MOISTURE

[Drcal]

I want to turn a candle holder...the blank is a 3X3X4 Hormigo and has 25% moisture. Can I turn and completely finish it or that too much moisture?

Carmen

 

[PaulDoug]

I'm certainly no expert but my guess is that is too much moister. I think you want it less than 10%. Coarse some of it depends on the type of wood also. You could nuke it in the microwave to remove more moister or soak it in DNA.

 

[IPD_Mrs]

Talk to some of the bowl turners. Some of them do a rough turn while green, then let it set and dry before finish turning. I think you might want to take the blank and put it in a bucket full of saw dust. You would be surprised how soon it will be ready to turn.

 

[MesquiteMan]

What did you measure the moisture content with? Did you interpolate for the different wood specific gravity? If you just stuck a pin moisture meter in it without using any correction, then the reading is not accurate.

Also, it depends on the wood. I have never heard of that wood but then again, I am only an expert on Central Texas wood. If you were doing it out of mesquite, then it would not matter if it was 50% moisture content. However, if you were doing it out of Live Oak, then 20+% is way too much and it WILL crack.

 

[penhead]

I picked up a 2x2x12 piece of that "Hormingo" wood at Woodcraft and I didn't measure the MC of it, but I found out it was still pretty wet when I could see the moisture weeping out as i turned it....it cracked ;(

Hormingo is in the same family as Granadillo and can be used as a substitute for Granadillo or for some of the lower end rosewoods.

Pretty wood, but my suggestion would be to dry it out a little more first...of course, it may depend on the diameter of what you are turning...and if the turning/sanding process may be enough to dry it out..!

 

[nativewooder]

Our year-round average humidity seems to be about 13% which is where you would want the moisture level. However, since we are going to have an arctic front rolling through, the relative humidity will drop quite a bit. Then when we warm up the relative humidity will rise quite a bit. So you can see it's a crap shoot. Last minute turnings are rarely circular for very long. If you have an oven that is not cooked in, you could bake it at a very low temp for a few hours, but don't use your wife's oven!

 

[Russianwolf]

soaking in DNA or a microwave can help with drying.

 

[MesquiteMan]

Our year-round average humidity seems to be about 13% which is where you would want the moisture level.

Actually, relative humidity and equilibrium moisture content are 2 completely different things. EMC is moisture level in wood where it no longer gains or looses moisture and it is affected by relative humidity but it is much lower than relative humidity. Here is a link to a chart and calculator that tells you what the EMC for wood is at specific relative humidities and temperatures. The firs one also has an average EMC for various cities around the country.

http://www.woodworkerssource.com/moisture.php
http://www.csgnetwork.com/emctablecalc.html

 

[MesquiteMan]

Here is a pretty good discussion of EMC in wood.

http://www.forestprod.org/cdromdemo/wd/wd4.html

 

[Wildman]

You are just below fiber saturation point normally which runs around 30% for most woods. I would let it hang out for two or three months before trying to turn. The average annual relative humidity in my area runs 85% am & 57 % pm. I can turn domestic woods with MC of 20% and less successfully most of the time. Every now and then, get bit in butt doing that.

I have never turned Hormigo!

http://www.3mlumber.com/lumber/hormigo.htm

 

[Wildman]

Wood does add or lose MC with raising and lowering of relative humidity. Weigh a piece of wood after a couple of days or week of rain fall. That water exchange takes place even after wood has finish applied. Why do door swell in spring, summer, but shrink in winter?

What I turn here, might shrink/crack after a few days in Arizona or New Mexico.

 

[KenV]

I rough turn, paint with sealer and let it sit for a few months Some crack and break, but most are turnable after truing the tenon.

 

[Wildman]

This reference pretty dry, skimming over different sections learn allot about wood. I refer back to some sections allot. Yes, has lots of technical information we do not need to turn wood. Still worth a look.

http://www.fpl.fs.fed.us/products/publications/several_pubs.php?grouping_id=100&header_id=p