another "cutting backing" question...

[DC]

I did a little surfing and it looks like for anything but epoxy an unsanded surface is best. But then I only surfed for ten minutes

[Marc St Louis]

I'm planning on quarter sawing maple strips myself. I've got a ton of it. Sounds like that's the way to go. Does it make sense to cut them at about 1/4" thick and finish em off on the jointer?

I'd like to try splicing billets and backing them with the maple, like Marc does.

The only time I have cut a backing 1/4" thick was for a 100+ lb bow.  I generally cut my backings no more than 3/16" thick and then thin them on my jointer.  I also progressively thin them so that they are thinner towards the tips and I always sand both surfaces before gluing

[upstatenybowyer]

I'm planning on quarter sawing maple strips myself. I've got a ton of it. Sounds like that's the way to go. Does it make sense to cut them at about 1/4" thick and finish em off on the jointer?

I'd like to try splicing billets and backing them with the maple, like Marc does.

The only time I have cut a backing 1/4" thick was for a 100+ lb bow.  I generally cut my backings no more than 3/16" thick and then thin them on my jointer.  I also progressively thin them so that they are thinner towards the tips and I always sand both surfaces before gluing

Thanks Marc. This helps a lot. 

And thanks to all, I'm learning a ton on this one and on DC's as well.

[hoosierf]

I build a sort of quickie laminate bow with a quarter sawn red oak back and a white ash belllly. I’ve done it with the white ash belly quarter sawn and riff sawn. The quarter sawn versions have better cast and are less prone to chrysal. I make them narrow and long (7/8” wide x 72” long) with a deep handle and keep them under 45lbs. They take a little set but not too bad and they are sweet smooth shooters. So my experience with ash would suggest to me that quarter sawn is better for belly wood.  I once broke a riff sawn red oak back in tension with a lemonwood belly so i think quarter for the back is the way to go with tension strong woods.

[Morgan]

I would like to cut my own backings from 3’ sections of a tree say 5” in diameter at the small end. What would be the best way to break down the log to get quarter and rift sawn slats with no runoff? My mind keeps going on this direction.... Use stove a pipe straight log. Rip a line parallel to outside of the log from pith on small end to the butt end which would leave pith plus some. Then rip strips from that with the just sawn surface on table and crown up. That would yiel a combo of rift and quarter cuts, but would make a lot of waste I think. If any of y’all have a good breakdown method, I’d love to hear it.

[willie]

What would be the best way to break down the log to get....slats with no runoff?

do you wish to also eliminate the possibility of having spiral run-off in the board?
what species of log is it, BTW?

[Morgan]

Yes,  I would like to have no runoff of grain. Wood will be hickory, elm, or hackberry. Those are what I have most readily available. I guess white oak is on the table too, but the deer sure like their acorns so I’d just as soon leave them be.

[willie]

if I wanted to also eliminate spiral grain, I would choose a log that has been split and shows no propeller twist.
spiral run out cannot be seen in a milled board, as with the wavy trunk/quartersawn thing mentioned earlier
not all woods split as easy as others though. perhaps someone that has spit those species that you mentioned can advise on selection. spiral grain can sometimes be seen in the bark, so a bit of eyeball practice might pay off so that you don't cut down trees needlessly, that said sometimes even a tree that does not show it in the bark, may well have prop twist.

once you have a twist free 1/2 or 1/4 log, you might have to glue a tapered ripping here or there so it lays flat on the saw table

what tool will you be trying to use to mill the log?

[Morgan]

Willie, the trees won’t be cut for backing, what I will use would be off cuts from stave logs or branch wood from the bigger trees. I had a hackberry stave that I intended to cut into backings because it split dead straight, but it’s a couple bows now lol. I will be using a delta 14” bandsaw. I used to own a Lucas swingblade sawmill. I wish I had that thing now. You could set it up to run parallel to the taper of the log and could quartersaw with it easier than any other mill.

[vinemaplebows]

Flat sawn is fine for an appropriate specie, but you have to be at least as picky about the grain as you would with a board stave.  Straight ring lines all the way down the face.

Quarter-sawn is definitely the best.  The only problem is that if it came from a wiggly log, it can hide front to back run-out because the nice straight grain lines look so nice.  That's pretty rare, but I've seen it.

Yep, has got me a time or two. Most of the time there is a slight chatter in the wood if you are planing, a drum sander can get you because everything is so smooth.

[DC]

Yep, has got me a time or two. Most of the time there is a slight chatter in the wood if you are planing, a drum sander can get you because everything is so smooth.

I was wondering if a hand plane would show it. If the grain is running out it should be smooth one way and ragged the other. If it planes the same both ways it should be good. Does that sound right?

[upstatenybowyer]

How about a backing made from the center slice of a pipe-straight sapling? Say, 2" in diameter? Technically that would be half sawn right?

[PatM]

Saplings tend to have grown over knots.

[willie]

I wish I had that thing now. You could set it up to run parallel to the taper of the log and could quartersaw with it easier than any other mill.

[Springbuck]

Saplings tend to have grown over knots.

Exactly.  I take backings from the OUTSIDE of small elms occasionally, but the middle of small trees are full of the things left from when the tree was even smaller; knots, grain wiggles, branch roots, etc.  I usually just get a couple out of a 2-3" tree, but if it was perfect, you might get 4 out of a 5" trunk, 1-1/2" wide or so.  I wouldn't bother with the middle, though.

Small elms or ashes growing in shady thickets often have that almost perfect 3 inch x 3 foot section that is smooth and clean, but underneath it, who knows?  The trick is to work them while green.  I chainsaw them in half, thin them to about 1/4", then clamp them to a straight board to dry.  Leave NO sunlight showing between backing and board, and clamp it snug and straight lengthwise.  Then, when it's dry, you can mill the gluing surface better.  The sides may wander a bit, but get the thickest part of the crown straight down the middle.

Two issues:  When you clamp it, you have to make sure the crown doesn't end up wandering side to side.  AND, you have to make sure it is really dry.  If you glue up a backing even slightly green to a belly, it will continue to dry into un-manageble reflex.  Trust me, that blank is still sitting in the corner of my garage.