Centuri Launch pads and Firing panel...
 

Hi all,

I have an L1A 100 and 2 L1A 77's and an EP-612 Firing Panel that still works; key, bulb and all. It has the black crinkle paint finish and about 25 feet of wire.

One of the '77's and the '100 are as old as dirt; the other '77 is new in the box.

The used pads need cleaning/restoring. They are all made of some sort of Luan (but
not quite) 3-ply plywood. The larger pad has one honking big blast deflector!

What would be the best way to finish them after cleaning? I'm thinking a neutral stain.

l have to say that Centuri had it sorted out in comparison to the other brands' - 'controller'
wise. It's a tank!
Bob

p.s. yeah, gonna use 'em...

Hey, could you photo-document these launchers? Scan in the directions, trace the legs, make measurements of the metal parts, etc. ?

I'd love to try re-creating them.

The wooden Centuri launchers were still around when I was getting into the hobby, and my grade school had one of the small ones, but they quickly disappeared. I think the pneumatic servo-launcher made its first appearance in the 1971 catalog which was the first Centuri edition I got my hands on.

The 1971 catalog still listed the fancy metal launch panel, but had introduced a black plastic hand-held model. I had two of these at one point. They were very, very sturdy and futuristic compared to the oval "Astron" launch controller. I sold them to a collector many years back.

Sorry,

At this time no scanner here. However I will make/trace the patterns.

Bob

I have one of the servo launchers...someplace. It's kind of a cool idea with the pneumatic control.

Sort of like a relay system. but pneumatic.

I can easily reproduce the wooden parts. I even made some of the old Tilt-a-Pad launchers from some old redwood I found.

The only change I made was to increase the disc size to 4" from 3 3/4".

I only had a 4" hole saw. :o

The one in front has a 4" disc(top) and the one in back I sanded down to 3 3/4"

The bigger one looks better...and a lot less work!

I had one of the servo launchers when I was a boy...it had been my cousins and then became mine when he got out of rocketry and dropped off a bunch of great stuff.

The launcher was cool and very portable....but...I discovered a fatal flaw in the design one day.

The safety interlock key is on the pad, not on the launch controller (which is a plunger connected to a 10 foot tube that inflates a balloon that pushes the batteries against the contacts to fire the igniter). One fine afternoon in the mid 1970s, I decided to fly my Groove Tube. I set it up on the red servo launcher, hook up the igniters, put the key in then walk back to the launch button and push it...nothing happened. I noticed that the light in the safety key was out so I went and checked the clips and the igniter (which hadn't fired). I then wiggled the key and got it seated better...the light came on and then I heard a hissing sound next to my ear....the rocket was taking off not 3 inches from my head! I ducked quickly and off it went for a successful flight but a rattled flyer.

Here was the problem...when I put the plunger down on the ground to check the pad, it was slightly depressed. When I wiggled the key/light (again, on the launch pad itself), it made contact...and the balloon was, unknown to me, inflated enough to trigger a launch. It was at the ripe age of maybe 13 or so that I realized that if I ever designed a launch control system, the safety interlock key must be placed with the launch button -- not on the launch pad.

I recently picked up one of the Centuri wooden launch pads, still unassembled in the box. The one I have is LIA 77. Outstanding quality parts though the fit is very tight so I haven't worked on putting it together yet. It will also need to be stained and varnished. Not sure when I'll use it but sometime when I'm flying Centuri clones I will.

Both. You want it on both. When you have a system where there's more than a few steps from controller to pad, the system must be disarm-able from either end. All the HPR stuff I have ever worked with had relayers, and all the relays had safing switches on them so the flyer can set up his rocket without worrying that someone at the rangehead may accidentally arm and fire his rocket.

The only downside to this is the long walk back to the pad to arm it after you've forgotten to :o And after you've waited thru an entire cycle of launching from that set of pads.

Doug

.

I've never laid hands on one of these, but based on what I've seen and read over the years, it sounds gimmicky. I suppose that's the basis of the cool factor. But it really does sound Rube Goldberg. It's needlessly complex - I can think of many ways of closing a switch that don't involve balloons and hoses :)

Surely a little heavier wire or a relay could have been used in lieu of the pneumatics at comparable cost. Of course, it wouldn't have been as cool.

Nor as kludgy.

Doug

.

And in the rare event the relay contacts have fused closed, the relayer units are designed so that the piezo element sounds whenever the leads are energized. Even so, some have developed the habit of touching the clips together and looking for a sparks before hooking up to the igniter. Probably not a bad idea.

The only Centuri launch equipment I still have is the old wooden box with an asbestos pad.


Bill

Doug, since Centuri designed some of their products (such as the 1340 Sounding Rocket) with industrial and scientific customers in mind, I'm not surprised at the design of the pneumatically-activated Servo Launcher. My guess is that it was originally designed for launching lightning research rockets (the kind that carry fine, ground-connected copper wires to induce lightning strikes at the instrument-equipped launch sites).

Using non-conducting pneumatic tubing instead of copper ignition lead wires decreases the risks of the launching personnel getting struck by the lightning discharges. A more recent lightning rocket experiment series (documented in National Geographic some years ago) utilized Aerotech Arreaux rockets trailing wires into the sky. The experimenters blew into long lengths of surgical rubber tubing to actuate the pneumatic ignition circuit contact mechanisms at the launch pads. (When I expressed interest in replicating these experiments in our back yard in Miami [I likened it to the prophet Elijah calling fire down from heaven], my mother answered with a firm "NO!") :-)

Bill, is it similar to these http://www.ninfinger.org/rockets/ca...65/65cen12.html ? Semroc could bring back that launch pad as a "Retro-Repro" product to be part of a re-issued Centuri "Beginner's Outfit" (with a Micron rocket kit) and/or a re-issued "Rocketeer's Outfit" (with Payloader II and Javelin rocket kits). Using the new resin-locked asbestos sheets, they could even include the asbestos jet deflector for the launch pad! How about it, Carl? :-)

It's always a good habit to check for juice at the pad BEFORE connecting the leads. I remember one LDRS in particular when I was doing a video interview with a flyer out at the pads while the the entire bank was being loaded with rockets. In the middle of the interview while I had the camera to my eye, I heard the tale-tale sound of 'ignited' thermalite sizzling right beside us. At the same time, the dude at the very adjacent pad 'rolled' out of the way screaming "Lookout!". He had just connected his pad leads to a J800, and about one second later ( before I could even take single step), off it went, about three feet from where I stood. Luckily, the motor did not cato and the launch phase was nominal.

But I can attest that a J800 makes a pretty good whoosh from three feet away (and I've seen a LOT of high power flights over the years).

Earl

You would make me go dig for it, would you? It is that one, an LIA-50 that I got in one of the Centuri clearance specials. The asbestos pad, clip leads and assembly instructions are taped into the bottom of the box. The angled steel blast deflector was separate and is floating around here somewhere. I guess I ought to put the asbestos into a ziplock bag...


Bill

I don't suppose you got that on video...


Bill

Thank you for confirming the launch pad's model number! I wouldn't launch any rockets from it with the asbestos pad in place, but if it's in storage the asbestos pad shouldn't be a problem. The real dangers were/are caused by the sprayed-on asbestos that was applied to pipes and electrical conduits in buildings and onboard ships. This type had asbestos fibers readily "flake off" into the air where they could be inhaled. An asbestos pad is not a problem unless something erosive is done to it that disperses asbestos fibers into the air. The new asbestos insulation panels are treated with a high-temperature resin to lock in the asbestos fibers.

I had one of those square pads. I remember picking off bits of asbestos and rubbing it between my fingertips. Odd stuff.

Hi Blushingmule,

If you still have it, would you mind taking a look at your ID-100 igniter-deflector (blast deflector) for the Centuri LIA-100 Heavy Duty Model Rocket Launcher to confirm if it matches the ID-100 deflector that I have please? Rocketguy101 and I have been working to document it at the following thread:
https://forums.rocketshoppe.com/sho...00&postcount=70

My Centuri ID-100 deflector assembly is 3.9" tall. See attached image of my LIA-100 Heavy Duty Launcher. Also attached is a comparison photo showing difference in size between my ID-100 deflector and my ID-77 deflector.

Thanks,
Jeff Jenkins
aka: Faithwalker

For anyone who is interested, I am posting a copy of the instructions for the Centuri LIA-100 Heavy Duty Launcher and a hi-res copy of the instructions for the EP-612 Professional Firing Panel pictured above. The EP-612 instructions were graciously provided by Lee Piester. Thanks Lee!

Kind regards,
Jeff Jenkins
aka: Faithwalker
NAR #46879

Plans for the ID-100 igniter deflector used with the LIA-100 Heavy Duty Launcher are in post #70 at this link:
https://forums.rocketshoppe.com/showthread.php?t=14833

Kind regards,
Jeff Jenkins
aka: Faithwalker
NAR #46879

Thank you for posting those (I admire your YORF "handle," too)! ALSO:

If Dewalt pursues his interest in producing clones of them (as he wrote in Reply #65 *here*: http://www.rocketshoppe.com/forums/...33&page=7&pp=10 ), reprints of your scanned instructions (with an added disclaimer line like that in Semroc's "Retro-Repro" rocket kits) would be perfect to supply with them. (The Centuri "Professional Firing Panel" would be easy to make, using a standard aluminum electronic projects box [as Centuri themselves did] for the hand-held controller; the Centuri "Lectra-Line 1" [and 2] launch controllers--see Reply #62 from Hans "Chris" Michielssen that's also in the above-linked thread--could be 3D printed or duplicated in polyurethane casting resin in RTV rubber molds [their resin parts could even be dyed yellow or black, to match the original ones].) Now:

All we need to complete the Centuri GSE (Ground Support Equipment) line are reproductions of the Centuri Servo-Launcher (it used a pneumatic switch!), Powr-Pad, Powr-Control, and Power Tower (and maybe--just for giggles--even a Pola-Pulse Launch Controller [with internal mods to use rechargeable lithium-ion or lithium-polymer batteries instead]; you can see all of these GSE items *here*: http://www.ninfinger.org/rockets/no...a/72cen052.html and http://www.ninfinger.org/rockets/nostalgia/82cen26.html )... :-) (Actually, although I suggested bringing these back only half-jokingly, with today's home production capabilities, it's no joke at all; they really could be made today if desired.)

Some Power Tower info here: http://www.oldrocketforum.com/showthread.php?t=16800

Both versions’ plastic parts appear to be identical to the first two versions of the Estes Porta-Pad except for color. Lots of details on the third page of this thread.

They are identical except for the blast deflector. Same mold. I'd post pics of mine, but I'm too lazy tonight.

That’s OK. I know that parts I have all interchange even between the tall and “redesigned for more stability” versions.

Centuri Power Tower ID-65 Blast Deflector
 

Bernard,
Thanks for documenting the Centuri Power Tower that you have! I've been working on a SolidWorks 3D CAD model of the ID-65 Blast Deflector (product no. 5806) for it.

I've attached an image of my 3D prototype so far. It's pretty close, but I'm still tweaking it to get a good flat pattern.

Kind regards,
Jeff Jenkins
aka: Faithwalker
NAR #46879

I see what you mean! The printed, black text-on-chrome Power Tower decals are not only informative (including a misfire checklist, recommended batteries, and a launch elevation reminder, as David Stribling's Power Tower photos show at the top of page 2 [Reply #11] in that thread), but having those shiny decals on all sides of the launcher is very helpful during long recovery walks (especially if the grass is rather tall), to see its location--and not lose it!--from the decals glinting in the sunlight. Also:

3D "printing houses" such as Shapeways (see: www.shapeways.com ) print objects in metals--including precious metals--as well as plastics (and even porcelain), so it may be possible to make reproductions of the Centuri angled jet deflectors as well as the plastic launch pad parts, and:

Looking at all of the posted Centuri blast deflector pictures (I prefer their angled design to Estes' disc deflector, too, because burning propellant bits don't "splash back" onto the rockets), it looks like its design might have been inspired by a stamped metal snow shovel, which is similarly-shaped and also has the stamped-in longitudinal "stiffening ridges." I wouldn't be surprised if Leroy Piester, when looking for a contractor to produce his jet deflectors, went to a metal-stamping shop and was told, "Something like a small, stamped-metal snow shovel could be made in one operation, out of one piece of steel." Depending on the set-up costs, this might also be a viable option for having new ones made today...

Blackshire,
Thanks for the compliment earlier! Faith in our Creator is vitally important to me. I believe it is only because of Him that we can live and move and have our being!

BTW, Rocketguy101 and I are collaborating together on the 3D model of the ID-65 Blast Deflector for the Centuri Power Tower. Hopefully, we'll have some good drawings for it soon!

Kind regards,
Jeff Jenkins
aka: Faithwalker
NAR #46879

Of course, some additional GSE choices, if you want to go even more retro, might be the EFC-44 Lectra Line controller (https://www.ninfinger.org/rockets/c...i65/65cen6.html) or the EFC-66 Ignition Control Panel controller (https://www.ninfinger.org/rockets/c...65/65cen54.html). *Updated the broken EFC-66 link, so it should work now.

Kind regards,
Jeff Jenkins
aka: Faithwalker
NAR #46879

You're welcome; I discovered the same thing, thanks to shamanic drumming!

Good--if the current 3D metal printing technology is up to producing a sufficiently-durable deflector (it may be), those drawings could be used (either as-is, or by using their graphical co-ordinates) to create 3D printing files for them. The drawings--as they are--could also be used by a metal-stamping shop to set up the tooling to make them.

[QUOTE=Faithwalker]Of course, some additional GSE choices, if you want to go even more retro, might be the EFC-44 Lectra Line controller (https://www.ninfinger.org/rockets/c...i65/65cen6.html) or the EFC-66 Ignition Control Panel controller (https://www.ninfinger.org/rockets/c...65/65cen54.html).

One more retro GSE choice might be the elusive EFC-88 Heavy Duty Ignition Outfit: https://www.ninfinger.org/rockets/c...64/64cen38.html

Kind regards,
Jeff Jenkins
aka: Faithwalker
NAR #46879

Your second link won't open, but yes, that old metal-cabinet Centuri Lectra Line controller is durable and very easy to replicate. Even the plastic Lectra-Line 1 and 2 could be replicated by 3D printing or resin casting, using RTV rubber molds. I like the original metal-cabinet one just fine, though (but if someone made the later ones, I wouldn't turn my muzzle up at them). ALSO, the flat angled blast deflector on the simpler, "block o' wood" launch pad (on the same catalog page as the original Lectra Line launch controller, in your first link above) would be *very* easy to make--just cut out a properly-sized rectangular piece of sheet steel, then bend it in the correct places and drill (or maybe punch) two holes to fit over the launch rod!

The EFC-88 had 25' firing leads and 5' battery leads--for model rockets, heavy-duty indeed! It too would be easy to replicate.

Sorry for the broken link. (*Note: EFC-66 Ignition Control Panel link in post #26 above has been corrected.) Here's a different link for the EFC-66 Ignition Control Panel: https://www.ninfinger.org/rockets/c...68/68cen66.html

Both links should work now.

Kind regards,
Jeff Jenkins
aka: Faithwalker
NAR #46879

Anybody happen to have copies of the Operating Instructions for any one of the following:
the Centuri EFC-44 Lectra Line Controller, the EFC-66 Ignition Control Panel Controller, and/or the EFC-88 Heavy Duty Ignition Control Unit? If so, could you post on YORF please to document them? Thanks!

Kind regards,
Jeff Jenkins
aka: Faithwalker
NAR #46879

Thank you--that one works! It also jogged my memory regarding a discrepancy with the Semroc reproduction Astrobee 350's fins, which are obviously under-sized as compared to the original Centuri kit's fins.

see post #30 in this thread

I don't know for sure--due to its resolution--if this is a different type of flat Centuri blast deflector, or a variation of a 1960s-type one instead, but on page 53 of their 1972 catalog, under the "Launcher Accessories" heading (see: http://www.ninfinger.org/rockets/no...a/72cen052.html ), there is featured a flat, angled blast deflector that appears to be designed to slide over the cross-member of a sawhorse (for a multi-pad rack launcher). I can't see it quite clearly enough at that resolution, but it looks like *this* http://www.ninfinger.org/rockets/ca...68/68cen26.html "Launcher Assembly" pad's blast deflector, in the 1968 Centuri catalog. They appear to differ in that the "sawhorse" one looks like it has upward-angled "wings," while the 1960s one is a flat rectangle of sheet steel, bent "forward to back" in two places.

What you picture in the two ninfinger links are definitely different blast deflectors.

Thank you. The drawing in the 1972 catalog definitely gave that impression (of being different from the 1968 one), while the Power Tower one appears different from both. The 1968 one (on the "block of wood" launcher) looks like the easiest one to replicate.

Glad I was able to help.
I also agree that the "Power Tower" pad one is also different.
When the Power Tower was produced, both Centuri and Estes were owned by Damon.
The Power Tower was a clone of the Estes Porta Pad.
The only thing that differentiated the two was color and blast deflector shape.

Another kid at school in Georgia who was into model rocketry had one; I definitely preferred their angled deflector to Estes' disc deflector, which kicked back finish-marring sparks unless the rockets were elevated a little way above it with a clothespin or a spent motor.

The Power Tower was not just a clone. They were made in the same mold. Mine have identical mold lines and marks.