Not your ordinary epoxy thread...

[prfesser]

Regarding "different systems": an epoxy resin (e.g. West 105) that has three different hardeners is ONE system. West 650 is a different system, with a curative specifically for it. US Composites thin epoxy is one system (3 hardeners), and their thick epoxy is a different system; doesn't use the same hardeners. Bob Smith is pretty much one system whether 5 min, 15 min, 2-hour.

Ignore quick repairs with 5-min stuff. Ignore anything you tried once for part of a construction and didn't use again.

Seems a lot of users make recommendations based on use of just one or two systems. It'd be interesting to see how many people have actually tried several systems to examine differences.

FWIW here's my experience, all of which have been used to build at least a couple rockets, make or laminate several tubes, do honey-do tasks around the house, or for a particular repeated use such as potting nozzles, casting small parts, coatings. Some are no longer available.

West 105
Fibre Glast (long ago; don't recall the resin but I suspect it was just relabeled West 105)
System 3 basic
Mr. Fiberglass laminating
US Composites laminating
US Composites thick
Bob Smith
3rd party no-name clear casting/coating epoxy
DER331 resin with miscellaneous curatives
EPON815C resin with miscellaneous curatives (DETA, diethylenetriamine, cures it fast.)
Devcon (off-the-shelf 1:1 mix)
PC-7 paste system
Hysol thixotropic resin (dunno the number, came from Firefox)

 

[cls]

WEST 105 , Bob Smith, Aeropoxy, TAP epoxy, TAP vinylester.

What about Proline, where's that from? And what about JB Weld?

(edit, used those two with good results)

 

[Antares JS]

West System, Bob Smith, JB Weld

Different epoxies I use for different things.

JB Weld is for bonding metal.

Bob Smith is general purpose and indoor use, since it's thick and easy to mix tiny amounts.

West System is for large rockets, fin fillets, and outdoor/shed/garage use only, since it's hard(ish) to mix small amounts of it, and it's runny and messy. I usually take advantage of its runniness to get it in spots that can't easily be reached, and for fin fillets since it will settle into a smooth fillet without having to be touched.

 

[Pinetree]

ZAP (5 min) and Bob Smith (15 min).

 

[Rschub]

I haven't seen MGS yet.

 

[watheyak]

I've used both West Systems and Aeropoxy both as laminating resins and structural epoxy by adding silica and flox. I very much prefer Aeropoxy of the two. Cures stronger and harder than West.

I've also used Cotronics 4461 as a high temperature laminating epoxy. It's clear and strong, but a pain to use. It's not technically a laminating resin.

Recently I used Loctite EA-9394 as a high temp structural epoxy. It's great. Super strong and decently sandable, but expensive.

 

[prfesser]

I haven't used JB Weld much except for minor repairs. But for those who have used it extensively to build a few rockets, count it as a system.

I was not aware of Proline. From the web it appears mostly for epoxy coatings. Just looked it up; Wildman has a 1-quart set of 4500 for high temperatures, meaning about 350 F. Sounds good for mach projects.

MGS...I don't even know what it is.

Please...If you want to tell which systems you've used in the comments, that's absolutely fine. If you've used it, count it. If it isn't on the list I've used...count it. Main point: I and probably others would like to see how many different systems you've used, and whether one or more that is clearly superior or inferior. And how is it better/worse? Too thick? Too slow? Too fast? Hard to sand? Too doggone expensive? Doesn't sand well? Whatever.

In particular, there seems to be a heavy preference among rocketnutz for Rocketpoxy and a couple of others. If you've only used Rocketpoxy...doesn't look like an objective decision. Those who have used Rocketpoxy or some other epoxy that gets raves, and have also used several other epoxies, please let us know why Rocketpoxy/JBWeld/BS/super-cheapo-epoxy/super-expensive-epoxy is so much better than the others you've used.

 

[Steve Shannon]

Aeropoxy laminating epoxy, Bob Smith (and relabeled flavors), JB Weld, and West Systems.
My favorite is Aeropoxy unless I’m in a hurry or working on something small.

 

[Pinetree]

"Something small"

That's a good point. At this stage of the game I'm only using epoxy for the occasional fiberglass rocket, fin fillets, and centering rings.

 

[jsdemar]

US Composites almost exclusively for 10+ years. Started with West Systems. That's my "2" vote. I use JBWeld (original) for a few things.

 

[Rschub]

https://www.aircraftspruce.com/catalog/cmpages/mgsresin.php
I did vote.

 

[cls]

please let us know why Rocketpoxy/JBWeld/BS/super-cheapo-epoxy/super-expensive-epoxy is so much better than the others you've used.

I use JB Weld on MMT retaining hw, like Aeropack, and Estes. Mostly because of folklore and superstition about Tg (temperature the resin gets liquid again) and the supposed 200F motor case temperature.

It's always worked. But I have no quantitative data about it.

One thing, I have several 54mm Aeropack retainers that I'd like to recycle. someday I'll put them in oil on my dad's hot plate and put it up to 300F or so.

 

[Steve Shannon]

One thing, I have several 54mm Aeropack retainers that I'd like to recycle. someday I'll put them in oil on my dad's hot plate and put it up to 300F or so.

I use a hot air gun and heat the retainer until it smokes. Then just pull off the retainer body.

 

[cls]

I use a hot air gun and heat the retainer until it smokes. Then just pull off the retainer body.

Ok, I'll try that too. Thanks!

Mostly I was concerned about getting the stuff out of the ID grip rings, or whatever we call it

 

[DaHabes]

Bob Smith for stuff that needs epoxy but doesn't need the utmost structural strength (e.g., rail button weld nuts).
Rocketpoxy for all external fillets. Easiest to work with, perfect fillets every time. Sometimes on internal fillets.
Aeropoxy for internal fillets if I really want strong structural bonds. Limited to bigger rockets as it's harder to work with than Rocketpoxy.
West Systems 105. Laminating and for epoxy dams where I need to either pour or inject in a tight space.
JB Weld for Aeropack retainers.
Spray Max USC 2K High Gloss Epoxy Clearcoat. Expensive and only on the big boys.

 

[Hobie1dog]

Global Adhesives two part epoxy for me, as being able to load a cartridge into a gun and screw a self mixing tip on the end, and end up with a self-leveling, nice looking very strong fillet, is something I'm hooked on now, and I formerly used this stuff everyday, 10 hours a day, assembling 100 lb subwoofers that moved 5" of travel and never had glue joint failures. Definitely not hobby epoxy.

 

[Greg Furtman]

I've recently switched to TotalBoat High Performance Epoxy Resin and I like it. I'd been using WEST System epoxies for a long, long time.

https://www.totalboat.com/products/high-performance-epoxy-resin

 

[DrJoe]

Global Adhesives two part epoxy for me, as being able to load a cartridge into a gun and screw a self mixing tip on the end, and end up with a self-leveling, nice looking very strong fillet, is something I'm hooked on now, and I formerly used this stuff everyday, 10 hours a day, assembling 100 lb subwoofers that moved 5" of travel and never had glue joint failures. Definitely not hobby epoxy.

Is that the 5 min or 15? Any advantage of the black over clear?

 

[Hobie1dog]

Is that the 5 min or 15? Any advantage of the black over clear?

5 minute. No difference in clear or black

 

[nevadagold]

Bob Smith, Zap on quick projects.

System 3 General Purpose epoxy with medium hardener. Thin, good for laminating. Will flow into small gaps.

System 3 T88 structural adhesive. This is a thick epoxy. It needs a filler to be thick enough for fillets.

Have recently tried Total Boat Thixo and Rocketpoxy. I like the Thixo better of the two. Holds fillet shape perfectly.

 

[John Kemker]

Bob Smith, in the past.

West Systems 105 for both laminating and structural using cabosil

West Systems GFlex

Aeropoxy ES6209 for structural (and I've added cabosil to thicken THAT)

Aeropoxy PH2032

JB Weld for motor retainers

 

[SkyFire]

For structural and fillets;

 

[JohnCoker]

Bob Smith, West Systems, AeroPoxy. I also use JB Weld frequently, but only for metal bonding or high-temp applications.

 

[John_461]

Loc-Tite (twin tube syringe)
JB Weld
Bob Smith
RocketPoxy
West Systems 105/205
Epoxy clay
Generic laminating epoxy bought off Amazon (mostly used for sealing wooden beer mugs)

 

[waltr]

JB Weld - motor retainers
Bob Smith, 5min or 30 min - construction, laminating, FG
RocketPoxy - fillets

 

[techrat]

I have used:
JB Weld -- usually for bonding metal items, but have started using it for retainers on rockets
Bob Smith -- for Mid Power rockets
Harbor Freight Epoxy -- for quick repairs since it's usually 5-minute epoxy
"FiberGlass Resin" comes in the metal can at Home Depot where you also buy the fiberglass cloth -- and includes a tiny squeeze bottle of hardener
I've also used "epoxy putty", but only for automotive projects

 

[JohnCoker]

"FiberGlass Resin" comes in the metal can at Home Depot where you also buy the fiberglass cloth -- and includes a tiny squeeze bottle of hardener

Are you sure this is epoxy? If the hardener is as thin as water, it's polyester resin. That hardener is quite toxic and the result is weaker than epoxy. It's used a lot in the boat industry because it's cheaper, but has to be handled carefully: MEKP is a severe skin irritant and can cause progressive corrosive damage or blindness.

 

[troj]

Fiberglast, West Systems, AeroPoxy (both adhesive and laminating - not sure if they're different or not), Bob Smith, JB Weld, epoxy clay (for fillets - I don't care for it)

-Kevin

 

[techrat]

Are you sure this is epoxy? If the hardener is as thin as water, it's polyester resin. That hardener is quite toxic and the result is weaker than epoxy. It's used a lot in the boat industry because it's cheaper, but has to be handled carefully: MEKP is a severe skin irritant and can cause progressive corrosive damage or blindness.

Soooo.... you're not supposed to drink it? Yes, it's polyester resin; but I've used it on rockets. My "Big Daddy" (see my avatar) was coated in it, tube and fins, and it turned out to make the little rocket much more durable than stock. I'm quite pleased with the outcome. You can use this stuff in place of epoxy. Maybe not for HPR, but certainly for MPR.

And as it for it being toxic, well, it hasn't killed me yet. But I commute on 2-wheels, so epoxy is likely to be the least dangerous thing I deal with.

 

[4regt4]

Bob Smith: Quit using it, as it's the only epoxy that has failed me. It's too brittle. I had a fin break off, it was the epoxy that broke, as both pieces still had epoxy adhering to them. Never have had this happen with JB or Rocketpoxy.

JB regular ("steel") Motor retainers

JB 5 minute: Love this stuff. Easy to dispense out of the twin syringes, and it cures *very* flexible. So there is some give on impact. I use it a lot on LPR and some MPR for motor mounts and fin fillets where I don't need a big fillet - i.e. for small fins. Also use it to initially tack on TTW fins, where I'll come back and do internal and external fillets with another epoxy.

Rocketpoxy: I like the glue itself, but I avoid using it because I have difficulty dispensing/measuring it. Put a big glob on the scale. 20 grams, OK. Pull a glob of hardener out of the tub, plop onto the scale, crap. 24 grams. Try to get 4 grams of the resin out, and either over or under shoot. Rinse repeat. Hate it. But once mixed, it is one of my favorites.

T-88: My new favorite. It's fairly thick, but I add silica in varying amounts to go thicker or thixotropic as needed. Easy to dispense and measure. BIG problem is the long set up time. About 3 hours before it can be reliably handled.

Hans.

Edit: Forgot..... FixIt epoxy putty. Often on the threads of screw eyes to form a large fillet and to seal the threads from corrosive damage from black powder residue.