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Fibreglass laminated longbow - how to build

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jcs0001:
Now a bit on finishing/cutting the bow tips and nocks and bow finishing:

It is somewhat traditional (not everyone does this but I like to) to leave the tip at the top of the bow longer than the one on the bottom.  The reason is that the string is left on the bottom nock and when the bow is strung the string is slid up to and into place at the top nock.  If the tip is left long it makes it easier to slide the string up without pushing it past the end.

I always found that forming the nocks was difficult till I came up with a little simple jig.  I use a chainsaw round file to form the string nocks.



Shows the small angled block of wood with a chainsaw file in place.  A small spring clamp is sufficient to hold the block.  Always take your time with these and cut them gradually - a mistake at this point is difficult to fix.  Once they are cut sand them out to 400 or higher grit sandpaper - any sharp edges at all will eventually cut the string.



This is a bow I did a long time ago showing tip overlays.  The belly side has a clear glass overlay so it isn't very obvious.  The overlays on the back of the bow are white fibreglass and Kingwood.

Finishing the bow:

Once everything is done all parts are sanded off to at least 220 grit - more is better.  Gunstock oil finish (Birchwood Casey True oil is a good one) can be rubbed in several coats over the wood and fibreglass.  Don't use any kind of thick finish as it will tend to peel when the limbs bend.  Thin coats of lacquer spray finish are also good but I have never used it as I am not set up for spray painting.  I imagine similar spray bombs could also be used however.

John.

jcs0001:
A bit more about finishing:





Notice how the addition of some moisture brings out the wood grain and the wood grain under the clear glass.  Also notice the curve of the shelf.  This helps to reduce contact with the arrow and help to give better flight.  The shelf will eventually be covered with leather or something similar and may be built up a bit at the high point.



My friend had some snakeskins and decided to apply them to the back of this bow.  That is the main reason the bow has black glass on the back.  I've never done this but it does involve stretching the damp skin on the back of the bow and glueing with white carpenter's glue or something similar.

I will have to find some photos of the finished bow - it turned out very very well and my friend is very happy with it - with both it's appearance and it's performance.

There are lots of aspects I have covered quickly in this narrative and other than photos of the finished bow I won't go into it further.  If anyone has questions I will try to answer them and elaborate a bit if need be.

Thanks for looking,

John.

Bernd:
This was a very interesting thread. Learned a bit about making a bow.

Lot's of craftsmanship in something like that.  :thumbup:

Thanks posting it.

Bernd

jcs0001:
Thanks Bernd.

I've looked around and it appears I didn't take photos of the finished bow.  My friend is working out of town so next time I see him (may be weeks away), I'll get some and post them.  Hate to hold you in suspense. :palm:

John.

steamboatmodel:
Hi John,
Is the Fibreglass that you use the same as what is used for boat building?
Regards,
Gerald.

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