I've been using a steel filing cabinet as a powder coat oven which has worked ok but not as good as I need it to. I need to insulate it better and have been looking at the rigid ceramic boards, there's a company in Newark that list on eBay and also mention 'Aluboard' which is a insulation board with a reflective aluminium foil on one side. Unfortunately ive called them twice and both times was assured someone would call me back....no one has bothered which makes me think they can't be bothered with my enquiry, probably not going to make them enough money. Has anyone used this sort of board for a similar project? The cabinet is just single skin, I'm also looking at putting 2 or 3 electric elements in it and having a control panel professionally built. Any comments or possible suppliers of the insulation board welcomed.

Are you wanting to insulate the inside of the filing cabinet?

If it's the outside of it can you not strap the loft board type stuff to it? Surely be a lower cost way of doing it.

Failing that have you looked around on ebay and likes for 2nd hand kitchen ovens? A quick look on there shows some for less than £50.




[Edited on 9/12/19 by nick205]

How bigger item do you need to bake?

Size of items vary really, I'm making log baskets which can be up to 800mm tall down to plant stands etc which are much smaller. The log baskets mean a 2nd hand kitchen oven wouldn't be big enough.
My cabinet is 1800 tall by 800 wide, I'm hoping to extend the depth of it to around 600 If possible. O would like to start making railings too so might be looking at coating those too...Sizes depending. My initial thought was to insulate the inside of the oven rather than the outside, may have a think about that.

Have a search for vermiculite board, or that's what I think it's called!
Best to put it on the inside of the cabinet, but it's a brilliant heat barrier.
Not sure how cheap it is either!

Thanks for the replies, I'll have a look at the vermiculite board

[Edited on 10/12/19 by Barksavon]

Ceramic fibre board is a rubbish insulator. It is very heat proof and I lined the inside of my filing cabinet powder coat oven with it. Mine is lined on the inside with glass fibre insulation blankets, then a layer of ceramic fibre board then two layers of tin foil. The walls are about 40mm thick. In my opinion it probably doesn't matter how much insulation you have the outside will get hot eventually. The tin foil made the biggest difference for me.

I have a 3000w element from a cooker and a fan for air circulation obtained from a free oven off Facebook. I control the temp by a PID

The wiring is dead easy and you actually could just replicate the wiring from and oven

It did scare me a bit as 240v is a lot more than 12v!!

I did consider a vermiculite cement mix for the walls. You could lay it down and spread a mix over the bottom on the inside. Once dry then turn so a different side is on the floor and repeat. I didn't do this because I was unsure of the final weight.

Great info, thanks. My oven started life as a filing cabinet.
I'm hopefully going to get some advice from a company called Studweld Pro about the most suitable material to use (after emailing them about their lack of response to my calls)
I'm looking at something called Aluboard, which is a ceramic board with aluminium foil on one side. You don't have any wiring diagrams do you from when you wired yours up?

I used a inkbird PID controller kit from Amazon. It included the controller, relay and sensor. 25 amp relay.

linky

Great, I was just going to add on to say I was particularly interested in the PID to control temperature. Did you also use the timers, element and fan out of the old oven?
Does it get the workpiece to 180 c and hold it there for the required 10 mins, my coating looks ok but it chips very easily which I think is due to under curing
Sounds like you've done exactly what I'm planning to do

[Edited on 11/12/19 by Barksavon]

The oven has zero issues getting up to temperature. It's a three drawer cabinet with a 3kw element. Gets up to temp in 10 minutes which is faster than a conventional domestic. Well the temp sensor reads say 180 but things I put in the oven don't seem to get up to a even temp. I am experimenting with a spanner on a hook at the moment. The oven is set to 165 and the temp reading is always within 2 degrees of that. However the workpiece according to my laser temp sensor is 150 at the top and 180 nearer the element. Big difference. It's a 400mm long spanner and the bottom bit is at least 250 from the element.

I used the element from a oven and a inkbird PID kit. I also used the fan from the oven to help even out the temps. Not sure the fans helping though!!