oak core limbs?

[nicko88]

so im new to bow building but have been working as a carpenter for 8 years so am not new to timber.

i have done a fair amount of research but seem to read all of the same advice. 90% of people use the same tried and tested materials.

so. oak core limbs. do they work?

i have some 2.5mm strips of oak which are 50mm wide (2") and was wondering if they are suitable or would even work as the core of some recurve limbs (they were free).

i would use triaxial fibreglass with longitudinal as well as 45degree fibres making an x making up the 3 directions of fibre for the back and belly of the bow.

is this likely to work or end in tears?

i have already built the riser and am currently also making pvc limbs to mount on it.

nick

[snapper1d]

I have use oak lams and they have and still are working fine!

[aus-archer]

I've used red and white oak for core lamination between raw bamboo no worries. Also found they take less string follow then using action boo as a core with raw bamboo back and belly.

[LittleBen]

Oak is suitable. But the question is really how accurately they're cut. Obviously they end to be as accurately cut as possible for use in a glass bow limb.

[JamesV]

Almost any core wood will build a descent glass bow if the moisture contend and grain are good. Cypress makes a smooth shooting bow, edge grain pine makes a good shooting bow but shouldn't be cured in the hotbox. Even nanner popsicle sticks will make a good shooting bow.

Think outside the box and have some fun.

James

[KenH]

Wood only supplies 12% to the total wood-glass bow equation; the glass provides 88%.  Nearly any wood besides balsa, and maybe aspen, is suitable.  As mentioned, the lams need to be accurately made in thickness, not just ripped on a tablesaw.

[nicko88]

beautiful. this is what i was after. a few guys at the club told me this would explode in my face which is why i decided i would try here.

it is a pretty accurate cut to tell the truth. i was installing laminate flooring at work and these are offcuts.

the top layer of laminate is cut exceptionally accurately to depth. the width and length will match my bow limb design. the only tolerance whatsoever will be my sanding off the laminate / glue from one side. this shouldnt be too hard to get reasonably accurate. afterall this is a project bow and first attempt, not a record breaker.

the wood grain is also what i would rate as excellent. no knots and a very straight longitudinal grain direction.

to rack brains while im at it. is triaxial fibreglass good for bow building or is there a better alternative with great speed and stability?

[Pheonixarcher]

I've never heard of triaxial fiberglass, so I won't comment on that, but Gordon's composites is the most widely used fiberglass in bow making.
Show us some pics of this glass, and those lams please. We love pics around here. Lol

[Beanbag]

Just a question about oak, I thought white and red oak were pretty close to Ash and Elm for lams?? Have some to work with and was wondering also thks Jim G

[nicko88]

http://s1372.photobucket.com/user/njweekes/media/Mobile%20Uploads/IMG_20140909_173528_zps9zlpbs46.jpg.html?o=0

 http://s1372.photobucket.com/user/njweekes/media/Mobile%20Uploads/IMG_20140909_173539_zpsznpfvlcs.jpg.html?o=1

 http://s1372.photobucket.com/user/njweekes/media/Mobile%20Uploads/IMG_20140909_173617_zps5y6loatc.jpg.html?o=2

alrighty theres some pics. 2 of laminates ive already removed, and 1 still on the board.

theres the triaxial fibreglass but it looks a little different to how to photo picked it up. if the detail is enough though you should see 2 sets of fibres running in an X and 1 running length ways.

[Beanbag]

That glass looks like the stuff used in boat building. Just got done redoing a transom lay-up for a friend with that glass. I don't think it will work very well in a limb. As a kid I tried making a crossbow with e-glass and poly resin. Did not take long to splinter. If you laid up a piece with epoxy on a good flat with the grain perfectly straight you might find out if it has the flexibility to work. I think not though. Good luck

[nicko88]

most of the "archery" glass ive found seems to be all pre-finished.
the carbon weave on my border bow looks to be in an X pattern, which was where i got the idea from. i guess now ive got it ill try one and see how it goes. if it sucks, which glass lay ups do you recommend?

[KenH]

Yeah... what you're picture shows is what I call "boatbuilding glass"  (I live on a fiberglass bat).  By the time you put enough coats of epoxy on to make it smooth, the bow is gonna weigh a ton.  Back in the bad old days some makers did use woven glass like that I understand.  But modern "archery glass" has unidirectional fibers which are more important for the stresses we put on bows.

I did see a YouTube of a kid in Indonesia who made a pair of fiberglass limbs for a 3-piece takedown bow by laminating three or 4 layers of glass cloth with brushed on layers of epoxy.

My advice?  Bite the bullet and by "archery glass".  Black is the least expensive for prototyping bows.  

Carbon weave is a "whole 'nother kettle of fish".  Not for the faint of heart.

[jsweka]

Originally posted by KenH:


My advice?  Bite the bullet and by "archery glass".  Black is the least expensive for prototyping bows.  

 

Exactly!  For $30.00 you can have the same glass as the professionals.  Although it is sometimes fun to  attempt to reinvent the wheel, more often than not you just end up with a bumpy ride.