Sneak peak.

[Bob Barnes]

I've used black walnut heartwood but it seems to be brittle to me.  I like thin osage lams on an osage bow. 

[Selfbowman]

Ok

[bjrogg]

Will black walnut be strong enough? I have some bow limb laminates about 3/32” thick . And I think I will get some slower setting  glue.

I have never used B W by itself. Not sure about that.

I think the combination on this one was Osage bow that was about 1/4” thicker in handle than limb. Much like yours looks. If you can have that little bit of thickness it really helps.

Then I think it was black walnut- oak- black walnut and finally a sliver of juniper

I have never had a problem with any of them but it does make filling and sanding a little challenging because of the different wood densities

Bjrogg

[PEARL DRUMS]

Use EA40 and don't tooth it before glue up. I know you read and hear about toothing all pieces with EA40. But, glass bowyers prefer EA40 over any other epoxy and I'm quite certain no components are toothed on a glass bow I never waste time toothing and I have had zero delams of any sort with EA40.

[Selfbowman]

Thanks pearl I know you do them all the time. Is that like  smooth on?

[Bob Barnes]

EA40 is smooth-on

[Selfbowman]

Ok but I have had pop offs with it too. Maybe I need to go to a glue up class.🤠

[superdav95]

On my cans of smooth on ea40 it says mixing 2 parts a to 1 part B will yield higher strength results and resistance to heat.  If you prep and score the surfaces well and wipe clean with acetone it will hold.  If you’ve got a heat box at your disposal then even better.  Bake it for 6-8 hours at 150 degrees while keeping it clamped.  Best of luck. 

[paulsemp]

I would use the smooth on as recommended. I would also laminate a piece or two in between your handle or build it up with multiple laminations. I've had failures in the past where the glue lines weren't very good and I figured smooth out would make it up. It is good at making stuff up but I always use too much clamp pressure trying to get it to come together and I feel like I squeezed way too much epoxy out of the joint. I think it's easier to make multiple laminations come together without excessive clamp pressure then one block to another unless they are perfectly machined flat. I've done some abrupt transitions like that and always had better luck with multiple laminations. You are putting the stress multiple glue joints instead of just one. I also only weigh out smooth on instead of trying to do a  part to part.  I only use the one-to-one ratio, got sick of having extra of one part. Just my two cents though

[Selfbowman]

Thanks guys will do.

[George Tsoukalas]

Smooth, rough or toothed? It s always a good idea to read the directions on the glue. Jawge

[mmattockx]

The thin laminate strips will bend slightly if they have to and not pop off. You can use a couple of different wood types to make it more interesting. I’ve had really good results using this method and never had one pop off

Not picking on you, BJ, as this is a common belief. There is no way that the thin lams can bend once glued into a block. As long as the glue is as stiff and strong as the wood (EA-40 certainly is) that laminated block will behave exactly the same under load as a solid block of wood of the same dimensions.

I think it's easier to make multiple laminations come together without excessive clamp pressure then one block to another unless they are perfectly machined flat.

I suspect this is the reason people have more success with laminated handles. It is definitely easier to get good glue lines with thinner laminations that can conform to the other side of the joint. Laminated handles also look great when contrasting woods are used.

Smooth, rough or toothed? It s always a good idea to read the directions on the glue. Jawge

Smooth On's technical info says to prep lams by planing or sanding with 120 grit sandpaper, which I don't think anyone does. I use 50-60 grit on my thickness sander just because 120 would go far too slowly and would clog and wear out continuously. It might be worth block sanding the lams with 120 grit after the thickness sander but I haven't tried that yet.

Here is a link to the EA-40 Technical bulletin that specifies 120 grit for prep: http://www.smooth-on.com/tb/files/EA40.pdf

On page 2 of the bulletin it has specific bow making instructions. It says to plane or lightly sand the lams with 120 grit paper.


Mark

[Selfbowman]

Her are some pics of the handle before the glued on piece.

[Selfbowman]

Close to enough wood for the handle not to bend I think?

[Selfbowman]

Pic