#3 - Maple Pyramid Bow

[mmattockx]

It has occurred to me I never posted this here. This is my third bow, from a maple board. 65" NTN, 38# @ 28". The dark wood is mystery wood from a bin of off cuts. Could be white oak, but that is only a guess.
















Mark

[Longcruise]

That's a nice looking bow.  Did you back it?

Ive done a couple maple boards but couldn't find any truly safe boards so I backed with rawhide.   

I wanna come to your house and Sneak in and tear that weatherrest off. 

[mmattockx]

That's a nice looking bow.  Did you back it?

Thanks. It had quite a saga and it is likely a miracle it became a bow at all. There was a pin knot on the back that concerned me, so I initially backed it with cotton fabric and TBIII. The rest of the board was nice, straight grain and I wouldn't have backed it except for that knot.

Got it worked in some on the tree and then decided to heat treat the belly and put a touch of reflex into it. During heat treating I scorched the edges of the backing a bit in a couple spots. I didn't trust it after that, so I sanded it off (sanding all that off by hand was certainly penance for being a muppet with the heat gun...) and put a small patch of vectran fibres over the pin knot and left the rest of it unbacked. It was OK after that and I finished tillering it out to 28". First crisis averted...

Similar to Roy's recent BBO build along, a knot had appeared on the belly side of the lower limb when I was removing wood at the beginning. It was small and didn't transfer through to the back, so I soaked it with CA and carried on. After a few hundred shots that spot started hinging. So I rasped off some of the belly wood at the hinge and glued a patch over the knot area. I didn't pull it back perfectly flat when I glued the patch on and you can still see where the hinge was on the limb, but the patch has held for 1000+ shots now and nothing has moved, so it is hopefully going to stay that way.

I wanna come to your house and Sneak in and tear that weatherrest off. 

Is that the tin siding? This is an old grainery that was converted to a shed somewhere long before we got to the place and I know nothing about it.


Mark

[Flem]

Nice looking bow and you got those limbs working real nice
Little bit of set it looks like, unless you built it on a string follow form?
I like a little string follow, makes them more forgiving. I bet that bow is fun to shoot.

[Buemaker]

Looking good.

[Longcruise]

  Is that the tin siding? This is an old grainery that was converted to a shed somewhere long before we got to the place and I know nothing about it. 

Was referring to the arrow rest. 

[mmattockx]

Nice looking bow and you got those limbs working real nice

Thanks. I designed the bow using David Dewey's spreadsheet calculator and cut it to near final dimensions, then drew it out a bit on the tree and checked the weight, then fine tuned to final dimensions. Only had to do a tiny bit of tillering adjustment on one limb to get it to where it you see it now. I'm going to leave the tips a bit stiffer on the next one and maybe let it bend a bit more out of the fades, but I'm happy with it for only my third attempt.

Little bit of set it looks like, unless you built it on a string follow form?
I like a little string follow, makes them more forgiving. I bet that bow is fun to shoot.

It has a bit of set and takes something like 1/2"-3/4" more immediately after unstringing (It's been a while since I measured). It is really hard to avoid all set on a wood bow, there always seems to be a little bit in there somewhere.

Was referring to the arrow rest. 

Ah, I missed that completely. All my arrows have vanes, so I shoot off a rest. If I ever break down and buy some with feathers then I can start shooting off a shelf.


Mark

[Mad Max]

Looks really good

[onetone]

Nice bow! Well done.

[Roy from Pa]

Very nice...

[williwaw]

Quote from: Flem on January 09, 2021, 02:17:13 PM

    Little bit of set it looks like, unless you built it on a string follow form?
    I like a little string follow, makes them more forgiving. I bet that bow is fun to shoot.

It has a bit of set and takes something like 1/2"-3/4" more immediately after unstringing (It's been a while since I measured). It is really hard to avoid all set on a wood bow, there always seems to be a little bit in there somewhere.

the set looks like it happened in the right places. Did the spreadsheet do a fair job of predicting where the set causing strain occurred?

If I ever break down and buy some with feathers

I think you will wished you had earlier, when you do.

[mmattockx]

the set looks like it happened in the right places. Did the spreadsheet do a fair job of predicting where the set causing strain occurred?

I don't know that I ever compared the two closely for set. The design was intended to have very even strain for the whole length of the working limb and the top limb shows set evenly distributed along the full length, almost in textbook fashion. The bottom limb is similar but has a small kink remaining from where I fixed the hinge.

I think you will wished you had earlier, when you do.

Very possibly. I haven't avoided them intentionally, it is just how things worked out so far.


Mark