Hot box info please

[Don Case]

   I think I'm going to build a hot box. I don't think my Ocean Spray is drying enough. The RH seems to hover around the 60-70% here and the bows seem to want to take a little set.
   Would you guys give me a few pointers as to size (I won't be making a lot of bows), temperature needed, how to use it, construction and just anything you can think of that might be of help.
Thanks
Don

[Don Case]

I did a Google search and found out most of what I need to know except, how do you know how long to leave the bow in the hot box? Right now according to the chart my bow has a MC of 12-13%. It has reached equilibrium and this is pretty typical weather here for the foreseeable future. I would like to get it down to 9-10%. At this moment the bow is in the car where the temp is 100 degrees and the RH is 10%. This would be a MC(if left to equilibrium) of 2.3%. A bit TOO dry. How do you know when to stop?

[bow101]

The car works I guess, better to be outside.
 I would find the hottest spot outside the house with at least 6-8 hours of full sun. As long as the staves (saplings) are sealed they should be good to go in a week or so. Probably get 'er down to 7-8% I have done this for the last couple years works like a charm, the sun is free.
All I do is cut a sliver off one end and roll the sawdust between my fingers,  if it does not stick together you should be good to go.  I use to work in a semi damp wood shop and all the wood was kiln dried, after sitting in the shop it was around 9-11% or higher depending on time of year.  So I had a lot of practice with wood.  Must of worked over 50,000 board feet, mostly douglas fir, poplar, oak, alder, hemlock and some cedar.

[mikekeswick]

Google temp/relative humidity chart for m.c. in wood. Bingo moisture content!

[wizardgoat]

Any stave I think still had moisture in it, I weigh it keep a close eye. I bought a kitchen scale, and to me, this is the most accurate.
Every couple days I weigh it, and eventually it stops losing weight.

[Don Case]

Mike and Wiz. Correct me if I'm wrong. I have a good scale and the stave had reached equilibrium (same weight for a month) so I checked the chart and it says I have 12-13% MC. Everything I've read says this is too high. If I could find a spot that was 50% RH and 70 F eventually the stave/bow would get down to 9% but it would take weeks. In the car/hotbox the temp is 100 and the RH is 15%. That would be way too dry. I have to stop somewhere. That's what I can't figure out.
  Wiz, you're in Vancouver and I'm on the Island so our temp/RH must be similar. So when the stave stops losing weight you fly at it and don't concern yourself with MC?

[wizardgoat]

Ya, you still working lots of ocean spray? It's a very dense wood, and doesn't dry as quick as other white woods. If you leave it in your car with this weather, you will run the risk of getting to dry. Bring it into the house after a while where MC doesn't fluctuate as much.
I've had a stave that got to dry, and it actually started to gain a little weight when I brought it in.  Whenever it stabilizes for a week or so, your generally good. My dry wood stash is getting big, so I'm not in as much of a hurry to get into wet stuff any more.
I don't concern myself with MC charts and RH. Just weigh it everyday and you can literally see it get dryer and dryer, it starts losing weight very slowly, then finally it'll equalize

[Don Case]

Maybe I'm overthinking, I have a tendency to do that. I us OS because there is lots of it within 10 minutes walking distance from my house. It is a bear to dry. With the bow I'm working on now I could see the weight change with the RH so I figured it was dry. I just get a little choked when I de-string it and see that bit of set.

[FRITZ 86]

Don I have no experience with ocean spray, but the same concerns as yours for hickory as I live in Louisiana. I built a hot box and have dried some staves in it, but found that it does just as well under my bed in my central ac house. I did buy me a humidity meter to keep with the wood under my bed and it stays around 50% in my house.