How to coat a tube with CA?

According to David Erbas-White :

CA seems only useful if you can get the tube to soak it in. As a surface treatment it's not very good.

We only put CA on the ends of the tube, simply letting the raw tube ends wick up whatever it can.

Especially with paper-wrap facing, you're not going to get much CA soak on the main part of the tube.

For full tube reinforcement, we first scuff-sand the tube and then apply West Systems epoxy using a plastic scraper. With or without glass depending on how strong we want.

With a BBQ-motor lathe, the results are awesome, _without_ any sanding of the epoxy.

So, the primary reason for soaking the outside of the Parachute Cup (BT60 Coupler) is as Joel stated:

"You will find if you need to sand the inside for any reason (piston perhaps?) it mades a sandable surface that doesn't have those 'frizzies' like after sanding plain cardboard."

You need to sand this down so that it slides very, very easily within the upper BT60 tube. Coating the first 1" of the BT60 upper tube will also allow sanding and will strengthen that section since it will see a lot of use with the three different bottoms and the exposure to ejection gases. It may need sanded after a number of flights as well and so CA'ing it makes this easier and stronger.

How I soaded the BT60 Coupler was with my $1.00/4-pack CA from the Dollar store and ran the tip of the nozzle back and forth, turn, back and forth, turn, etc. then stood it on it's end on wax paper to dry. I sanded with 400 grit and did it again (takes much less CA the second time). Sanded until I had a smooth fit.

Nick

Some of you guys must buy CA by the pint.

-- Carl D Cravens ( snipped-for-privacy@phoenyx.net) Wichita, Kansas, US -- Read my model rocketry journal at

Not the pint, but usually 8oz bottles. I also use it on the balsa fins. Doesn't really fill, but makes them stiffer.

Joel. phx

Not HPR, but I've used CA on the old Apogee BlackShaft phenolic and the older CMR phenolic. Works fine.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

What I usually do is squirt a small puddle of CA on a plastic lid (pringles, cheese, butter), then stick the end of the tube inthe puddle and let it wick up the paper. For larger tubes I'll roll the tube end to coat the whole thing instead of making a 2" puddle.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

I wish it was available by the pint! I buy it by the 2 ounce bottle, since that's the largest quantity I can find.

Since it doesn't have infinite shelf life, and my rocket building is pretty intermittent these days, a big bottle seems to end up with part of the contents solidified in the bottom before I get to using it all.

-dave w

Bob,

That's the next to last step.

The last step is trying to remove your pants after a drip that you didn't notice has soaked in and attached them permanently to your leg (or other more tender parts).

NOTE: Acetone and other CA solvents leave large red marks on your leg, and usually doesn't get all the CA out of the pants. Place a paper towel across your lap before starting.

I also find that using finger cots (rubber "gloves" for a single finger), works very well for spreading the CA inside a tube. Just look for "Non-Powdered" brands, the corn starch/ baby powder on the "Powdered" brands acts like a catalyst to the CA and can set it off with great smoke and heat.

Bob Ellis

Sounds like an interesting story behind that bit of data :)

BTW, holding the tube horizontal, I put in the thin CA, then roll the tube around, then finish spreading the CA with a Q-tip which also serves to soak up the excess thus preventing a bump which will have to be sanded out later.

But the Q-tips will smoke. That kinda makes the process a little more interesting :)

Doug

WOW!

Did anyone else notice that this thread was 34 responses long and not 1 mention of ANY of the usual crap to drag it OT? Actual information, from many respondents and all completely civil. Who'da believed it???

AMAZING!!! Randy

P.S. Going outside now to see if the ground is frozen.......

Well, until now, anyway...

David Erbas-White

P.S. While I often comment in threads in both an on-topic and off-topic manner, I at least try to make sure that any threads I initiate are on-topic. I'm pleased with myself for this one, because the number and variety of responses make me feel like less of an idiot for having asked the question in the first place...

It would be nice if it could be the rule, instead of the exception.

Randy

I meant that for ALL of us on rmr. It IS nice, when people are courteous instead of aggressive.

Good thread.

Randy

Welcome to "HOTEL CALIFORNIA"

That's what I do, too. It doesn't waste CA like the 'dip-it-in-a-pan' method.

Right after squirting the CA into the tube, I smear the CA around to cover a large area evenly and to prevent bulges from building up.

I use my finger to do the spreading, protected by a piece of cheap crinkly plastic grocery bag. Unlike Q-tips, the grocery bags won't stick to the tube if you move too slowly. And I have never had one get hot or smoke like some people have when using powdered finger cots.

Like Nick, I use SuperGlue brand in the 0.11 oz yellow bottles from the Dollar Store. It's the cheapest stuff I've seen, and the small bottle means they get used up before they go stale and solidify.

-- Bob Cox

Most of the cheapo stuff is the gel stuff which won't soak into the paper. You need the water-like thin stuff. There really is a quality difference between the stuff I find in mass market stores, and the stuff in hobby shops.

The ONLY decent CA I've ever found outside a hobby shop was in WalMart of all places. Small white bottle with a red label on it. On one of those clip strips, either in the hobby and/or hardware departments. I wish I could remember the brand, but the bottle is at home. Under a buck, small enough for the range box, and cheap enough that I'm not POed when it turns into a rock.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!