PDA

View Full Version : oven drying



weisyboy
14th Aug 2007, 10:09 PM
has anyone tryed to dry timber in a gas oven??

if so what were your results??

Skew ChiDAMN!!
14th Aug 2007, 11:04 PM
Too hot, too dry, even as low as it goes, with no real success. Cost a fortune in gas, too. You're better off using a drying cabinet: just a low wattage light-bulb in the bottom of an old microwave cabinet or similar.

Been covered pretty well in these forums, I reckon...

joe greiner
15th Aug 2007, 01:18 AM
Ditto what Skew says. Even at lowest setting, actual temperature varies wildly as it goes super hot until the thermostat shuts it off, then drifts down to the on signal.

Joe

Sebastiaan56
15th Aug 2007, 08:17 AM
Also, when gas burns it releases CO2 and water, so the humidity in a gas oven is always high when its burning,

sebastiaan

weisyboy
15th Aug 2007, 08:23 AM
ok will investagate a hot box.

wattlewemake
15th Aug 2007, 11:59 AM
Weisyboy do a google search for solar kilns. Wood web had a few different designs dependin on how much you want to dry.

Shane.

Gil Jones
15th Aug 2007, 03:25 PM
Weisyboy,
Attached is a Word doc from Cindy Drozda on how to make your our kiln cheaply. I also have the file in pdf, but it is just barely too large to upload here. If you do not have MS Word to open the file, go to Microsoft's web site and download the free viewer (or pm me your email address, and I will send it [or the pdf] to you).

weisyboy
15th Aug 2007, 03:44 PM
thanks will read it and maby give it a go.

Frank&Earnest
15th Aug 2007, 04:48 PM
My apologies if this has already been done to death, but I have read the Drozda doc and she says that at 85 degrees F (less than 30 C) it takes 6 days to dry a roughed bowl. Which means that even in temperate Adelaide one week in the shed in summer is enough to dry out everything, with a bit of cautions to keep the temperature reasonably constant. She says that Colorado is dry and warm ... was the room temperature so far below to warrant the cabinet? Is it only a winter proposition? Am I missing something here?

weisyboy
15th Aug 2007, 05:00 PM
My apologies if this has already been done to death, but I have read the Drozda doc and she says that at 85 degrees F (less than 30 C) it takes 6 days to dry a roughed bowl. Which means that even in temperate Adelaide one week in the shed in summer is enough to dry out everything, with a bit of cautions to keep the temperature reasonably constant. She says that Colorado is dry and warm ... was the room temperature so far below to warrant the cabinet? Is it only a winter proposition? Am I missing something here?

typical americans.:roll:

echnidna
15th Aug 2007, 06:53 PM
might apply if the roughed bowl is thin enough

Frank&Earnest
15th Aug 2007, 07:15 PM
"A thick x 6 diameter, open bowl blank, of Honey Locust, with sealer on the endgrain".

On a second read, I noticed that she claims that the drying time is only reduced to 1/3, which would seem about right. But is it worth then? 120w x 24h x 6d = > 17Kw. I'll do the ecologically sound thing and wait 18 days.

Skew ChiDAMN!!
15th Aug 2007, 07:17 PM
The key is the thickness.

I'm sure we've all heard the rule of thumb for air-drying: 1 year for each inch of thickness? And this is regardless of what climate we're in? (Except for extremes, such as the high tropics or antactica, of course.)

This still holds true for a hot-box, in general terms, if the timber's thick enough as the moisture still has to migrate out from the centre of the wood. Where the hotbox is practical, is for thin pieces... such as pen blanks, veneers or roughed blanks which are of an inch or less wall thickness.

ie. You can't slap a 12"x4" solid blank into a hotbox and expect it to cure in a matter of weeks instead of years. :rolleyes:

hughie
15th Aug 2007, 07:59 PM
Yep, what ever you do with wood slow 'n steady is the go. A bit of an anathema for our instant society. :U

rodent
15th Aug 2007, 11:16 PM
I'm using an old clothes drying cabinet the heater in it is to hot so I've put a 75 watt bulb in the bottom ,cardboard in the top and wire shelves in it . I was looking every where for one and at hard garbage there it was three doors up the road with a broken hinge (so what) dragged it home . And i mean dragged it home its all steel and heavy .put the globe in stuck a thermometer in it .I left it on over night and the temperature stayed stable at about 27 deg C .

Frank&Earnest
15th Aug 2007, 11:58 PM
OK, OK, I get the message. Instead of switching on the electric oven I meant to try, I'll replace the oven light with a 75w bulb and leave it on!:D

Skew ChiDAMN!!
16th Aug 2007, 02:58 AM
I reckon it's best if the light bulb is located at the bottom of the case, as that sets up adequate air circulation currents without needing the overhead of fans. Also, IMHO, 20-40W bulbs are all that's needed and cheaper to run in the long haul but, as with anything, everyone has their own preferences.

So long as you don't expect miracles from the first run, and are prepared to experiment around, I'm confident it won't take you long to have something set up to your satisfaction. :)