Proline or JB Weld?

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RocketRoll

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I'm thinking of buying one of these, and I see that the recommended adhesive is "Proline Black Hi-Temp Epoxy." I've never used it before.

How does this compare to JB weld? And can it be used to tack the fins as well as create the fillets?
 
I'm thinking of buying one of these, and I see that the recommended adhesive is "Proline Black Hi-Temp Epoxy." I've never used it before.

How does this compare to JB weld? And can it be used to tack the fins as well as create the fillets?

What's the use case?
What other epoxies do you have / current use?

In short - yes, Proline is good, and can be used for structural assembly of fins. It's also great for fillets. It's too thick for injecting as internal fillets.
It is also darker than a black hole, and once a smudge gets on your skin on cloths, it will never come out. Almost.

a
 
I just realized I left out an entire sentence... I'm looking to get a Wildman Blackhawk 29.

I've used JB Weld in the past (the original as well as Clear weld)
 
Personally I've moved away from using JB Weld in rocket builds. I think it's too brittle to be useful for our purposes, especially over time.

Proline will work a treat for a Blackhawk 29. Plus IIRC doesn't that kit already come with a supply of ProLine for fillets? You can definitely tack the fins on with Proline as well, it'll just take some time to cure.
 
I use the JB Weld reinforced with steel to tack fins in place and to attach the centering rings to the body tube and attach the retainer. I use PC Super Epoxy to do fillets. I don't have any experience with Proline.
 
I built a Binder Jackhammer a few years ago with just JB Weld except for installing the actual mount into the tubing. Fins, rings, fillets were JB Weld and it fell from 1K after the nylon burned through with no damage whatsoever.
 
Personally I've moved away from using JB Weld in rocket builds. I think it's too brittle to be useful for our purposes, especially over time.

Proline will work a treat for a Blackhawk 29. Plus IIRC doesn't that kit already come with a supply of ProLine for fillets? You can definitely tack the fins on with Proline as well, it'll just take some time to cure.
Have you had problems with parts fracturing upon hard landings with JB weld?
 
Glue comes with the Blackhawk 29....Proline. So no need to figure it out.

It is much easier to mix small amount of JB to tack fins, the Pro for fillets.

That's how it was done for instructions.
 
How about JB Weld just for the Aero Pack engine retention to the fiberglass motor tube? (Metal to Fiberglass)
 
As for Proline, I love making fillets with that stuff! And as stated earlier, wear gloves and be very careful. Rubbing alcohol helps with bonding prep, fillet shaping, and I have found to work really well with clean up. Also a hand sanitizer alternative.
 
I can't find as much information about the Proline epoxy as JB Weld. For example, I live in a colder climate, and am wondering if storing this epoxy in my garage this winter will shorten its lifespan? I will be waiting for warmer weather before using it.
 
Personally I've moved away from using JB Weld in rocket builds. I think it's too brittle to be useful for our purposes, especially over time.

Proline will work a treat for a Blackhawk 29. Plus IIRC doesn't that kit already come with a supply of ProLine for fillets? You can definitely tack the fins on with Proline as well, it'll just take some time to cure.
I had not heard that people were using JB weld for rocket building. I thought its purpose was to weld to metal, not fiberglass or paper tube. I had a crack in my cars valve cover and repaired it with JB weld. Had that car for 18 more years. With no oil leaks from the cover....good stuff on metal....on Fibreglass, wow who knew.
 
I had not heard that people were using JB weld for rocket building. I thought its purpose was to weld to metal, not fiberglass or paper tube. I had a crack in my cars valve cover and repaired it with JB weld. Had that car for 18 more years. With no oil leaks from the cover....good stuff on metal....on Fibreglass, wow who knew.
It's mostly used in high temperature applications. I only ever use it for metal motor retainers, those can get hot, and normal hobby epoxies might soften in that use case. If you're doing high performance, minimum diameter designs, there are better alternatives out there.
 
One correction - do not ever use rubbing alcohol for bonding prep! Rubbing alcohol has oil or other additives to make it not dry out the skin as much. That interferes with bonding. Plus it has substantial water content. Water also causes issues.

High percentage straight isopropyl alcohol will work, and denatured alcohol is better.

Gerald
 
JB weld is what I use for securing motor retainers, and Rocketpoxy for external fillets. For internal fillets, I use aeropoxy from Aircraft Spruce; the stuff takes forever to cure . . . I believe the pot life is 1 hour, maybe longer.
 
How about JB Weld just for the Aero Pack engine retention to the fiberglass motor tube? (Metal to Fiberglass)
Always. I've never had a retainer come loose.
I used to do this (as well as using JB weld for securing aluminum GLR conformal rail guides) and then I stopped using JB and switched to Epiglue for these tasks and I've never lost a retainer or conformal rail guide since.
 
I had not heard that people were using JB weld for rocket building. I thought its purpose was to weld to metal, not fiberglass or paper tube. I had a crack in my cars valve cover and repaired it with JB weld. Had that car for 18 more years. With no oil leaks from the cover....good stuff on metal....on Fibreglass, wow who knew.
I think historically its use case was for metal to composite bonding (like retainers). Then people looked at its temperature rating and started applying it to leading edges of rockets exceeding Mach 1 because they were worried about aerodynamic heating. Then it evolved to "I'm building a high performance bird, best use JB for EVERYTHING on the outside."
 
I use Proline for most of my fiberglass kits.
Allot people like using JB Weld and also over using it. I seen builds, that's all they use to build the fin can.... I think it's a waste.
It' has a place but, not for general rocket construction.
 
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