Recommendation? Which Heat Treat Kiln?

[mpcoppin]

I have a Paragon 24” (KM). I love it. It came with the Sentinel touch screen controls. It works great, no complaints.

My buddy has a Hot Shot. He paid significantly less than what I paid and didn’t have to wire a special 220 outlet. He is very happy with it. I’ve used it and I can’t say that there was much of a difference between his oven and mine, other than depth. Mine may have heated up faster but not enough so that it made a difference in my head.

 

[Larrin]

Are they fairly accurate with respect to the set/display temp and do they hold their temps consistently? My current oven is generally 20-30 degF off of the set temp (if I want it at 1465 I have to set it at like 1445) but will hold the temp within about 3 or 4 degF once it gets there. I use a separate thermocouple to watch the temp. Not sure if there’s a way to calibrate the one on the kiln.

How Even is an EvenHeat? How to Operate Furnaces Effectively - Knife Steel Nerds

I measured the temperature distribution in an EvenHeat furnace, and I have recommendations on keeping the temperature even.

knifesteelnerds.com

 

[Larrin]

Would you say that there would be a measurable difference in steel properties with knives heat treated in a fiber kiln vs brick kiln?

The properties are based on the thermal profile the steel sees. So if it is the same it doesn’t matter what material the furnace is made of. If there is a very uneven temperature distribution or some other issue then of course it is anyone’s guess.

 

[LCoop]

I'll give to all the more intelligent folks than me. I built my own heat treat kiln myself. I used Pottery kiln bricks that was damaged from improper glazzing used. It had a additional 2' of insulation on the outside of the soft bricks. It will come up to 1975 in 25 minutes. The outside temp is basically room temp except the door which is single door K bricks. The rebound is incredible. So yes I believe insulation is important. FYI I built a super insulated house that pays for itself every year.

 

[ScarFoot]

How Even is an EvenHeat? How to Operate Furnaces Effectively - Knife Steel Nerds

I measured the temperature distribution in an EvenHeat furnace, and I have recommendations on keeping the temperature even.

knifesteelnerds.com

I don’t understand how with all of my googling the last few weeks I didn’t find that article. Exactly the info I was looking for. I’m starting to think I might get a KO and a tempering oven.

 

[CWendling]

Also looking at upgrading from a 20ish year old paragon 14". Was looking at probably the K018, maybe 22 since ive only ever once not had enough length in my 14. How is the external temperature on the newer evenheats? I see people making it a point on the hot shots which i also looked at. My paragon gets too hot to touch on the outside, but ive just never had a real reason to need to touch it so not sure that is an issue. Other questions would be the controller and safety switch. I know my paragon has one, but i dont think ive ever come close to touching a coil. How necessary is it to those that have evenheats? Looking at Tap controller too. From reading it sounds like its maybe a bit more consistent.

 

[ScarFoot]

Also looking at upgrading from a 20ish year old paragon 14". Was looking at probably the K018, maybe 22 since ive only ever once not had enough length in my 14. How is the external temperature on the newer evenheats? I see people making it a point on the hot shots which i also looked at. My paragon gets too hot to touch on the outside, but ive just never had a real reason to need to touch it so not sure that is an issue. Other questions would be the controller and safety switch. I know my paragon has one, but i dont think ive ever come close to touching a coil. How necessary is it to those that have evenheats? Looking at Tap controller too. From reading it sounds like its maybe a bit more consistent.

I don’t have a ton of run time on my KO27/LT27. As I type this I’m normalizing some steel at 1675 and I can touch the outside of it but it isn’t pleasant. It’s not like it’s going to blister you if you brush up against it though. I don’t think it would heat a shop up enough to matter but I mounted mine on a cart so I can do my heat treating outside in case something goes sideways. The Tap 2 controller is nice. Being able to create and modify firing schedules and monitor temps and everything on my phone is nice. The LT oven has the icon controller on it which isn’t nearly as fancy but it’s fine for a tempering oven.

 

[SirSpice]

I have an older Evenheat KH418 (120v, 18 inch), and a HotShot (240v, 18 inch). Both have TAP controllers. The HotShot, in my opinion, is better in every way. The HotShot stays around room temperature on the outside. The EvenHeat gets very hot on the outside, especially at stainless steel temperatures of around 2000. I am much more comfortable letting the HotShot run in my garage unattended (as in, I'm in the other room). The controller safety switch should really come standard on all heat treat ovens. I don't know if I've ever touched the element, but if I'm putting in several knives and shifting them around there is a chance the holding fixture will move and the tip will graze the sides. Maybe that's less of an issue with a wider oven.