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bikegod
09-24-2006, 07:47 PM
Well, I treated myself to an SLS Laser-X with all the different engine mounts (Dual 24s, Quad 18s) and worked like a demon smoothing the fin joints and painting it to match the picture on Carl's site. Even though there is a drip in one fin and loads of paint on it, it's the best work I have ever done (pictures later).

I felt the need to have the regular scale Laser-X so went out and treated myself, with hopes of making it a Mini-Me version of the SLS.

The construction is totally different and I really felt the challenge of building this small scale rocket. Nothing wrong with it, just very different.

To date, I have learned how to finish (and refinish) balsa and basswood fins and nosecones, as well as plastic as well as the differnt grades of tubes out there. I have gleaned a wealth of knowledge from this board and have never been dissapointed for lack of help here.

So here is yet another question on building techniques for those of you familiar with working with card stock/paper. The transition on the Laser-X is a cone you make out of cardstock and glued to the BT and a centering ring. That part went fine, but I was wondering how you finish the seam. Obviously with cardstock, you would want to keep from getting it too wet. I also assume that you can't sand it too much. The little tab that you glue to make the cone creates a tiny hump in the cone that will need to be "smoothed over" eventually.

I am guessing light amounts of fill and finish for the seam, but chime in here. I wonder how much paint I can put on at a time.

I'll try to get some pics of the both of them soon. The SLS got several coats of gloss today and is in the shed drying right now. My shed is great for water and wind proof, but I have gotten a gnat or two in paint before. Nothing some 240 grit can't take care of.

Can't wait for my 24mm RMS to arrive. Heard that Rouse Tech may be having some issues. I hope that won't be for long.

stefanj
09-24-2006, 08:48 PM
I would avoid using Fill n' Finish directly on the shroud.

I use Minwax Wood Hardener on "light duty" shrouds (e.g., boat tail shroud of my Starfire clone). This impregnates the paper and "plasticizes" them. At that point water-based fillers can go on.

On heavy duty models I use finishing epoxy . . . first to harden the paper, later mixed with microballoons to give a smooth finish.

Getting a good body tube/shroud transition is a tough task. A smooth rounded transition might be easier than a nice crisp angle; I've only tried the former.

The boat tail seen on the attached picture is made from two paper shrouds with epoxy in between, and lots of finishing epoxy / microballoons on top. I used a belt sander to smooth out the coated surface. The seam is hidden under one of the fin lines.

Doug Sams
09-24-2006, 09:03 PM
So here is yet another question on building techniques for those of you familiar with working with card stock/paper. The transition on the Laser-X is a cone you make out of cardstock and glued to the BT and a centering ring. That part went fine, but I was wondering how you finish the seam. [snip] I am guessing light amounts of fill and finish for the seam, but chime in here. My card stock transitions usually look pretty bad before I get to the FNF. I'm talking Reluctant-Astronaut-Peanut-Butter-Crackers-and-Mag-Tape bad here :) But they always look good after the FNF.

I usually slather it on at the for and aft joints in an attempt to round off the edges. And the seam gets a bit, too. For me, the trick is then using a paint brush wetted with thinned FNF to tool, shape and smooth the thick stuff. Here's one I did a long time ago: http://home.flash.net/~samily/jordo/Jordo2.html

Depending on your seam, multiple passes may be necessary to get it smoothed out wide enough to blend in. By that I mean: apply, let dry, sand, apply some more...

HTH.

Doug

sandman
09-24-2006, 09:54 PM
I soak in CA (super glue) first to harden the paper.

Spread it out with a piece of plastic or something that won't stick as you are applying it.

Oh...and do this outside...the CA fumes are NASTY!!!

ar51rognlie
09-24-2006, 11:31 PM
When I make a transition, I cut off the tab and glue it (overlapping 1/2) to one of the ends. Then glue the other edge (butt joint) over the other half of the tab. No bump to try to even out that way. Easier to fill and smooth.
I got this from the Tim's Apogee site, where he has a video available demoing the technique.
After the transition is positioned and glued, I use some CyA to stiffen (plasticize) it.

-- AL

A Fish Named Wallyum
09-25-2006, 12:55 AM
I soak in CA (super glue) first to harden the paper.

Spread it out with a piece of plastic or something that won't stick as you are applying it.

Oh...and do this outside...the CA fumes are NASTY!!!

Depends on the brand. Some of them burn my eyes. Others I don't even notice. :confused:

bikegod
09-25-2006, 06:46 AM
Thanks for all the input!

I have used the fill/sand/fill method for my last set of fillets (looks really good). Getting quite used to how much water I will use depending on what I am doing on the bird. I recently did up the launch lugs on LPSLV. I really laid it on thick, then sanded away what I didn't want (sometimes using a detail sander). I trimmed the fore and aft of the lugs at an angle and have been pleased at how they came out looking when the paint dried.

I'll keep you posted.

Ltvscout
09-25-2006, 07:19 AM
Depends on the brand. Some of them burn my eyes. Others I don't even notice. :confused:
You're not supposed to use them as eye drops!

Bob Thomas
09-27-2006, 01:01 AM
One of the cooler rockets of my youth. I completed the semroc model (sans semroc decals) and plan to purchase the SLS, when I have space! Was wondering how the tail is finished in the SLS. I know the mounts are swapable - any concessions to the design to accomodate this feature? Gratuitous pic included below!

Bob H
09-27-2006, 06:52 AM
One of the cooler rockets of my youth. I completed the semroc model (sans semroc decals) and plan to purchase the SLS, when I have space! Was wondering how the tail is finished in the SLS. I know the mounts are swapable - any concessions to the design to accomodate this feature? Gratuitous pic included below!The 29mm mount that comes with it has the "cooling fins" and looks just like the small one.

The 4 X 18mm mount has the "cooling fins" between the 4 tubes and the 2 X 24mm mount is just flush with the back end of the body tube with no "cooling fins".

Green Dragon
09-27-2006, 07:31 AM
I always finish my paper transitions with titebond.

just after attaching tot the model, coat with 6-8-10, whatever.. THIN coats, which do not wet the paper enough to wrinkle up , after a few coats get it 'sealed' then you can use more at a time.
After many coats it gets nice and stiff, and can be lightly sanded as needed ( which also promotes paint adhesion ).
I used this technique on my K27 hoJO, Vector V, etc and have enen made conical nosecones out of rolled up paper coated with tiebond.

~ AL

Eagle3
09-27-2006, 08:11 AM
I coat with thin CA. If it's a big transition like on my Aegis X then I also drill holes in the aft ring and fill the cavity with expanding foam.

bikegod
09-27-2006, 11:45 AM
I had the best time building each of the engine mounts for the SLS. I did put the 24mm adapter (after discussing the engines in another thread). I plan on using the RMS. The twist-lock feature is really great. Haven't been very excited about the dual mount, it's kinda boring looking and the biggest estes engines that would go in there are a couple of E-9s.

When I finished the single mount, I painted the whole thing white, then cut little strips of tape to fit between the cooling fins, rubbed them down with a pencil, and painted the whole thing red. Left all the cooling fins red and the spaces white.

I was going for making it look just like the pic.

Watch how much paint you get on the rings and in the end of the body tube, they can really make the engine hard to change.

Tau Zero
08-31-2008, 10:30 PM
"Inquiring minds want to know." :eek: ;)


Jim, I've seen your rockets first-hand, and I've been wondering exactly how you construct your paper transitions. I don't recall seeing the traditional "overlap seam," and I was hoping you'd tell us how you pull off this particular (potentially "sticky") technique.

Pictures would be good, too.


Over in the "RockSim: Newsletters from Apogee (http://www.oldrocketforum.com/showthread.php?t=1259)" thread, I wrote:You can find additional information on the subject in "Peak of Flight" #136, in the article "Make Your Own Transitions," which tells you how to get rid of that unsightly seam, as well as propaganda about using rubber cement instead of white glue.

So I'm trying to re-learn this technique correctly 30 years later. :o


Thanks, buddy! Hope all's going well for your "herd." ;) :D


Cheers,

Solomoriah
08-31-2008, 10:58 PM
I'm not him, but I know how to do it. Cut the tab off, and glue it halfway over one edge of the transition; when it's dry enough, roll up the transition and glue the tab over the other edge.

Dang, I just re-read that and I don't get it. But it's simple.

Instead of a cone, imagine you are rolling up a tube. Looking at it end-on, you're seeing this:

http://rocketry.newcenturycomputers.net/temp/tab-example.png

So the cut edges of the transition are butt-spliced, with the tab hidden on the inside. Cut the tab a bit short on the "fat" end, and a bit more short on the "thin" end, so it doesn't push the transition out from the body tubes and leave an unsightly dent.

James Pierson
08-31-2008, 11:08 PM
CenturiGuy Quote:

JP's Transition secrets?

"Inquiring minds want to know."


Jim, I've seen your rockets first-hand, and I've been wondering exactly how you construct your paper transitions. I don't recall seeing the traditional "overlap seam," and I was hoping you'd tell us how you pull off this particular (potentially "sticky") technique.

Pictures would be good, too.

Ancient Chinese Secret :D Jay :cool:


I usually completely forget to leave on the overlap tap when laying out and cutting my transitions, besided I never liked the seam left by that technique. I have instead gone to what we carpenters would call a "Blind Gusset" method.

The "Gusset" being an 1/4 inch wide scrap transition paper 1/8 inch shorter that the overlap joint itself. The "Blind" part being that it is hidden on the inside of the transition.

I first roll the transition into a curved shape close to its desired shape.

Next I use Tightbond II and lightly glue the gusset onto one half of the joint on the inside of the transition. Center the gusset on this half.

Let it dry securely for about 10 minutes. Be sure to wipe any excess glue off of the gussetts other half.

Finish off the transition by gluing on the other side of the transition to the other side of ther gusset. If the paper joint is not perfect, don't worry, as Kliz will easily fill any voids.

OK, all completely Confused :confused: , good, me too :D .

Solo has got it. See graphic above. ^

Hope this helps, JP.

James Pierson
NAR# 77907
.

Tau Zero
08-31-2008, 11:17 PM
Ancient Chinese Secret :D Jay :cool: Jim,

Now *why* am I *not* surprised at your response? :eek: :rolleyes: ;)


I'm not him, but I know how to do it. Cut the tab off, and glue it halfway over one edge of the transition; when it's dry enough, roll up the transition and glue the tab over the other edge.

Dang, I just re-read that and I don't get it. But it's simple.

Instead of a cone, imagine you are rolling up a tube. Looking at it end-on, you're seeing this:Chris,

Thanks for the great graphic! I've also been wondering if I should use some blue painters tape to keep things correctly aligned... :o


Cheers to you both,

Solomoriah
08-31-2008, 11:32 PM
Use cellophane tape, on the inside. And leave it there (so long as you tear it the right length so it does not interfere with any glue joints).

Ancient Centuri secret... as in, excellent way to assemble a Vulcan.

Maniac BAR
09-03-2008, 01:40 AM
Use the butt joint method and lots of thin CA. The CA will harden the paper making it very stiff and is easy to sand smooth. Primer will stick just fine to it as well. The CA will make the paper feel like a plastic part it is that good. :)

Do watch out for the fumes. They will bring tears to you eyes real fast. As you apply the CA you can see what looks like smoke coming off of the paper. Stay away from the smoke!!!! Don't go into the smoke!!!! Stay away from the smoke!!!!

OK, I think that one has passed :o

Another gratuitous picture as well.

Bob Kaplow
09-03-2008, 06:52 AM
Another trick is to replace the paper with thin styrene sheet. Much easier to finish, as long as you're not spraying dope.

falingtrea
09-03-2008, 12:30 PM
I have used this (http://www.delorie.com/rockets/transitions.html) transition calculator and found it to work very nicely. It has both tab and gusset attachment options.