Very nice unit. Where were you when I was scronging around for scrap ovens?

I would have bought this in a heart beat. 

Thanks for posting.

Fred 

I use one of these: ebay link and it works very well... so easy to use!




Alessandro

Nice job.

I pulled the guts out of old kitchen ovens for my heating oven and my autoclave. Its the thermostat bulb and control I needed. I have this control activate a relay that controls the power to my heating eliment in the autoclave. My heat box has a 2000 watt space heater in it. Works great.

Fred 

@CarbonMike - Have you had an oven catch on fire on you? I would be interested to know what you think went wrong and any tips on how to avoid would helpful too!

Aaaah, good old box ovens lol

Awesome when they work, catastrophic when they set on fire :/

I have found that the oven I built from an old metal storage cupboard works very well. I took an old 1.8m tall storage cupboard and clad the exterior with 50mm Celotex building insulation including the doors and then fitted the heating element, fan and thermostat / temp controller from an old domestic fan oven. I have found that it easily holds 100 degrees + or - 4 degrees and I monitor it with an RS components temperature probe to keep it just right.

if you live in sunny climates the sun can help kick it off. but if you do it too soon it can cause air bubbles so not the best idea. i suppose if it were 2nd
day and your part is still a bit soft the sun would likely be ok but be careful and monitor the part.
the automotive refinishing industry has many infra red heat lamps, from 150.00 dollars to 4000.00.
i suggest if you use heatlamp keep it 3 feet away. once the resins are warmed they will go off and
as it's exotherm happens it generates it's own heat and finish on its own.
so if you can warm it up and help it along, cool. i am sure like auto paint the whole chemical process
stops at low temps and will finish off once the temps come back up.
  so if you leave the part in the shop leave the heat on.
also ambient air temps are usually 15 degrees more cold than your part temps which will effect your cure times.
so you MAY be in the range for your hardener and catalyst type and quantity based on ambient air temps, but the parts
and mold temps will be lower so be aware of your work area temps.

so in all our learning something as simple as shop temps and resin selection and catalyst are very important.
i have a sample of epoxy incompletely mixed for 10 months and it is dry to touch, but soft and flexy. temps and
complete mixing is very important.

CarbonFiberCreations

This thread is really useful - thanks for posting your experiences to date!
Although I found an electric blanket worked well to elevate temps for curing/post-curing in the summer its nowhere near warm enough in my garage now so I'm planning an oven that sounds very much like your v2.

Ducting from opposite end to fan heater for air circulation and minimise temp variation, Digital PID temperature controller with thermocouple, output to a solid state relay to drive the fan heater element.  Safety cut-out at 85 degC to turn the whole lot off.
Oven construction will be foil backed foam sheets, chipboard base with an extra layer of rockwool (loft insulation) as that is so cheap in the UK.
Fan, controller, relay is £40-50, ducting, foam sheets & chipboard I already have, rockwool insulation probably £15 so should be pretty cost effective and will let me cure parts properly in the garage all year round.

I'm thinking a 2kw fan heater should provide plenty of capacity for the planned size of 1.25m3 (assuming that the oven is pretty leak-proof) but any other views appreciated (I noted you were using a 6kw space heater but surely that must have been on a very low setting or not recycling the air)?

I'll update as I have more to share.
Stuart

None yet! Unfortunately lots of things have come up in the last week and so i haven't had time, i'm going to be redesigning it in the next few days hopefully.

The chest freezer idea is interesting! However finding one that has a large enough internal capacity could be hard to find.

Dave

Any updates of your oven?

 



 


    A $1000 electronic device will always protect a 10 cents fuse