Talk Composites - The Forum for Advanced Composites

MDF Plug sealing and building MDF oven

http://www.talkcomposites.com/Topic37772.aspx

By Dentex - 9/3/2020 12:47:23 PM

Hy guys,

I have plug made from MDF that was CNC routed.

I've read that it's really hard to achieve gloss surface if MDF is not impregnated and "sealed" properly. It's hard for me to find products that are used for example in America and I have to take DIY approach. I figured that it might be possible to use polyurethane 2K varnish but diluted 20-30% so MDF can soak it easily.
Does anyone have similar experience? 

Also, I saw some DIY ovens made completely from support frame and MDF panels with rock wool between outer and inner panels. My plan is to build wooden frame, put 12 - 16mm MDF for outer shell, place rock wool around box from inside and than make smaller box that fits in from steel sheeting of aprox. 1-1.5mm thickness. I would make it so it opens from top side like a lid. I need curing temperatures of around 110-120°C (aprox. 250°F). Inner dimensions would be 160x70x50cm and I was thinking about 3 to 4 heaters of 1kW strength. 

Will this kind of build be ok to withstand those curing temperatures because I am afraid of oven catching fire? 

Also, I am looking for good PID controler with ramp and soak function so I can make proper curing cycle for pre-pregs. I've found some OMEGA controllers, but I am not quite sure what's good and what's not so please if you have suggestions feel free to write.


By Hanaldo - 10/19/2020 1:07:09 AM

 
Dentex - 10/18/2020 3:04:03 PM
If I can understand properly on eBay, all those heating elements are replacements for some kitchen oven models. That's the same thing as I was thinking to buy here. Find some reputable store that sell replacement parts for ovens and buy it. If that's correct I will avoid postage cost and waiting part. 

What is in the box with Omega CN7800? It would be of great help if you can tell me what SSR and what thermocouple to get since I really have 0 experience with those elements.

Yes exactly, replacement parts are perfect. 

The CN7800 is just the controller in the box, nothing else. SSR you need a low switching high type. So 9v input switching a 240v output. 

Thermocouple a K-type with the correct temperature range is ideal, and then you just need to set that up in the controller when you get it. Very easy, the manual will tell you how.