Our "oven" was simply part of my workshop about the size of a single garage
divided off with a load of old carpet. As I recall I had 2 industrial gas
blower heaters and a couple of hired industrial fans to provide good circulation
(& hence even temperature gradient top to bottom). We had a bunch of
temperature gauges and thermometers scattered about the place. Once the whole
thing had reached a stable temperature (3 - 4 hours) it remained very constant
(within 2 or 3 deg overall & througout) for the remaining 24 hours, thought I
did have to turn it up a little at night (for reasons only known to us we chose
to do it in mid winter and it was a rather cold night outside). Response to
tweaks on the gas controls was quite quick, the temperature would re-stabilise
within 5 mins. Cost: 2 x 47 Kg bottles of propane + hire of fans & 1 heater (I
own the other one)
GERAINT L OWENS wrote:
> Hi Tony
>
> I have to say my oven was a lot simpler than yours. I simply made an
> 'oven' in my single garage (a.k.a. my production facility) out of 8' x 4' x
> 2" thick polystyrene sheets and taped the gaps throughout with a suitable
> tape. Wings, tailplanes, fin and rudder were all enclosed fairly tightly
> but with good airflow routes throughout the oven. I then made small holes
> each end of the oven at ground floor level to allow domestic 3kW fan heaters
> to blow into the oven. Punched three equally-spaced thermometers through
> the roof of the oven and switched on. Kept a careful eye on the
> temperature on the climb-up, barely daring to leave the room. Had to vary
> the heater power between day and night, but with choice of 1kW, 2kW and 3kW
> on each heater this wasn't difficult. Could also make slight adjustments
> to the temperature by moving the heaters closer to, or further away from,
> the entry holes. From memory I found less than 1 degree variation between
> the thermometers and had little or no difficulty in maintaing a stable
> temperature for the duration of the bake. Everything went just great and
> all it cost me in total was 60 for the foam, tape, thermometers etc. Had
> no deformation whatsoever. Re: your visit to England, I am located in
> Over, Cambridgeshire (about 1 hours drive from the M1) and would be
> delighted to see you if this isn't too far off your track. I am just about
> to put the module in the fuselage.
>
--
Regards;
Richard Meredith-Hardy
rmh@flymicro.win-uk.net
Tel: + 44 (0)1462 834776 FAX: + 44 (0)1462 732668
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