New Oven!!

[taz575]

Built this Heat Treat Oven and took it for its first test drive. 25 minutes to reach 1000 degrees!

27" deep, 7" wide and 6.5" tall chamber, 3800 watt element on quartz glass tubing across the chamber.

This sucker will cook hot dogs damn quick!

[XexoX]

Pizza oven!

[taz575]

Narrow pizzas only! Stromboli or calzones maybe? Or a tenderloin?

[trancher]

Narrow pizzas only! Stromboli or calzones maybe? Or a tenderloin?

No chickens, though! They are unworthy and foul.

Nice work. Looks like you are getting to the point where you have a complete workshop of your own. So, how many blades can you treat/will you be treating at a time in there, Taz?

[taz575]

I can do probably 3-4. If I oil quench, I gotta let the oil cool back down. Air/plate quench, I can do them in succession once the plates are cooled down. Gotta find thick aluminum slabs and something for the cryo!

[ChefKnivesToGo]

You guys beat me to the pizza joke!

[Bensbites]

Nice job. Really great job Knowing what I know now, I would have built
My own. My 18 inch oven does 99% of what I want. After a client handed me a large butcher knife for a rehandle. I want one. I may have to outsource that heat treating. 16 inch blade, plus handle.

[taz575]

Yeah, I was debating between 22.5-in chamber, or a 27-in long chamber. I sometimes do long slicers, and I want to do some larger choppers so I decided to go longer and be able to do everything in this one, including my long shechita that run about 23 or 24 inches long

[taz575]

I took it up to 1910 degrees a couple evenings ago, took a little over 2 hours I think? 4 of the glass tubes ended up breaking, and the element broke when I was trying to extract the tubes. The tubes were a very tight fit to the coil, which expands/contracts slightly with heating/cooling and the tubes were under some tension from the coils not being spaced exactly right. So I have new smaller OD tubes and a new element en route and will be making a new jig to get the element coils properly spaced this time!

I did rig up a way to hold the door closed tighter, but there is still some heat leakage, so I got some ceramic rope to use as a gasket around the door itself.

Some pics from the building process!

[daviddg]

I can do probably 3-4. If I oil quench, I gotta let the oil cool back down. Air/plate quench, I can do them in succession once the plates are cooled down. Gotta find thick aluminum slabs and something for the cryo!

Other than space - have more oil quenching containers?

[taz575]

I want to get taller and wider containers; I have a 4" square tube and 6" cylinder, both 24" tall. I want to go up to 33" or so tall and both 6" diameter containers, so I am looking for something about that size that isnt super expensive! They will need a bit more oil to fill up, but I have most of it already.

[daviddg]

Check out new larger scale construction sites in your area for steel/iron water pipe. I don't know how many cutoffs/scrap they end up with, but you may luck out. Even if they are small, you can stack and weld them together to get your length. Don't know if TW EMT (thin wall electrical metallic tubing) would work for you but that is substantially less expensive. HW/Rigid EMT would be very unlikely to be found. Also check out any local steel warehouses for plate. You may very likely find scrap pieces there on the cheap. Nice oven.

[Lloyd Harner]

nice easy bake knife ovven i upgraded my 18" even heat to a 22" LB style a few years ago. if i need longer then that im going to a friends shop that makes swords. my EH will take aboout 2 hours to run XHP thats with a 10 min soak at 1500 and 20 min soak at 2000f so your kiln is doign just fine.

[taz575]

Its around 2.5 hrs to get to 1900. I did seal the door better. I ran the oven for a bit, shut it down and then lifted off the kaowool on the top and saw my little 1"x1" block shifted a lot and left gaps. The top kaowool was much hotter than the sides and back, especially with the coils in the roof.

I checked and am.getting 233 volts off of the ssr to the element legs, so the power is getting to the coils.

Since its coil over tube, I milled grooves into the brick for the tubes to sit into, so I am going to stuff kaowool into the grooves to fill those gaps better. I also cut fire bricks down into 1.5" tall slabs (3 per brick) to seal up the top better instead of the 1x1 pieces. I may get some insulwool board for the top, too since that seems to be where my heat loss is mostly. W

[trancher]

The gray electrical box, with the two position rocker switches, fuses, and digital display, was that something that you assembled/soldered up separately, Taz? Looks good, well laid out.

[taz575]

It's a project box from Amazon and I did the wiring and stuff myself. Red Beard Ops on youTube has an excellent oven build and I got the box wiring info/schematic/parts list mostly from his build.

The terminal blocks inside made the wiring much neater than the typical wire nuts! I went with a larger size project box because my heat sinks/ssr's were a bit over 6" tall, so I needed a 7" tall project box and I wanted more room to loop the wires around.

Wiring guts:

[trancher]

Very nicely laid out and awesome wire management job! Box looks like it has plenty of room for accessing. You're quite handy!

[taz575]

Glowing at 2000 degrees! Took 2 hr, 40 min to get there, but I finally figured out why! My bricks are 2.8# or around 55 lb/cu ft. K23 are supposed to be 2# or around 36 lb/cu ft. These are 40% denser and take a lot longer to heat up. Carbon steels it isn't too bad to get to temps, but I am going to hold off on stainless steels I think until I get a chance to get the correct K23 bricks. Amazon has these labeled at K23, but they are MUCH denser than even K26 bricks are!