) (metric labelling)
1.125" x 4.75" E7-4 25 N-sec and 54 sec Isp (large throat)

1971
1.125" x 7.75" F16-4 57.8 N-sec It and 94 sec Isp (highest grade BP) End burning
1.125" x 4.75" E15-4 39.6 N-sec and 83 sec Isp

1972
replaced by Enerjets, new case sizes are 1.125" x 3" and 5"

The LT-110 was the engine tube for the early Coaster engines and was replaced by the LT-115 for the 29mm engines and Enerjets.

The new engine survey shows some decision points. The 3/4E21 at 26 N-sec is the largest with 30.0 g or less of propellant. So all the 29mm engines in the 2.75" long casing would be able to be mailed via USPS ground with no additional charges. The full E20 at 3.25" and the 3/4F19 would have to be shipped with HAZMAT. The 3/4F19 at 62.5 g of propellant would be the largest we would ever make. The BATFE discussions we have had made us decide to never go more than 62.5g. We would have to sell them to certified users only, HAZMAT fees, and track each engine from cradle to grave. As long as we keep each engine under 62.5 g, we only track them until they are produced. Once they are packed in the casings, the BATF has no further interest in the BP or the engines.

Let us know what you think about the 29mm engines.

kurth
04-15-2012, 01:45 PM
Let us know what you think about the 29mm engines.


They sound like a lot of fun. I will definitely try several of them in my SLS Brighton and be standing by for more kits from Semroc to use them in. :) :D

Initiator001
04-16-2012, 12:04 AM
The 29mm motors sound good, Carl.

Make some up and I will place an order. :D

Doug Sams
04-16-2012, 09:34 AM
Let us know what you think about the 29mm engines.You have to ask us if we want to buy 29mm BP motors? :D

The ¾E21 (-0) sounds perfect for one of my stagers that turned out to be too much for the lone D12-0 in the booster. So, yeah, bring 'em on!!

[Edit: I'll build a new booster just for that motor.]

Doug

.

ghrocketman
04-16-2012, 09:59 AM
The 29mm motors sound great.
They don't sound like those wimpy-thrust "coming soon FOREVER" Thunderjets that I'm convinced have become vaporware after showing at trade shows....

Make sure you can do tham at a reasonable price point....

Any idea WHEN we are going to be able to get our paws on ANY Semroc engines ????

Carl@Semroc
04-16-2012, 01:14 PM
...Any idea WHEN we are going to be able to get our paws on ANY Semroc engines ????There are not enough hours in a day and it seems like there are fewer all the time. We have to take in outside work to help pay the bills and still have to release a new kit each month. Having to invest over 200 hours to release a kit that will gross about $5,000 over its life means it takes most of our time to just stay even. If we could take a few months to work full time on engines, we would have them, but we would be out of business in the process.

Since the projected annual sales figures from the Engine Survey are only about $17K from SAM's, we can't afford to spend the time on engines that we would like to. We work on them when we get free time, but it is rare right now. We hope when the economy gets better, we will be able to burn off some inventory to help finance engines.

ghrocketman
04-16-2012, 02:10 PM
Carl,
Totally understand.
You being gracious enough to give us an explanation is more than any other company ever cares to do.
Just another reason Semroc is #1 with ZERO close competition in my book. You and your entire team DO IT RIGHT !!!

I offer to 'beta test' any engines you find needing it ! :D :D :D

SEL
04-16-2012, 10:22 PM
I am still working on the Ex numbers and decided to put the 29mm back in. It turns out our current machine will make 29mm engines up to 3.25" long. It will take a totally new machine to go over 3.25" (bummer!)

I had missed the fact that Centuri bought the Coaster engine machine that made 1.0625" (27mm) x 8" long engines and sold them for a short while and then changed over to 1.125" (29mm) x 7.75" and 4.75". There was quite an evolution over a few year period.

1963
1.062" x 8" F11-3 49N-sec It and 54 sec Isp (low grade BP) same as Coaster 20lb

1964 1965 1966
1.062" x 8" F11-3 49 N-sec It and 54 sec Isp (still low grade BP ) called Hercules
1.062" x 5" E3.3-2 29 N-sec It and still low Isp called Atlas

1967
1.125" x 7.75" F14-4 37 N-sec It and 65 sec Isp ( higher grade BP) now called MINI-MAX 'PB'
1.125" x 4.75" E3.5-4 25 N-sec and 64 sec Isp now called MINI-MAX 'PB'

1969
1.125" x 7.75" F94-4 52.5 N-sec It and 85 sec Isp (highest grade BP) (metric labelling)
1.125" x 4.75" E7-4 25 N-sec and 54 sec Isp (large throat)

1971
1.125" x 7.75" F16-4 57.8 N-sec It and 94 sec Isp (highest grade BP) End burning
1.125" x 4.75" E15-4 39.6 N-sec and 83 sec Isp

1972
replaced by Enerjets, new case sizes are 1.125" x 3" and 5"

The LT-110 was the engine tube for the early Coaster engines and was replaced by the LT-115 for the 29mm engines and Enerjets.

The new engine survey shows some decision points. The 3/4E21 at 26 N-sec is the largest with 30.0 g or less of propellant. So all the 29mm engines in the 2.75" long casing would be able to be mailed via USPS ground with no additional charges. The full E20 at 3.25" and the 3/4F19 would have to be shipped with HAZMAT. The 3/4F19 at 62.5 g of propellant would be the largest we would ever make. The BATFE discussions we have had made us decide to never go more than 62.5g. We would have to sell them to certified users only, HAZMAT fees, and track each engine from cradle to grave. As long as we keep each engine under 62.5 g, we only track them until they are produced. Once they are packed in the casings, the BATF has no further interest in the BP or the engines.

Let us know what you think about the 29mm engines.


I'm in!!


S.

gpoehlein
04-02-2013, 07:33 PM
I know this thread has been dormant for a couple of years now, and I was just wondering if any more progress has been made on this or if motors from Semroc is a totally dead issue? If it is dead, I can completely understand that Carl and crew are putting their energies into producing more and better models. But I would still love to see a few of the low powered motors brought back into production that have not been available for a very long time. At this time, I would love to see the S motors brought back - I know we can use T motors in adapters, but an A10-3T is not the same as an A8-3S in a classic model that was originally designed for the short motors (such as the Midget).

Just out of curiosity, is there enough room in an 18mm short casing for the delay and ejection of an A8-5? And a 1/2A6-4S would be awesome for low power two stagers as well!

mwtoelle
04-02-2013, 07:48 PM
If you use the current Estes thin wall casings (I.D. 0.500"), it is about 1½" from the front of the casing to the front of the clay cap over the ejection charge. Estes did offer A5-0S, A5-2S, and A5-4S motors in the 1970, 1971 (both editions), and 1972 catalogs.

Doug Sams
04-02-2013, 09:18 PM
At this time, I would love to see the S motors brought back - I know we can use T motors in adapters, but an A10-3T is not the same as an A8-3S in a classic model that was originally designed for the short motors (such as the Midget).

Just out of curiosity, is there enough room in an 18mm short casing for the delay and ejection of an A8-5? I have used, with great results, sawed-off A8-5's and B6-0's. So you should have no problems using a cut-down A8-3 should you try it.

I stuffed some wadding into the end of the motors while I was cutting them to make sure a spark from the sawing process didn't set off the any stray powder.

And a 1/2A6-4S would be awesome for low power two stagers as well!No doubt, a ½A6-4 would be a great companion to the current ½A6-2, but I'm afraid the better (ie, more realizable) answer is a ½A3-4T adapted up to 18mm.

Doug

.

gpoehlein
04-02-2013, 09:54 PM
I have used, with great results, sawed-off A8-5's and B6-0's. So you should have no problems using a cut-down A8-3 should you try it.

I stuffed some wadding into the end of the motors while I was cutting them to make sure a spark from the sawing process didn't set off the any stray powder.

No doubt, a ½A6-4 would be a great companion to the current ½A6-2, but I'm afraid the better (ie, more realizable) answer is a ½A3-4T adapted up to 18mm.

Doug

.

No can do - the only place I get to fly is at our club launches, so NAR rules are always in effect (no modified motors). So cutting down a regular motor is not an option. And I thought of using the adapter with a 1/2A3-4T (I have the Semoc Midget that comes with T motor adapter sleeves), but as with using the A10-0 and A10-3T, it adds weight to the motor end of the model that wouldn't be there with an S motor using the current style casings. Granted, not a big deal, but still worth thinking about.

Greg

blackshire
04-03-2013, 01:49 AM
No can do - the only place I get to fly is at our club launches, so NAR rules are always in effect (no modified motors). So cutting down a regular motor is not an option. And I thought of using the adapter with a 1/2A3-4T (I have the Semoc Midget that comes with T motor adapter sleeves), but as with using the A10-0 and A10-3T, it adds weight to the motor end of the model that wouldn't be there with an S motor using the current style casings. Granted, not a big deal, but still worth thinking about.

GregAnd don't forget the Centuri birds that were designed for the shorties--the original Lil' Herc and the Firefly two-stager! Maybe Carl could make a vacu-formed (or cast polyurethane resin) version of the new Estes two-piece red plastic motor adaptors, but sized to "convert" 13 mm mini motors to shorty S motors. Also:

Regarding your NAR club difficulty (Re: using "cut-down" shorty motors at club launches), I see a niche market for motor, er...re-printing... I'm a NAR member, too, but if one -secretly- breaks a rule that is a "victim-less crime" anyway, I have a hard time working up righteous indignation against violators. To me, it just isn't in the same category as, say, launching rockets at angles of less than 30 degrees to the local vertical, or launching flammable or explosive payloads--those are clearly dangerous activities, while using "cut-down" S motors is a "paper/political" violation. If I were in your situation, I'd keep my own counsel and enjoy some S motor nostalgia flying.

Doug Sams
04-03-2013, 02:46 AM
...but as with using the A10-0 and A10-3T, it adds weight to the motor end of the model that wouldn't be there with an S motor using the current style casings. Granted, not a big deal, but still worth thinking about.Greg,

Most of the old motor cases had extra thick walls, similar in thickness to a T motor inserted into a spent case. The mass is fairly close. I've flown stock Midgets using the 18-mm adapted combo of A10-0T to ½A3-4T many times with no stability issues.

Doug

.

blackshire
04-03-2013, 03:23 AM
Greg,

Most of the old motor cases had extra thick walls, similar in thickness to a T motor inserted into a spent case. The mass is fairly close. I've flown stock Midgets using the 18-mm adapted combo of A10-0T to ½A3-4T many times with no stability issues.

DougI had equally good results flying an Estes Sprite clone using a 13 mm-to-shorty "conversion" motor adaptor made from BT-5 with two centering rings and a mini motor clip. It could also be used in an original (shorty motor powered) Centuri Lil' Herc. It would even be "NAR Kosher" for club launches if a streamer was taped to the mini motor adaptor's BT-5 tube and wrapped around it before the adaptor was slipped into the rocket; the shorty motor adaptor would descend under its streamer while the Lil' Herc used tumble recovery as per its design.

ghrocketman
04-03-2013, 09:29 AM
Would also REALLY like to know if we are going to see any sort of Semroc motors in the NEAR future.
I for one would gladly like to see them come out with say half a dozen new motors not on the market (one of which MUST be the B14) soon rather than any new kits.
The LPR/MPR market needs new MOTORS far more than kits.
They already offer more kits than all the other major LPR/MPR suppliers combined.

Royatl
04-03-2013, 11:33 AM
I have used, with great results, sawed-off A8-5's and B6-0's. So you should have no problems using a cut-down A8-3 should you try it.

I stuffed some wadding into the end of the motors while I was cutting them to make sure a spark from the sawing process didn't set off the any stray powder.

No doubt, a ½A6-4 would be a great companion to the current ½A6-2, but I'm afraid the better (ie, more realizable) answer is a ½A3-4T adapted up to 18mm.

Doug

.

Indeed, after accidentally flying a couple of 1/2A6-4's in an Astron Scout at NARAM-50 (didn't realize they were LONG decertified), and finding they were the PERFECT motor for the Scout, I've used adapted 1/2A3-4Ts in it for even better flights.

Doug Sams
04-03-2013, 06:49 PM
Indeed, after accidentally flying a couple of 1/2A6-4's in an Astron Scout at NARAM-50 (didn't realize they were LONG decertified), and finding they were the PERFECT motor for the Scout, I've used adapted 1/2A3-4Ts in it for even better flights.With the four sec delay (on a half A), is it already over the top and heading down at ejection? I bet that makes for a very interesting flight :)

BTW, I think I only ever flew my clone once or twice, then retired it, so I don't have many flights to recall and can't remember what motor(s) I flew, but I'd swag ½A3-2T. That woulda been circa 2001.

Doug

.

Royatl
04-03-2013, 09:08 PM
With the four sec delay (on a half A), is it already over the top and heading down at ejection? I bet that makes for a very interesting flight :)

BTW, I think I only ever flew my clone once or twice, then retired it, so I don't have many flights to recall and can't remember what motor(s) I flew, but I'd swag ½A3-2T. That woulda been circa 2001.

Doug

.

No! It is right at peak, so the tumbling starts immediately. That's what impressed me at NARAM. it was just *so* perfect. The adapted mini motor flight was just as good.

Doug Sams
04-03-2013, 09:59 PM
The adapted mini motor flight was just as good. At the risk of venturing off topic, I think that illustrates one of the challenges the T motors have always faced. Folks get it in their heads, at some level or another, that they're not as powerful as 18mm motors. I know, in my case, I lost a Quark all those years ago thinking that little 13mm motor wouldn't impart enough woosh to lose it. WRONG!

I think even Estes recognizes the paradigm of the form factor resulting in them selling four AxT motors for the price of three 18mm A motors.

In short, in most applications, the T motors can be readily substituted for the 18mm motors by just using spent motor cases as throw-away adapters. That gives us the ¼A3-3, ½A3-2 and -4, and full A3-4 and A10-3 motors to fly in shorty applications as well as full length. That is, with adapters, most of the 18mm A series could be replaced (altho I know that'll never happen). One thing the full sized A's do offer is the longer -5 delay, and maybe a bit more lifting thrust off the pad. And, as Fred will point out, the full sized A's have a larger nozzle which helps in staging, although I've had great success staging to the smaller ones.

So I believe you when you say your Scout flew just as well on the T motors :)

Doug

.

SEL
01-14-2021, 06:26 PM
I have added an online engine survey to get you input. This is in a constant state of change. As more engines are better characterized, the data will be updated. I will be adding some links to .eng files for Rocksim as I get them completed.

The engines longer than 3.25" are in the future, since they will require a new machine, but we do want to get an idea of interest in current sizes, as well as future sizes.

This survey is only for SAM's until we are ready for a larger public exposure. Please send your comments, errors, omissions, ideas, etc. in this thread. We want all SAM's to have as much input in this process as possible.

The link is Engine Survey (http://www.semroc.com/Store/Scripts/enginesurvey.asp). You have to login to see it. There is a current limit of 100 packs per engine so the results do not get badly skewed. (GH... don't break the B14 buttons! :chuckle: )


Does anyone have a copy of the list of motors from this survey? Thought I made a .pdf but can't find it. I know there were a few versions, so the later the better, but I'll take what I can get.


Thanks in Advance,



Sean