Relative Humidity

[SiongSA]

Hey guys,
I've got a queries about drying staves. I'm currently drying a bow that i made into bow dimensions while it was still green, so obviously its not gunna take very long to dry sufficiently but the thing is its summer atm in SA and the humidity is often up to 80% but on the other side of the scale in winter we have NO rain for 6 mouths, so how can i determine when to seal the bow because if its to humid its gunna take to much set and if its to dry its gunna be to brittle, so what should i do?

Sion,
South Africa

[Buckeye Guy]

Since your on the computer I think you must have some electricity available .
A hot box will help a lot so do a search on here for them as many have been posted in the past.
If you cant find or figure out how we can give you more info.

[straightarrow]

If you don't have a moisture meter you can wiegh the bow. When it stops losing wieght then its ready to go.  I have taken green wood roughed to dimensions then let dry for 6 weeks and its been fine.....only taking a 1/2" of set. I did do some heat treating though.

Jon

[SiongSA]

Since your on the computer I think you must have some electricity available .
A hot box will help a lot so do a search on here for them as many have been posted in the past.
If you cant find or figure out how we can give you more info.

i'm 15 so i don't think my parents will be pleased with a 7 foot hot box in the house lol, any more primitive ways to combat it?

[Pat B]

A lot depends on the wood used and it's hygroscopic rate(taking on and releasing moisture). Here in the US woods like osage or ipe have a slower rate or are not effected by moisture changes as much as other woods like hickory. Hickory releases moisture very slowly. It preforms best at about 6% m/c and gets sluggish at 9% to 11%m/c. Most other woods will blow up if dried to 6% but preform well at 9% to11%.
  If you have a/c in your home the r/h inside can and does stay pretty stable at a comfortable level. Storing your bow wood inside will help you maintain proper m/c for the wood used. Even with a finish on your bow there will still be a transpiration rate in your bow wood but the finish will slow doiwn that transpiration rate. Try to add your finish during a dry season or if you can tell what the m/c in the wood is, at a low m/c.
  I usually go by feel and sound as to the dryness of my bow wood. If it sounds crisp when you are working the wood then the wood is probably dry enough. If it has a ring to it when tapped on the floor it is probably dry enough. If, on the other hand a bow is sluggish or the tools have a dull sound when working it it is probably too much moisture.

[Parnell]

Hello,

What kind of wood are you working with?  I live in a similar climate, it sounds - South Florida.  So we have wet and dry seasons.  Is the bow in an air conditioned house while drying out?  
Do you have a heat gun?  You may also use other methods of toasting the belly of the bow, but this may be a very helpful thing to consider.
I'd take straigharrow's advice into strong consideration.  You'll be good to go, most likely.
Sealing the bow?  If it's been tillered right and shot in a bit, seal her up.  Different woods to better/worse in different humidity levels.

Let us know.

Good luck,

Parnell

[SiongSA]

If you don't have a moisture meter you can wiegh the bow. When it stops losing wieght then its ready to go.  I have taken green wood roughed to dimensions then let dry for 6 weeks and its been fine.....only taking a 1/2" of set. I did do some heat treating though.

Jon

dude i'm a bit confused about heat-treating i always assumed it was wood hardened but i assume i'm wrong?

Pat, i'm using ash for this bow

[Pat B]

You should be fine if you have air conditioning in your home. Ash is effected by moisture but is not as susceptible as hickory.
  Heat treating does harden the wood but in doing so it increases the compression strength so your bow is less likely to take on(as much) set...unless it has excessive moisture.
  An automobile that sits in the sun most of the day will work as a hot box.
  Lots of these things we talk about with building bows are general rules of thumb, basic rules. Once you have built a few bows and get familiar with the different properties of different woods, you will find things that work for you or don't work. A lot of it is experimentation we all do over the years as we build our bows. You will have to get comfortable with your knowledge of wood characteristics and building methods then things will come naturally to you without having to think about it. Until then, keep asking questions!

[SiongSA]

You should be fine if you have air conditioning in your home. Ash is effected by moisture but is not as susceptible as hickory.
  Heat treating does harden the wood but in doing so it increases the compression strength so your bow is less likely to take on(as much) set...unless it has excessive moisture.
  An automobile that sits in the sun most of the day will work as a hot box.
  Lots of these things we talk about with building bows are general rules of thumb, basic rules. Once you have built a few bows and get familiar with the different properties of different woods, you will find things that work for you or don't work. A lot of it is experimentation we all do over the years as we build our bows. You will have to get comfortable with your knowledge of wood characteristics and building methods then things will come naturally to you without having to think about it. Until then, keep asking questions!

My only source of heat-treating are my electric hot plates, for how long and how far away from the stove should the bow be? not sure how hot the plates get lol must check that

[Pat B]

I think a hot plate is what Marc St Louis started with. I don't know how long. I've never tryed that method.
  If you are basically a beginner, forget the belly toasting and just make a bow. You can jump off that bridge when you get more familiar with the bow building process.  I know at 15 it is hard to have patience(believe it or not I still remember being 15...never again!  ) but that is the best tool you can use when building wood bows. You have to learn to crawl before you learn to walk. 

[SiongSA]

I think a hot plate is what Marc St Louis started with. I don't know how long. I've never tryed that method.
  If you are basically a beginner, forget the belly toasting and just make a bow. You can jump off that bridge when you get more familiar with the bow building process.  I know at 15 it is hard to have patience(believe it or not I still remember being 15...never again!  ) but that is the best tool you can use when building wood bows. You have to learn to crawl before you learn to walk. 

i don't think patience is my problem, my favorite pastime is fishing lol but i don't want to make any major mistakea and try make a bow s good as i can:)