Looking for an epoxy that can handle high heat.

Diomedes Industries

Diomedes Industries

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Mar 19, 2007
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I am make a project where I plan on bonding aluminum to wood - I need that bond to hold up to at least 800 degrees - perhaps 1000. Is there any epoxy that does this?

Any advice would be great.

TF
 
Well - if you think about the Bow Drill fire - which is the application I am putting this to - the friction needed to get a coal to combust a is about 800 degrees. The friction created at the point of the hearth and the bearing block (the part that I am going to make out of wood and aluminum) is 800 or so degrees (when done right). Oddly the bearing block, almost always made expediently out of wood) does not burst into flames. ;)

I was not clear - so the fault is mine.. I will not be subjecting it to conduction of flame to wood - but convection by means of friction from aluminum to wood. But to adhere the aluminum to the wood - I need an epoxy (if one is possible) that connects wood to aluminum.

Does that clarify?

TF
 
Actually, the wood does burn there, right at the surface where the friction takes place. When you wear through a block it isn't by abrasion on its own. It's also a relatively brief exposure.

As for the epoxy, I'd give Loctite a call and ask them what they suggest. They make adhesives for pretty much every application and given the specific and non standard situation you've got I'd be a little unsure about trusting the usual package information.
 
Make the scales or block out of dense bone or antler and just use bolts or rivets..... no glue. Or, better yet......dovetail bone slabs into front and rear bolsters that have been soldered to the tang...... and bolts. The bone will hold up as a bearing block much better/longer than most woods.
 
TF... I don't think the bearing will get that hot. We promote friction at the drill/hearth marriage but the whole purpose of the bearing is to reduce friction. The aluminum surface will reduce it dramatically but not totally. Have you ever used a rock as a bearing block? They heat up after extended use. I have used a metal key before and it melted the plastic jacket off of it. It will get hot enough to compromise an epoxy bond, which is why I suggested a mechanical connection when you asked me about it. Press fit with some sort of retaining pin.

Rick
 
I did a bunch of research on this a year ago while I was looking for an Epoxy that would hold up during the Tempering process for a guard. I found quite a few that would hold up to 400F the best I found was the slow cure JB weld if I remember correctly. There was a company called Permabond that had a bunch of options but I couldn't stop the sales calls after contacting them...

Edit: none got near 1000F I just looked and JB Weld goes up to 500F. Good Luck
 
I agree Rick - nothing I come up with will withstand the heat. I liked your suggestion - but it added a step (and expense) to the end product. What I am going to do tomorrow is to try an a deep knurling on the outside of the aluminum and a press-fit into the wood. That might be the best 'mechanical' attachment. I thought about the rock concept - which is what I use when I am at home and just want to show someone how to make a bowdrill fire - but I also tried just a chunk of aluminum before - it was too hot to hold after one attempt at the bow drill.

I think I need to just go to some prototypes and see what I get.

TF
 
I wonder if you could design it somehow to limit how much heat made it to the joint. That would protect the epoxy and the wood. Maybe keep the center solid but then some sort of heat sink design around it? I'm not sure how you'd do it to maintain at least some traditional appearance but maybe someone else here with more creativity in these things can solve that.

I've never done this with the "nice" setup, the only bow drills I've used were pure field expedient so I'm a bit lost trying to come up with other ideas.
 
All these parts ( bow, bearing block etc)that's why I much prefer the Hand drill lots less parts. but for a bow drill the "Y" of and antler is great just drill a shallow hole and you are god to go also good for flint knapping, multi-tasker . or are you trying to come up with something you can make a lot of ? glass would be best friction wise glue a piece of glass on the bottom of your block it shouldn't get very hot....
 
Talfuchre said:
... What I am going to do tomorrow is to try an a deep knurling on the outside of the aluminum and a press-fit into the wood. That might be the best 'mechanical' attachment.
Click to expand...

Funny... when I read your initial message to me (the one I failed to respond to) the first thing that came to mind were those little button/rivet anvils you use in leatherwork.

pi_17683.jpeg
 
That would work well Rick! If you want the ultimate, how about a sealed bearing pressed into a handle of some sort? heat would definitely not be a problem.
 
I have a friend who tried skate bearings. They are not made for side loading and didn't last long. A tapered bearing might work better.
 
Rick,

I thought of those too when I dreamed up the idea. They are steel - not too expensive - and may work better. The dish is really shallow - I don't think they would hold the spindle very well - or as well as a deeper dished piece.

TF
 
could you chill & press fit the metal bearing block?
make it .003-.005 larger than the hole, chill it down on a piece of dry ice, then tap it in place in the hole.
Once the insert is up to room temp, it's shouldn't fall out and when it's being used as a bearing block the heat will make it fit tighter.
not sure if aluminum would be the best material for this - maybe bronze would work better, since IIRC, it has better lubricity.

another alternative would be setting your bearing block in a stepped hole from the back side of the scale so you have a mechanical attachment.
 
What type of lube are you using? Even in a primitive setting, you can lube the joint with natural oils from your head (at the nasal labial fold and ear) These are naturally oily areas and provide plenty of friction reduction. So much so, that I've never burned through a thunderbird.

Are you using a cannon-bone drill adapter in conjunction with the hand piece?

I really can't believe that a lubricated hand piece is getting to 500+ degrees as I've held them through plenty of fires/coals. The mass of the thunderbird should be sufficient enough to absorb the heat being generated, like a heat sink, and the glue joint shouldn't be an issue.

Of course, this is just my opinion. What do I know?!?!
 
Did you just ask my what lube I use? That sir, is none of your business! ;)

In the case mentioned above, the aluminum was used dry. In the field, however, I tend to use a green leaf.



1066,

That is what I thinking as well - freeze it - .005 oversized - and press fit it in. I think that if I make it flush with the wood - it will not move. It isn't like it is getting horizontal pressure or being pushed out from the back. Every time it gets used it will be seating the aluminum piece. As long as it doesn't spin....

I will give it a good protoype test and I think I will know more.

TF
 
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