Bowl Kilns

[Clarence Sears]

I've heard some conversation that you can set up an old refrigerator or freezer with some light bulbs in the bottom, some holes (and perhaps some other bells and whistles) and use it to dry blanks in 2 - 4 weeks.

What are your thoughts/experiences?

Thanks...

[Frank Townend]

Clarence, may I suggest you do a search on this site for Kiln and, after reading those (and there are several), post any additional questions you have.

[Clarence Sears]

Thanks for the suggestion, Frank. I saw several of those threads. My question was more along the lines of what folks have experienced in terms the results of finish-turning the dried rough-outs v. those that are allowed to air dry. My sense is that this another tool in the arsenal, but wanted to see what people think.

[charlie knighton]

jmo, i believe kiln is more useful for bowls than hf

[Roger Wilson]

While I can't answer your question about actually using a kiln, in terms of building a kiln I think that making one from plywood and Styrofoam is a much more flexible way to go then using a refrigerator. You get exactly the size and shape you want. If you do end up building one either way please post your results (pics please).

See articles on this page for info on building:

http://www.woodturningonline.com/Turning/Turning_articles.html#drying

[David Lancaster]

Thought you guys would like to see my kiln.The little guy unloading it is my Grandson Corbin, works for candy. dimensions 4'-5'-12'

[Toney Robertson]

David,

Wow, that is a lot of bowls.

Thinking about finishing and sanding all those makes me exhausted.

Toney

[Jeff Nicol]

Thought you guys would like to see my kiln.The little guy unloading it is my Grandson Corbin, works for candy. dimensions 4'-5'-12'
Dave, Great kiln! What do you use for heat and do you use a dehumidifier and humidistat with yours? It looks pretty substantial. I need to make one or should I say want to make one and just looking for input too.

Thanks,

Jeff

Jeff

[Greg Haugen]

Here's a picture of a "upright" freezer kiln I made. I've only lost one bowl in it, 70-80 have been through it. I start it with a 40 watt bulb and then after a week or so I'll change it to a 60 watt, later on to a 75 watt. I've been very happy with it and it cost $18 dollars to build along with some drilling time to drill the holes; $9 for the freezer from a appliance store before they sent it away to be crushed and $9 for the light. I'll get a second one soon. Some day it would be nice to have one like David's. By following a moisture meter, apprx. 30 days-35 days depending on species they'll be 6-8% moisture.

[Harvey Schneider]

I am wondering, it sounds as if you load this up in batches. It would be more convenient as a continuous process of adding and removing individual bowl. Do you keep bowls wrapped until you have a batch to dry or do you keep loading until full and then start the drying process?

[Greg Haugen]

Harvey,
It all depends. I'll use it both ways depends on wood availability. I'll add and remove bowls as I turn them; top shelf is the greenest and the bottom is the dryest. It can be used as a "batch" system, I'll start with 40 watt then 60, 75 and possibly 100 watt bulb as a final bulb if they're rather large bowls or stubborn drying species. If I do use it as a continuous system I'll usually stop at 60 watts. I've found it's warm enough to dry a bowl but not too warm that the two top shelves will get too much heat too fast. Most any species that's grown in WI. will dry with a 40 watt bulb in 6 weeks, 4 weeks for a 60 watt-except for White Oak which takes longer. As new bowls are roughed/cored the shelves are cycled down. Since the blanks are dated, once they reach the 3-4 week mark I'll check moisture content and either pull it or leave it a little longer. The winter months are slower here to get the wood so the kiln is used more with this method. During the summer the city and counties cut more so the wood lots are fuller and I'll usually use it as a "batch" kiln. Once I fill it, during that month I'll work on boxes, spindles, and Natural edge green bowls.

It's a flexible and inexpensive system.

Greg H.

[Clarence Sears]

Appreciate the feedback, guys. I think I've developed a "need" to make one myself. Particularly like the idea of picking up an old one from an appliance store.

[Scott Conners]

Greg, do you seal the end grain at all, or just rely on the humidity inside the kiln to keep moisture loss and cracks under control?

[David Lancaster]

Harvey
I load 2 to 3 hundred blanks at a time into the kiln where they will remain for 30 days plus or min.a few days. The unit is a Ebac LD800 dehumidification kiln that I take up gradually to 95deg Far. Once the door is closed it is never opened until the process is done. It's done when the water stops usually 30-40 gal a load. You can't add bowls as you go it defeats the principal. How this works is you heat up the wood and the moisture goes int the air in the kiln the dehumidifer removes the water from the air until the wood and the air reach a low relative humedity.If uou add bowls as you go the humidity will remain high and they will only dry as fast as the greenest bowl say nothing about cracking the bowls in the unit when it is hit with that blast of air when the door opens.I have been using this method 1992 and have dried and turned thousands of bowls in it.If I lose one bowl a load it's a surprise
Don't forget you need humidity in the chamber if it isn't there your too hot or you don't have enough bowls in it to make enough moisture, You can add a pan of water to the bottom of the kiln to help
hope this has helped
.

[Greg Haugen]

Scott,
I seal all of the outside and none of the inside. It dries from the inside out, similar to the Den. Alcohol soaking method and wrapping the outside with paper. When I used the alcohol method I found there was less warping with creating the internal tension-it's holding true here too. This is a method and the layout of the kiln I built came from Kelly Dunn, who lives in Hawaii. He's used this method for 20 years and has had excellent success with it. Being from WI., going by Mahoney's "2-3 months and they're dry" method doesn't work since he lives in a desert and WI is alot more humid. When I heard about Kelly's method and knowing he's from HI, I had to give it a try. I've been really pleased thus far. This method works more on the "air flow" principle than the dehumidifier factor, the light heats the air, warm air rises-as it rises it pulls air through the holes on the bottom and pushes it out of the top. The warmth along with the gradual air flow dries the bowls. And since the air rises and the greenest bowls are on the top, their humidity never gets to the bottom bowls-if it's ran in a "put some in, take some out" method.

David's kiln is absolutely incredible! WOW! Some day it would be incredible to have one that style. I once saw a picture of Trent Bosch's kiln that wasn't that large, I think, but the same principles.

Greg H.