Primitive Archer
Main Discussion Area => Bows => Topic started by: wizardgoat on March 08, 2014, 01:10:51 am
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White oak stave cut in the fall was showing 8%, hacked it down to floor tiller and it's showing 14% now. At what % should I still be worrying about checking, should I still seal the ends up?
Cheers
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If it is truly 14% then I would not bend it anymore until its down to under 10%. But then I don't measure moisture with a meter so I'm really just passing on info that I've read. I don't trust the moisture meters at all, at least not for bow making.
If its been sitting around in the same conditions for some time and it has not checked by now then it probably won't. If its been sitting around in moist conditions and you expect the air to dry up fairly fast then it might check then. All depends on humidity levels and such.
When you pick up a hunk of wood at room temperature you can kind of tell if its still a little moist because it will often be a little cool to the touch. If it feels dry and yet I'm still in doubt, I'll heat the wood carefully in a certain spot and watch carefully to see if I see any tiny checks forming. Depending on the wood and how thick it is I'll determine that it is dry enough. With oak I would drive the moisture out slowly by lowering humidity, either by moving the stave somewhere else or into a hot box, always keeping an eye on it initially. And where I would remove some woods from the hot box at such and such a time I would maybe double the time for oak.
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Thanks for the in depth answer. I'm still pretty new to making bows,
so I'll trust the moisture meter for now. Just doesn't seem like it reads
very deep into the wood... Cheers!
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Especially when you're new to bow making, you should not trust the moisture meter in bow making. It is such a tricky device that requires skill and know-how. Very, very few bowyers rely on this piece of equipment alone to make their decision whether a piece of wood is dry. It always measures the surface of the wood. So you need to measure freshly exposed surface to get a somewhat decent figure. But still.
It's better to weigh the wood accurately (to the gram at least) every now and then. If the stave has not lost any weight (equals water) for at least a week in a row, it will have reached EMC.
If the stave was cut in fall, it may have dried a bit, a lot or not at all. Depends on many factors that you didn't yet clarify. How big was the stave since fall? Where did you store it; outside, cellar, in a hot box? When was it reduced and to what dimensions? Was the stave sealed and/or did you leave the bark on? All these factors influence the drying speed of the wood.
A quick answer to your questions: the oak has probably at least 14% moisture left. Since it has been drying for at least four months, it has probably lost a substantial amount of moisture. It should be dry enough to not start splitting and checking now, but it is not dry enough to allow you to bend it. Reduce to near floor-tillered dimensions, and put to dry for at least another month indoors where EMC will be around 9%. Monitor moisture loss by weight loss.
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What kind of humidity has it been stored in the last 5-6 months? If its under 35% Id be working it. Whitewood dries very, very fast. Especially roughed to floor tiller first.
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I go by feel. Either by the way the wood feels under the tools or sounds under the tools(crisp) and by the resilience as you bend the wood. Does it feel mushy or spring back eagerly.
The problem I have with the pin type moisture meter is it only measures as deep as the pins go.
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Wizard, you did well.
Use the moisture meter to give you empirical evidence of moisture content.
Most meters only give surface readings.
To get around that use it through out the process.
Most woods do well at 8-10% except for hickory which likes 6-8%.
Rough the bow out and keep checking. When you get a reading above the gudelines stp and let it dry.
Continue to floor tillering and check. Stop as needed. Let it ry.
For those that don't have one, I use the mini ligno which is available from 3 Rivers and they are a sponsor.
Easy to use. No muss. No fuss.
:)
Jawge
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BTW I've used this process for years. Once I started using a meter my bows have taken less set.
Last year I finished a hickory bow that started at 0 reflex and ended at just over 1 inch of set.
Jawge
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When I need to buy something I buy from 3 Rivers and they are a sponsor.
http://www.3riversarchery.com/Mini-Lingo+Pin+Moisture+Meter_i5700_baseitem.html
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When I need to buy something I buy from 3 Rivers and they are a sponsor.
http://www.3riversarchery.com/Mini-Lingo+Pin+Moisture+Meter_i5700_baseitem.html
I found 3Rivers when I first started getting PA Magazine. I lucked onto them, and have stayed with them because of their quality service (I always seem to get Sean on the phone, great guy!).
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The mini-ligno is a great meter IMO. However, it does not read down into thicker wood with just the standard short pins. I have the slide hammer attachment with 2" pins so I can get accurate readings on thicker wood. I typically keep some scraps from the same tree, stave or lumber in the same thickness to drive the pins into so I don't damage my staves. Matt
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Thanks everyone. Ya that oak was cut in the fall and stored undercover outside
Up until last month where it was cut to stave size and I brought it inside. Ends sealed bark on. I live in Vancouver and its been cold and wet for a while.
I just wasn't fully sure if I had to be worried about checking with 14%, especially because its been outside, and I just brought it in.
I got paranoid and sealed it up last night, better safe than sorry I geuss!
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Whitefeather, perhaps my first post will help you get around that problem. Jawge
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Yeah Jawge that works well and I do that while working on my bows along with keeping rh readings where I'm working, but I have staves and gunstock blanks that end up all over creation and I like to know within reason that I'm sending something that will work and the long pins allow me to do that. For example, if I gift a stave to a new guy and his bow is having issues I can rule out moisture as the cause.