Epoxies and unheated shops

Sean Jones

Well-Known Member
I'm curious those of you that have unheated shops like I do, how do you handle glue-up on your knives?

This time of the year my garage hovers somewhere between 35 to 38 degrees. What I've been doing is bringing my epoxy into the house until it's time to glue-up my scales. Then I use a space heater in my garage to keep everything warm for glue up. But it's rather awkward and inconsistent. I've also had a couple scale failures this way as well. Luckily they failed right away and I was able to correct the problem.

So what do you guys do? I'd rather not bring my knives into the house for glue-up. We have five very curious cats that tend to get in the way. If that's my only choice I could close them out of a room for a while, but it would be somewhat inconvenient.
 

izafireman

Well-Known Member
I have learnt my lesson with epoxies and cold temps and so I glue everything inside the house.

In your situation keep the blanks, scales pins etc. in the house until needed so they are up to temp. Then glue up in the garage and place the knives inside something like a cheap cooler box or polystyrene fish mongers box with a hot water bottle inside and several of those cheap gel packs which you can either freeze or heat up water, they heat up great with boiling water. The other option is heat up a fire brick in your house oven, wrap in a towel and stick that in the cooler box. Oh and I would purge the cooler box with hot water first and dry, then that to is nice and warm.

Then once the knives are inside wrap the box in a blanket. Should give you a fair chunk of time for the epoxy to set.

Cant help with the cats I am afraid unless you pay the air fare for me and my dog and she will happily chase them out of your house for you.
:D:D:D


 
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opaul

Well-Known Member
In the winter I keep my epoxy inside. I do heat my shop when i’m out there working so I’ll bring it to the shop when i’m ready to glue up. I’ll bring the knife back in the house to cure.
 

EdCaffreyMS

"The Montana Bladesmith"
An unheated shop can cost you big dollars in ruined glues, and finishes, and wrecked knives. Letting epoxy freeze and thaw a single time will lessen it's hold life by 1/2 or more, and with some, will render it useless.

If your shop is unheated, it's essential to keep and use your epoxies, glues, and finishes in a temp controlled environment. Most will state minimum storage and use temps. The majority of epoxies used for knifemaking recommend mixing/curing at 70F.

If you must keep your epoxies/glues, etc in an unheated shop, an old refrigerator, with a single 100 watt light bulb inside will keep the interior temp about 60F under most circumstances....provided you keep the door close. :)
 

TimGinMN

Well-Known Member
Yeah, Winter is damn inconvenient. I bring all my adhesives inside when it starts to get cold and do glueup inside too. Just have a bin they all get stored in so I only have to grab one thing. I try to do my glueing when my wife is cooking so that masks the smell of the glue... I hadn't thought about making sure the materials are up to room temp - good idea. The cooler idea I like too. Might try it with handwarmer packets. We have plenty of those around.
 

Chris Railey

KNIFE MAKER
It gets cold in my shop, well cold for the south mid 40's at its coldest. The main problem it causes for me in using epoxy is it thickens so much that its hard to get it out of the bottles. Once you mix it, its exothermic so it loosens up quick. My solution is I float my bottles in warm water for a few minutes before I glue up. Works every time.
 

tkroenlein

Well-Known Member
Epoxy in the house until glue up. Mix and glue in the shop, let the epoxy set long enough it won't drip, take it in the house. We need 70F+ to cure epoxy. The left over stuff in the cup is noticeably more brittle if it cures between 50F and 60F as opposed to curing at 70F+ in the house. I use BSI Slow Cure.
 

BossDog

KnifeDogs.com & USAknifemaker.com Owner
Staff member
at least 70+ degrees temp is needed has been my experience. I have glued up some epoxy in a cool shop (less than 68) and it never set up properly even when I heated later to try and get it to fully cure.
 

Sean Jones

Well-Known Member
Thanks for the replies. We have a 'spare' room that has been a junk room that I'm wanting to setup for leather work. I think that will become the glue up station now as well. Closing the door will inconvenience the cats but they shouldn't holler about it too much.
 

Sean Jones

Well-Known Member
An unheated shop can cost you big dollars in ruined glues, and finishes, and wrecked knives. Letting epoxy freeze and thaw a single time will lessen it's hold life by 1/2 or more, and with some, will render it useless.

If your shop is unheated, it's essential to keep and use your epoxies, glues, and finishes in a temp controlled environment. Most will state minimum storage and use temps. The majority of epoxies used for knifemaking recommend mixing/curing at 70F.

If you must keep your epoxies/glues, etc in an unheated shop, an old refrigerator, with a single 100 watt light bulb inside will keep the interior temp about 60F under most circumstances....provided you keep the door close. :)
I don't think it's ever actually frozen in the garage, but it's come really close more than once. Even a space heater doesn't help much when it gets really cold.
Looks like I need to move all that stuff indoors.
 

TimGinMN

Well-Known Member
at least 70+ degrees temp is needed has been my experience. I have glued up some epoxy in a cool shop (less than 68) and it never set up properly even when I heated later to try and get it to fully cure.
I'm not sure my basement is even 68... guess I'll be curing my epoxy on the dining room table from now on. But seriously, I didn't know that epoxy was that picky. I'll have to pay better attention to what I'm doing with glue-ups. Thanks for the info.
 

Sean Jones

Well-Known Member
I'm not sure my basement is even 68... guess I'll be curing my epoxy on the dining room table from now on. But seriously, I didn't know that epoxy was that picky. I'll have to pay better attention to what I'm doing with glue-ups. Thanks for the info.
That's what I'm trying to figure out as well. Our basement, where the spare room I mentioned is, is normally around 62 degrees. I'm thinking I'm going to need an insulated box of some kind.
 

Sean Jones

Well-Known Member
Maybe just hanging a clamp-on work light over it while it cures would be good enough?
That might work. I have a halogen work lamp that gets quite warm.

I'm thinking more insulation in the basement would be better. But I've gotten used to it.
 

Nick Riggi

Well-Known Member
I turn on an oil filled space heater early in the morning morning every day. Set it to 70 degrees and warms to whole garage nicely in just a few hours. If I am working out there that day, I switch it on again a few times.
 

MTBob

Well-Known Member
I've found using a red colored heat lamp lets the epoxy set up nicely, though I'm careful not to get it too hot - just warm to the touch.
Also, BTW, in the winter I never let my shop get below 50, and I'm usually comfortable working in the mid 60s. I feel that high temperature swings can lead to moisture condensation and corrosion on machining equipment .
 
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