heat box plans?

[deermaster]

does anyone have plans for a heat box for curing epoxies like bowgrip 100 and smooth on? i would like the plans and your method for regulating the temerature.thanks for any info!

[Jesse]

I dont have plans Ive used recorsinol glue without high heat but Im prety sure all you need is a piece of stove pipe, a cheap heat gun, and a thermometer. Im sure someone else will give better instructions than this.
                                                                                  Jesse

[Pat B]

I got my plans from Bingham. I use 4, 200w light bulbs with a 168deg thermostat from Binghams. I usually don't need it that hot so I unscrew bulbs until I get the heat down where I want it. One light bulb will keep the box at about 100deg. My box is 3/8" plywood and I added 1/2" foil backed insulation board to all sides, a fan inside and a 1" hole at each end for venting moisture when drying wood. I plug it for heat curing glue.    Pat

[duffontap]

"Hot Box Wood Dryer" by Greg Harris Vol. 3 issue 3.  Check the store to see if the issue is availible.  It may not be.

         J. D. Duff

[rudderbows]

An easy oven is some 6" single walled stove pipe and a heat gun, ( any heat source that can stay on for more than 4 hours is good including propane blowers. Use a cheap meat thermometer on the far end from the heat source to tell you how hot the air is exiting the pipe. Back off the heat when it hits 185-200 degrees.  Cook for 4 solid hours after getting up to speed.  MAKE SURE TO KEEP THE BOW AT LEAST 2 FULL FEET AWAY FROM THE HEAT SOURCE OR IT WILL FRY. !! Use 8 feet of stove pipe.
 Wrap it completely with shrink wrap to keep it from drying out. That's how we do our bows when we are curing only one or two and it works great. We use a much larger box for larger numbers of bows, but thats a different story in itself. Hope this has been helpful.

[tradrick]

PatB,would the type of box you have be better suited for force drying a stave for bow building.Such as leaveing a stave in there for a week or two at maybe a lower temperture but have constant heat on it.I'm refering to drying hickory.Thanks tradrick

[duffontap]

I use my hot box to cure selfbow staves.  Mine is just a 7' x 18" x 18" box with 4 basic porcelain fixtures.  I use 4, 60 wt. bulbs and the whole system is on a dimmer switch.  I dim them way down to keep the temp below 100 degrees.  It saves a LOT of money on your power bill and the light bulbs last forever when they're dimmed down (as opposed to two weeks when they're not).  You wouldn't think it, but the cost of electricity and light bulbs can really add up if you don't take pains to be efficient. 

          J. D.

[tradrick]

Thanks J.D. I've got a pretty good idea of what I need now.Learning alot from this site and lovin every minute of it.tradrick

[Pat B]

I added the 1" holes at either end of my box(one on top, the other on bottom) to allow moisture to escape while curing staves. A small fan inside helps to dry the wood quicker also. Each box will be a little different depending on temp and humidity so when you get one built you will have to tweak it to suite yourself.    Pat

[deermaster]

thanks for the help!

[Justin Snyder]

Wow JD, under 100*, I need to put an air conditioner in the box to get down to 100*.     On a serious note.  The dimmer switches have been shown to use the same amount of energy.  The energy not used in producing light creates extra heat in the switch itself.  Use 40W or 30W bulbs if you want to save energy and reduce heat.  Justin

[duffontap]

Really?  I before I switched to the dimmer switch my energy bill would spike on months I was using the box.  I may be reading into it.  I'll do a little research. 

      J. D. Duff

[duffontap]

Justin, I think that only applies to old, non-transformer style switches.  I'm not sure but the consensus seems to be that it does use less energy.  If the energy is being absorbed by the switch, that would be a huge fire hazzard.  Scary thought. 

(Online sources, note what they say about bulb life too!):

8. Do Dimmer switches save energy?

Yes, most dimmers today do save energy. Older dimmers used to simply cook off the power you did not want to use. Today's dimmers interrupt incoming current thousands of times per second (invisible to the human eye) saving 10% in energy costs even when on full, the life of your bulbs is also greatly increased.

From "8 ways to save energy":

Want to affect the mood and save energy? An effective way to quickly change the mood of a room is by dimming or brightening the lights. A softer light results in a more comforting, relaxing atmosphere. Brighter lighting is more suitable for normal room use and reading. An easy way to control your lighting is to install a dimmer switch. Dimmers also reduce energy consumption by cycling light and increasing bulb life.

Most dimmers cycle the light on and off 120 times per second – faster than your eye can detect. The longer the light is ON versus OFF, the brighter the light output. Likewise, the longer the light is OFF versus ON, the lower the light output and the greater the energy savings. An added bonus is the incredible increase in bulb life from operating at a lower light output (filament temperature). Dimming the light by just 10 percent more than doubles the bulb life.

[MattE]

Why would you want a dimmer switch on a heat box when you can use a thermostat instead? You still have to check your temperature if using a dimmer switch, you don't with a thermostat. You can buy a thermostat but any used one will do, they hardly ever wear out. Toaster ovens, water heaters and any appliance that has a heat control knob has one. I personally like water heater thermostat and you get two from them as well.Think thermostat not dimmer switch!

[Pappy]

Good idea Matt,I now and have for several years used a dimmer set up like JD but my boxes are out side in my bow shop so I am constantly having to adjust the heat when the Temp. changes
so I may give that a try.I guess if the box was in a controlled temp. you could pretty much set it and would stay about the same but mine is not.
   Pappy