Red Oak Bow Questions

[mmattockx]

New guy here. First bow build of any sort. I have 3 decent red oak boards that I want to cut into laminations and glue up into an R/D bow. I have nothing against the flat bows, I just like the look of the R/D design better and I have the woodworking tools to do the cutting, thicknessing and form making. I am a new archer (have shot before, but not for many years) and have a target draw weight of 30# @ 28". Length will be 70" NTN with a glued on stiff riser that is 13" long to the ends of the fades.

Questions:

1) Given that I only want 30# draw weight I will not need anything near the usual 3/4" thickness that people start with on a flat bow. Does anyone have a rough idea what thickness I should expect to end up at so I can get into the correct ballpark with my glue up? A related question is how much material do people remove while tillering? I realize that is like asking how long a string is, but I want to be sure to leave enough material in the belly lam to not break through the glue joint while tillering. From what I have read and watched on the interwebs, there is a lot of scraping to find the final product and even taking 0.001"-0.002" or so at a stroke with a scraper adds up to a significant amount over many strokes.

2) All of the lam bows I have seen have the lams running full length and the riser glued onto the belly over the lams. Does no one run the belly lams up onto the fades similar to how it is done with fiberglass laminated bows? If not, why not? It would help with keeping the riser from popping loose and spread the bending forces into the riser much better than depending solely on the riser to belly glue joint.


Many thanks,
Mark

[aznboi3644]

If this is your first bow build of any sort I would just focus on making a simple bend through the handle long bow with emphasis on good tiller and not a broken bow.

Being your first bow build of any sort and jumping into a reflex deflex laminate is a pretty big step without ever even tillering a stick to bend without breaking.

[SLIMBOB]

Agreed. You have added several layers of complexity to an already formidable task. Getting a straight self bow right is hard enough in the beginning. If you have an experienced buddy helping...go for it. If not...go for it. Just be prepared for a tough slog.

[mmattockx]

Agreed. You have added several layers of complexity to an already formidable task. Getting a straight self bow right is hard enough in the beginning. If you have an experienced buddy helping...go for it. If not...go for it. Just be prepared for a tough slog.

I'm OK with a tough slog. However it works out I will learn a bunch and the cost of a couple oak boards isn't prohibitive if it ends up broken.

I guess I will just have to go ahead with it and see how it goes if no one has any info on the starting thickness for lighter limbs or running the belly lam up onto the fade. It won't all happen until spring, but I will post pics when there is something to see.

OT - what's with the insane verification routine just to post anything? Does that go away after a minimum number of posts or something?


Thanks,
Mark

[aznboi3644]

Starting thickness is just keep shaving wood until it bends.  It’s called floor tillering. 

[artcher1]

I'm not in the "floor tillering" group so I'll throw some numbers your way. My method is "taper tillering", where you apply a taper, which produces your tiller. To me, floor tillering is nothing more then to check to see if the bow is light enough to string. Once you get your string on, you adjust your tiller from there. Build your first bow, and then adjust measurements for your next bow if needed.

Ok, start with a limb width of 1 1/2" to mid-limb, then taper to 1/2" tips. Then for limb thickness, 1/2" at the handle fades to 7/16" to mid-limb, and then reverse taper back up to 1/2" at the tips (tips can be reduced later).

Those numbers will only get you started. Like I said earlier, you'll have to build a bow or two of this design to really get a good handle on taper tillering.

Post pictures as you go, there's lots of good bowyers here who will help you with your build...……..Art

[bjrogg]

I’m sorry I cannot help. I’ve never done a lam bow before. I tend to agree with a simple design for your first. However I wish you good luck on your path.
Bjrogg
PS it does seem like 30 lbs @ 28” and a 70” ntn should be quite doable

[PatM]

Wood tends to not lend itself to that style of construction.  It can and has been done but requires more work than it would if it used glass instead.  People tend to struggle getting the laminations to fit the curve of the fade.

[Hawkdancer]

The verification does go away - I think it is a test of your patience and an initiation to bow making . Seriously, it helps keep spammers out, I think.  Welcome to PA!  Good luck with the oak, you might look at Paul Comstock's "The Bent Stick" for info on a starter bow.  Also ask questions here, these folks have a wealth of experience.
Hawkdancer

[mmattockx]

Starting thickness is just keep shaving wood until it bends.

I do get that, I'm just trying to get into the approximately correct neighbourhood to start with instead of beginning with an uneducated WAG.

Build your first bow, and then adjust measurements for your next bow if needed.

Yeah, it is an empirical thing in the end. I was just hoping to learn from someone else's experience instead of reinventing the wheel on my own.

Ok, start with a limb width of 1 1/2" to mid-limb, then taper to 1/2" tips. Then for limb thickness, 1/2" at the handle fades to 7/16" to mid-limb, and then reverse taper back up to 1/2" at the tips (tips can be reduced later).

That is a big help, thanks.

PS it does seem like 30 lbs @ 28” and a 70” ntn should be quite doable

I've seen a number of red oak bows online that were well up into the 40lb range, so I figure I should be OK if I don't screw anything up.

Wood tends to not lend itself to that style of construction.  It can and has been done but requires more work than it would if it used glass instead.  People tend to struggle getting the laminations to fit the curve of the fade.

I expected that would be a problem and plan to steam bend the lams to fit before the glue up is done.

The verification does go away - I think it is a test of your patience and an initiation to bow making . Seriously, it helps keep spammers out, I think.  Welcome to PA!  Good luck with the oak, you might look at Paul Comstock's "The Bent Stick" for info on a starter bow.  Also ask questions here, these folks have a wealth of experience.
Hawkdancer

I understand it is anti-spam, it is just more extreme than any I have seen. Thanks for the book recommendation, I will go look for it before I really get into the building portion.


Thanks for all the help,
Mark

[bradsmith2010]

After the first one,,,u can make adjustments if needed,..make the lams thinner than u think,..cut the bow shorter if u miss the weight...
U can side tiller to keep from going through belly lam..

[mmattockx]

After the first one,,,u can make adjustments if needed,..make the lams thinner than u think,..cut the bow shorter if u miss the weight...
U can side tiller to keep from going through belly lam..

Now there's some of the great advice I had been hoping for, sweet. Rookie me never thought about cutting it shorter if I get too light.

I was thinking 0.100" to 0.150" for the various lams. 0.150" was for the belly lams to give a bit more leeway on tillering and 0.100" for the back lam with the other two being 0.125".

I forgot to mention that I plan to back the bow with some linen as insurance and will be gluing with Titebond III.


Mark