10 hours epoxy ?

[P.K.Hansen]

Does anybody know an epoxy that has a hardening time of about 8-10 hours instead of 24? I have some that dries in 1 hour, but it only gives you 6 minuts to handle it in, and often thats not enough.Half an hour or so would be fine when putting all the parts together.The fast dryer seems to be more sensitive to heat - how come ?

 

[C L Wilkins]

Quite a few folks are using 5 minute or 30 minute epoxy (also known as 2-ton)on their scales. I am now using a micro-bedding epoxy that Brownell's handles. Once it is set, it is set. I was having an "operator error" a couple of years ago and getting the scales too hot on folders and the epoxy was "letting go". Live and learn.....

The 5 minute epoxy, in my opinion, is useless for knifemaking. It sets up extremely fast (especially when it is warm) and the primary reason for not using it is that it is not waterproof.

The 2 Ton or 30 minute epoxy is what quite a few folks use for scales or slabs. I live near the Texas Gulf coast and in the warmer times of the year, May through September, the 2 ton epoxy will set up in 10 minutes or less. What I did was to place the epoxy in the refrigerator for an hour or so before using it. By doing this, I had more time to work with it before it set up.

Most any epoxy is sensitive to ambient temperature where set up time is involved. Heat will speed up the chemical reaction and as stated above, if gotten too hot, the bond will fail.

C Wilkins

 

[P.K.Hansen]

Seems like what i'm looking fore. I'll try to find that 2 ton epoxy in Denmark.
Thanks Wilkins.

 

[Jeff Clark]

The brand that I used for years is Devcon. I don't know if they use the same name over in Europe. The "8 hour" varieties are pretty standard. If you keep your mixed epoxy in a bowl that is sitting in cold water you can extend your application time. Epoxy is very temperature sensitive. If you want longer working time, work in a cooler room. If you want it to harden faster apply a little heat (it usually gets stronger with a little heat anyway). Always use slower curing epoxy if you can, it is stronger and in particular it will be more heat and chemical resistant than the quicker cure varieties.

I use an incandescent desk lamp to provide a little extra heat when curing epoxy. Be carefull about too much heat though. I have melted plastic when applying a little too much heat.