6" ARLISS Frank-Can-Stein

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cherokeej

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I'm bored. So I'm putting this here. If it's going up, it's gotta go somewhere.

In what will probably be short bursts, I'll document the build of a Frankenstein ARLISS-M. Going to be made mostly from resurrected parts, on the cheap. If that's possible. (Gotta be. I'm retired/disabled. That's spelled u-n-e-m-p-l-o-y-e-d.) Got a/f tubes, nosecone, couplers... all donated. Got a couple of accelerometers being generously added to the donation pile by a very good friend, too.

Got a nice chunk of FWFG a/f with the internal fin can already installed, and mounting holes for the fins already drilled. This booster section a/f is well used, but will fly again. Got a big bag o' fins. Some new, most used. Think I'm going to give the new ones to my buddy, and install some reworked, used fins on Frank-Can-Stein.

First order of business, the motor mount and motor retainer. Located a 24" hunk of 98mm phenolic wrapped in 4 oz glass in the "old tubes" box. That'll work. Could order plywood c/r's and an Aeropack retainer, but where's the punishment in that? Already own a lathe, a duke-load of tooling, and got a big ol' pile of al-you-mini-uhm...

Start with some 6061 bar stock...

DSCN0324.jpg

Add a generous portion of turning perfectly good aluminum into curly, double-edged razor blades...

DSCN0326.jpg

And come up with a forward centering ring, a 98mm motor retainer with knurled, threaded nut, and a thrust plate.

DSCN0328.jpg

Lousy pics cuz I'm a lousy photog using a cheap camera.

The retainer is an interference fit into the recess in the thrust plate. Heat one, freeze the other, put 'em together, one piece. But being a belt-and-suspenders kind of guy, I'll install a few screws inside, just cuz they'll fit. And this is an ARLISS. No messin' around with ARLISS.
 
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I'll be following this closely - I hope to build something for ARLISS with my kids within the next few years.
 
I'll try to do a decent job of documenting the build for you, Dan.

We would very much welcome some new blood at ARLISS. It sure is fun. And you can't beat having someone walk up and say "Here's a free M. Fly it for me."
 
Well, the thrust plate and motor retainer are complete. Eight more holes to be drilled and tapped in the thrust plate and upper centering ring for installation in the a/f tube, and the motor mount is done. Pix to follow.

Further inspection of the (well used) lower airframe assembly reveals that several of the holes in the internal fin can are stripped. Not all, but enough. Options are to replace the internal fin can, re-drill and tap at 10-32, or J-B Weld some tee nuts inside the can. Going with the tee nuts. Pushing that can out of there would be a real PITA, and I don't want to mix screw sizes on this build. (All the a/f assembly screws are to be 8-32 BHSHCS. Makes working on it in the field easier.) But with the oxidation in that can, I'll need to clean it up a bit first. I've got a buffing wheel I can put on an angle drill, and get in there to clean it up. I'll see how that goes. I'm not going to lose any sleep over a little aluminum oxide.

Out of the large bag o' fins I received, I found two full sets that are straight and usable, two fins that are twisted beyond repair, and several more that could use a little TLC from an anvil and a ball peen hammer. So I'm good on fins. I gave the full set of brand new long fins that were in the bag to my two buddies. Their ARLISS birds use the longer fins, and it's good to have spares on hand. That's the advantage of putting it together with screws. If it swings under chute and bends the crud out of a fin or two, you break out the screwdriver and fix it.

More pix later.
 
Can you use PEM nuts, or is there not enough material around the hole to support them?
 
Yes I could. But that would probably require removal of the can from the a/f tube. I don't want to do that. And I've got a big bag of 8-32 tee nuts on hand already... It's just easier. Laziness is the mother of invention.

Eight 2-56 stainless flat heads holding the retainer to the thrust plate... Yeah, they're tiny. But between them and the press fit of the retainer into the thrust plate, it'll hold.
Of course the plate looks like hell and has extra holes. It came from the scrap bin. (And since it's hidden, I didn't bother facing that side of the work piece.) This is a Frankenstein rocket. Gotta sew together dead parts and make it live! BWAAHAHAHAHAAA!

DSCN0333[1].jpg

A shot of the tail end of the tube... EXTRA crusty can. Yuk. Need to clean that mess up.

DSCN0331[1].jpg

Also note the short section of coupler that is glued in place behind the can. That's why I made and screwed a ring to the thrust plate. The bottom screw for each fin will hold the thrust plate in place.

DSCN0335[1].jpg

I originally planned to section out that mounting ring, and leave just the four "ears." I may still do that, but for now, I'll look to possibly installing the lower rail guides into that ring. Two sets. 10's on one side, 15's on the other. AeroPac has both size rails at the cell, so if it's busy, it won't matter which pad is available when I get out there.

The ring of holes around the bottom end, and most of the other holes that are already in this a/f tube, will be filled with a dab of J-B Weld. If'n I don't need 'em... I'm a-gonna plug 'em.

Once I get that can cleaned up and the fins on, I'll install the mmt and post a shot of the assembly.
 
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Holy moly... Resurrect an old thread. Been busy with GSE for the club, and a nasty go-around with the flu. Not good.

Got to thinking about Chris' suggestion of pem nuts for the can. Hell of a solution. So I made a tool similar to a Detroit liner puller. Put it in there against the ribs of the can, and push like you mean it.

Lifted my body off the ground, and that can didn't budge. And while I'm no line backer, I'm not small. So much for that idea. Back to the tee nuts. 8^(

I'll get the fins on, and put up some more pix if and when my kid brings my camera back. 8^(
 
James, sorry you are bored. It has been a rough winter for flying.

I have some parts that you may be able to use - PML nose cone (2 actually), a short internal aluminum fin can cage (From the ARLISS rocket Jackson augured in - but I think it is in good shape but needs some cleaning), some 6" to 98mm centering rings and bulkheads (all .5" from PML). Probably some more stuff as well. I would be happy to exchange them for some machining work. I am going to need a new ISC at some point.

BTW, my two stage you LCO'd for me at ARLISS was not my Mongoose stack. I scrubbed that plan after getting a nice little ESD pop one morning. The thought of head end ignition and ESD kind of scared the @#%#^#$^# out of me . So I and went to FG after that. Full Bore Linera Panic...RIP somewhere in N. Nevada. The Mongeese are still safe.

Let me know if you can use the material and if you are barter friendly. But I can go cold hard cash as well.
 
JD! My brother from another mother! Short out any SMUD wires lately? 8^)

You didn't use that closure I made? Then I've been bragging on something that wasn't true... 8^(

ESD pop!!??!! We need to talk. Soon. Cuz... Damn!

You already know I'll make you an ISC. You're one of the few people on the short list. Mostly... ARLISS people.
 
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getting a nice little ESD pop one morning.

Tell us more about:
- what happened, exactly?
- how you know it was ESD related?
- what avionics were in use?
- what precautions you took to make sure this wasn't going to happen?
 
No, haven't popped any SMUD lines lately (last 15 years anyway.

Yes, I did use your closure. It worked beautifully on both flights I used it on.
 
To clarify the ESD pop further: I was beginning a 2 stage project with my Mongoose 75 as the sustainer and the Mongoose 98 as the booster (N1000 to M685). I had planned on using head-end ignition to light the sustainer. I got the "ESD" event one morning as I was beginning to work on the sustainer. As I reached for the airframe an arc between my finger and the CF air frame was both seen and felt.

There was no electronics, e-match, BP or motor involved.

That is all there was to it. It was just the air frame laying on my work table, nothing else.

Am I absolutely sure it was ESD? No, but don't know what else it could have been. I took no precautions to prevent this event because I never had anything like that happen before (or since).

I flew two flights of the eventual Fiberglass stack using head-end ignition with no other incidents but took drastic precautions to prevent any problems.
 
Thanks for the clarification, Jonathan. Had us worried.

So you did use my closure. I can brag some more. 8^)

When you absolutely MUST get it lit...
 
Try this again... First time, this wonderful windoze 10 froze up.

Fins are on, mounting holes for thrust plate tapped, need to turn a mounting ring for the coupler, and add rail guides. Then on to the av bay.

DSCN0337.jpg

Yeah, that's not the only screw that's loose around here.

It has to come apart and sit in pieces until summer anyway. Can't paint during the monsoons.

Another job is going to take priority over the next few working opportunities. Got a couple of bays to build for a friend's full scale Arcas.
 
Looks a little hefty...how much does it weigh? I was looking for a boat tail for my ARLISS rockets a few years ago. Couldn't find anything so used laminated PML bulkheads. They have gotten a little charred and the playa treats them rough.
 
I've been thinking about my nice, custom aluminum getting all charred up by the back-blast.

We've been using a Spray-On product on motor cases for a while that seems to help keep the nasties off. Guess I'll try a few applications of that stuff. Better than nuthin...
 
Fair warning... This one's coming back around.

Made a mounting ring for the a/f coupler. Yet to be drilled and tapped.

Got some work done on the av bay. Upper bulkhead is turned, and I turned a spacer ring to go in the front, to house the carrier tether and ejection charges. I'll put up pix when I get 'em. Next in the chuck... The lower av bay bulkhead. Then the lathe work is done, and it's on to the drill press.

Pix when the daughter brings my camera back.
 
Well, here's a dis-used thread...

I finished the bird. It came out too tall and too heavy. I have just about a month to go. One option is to chop the booster and coupler and make a new forward centering ring to fit the coupler ID. That would shorten the rocket by a good foot, and take a pound or so off the weight.

Another option would be to shorten the recovery tube, put the chutes in the coupler, and make a bulkplate for the bottom of the coupler to keep the chutes from getting sucked too far down inside the booster. That's the easy way. Chop-chop.

84" Rocketman R9 for the booster, 72" TAC-1 from Giant Leap for the upper, each on 20-25 feet of 1" TN. They get cross-packed. The upper chute on the bottom, the lower chute on top, blow the halves, and hopefully they pull each other out. That's the theory, anyway. It worked in the last one I built, about 70 some-odd times so far. Should work in this one. Nomex and charges will go down below. Blow 'em out instead of in.

Now we get to see if a fat old guy can stuff 9 feet of rocket and enough crap for a week at Black Rock into a tiny little puddle jumper. Hell, I'd pay a dollar to watch that.
 
I've been thinking about my nice, custom aluminum getting all charred up by the back-blast.

We've been using a Spray-On product on motor cases for a while that seems to help keep the nasties off. Guess I'll try a few applications of that stuff. Better than nuthin...

Sorry to resurrect the thread, but what exactly is this product?
 
Spray-On brand silicone spray. The can says "Lubricant Q.T.L. Dry Lube." Pretty good stuff. Takes a few applications to season a case, but helps a lot with clean up.
 
Well since this thread is resurrected...

Micro- launch report...

Frankenstein lives!! Test flight on an ALCO M1300 was magnificent. The subsequent payload flights, on M1419's, all went well.

Frankenstein will return next September for more.
 
Spray-On brand silicone spray. The can says "Lubricant Q.T.L. Dry Lube." Pretty good stuff. Takes a few applications to season a case, but helps a lot with clean up.

Do you use that on the inside? I was considering it for some bare aluminum cases, but I was concerned about it burning/doing something weird in the heat...

Is there something special about that brand?
 
Nothing special that I know of... It just works. For me. Your mileage may vary.

We spray the inside of the case, the seal disc, and both closures. The spray doesn't burn in the case. You're still going to have to clean your case, but it's a lot easier than using grease on the liner. After a few applications, we find it helps a lot. Almost fly-and-wipe.

The M1419's... Personally, I like to grease the seal disc, even after spraying it. The White Lightning propellant seems to burn dirty. Greasing the disc makes it clean up a little easier. And at ARLISS, we're burning 1419's all week long.
 
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