Paragon Kiln

[3fifty7]

A local guy has a couple Paragon electric kilns that he is looking to sell. He knows NOTHING about them(I honestly don't much more than him). He got them cleaning out a couple buildings. He does not I know if they are in working order. I may be able to bring them to my shop and plug them in.
I'm a hobbiest bladesmith at best and have been heat treating in my forge on a wing and a prayer. I've had grain growth issues before and hoping to fine tune that some what.

If you have any thoughts suggestions on these kilns and a working & non working value would be greatly appreciated. Also any recommendations on what might need to be added to them.

Thank you

 

[3fifty7]

One is approximately 2'X2'
The other is approximately 2'X3'

 

[joedhiggins]

Kilns are not great for HT because they are not designed to be opened hot. You can make it work, but realize that you may have to repair it sooner than a HT furnace. I would add a PID and dbl check the thermocouple, replacing if necessary.

 

[JTknives]

I can see a specialized use for an oven like these for heat treating but for a hobbyist it’s way to much oven. I have considered getting one and moding it into a semi production oven. Would have a small opening in the top and a carousel above it that would turn and go up and down. I would string knives on wires and it would run off an arduino. Every x min it would lift up and rotate and go down. This wound soak a knife in the oven and quench the blade it just pulled out of the oven. But that’s only practical for my production needs.

 

[joedhiggins]

I can see a specialized use for an oven like these for heat treating but for a hobbyist it’s way to much oven. I have considered getting one and moding it into a semi production oven. Would have a small opening in the top and a carousel above it that would turn and go up and down. I would string knives on wires and it would run off an arduino. Every x min it would lift up and rotate and go down. This wound soak a knife in the oven and quench the blade it just pulled out of the oven. But that’s only practical for my production needs.

I would probably build an oven for scratch if that was what you waned to do. Or maybe a pid propane oven. Seems like it would be less effort that way.

 

[Stacy E. Apelt - Bladesmith]

That is a pottery kiln, and not really usable for a knifemaker. It would also take a big electric circuit to run it ... 7200 watts! Holy Cr@p Batman.

 

[jdm61]

Didn't James Helm cut a slot in the lid of a kiln? Wonder if you could make a sand pot out of it? We've seen weirder stuff.

 

[Grayzer86]

Didn't James Helm cut a slot in the lid of a kiln? Wonder if you could make a sand pot out of it? We've seen weirder stuff.

Oddly enough, I never thought of using one to try building a salt pot. Honestly that seems like probably the best use of them. Set it up with a PID, cut a hole in the top, and stuff a salt tube inside it. That eliminates the issue of opening a hot vertical kiln and melting your face off trying to get blades out.

 

[3fifty7]

I'll never afford an Evenheat with the small amount of knives I make in a years time.

I know it's not optimal but at what price is it worth trying out? I honestly think he will take $100-$200 each.

 

[Stacy E. Apelt - Bladesmith]

Do you have the power in your shop to run it? Also, make sure you install the right type plug, as it the kiln uses both 120 and 240VAC on a three wire system. You would need a 50 amp double breaker to run it. The wiring from the panel to the socket should be 6 gauge. All this should be done by someone very familiar with wiring and codes.

Honestly, if you are only going to do a few blades a year you would be far better to put the money into the needed equipment - grinders ( belt and disc), a good drill press, files, hand tools, file guides, etc. Send the blades to someone like JT or Trugrit for HT and know they come back perfect with whatever HT regime is best. That will allow you to use any steel type you want with no problems.

If using one as a HT oven, you cut a hole in the top (usually around 3") and hang the blades in on 1/8" stainless hooks. You would use kaowool or soft firebrick to cover the opening in use. You can use the custom search engine in the Stickys to search "pottery kiln HT oven conversion" and tread many past threads on the subject.

They can be converted to PID control by someone familiar with wiring and basic HT controllers. That will run about $150.

 

[joedhiggins]

Do you have the power in your shop to run it? Also, make sure you install the right type plug, as it the kiln uses both 120 and 240VAC on a three wire system. You would need a 50 amp double breaker to run it. The wiring from the panel to the socket should be 6 gauge. All this should be done by someone very familiar with wiring and codes.

Honestly, if you are only going to do a few blades a year you would be far better to put the money into the needed equipment - grinders ( belt and disc), a good drill press, files, hand tools, file guides, etc. Send the blades to someone like JT or Trugrit for HT and know they come back perfect with whatever HT regime is best. That will allow you to use any steel type you want with no problems.

If using one as a HT oven, you cut a hole in the top (usually around 3") and hang the blades in on 1/8" stainless hooks. You would use kaowool or soft firebrick to cover the opening in use. You can use the custom search engine in the Stickys to search "pottery kiln HT oven conversion" and tread many past threads on the subject.

They can be converted to PID control by someone familiar with wiring and basic HT controllers. That will run about $150.

Hell, if you don't care about ramp/soak, you could do it for 30 bucks or so. 60 amp SSR and 20 dollar PID (still an improvement over analog). Still, for 200 bucks, you could just about build your own oven.

 

[jdm61]

Not sure who "you" is, but in the case of "me" I couldn't build an oven for $2 million.

Hell, if you don't care about ramp/soak, you could do it for 30 bucks or so. 60 amp SSR and 20 dollar PID (still an improvement over analog). Still, for 200 bucks, you could just about build your own oven.

 

[JTknives]

Hell, if you don't care about ramp/soak, you could do it for 30 bucks or so. 60 amp SSR and 20 dollar PID (still an improvement over analog). Still, for 200 bucks, you could just about build your own oven.

I don’t see being able to build an oven that would be much of any good for $200. Mine cost me over $1000 to build. Can’t remember exzact my how much but it was a lot. Totally worth it but far from $200. Hell its hard to build a decent forge for $200.

 

[SirSpice]

I don’t see being able to build an oven that would be much of any good for $200. Mine cost me over $1000 to build. Can’t remember exzact my how much but it was a lot. Totally worth it but far from $200. Hell its hard to build a decent forge for $200.

Just the bricks would probably cost $200, unless you were making a tiny one. JT, what was the most expensive part of your oven?

 

[joedhiggins]

I don’t see being able to build an oven that would be much of any good for $200. Mine cost me over $1000 to build. Can’t remember exzact my how much but it was a lot. Totally worth it but far from $200. Hell its hard to build a decent forge for $200.

20 Firebricks - $80
Few feet of insulwool - $12-15
Sheet metal - maybe $20
Kanthal -$10-15
Kiln TC - $12
PID - $20-65 (65 for ramp/soak)
SSR - $10
Heat sink - $4
Wire - Basically free, but lets say $10
Power cord - Free to 50 (I paid 50 for a long 8 GA cord)
Momentary on switch (for element shutoff) - $.5

About $275 for a 4k watt oven with ramp/soak with a long power cord. Sub 200 if you build one that is staying under about 1500 watts and don't want ramp/soak.

That doesn't speak to the tools, and I didn't calculate the cost of a couple pieces of scrap rectangle bar and round bar I used. Maybe throw another 20 bucks in for that, wire nuts, etc.

Now, I used a tig welder to assemble, but there are other options, A plasma cutter to cut out my sheet metal panels, but an angle grinder would work. I used a belt grinder and a forge to mill and HT a cutter for the channel for the element. I used a super beefy clausing drill press with a quill designed for side loads to mill my channel. I am sure I used a ton of other crap to make it happen as well.

I also didn't skimp on part quality. I didn't wire with too-small a gauge. I used heat tolerant insulation on wire where needed. I think that cost $4 for a long length.

But you could do it all on the cheap. You could build a hand milling cutter to cut your channel from a piece of steel and a block of wood. I am sure you could do a no-weld enclosure. Unless I am forgetting a major expense, I think 200-275 is a reasonable price.

 

[joedhiggins]

Just the bricks would probably cost $200, unless you were making a tiny one. JT, what was the most expensive part of your oven?

I paid $5 a brick for K26s. I should have gone with K23s which run $4 a brick at my local brick yard.

 

[Kevin McGovern]

My costs were on par with JTs.

 

[joedhiggins]

My costs were on par with JTs.

Far be it from me to quibble about the cost. And I definitely could see how it goes up from from my price point by paying more for the bricks, so If someone has to pay $10 a brick, that would get you up toward $400, but I have a hard time seeing how you get to 1k. Maybe a far more expensive controller?

Did I forget some element in my list of materials?

 

[JTknives]

I used a tap controller. My oven is also 5.5”x5”x31.5” long. My sheat metal and other bits and bobs for the ovens body was around $150 I think. Also if running 240v you need 2 SSRS and heat sinks. I then put that all in a enclosure and that was like $70 I think. My element was far from 10-12. It was not expensive but I had it would for me by people that know what thy are doing. I think it was like $50. Then you have your main control breaker on the oven. This is your main power as well as your overload protection. Also don’t forget the switch that turns off the SSRs when the door is opened. To do a oven build right it adds up. And it’s all the little things. Plus most people don’t have access to bricks local and you have to have them shipped. I got K23 bricks and it took 2 cases for my oven. Thy where like $75 each I think shipped. Can’t remember off the top of my head.

 

[joedhiggins]

Of note, one SSR will do 220 just fine. Obviously each SSR has a viltage rating, but because they would be in series they will have 220 (or 250 in my case) running through both. SSR is basically a switchable very high resistance element. Switching both 120v hots will decrease the energy in the off position from almost none to really almost none, but it is definately not required.

I skipped the breaker in the oven because I run it on a dedicated 220 circut with an appropriate breaker in the wall. Not criticizing your decision to get your element wound, but with a simple jig you can wind the element perfectly well yourself.

I included a momentary switch for the door cutoff. I switch the SSR input, not the output which lets me use a small momentary switch. As to length, I have just shy of 24” in my oven body, so you could tack on another 25 bucks worth of bricks if i were to go for 30”.

I clearly payed a lot less by sourcing bricks locally (and from a brick yard, not a ceramics supply). I am sure this is dificult in most locations.

Same for the steel. I used 20 or 22 ga sheet. 1008 cold roll. I think it was 40 bucks for a 4x10. I used less than half. I made the hinges from 1x1/4 bar and a tiny bit of the sheet. I used maybe 3’ of 1/2” round for the hinge pin/door support and a few inches of 2 1/2” round for the counterbalance for the door. No latch because the mechanism held very tightly without. I calculated the cost of the inswool as a percent of what i paid for a large roll.

As to the earlier comment about a forge, if made from round pipe and inswool without brick, the cost of the forge minus burner is about 40-60 bucks with 2” of insulation. The cost of a nice brick lined horizontal (k26 sides and 3000f hard bottom) with 14ga walls is about 120 without burner. I know these because I have made a number for friends lately.