Heat box temp

[wappkid]

I am new to building bows.I am atempting a take down recurve.My shop does not have any heat in it today it was around 35 degrees in the shop.I got my heat box done and tested it.I have 3 200 watt bulbs and one 300 watt bulb.I got the temp to around 140 degrees.Is my shop temp affecting the heat box temp.If I put a couple of space heaters on it would it raise the temp of the box.

[Eric Krewson]

Insulating your box would probably get you all the temp you need.

[wappkid]

What kind of insulation

[Dick in Seattle]

I insulated with a very effective bubble and foil material available at builder supplies.  I put my first bow in this afternoon.   The plan I built from called for 4 200 watt bulbs.   I used three but got a temp of 190.  I dropped back to three 150's and got 160, which I still thought a hair high, so I put in three 100 watt bulbs and it hit a steady 140.   I did not use a thermostat.   Construction details are at:

 http://dickwightman.com/archery/bowyering/ovenpix/oven.html

[wyatts daddy]

My oven is made of plywood, it is 12" wide by 24" high and 8' long. It's lined with tin foil. I use 3 200 watt bulbs wired seperately so I can control the temp. What I did is drill a small hole in the top of one side and the bottom of the other side of the box and I placed two small ac thermometers from an auto parts store ($5.00 each)in the holes. I plug in the box about an hour before to warm the laminations before glue-up and by that time the temp will be what it will be at for the whole cooking time. Here in Arizona I don't have to worry about the cold as much as other places but I work alot at night and my workshop is on my back patio so it does get down to the 40's and 30's in the winter. In the summer as you might know it gets well up to 110 to 115 so this is why I wired the box seperately to keep the temp between 150-180 degrees, (according to smooth-on glue recommendations)cook the bow for 4 hours at these temps. I hope this helps.
Thx Bill
P.S. Total cost of my oven $50.00

[Pat B]

I used 1/2" foil backed insulation board on the sides and top of my box. Use an insulation that can take the heat.    Pat

[Eric Krewson]

I used cheap, foil backed foam insulation on my drying box, same as cooking box on a smaller scale.

I could only get it to 90 degrees with 3 100W bulbs before I insulated it. With insulation I have to turn my rheostat way down to keep the box below 120 degrees, with 3 60W bulbs.

 

[fast_arrow]

Hi all!

My oven is 200/40/50 cm and is insulated with 3 cm polystyrene I use for heating a hair dryer of 1200 w modified and inserted in a metal tube to guide the air:

 

 

It take just few minutes to come  at 60-70 C.

I use a bimetallic thermostat:

 

I have two holes in the wall to see inside the box and a bulb that is turned on just to see inside:

 

The highest temperature that I could achieve is 98 C   when the thermostat from hair dryer turn off. I could remove it to get a higher temperature but not necessary. I prefer the way with hair dryer because the temperature is spread more even in the box since air is moving.