Primitive Archer

Main Discussion Area => Bows => Topic started by: sleek on September 28, 2018, 02:00:31 pm

Title: Bamboo backing strips expectations
Post by: sleek on September 28, 2018, 02:00:31 pm
When you buy them,  how thick, wide, long do you expect them/need them? Is it ok for edges to be sharp or do they need to be cut square? Also, how long do they need to be cured for?
Title: Re: Bamboo backing strips expectations
Post by: tattoo dave on September 28, 2018, 02:14:52 pm
Not sure on the thickness, obviously that will vary through the piece of bamboo, from the center to the sides. Just make sure it's evenly sanded. The width is typically 2". The length is usually the standard 72" backing. Most of the time they are squared edges, but if they are sanded flat on what would have been the inside of the trunk, the sides may be pretty thin. I have no idea what the time duration is for curing.

Are you buying some, or making some?

Tattoo Dave.
Title: Re: Bamboo backing strips expectations
Post by: Bayou Ben on September 28, 2018, 02:36:32 pm
Most of the stuff I've seen that people sell in slat form is Moso variety and is usually 2" wide, 6' long.  It's made from large diameter bamboo and you can normally get more width out of it because there's less of a crown. 
I've recently started to get whole poles in the Madake variety.  These seem to be stiffer and tougher but the diameter is much smaller, so you are limited by how wide you can make them.  About 1.5" is max width on this bamboo. 
I always have to grind them down to about .125" so the thickness isn't something I'm concerned about.  Sharp or square edges wouldn't make a difference as long as the piece is wide enough for your needs. I normally grind mine down to almost a knife edge on the sides, maybe 1/32" thick. 
I buy them already dried, but they do dry quicker than wood since they are so thin.  I would imagine a couple months to fully dry or a couple weeks if you had a drying box.

Title: Re: Bamboo backing strips expectations
Post by: Pat B on September 28, 2018, 03:03:04 pm
The boo for a boo backed bow when prepped as a backing strip will be about 1 3/8" to 1 1/2" wide, 1/8" at the crown at the handle and it can have a razor edge. Generally when you buy a boo backing strip it comes at about 2" to 3" wide and as thick as the boo is naturally. From this point you remove the thickness so you have a flat belly side. Then you draw out the bow shape, cut it out and thin to the above dimensions.
Title: Re: Bamboo backing strips expectations
Post by: Del the cat on September 29, 2018, 01:18:17 am
It comes full thickness, you have to plane it down, which is fairly easy if you sharpen the plane blade first :)
Del
Title: Re: Bamboo backing strips expectations
Post by: Badger on September 29, 2018, 09:19:08 am
Lately I have been doing more by hand just so I can get in the exercise. I use the draw knife to take it down close to a knife edge and then use my belt sander to flatten it. Moisture content on the backing strip is not real critical as long as it is pretty dry say less than about 12%.