Building Heat Treatment Oven from radiators for glass ceramic hotplates ...........

[Natlek]

Ok, broke the glass and I bought a new set because I could not find only a glass . Now I have four plate to play with ....two of them are 200 mm Dia and 2000W each , the one on the right in the picture more quickly heated ... . Now I have two ideas .The first is a classic , building with a refractory brick /already I have them enough / . Of course I'll buy all the necessary electronic parts for temperature control ......The question is whether wire from one plate is enough ? Paragon KM-14D is 1920 watts , and its dimensions inside are more than enough to me ? If one is not enough, I can combine with another one of the smaller?

Second idea ............. silly one

Drawing will explain more, but I'll try with words too . What do you think if I put together these two 200mm ,2000W plate /only this fast plate will work , from another one I will take of spiral wire / next , make a opening for blade and of course I will buy all the necessary electronic for temperature control ?? 200mm length for blade inside is enough for my needs .I am most worried about whether this material can withstand the temperature inside ?

 

[Stacy E. Apelt - Bladesmith]

Before you go too far, consider if those are designed to radiate heat or maintain it. In an oven, everything will be at the oven temperature ... including all connectors, TC, and control parts.

For a tempering oven, I think you may have something. For a HT oven I see bad things.

 

[Natlek]

Before you go too far, consider if those are designed to radiate heat or maintain it. In an oven, everything will be at the oven temperature ... including all connectors, TC, and control parts.

For a tempering oven, I think you may have something. For a HT oven I see bad things.

Well, I think maybe it will work. I experiment a little today. ...I connected electricity directly to thermocouple .The temperature achieved very, very quickly.I do not know exactly at what temperature thermocouple is turned off , but it remains a long time off . I left turned on for about an hour without knife , means completely closed, nothing bad happened inside .Heated only one plate, the one down . Then I connect the heater directly to electricity without thermocouple , but only for a short time because temperature rises too fast .....I think I'll order the necessary Electronic /digital temperature controller,Type K Thermocouple ..../ and try. If there is none of these idea, I will build a classic oven/kiln , I already have briks . . I like this idea because I think that inside will be reduced atmosphere ?

 

[Stacy E. Apelt - Bladesmith]

Seriously ... you are putting a metal blade over a metal coil with a deadly amount of current running through it ... seriously!

Have you really thought this out?

 

[Natlek]

Of course I thought I used insulated pliers and I was very careful about what I'm doing . If.......... if I make this , working plate will be UP , so there will be no chance to hit the wire .And I will put ring from the same material to increase height / volume/ inside . There will be enough place , since from the lower plate I will remove the heating wire . And if even blade touch wire it s not as dangerous .It s already a closed circuit ..... ? At the end , it is easy to put some protection inside .......we'll see, I'll try ,remains only to choose and buy the necessary electronic parts.

PS . In the picture blade does not touch the coil. Stand on the thermocouple .........

 

[Natlek]

Seriously ... you are putting a metal blade over a metal coil with a deadly amount of current running through it ... seriously!

Have you really thought this out?

Well, perhaps it is better to delete this topic? I do not want to bear the responsibility if someone try something like this and something bad happen.

 

[JTknives]

For some strange reasion this seams like somthing I would try to do back in my younger days.
If you look at real heat treating ovens thy disconnect power from the coils as soon as you open the door. I think this project of yours could work but it would involve using the heating elements as just that. Get soft fire brick and build a small heat treat chamber and use the burner as the heat source. What Stacy is trying to do is protect you and others from becoming crispy bacon. Safety is key especially when we are talking about somthing that could well kill you.
The exposed elements in them selves are not bad as thy are exposed in a heat treat oven. You just need to come up with a way to isolate everything and keep you from touching the coils with the blade and not have the tang exposed while heating. A little tip, if you do get is working and safe you are going to want to heat the blade with it reasting on its spine. If you heat while laying it flat you will get warps.

Just be safe.

 

[Natlek]

JTknives , I wrote that this is only a test , experiment. Of course I would do everything right if I decide to build this . Safety is first , I am a mechanic almost my whole life Of course that blade will rest on spine , that's why I wrote that I would increase the height .....

 

[Natlek]

Well , I do not give up so easily What do you think about this ? What if I separate them with two brick / 2.5 inch thick / like on this drawing ? Can be heated up to 10 inches long blank , which is more than I need . I will use all the necessary electronic , thermocouple ..etc ? BUT no door , just opening for blade ? Of course I can make to disconnect power from the coils before insert blade inside ... From what I have so far tested 3.5mm 4 inch long blade is ready for quenching for about a minute , is it good that fast heathing steel ? What do you think about this new idea ?