Epoxy
 

Can anyone recommend a reliable brand of epoxy? I prefer log setting, one hour type. I recently experienced my second failure in the past five years or so with a particular brand to cure fully or at all.

Thanks,
Bill

RE: Epoxy
 

I usually use Great Planes or Zap. Both are 30-minute, but I've never had a failure.

I've recently been using a slower-set epoxy paste which is also excellent called Epo-Grip #30 paste

RE: Epoxy
 

I have used many brands sold by the LHS with total success. This includes Pacer Z poxy, Bob Smith, and NHP epoxy. I normally use either five minute or thirty minute. The key is making sure your porportions are correct, part A vs part B. Also make sure you mix, (stir) well before applying it to the durface. Also apply to both surfaces then clamp together. This is not probably you , but years ago a fellow kept having his models literaly fall apart and we could not figure out why untill one day he was doing a field repair. he put part A on one side and part B on the other then just pressed them together without mixing them. I guess he did not have the time to read the instructions on the bottles...LOL
I use the five minute on thingd that are not structial in nature. I always use 30 on parts that are. I normally always use Epoxy on hard wood joints instead of CA. I think it is a stonger bond.

RE: Epoxy
 

I've used the Great Planes for years

RE: Epoxy
 

I prefer the Bob Smith brand. I have never had a failure, however you do need to make sure that it is mixed 50/50 or it will fail. I have used some brands over the years that were not as user friendly and would not set up no matter how close you were on the mixing. I have also used Pacer which is just as good as Bob Smith, however you still need to watch your mixing ammounts. Good Luck, Dave

RE: Epoxy
 

I have been using the Bob Smith brand for some time. I used to just eyeball the proportions with good results but am getting better bonds after picking up a small digital postal scale and carefully measuring by weight then mixing thoroughly.

Tas

RE: Epoxy
 

I have used several brands of epoxy with no problems and I also eyeball the amounts. However, be careful to not mix it in a wax paper cup or on any thing that has a waxy surface (wax paper, etc.).

That will keep it from curing..

Paul

RE: Epoxy
 

Some epoxy has a pot(storage) life beyond which you may have problems. Also be careful of room temperature when applying it. If the room is too cold this can cause problems.

RE: Epoxy
 

Hi Bill,

I've recently used 6min and 30min epoxies branded as Tower Hobbies Build-it, ZPoxy brand finishing epoxy, and NHP Brand 12 min epoxy. All have worked pretty well even though I mix 95% on a piece of wax paper. That said, the NHP brand stuff does seem to set up much harder. In a few days they all seem the same.

When you get a "soft pour" where it seems to remain flexible or rubbery its usually the result of too much hardener. The only time this seems to happen to me is when I mix a large batch in a plastic cup where it is difficult to get precisely 50/50. When I mix on a piece of wax paper I can more closely eyeball the two puddle sizes before swirling them together.

Hope this is helpful,

Clay

RE: Epoxy
 

Mixing in a container with a wax lining (or waxed paper) is asking for trouble. The wax will often inhibit if not prevent a good cure. You can also get in trouble by trying to thin the epoxy with alcohol. I know some get by with it but also have seen many where the cure will never harden or cure well. Best to use a finishing epoxy or it you must thin, use acetone. Best is to use no thinner at all and gently heat the joint if you need better penetration or spreading.

RE: Epoxy
 

Mixing is one of the key things you can do with the epoxy, I buy bags of cheap acid brushes at Harbor freight and use them instead of A stick. This time of year I also have to heat the epoxy up to get it thin enough. I mix it until it turns A white?? Light color, sorry, that color blind thing. Anyway, after using the brushes I discovered how much better the stuff would mix. As to brands?? What ever my LHS has in stock works well for me. On fire walls and any of the thicker woods I use A small dental burr {drill} and put holes in the sides so the epoxy has someplace to flow into for that added hold. On fire walls I also use tooth picks to pin my work. So far no problems with anything falling off. Wonder if it works on hair???:D

RE: Epoxy
 

I would have thought the more hardener to better and more certain the cure. Live and learn.

Thanks,
Bill

RE: Epoxy
 

Good idea increasing the gripping surface with a dental bur. I never thought of toothpicks for holding work.

Thanks,
Bill

RE: Epoxy
 

Thanks, I've been very happy with great Planes products.

Bill

RE: Epoxy
 

That's funny about the part A and part B application. It reminds me of a story that a biker friend of mine told me. An older friend of his told him about the time he stopped at a stop light and forgot to put his feet down when he stopped. Time to fire-up the old Impala?

Bill

RE: Epoxy
 

Thanks also for the Zpoxy finishing epoxy tip. I was recently thinking about who might offer such a product. I've heard about guys mixing denatured alcohol, lacquer thinner or acetone with regular epoxy to make finishing epoxy. I'm nervous about chemical compatability.

Bill

RE: Epoxy
 

This is a tip I want to pass on to all of you kind folks who responded to my post. I always eyeball my mix. I have found that using a plastic sandwich bag is a good way to mix epoxy. I squirt equal amounts into one corner of the bag ( I usually cut off the zip lock strip for easier handleing). It's easy to visually see if you have fairly equal puddles of A & B. I twist up the corner of the baggie and knead the mix between my thumb and forefinger until I feel it getting warm. Cut off a very small piece of the corner of the bag and apply the epoxy as though it were frosting comeing out of a baker's bag. You can draw a very neat bead. Additionally, you can set the bag aside and periodically check the residue in the bag for proper cure. Especially handy if you have a "blind" epoxy application and can't get back to it to check for set-up. I haven't tried it for very large applications but they make very large freezer bags nowadays. Don't use really cheap sandwich bags, I've had them burst brfore.

Works for me.

Thanks to everyone and happy holidays!

Bill

RE: Epoxy
 

I have a stack of index cards 3x5 and a bag of bamboo skewers break off a piece and mix by eyeball and I know it is set by the left overs on the card and throw it away when done!!!!

RE: Epoxy
 

west system is the best stuff i have used.

RE: Epoxy
 

most brands work well, but all have a use by date, and you can tell by the colour of the hardener, it goes a darker colour. I use the cheap medicine cups for mixing my epoxies, that way you can get a fairly accurate mix. Again avoid to much hardener, it will not set it any faster, and may take forever to set and harden if at all. To speed up setting use gentle heat, and you can warm your mix up by putting your glass etc in a bowl of warm water for 3 min. Dont use expoxies below 10 degrees C, that will adversely affect curing too

RE: Epoxy
 

During the summer my wife and I eat those Pudding cups deserts, guess what I use to mix in.

RE: Epoxy
 

heres what i mix on for small batches of glue.. I take an old catalog, like last years tower catalog, and I smear titebond type glue on all three edges that aren't bound. work it in a bit, then let it dry a day, then I cut it into 4 equal parts on my bandsaw, now I have four glue pads that I can mix on, just tear the top sheet or two off and toss them. Also a good way to mix small batches of epoxy is to make two equal lines of glue next to each other, but not touching, that way you can compare easier, and its not curing yet...

I used to mix in the waxed cups and never had a known problem with it, but I quit before I did have a failure...

RE: Epoxy
 

I agree with RV man. You won't find a better epoxy than "West System". Any yachting store has their products. You can buy a little kit that includes all the stuff necessary, but I would buy the quart can with the pump and the standard #205 hardner. The pumps are extra and come with the correct one for each of the 2 cans. No measuring, just pump an equal number of times from each can. I buy it in gallon cans because we use it for all kinds of work on our racing sailboat. They also have several filler powders available depending on whether you want strength or easy sanding. #404 for strength and #410 for ease of sanding. It is not as easy to sand as you would like, so I don't use any of that for fairing on models. For small jobs I use regular 30 minute epoxy, but for things like applying fiberglass cloth for a wing joint, West is best.;)

RE: Epoxy
 

Epoxy is a polymer, means when you mix it its creating chains of units, and if the amounts are not mixed well there will be unsatisfied pockets of one ingredient.

That also means that its starting to create those units into chains as soon as one ingredient comes in contact with the other.

Before I mix I put the two bottles into hot water from the faucet, it makes them flow much easier from the bottle, its something I learned here on RCU.
And if you put the cup with the mixture in icy water it slows and extend the working time.

I write the mixing time on the cup before I pour the resin and hardener into it, its important because that’s how I manage the whole process without getting into cured epoxy while working.

I mix it also on tower catalogs, that’s what they are for.

as for brands i use tower, will try GP next, they are all the same, i choose by the comfortable package.
towers epoxy work time wasn't reliable, NHP was but i cannot find them any more.

Alex

RE: Epoxy
 

I have gone to West epoxy for everything. I use the Small Batch epoxy scale for small quantities.

http://www.jamestowndistributors.com...stem+320+Scale


I use West system 105 epoxy resin and several west system hardeners listed below depending on application

Fast - 205
Slow - 206
Special coating - 207
Extra slow - 209


I also use their fillers

410 Microlight filler for fairing
404 High -denisity

A good place to get this stuff is www.jamestowndistributors.com

I also use Plexus MA310 for plastic to anything bonding. Works well in my model sailboats that are made of styrene.