K79 Oven Build

[Sharkey]

Re: K79 Oven Build

Using a halogen light, then heat beads / briquettes before lighting your first low fire seems to be the standard curing method these days. It worked well for me - I only got a small hairline crack.

I like the analogy comparing a crack to a ding in your car door. You will curse when you first see it and you can patch it up as best you can but in the end it won't have any effect on performance.

[deejayoh]

Re: K79 Oven Build

Yeah, I would say keep it 300-400. Slow & low is good, but I think where you run into the most problems is when you let the heat spike up quickly. But at the end of the day cracks don't matter so much. It's like getting a door ding in a new car. Seems like a big deal, but the car still drives fine.

[UtahBeehiver]

Re: K79 Oven Build

K79,

I also agree with DJ on heat beads.

[K79]

Re: K79 Oven Build

I would look into briquets for your next step. They're cheap and I think it is easier to control the heat than with wood. I used sterno for the second step, but it doesn't really get hot enough to do much curing. Bag of kingsford is pretty cheap.

Not a bad idea. You think 4 hours at 235F ish is enought and put in some briquets to 300F tomorrow for about 6 hours?

[deejayoh]

Re: K79 Oven Build

I would look into briquets for your next step. They're cheap and I think it is easier to control the heat than with wood. I used sterno for the second step, but it doesn't really get hot enough to do much curing. Bag of kingsford is pretty cheap.

[K79]

Re: K79 Oven Build

Ok guys I just checked my oven after 4 hours of light and my floor was 165F and my dome was 235F and my cords were getting really soft and I could smell the rubber. I cut the power and plugged the door for now. I'll put the lights to her again tomorrow and hopefully put some fire in it this weekend if my torch comes in at Lowes!

[deejayoh]

Re: K79 Oven Build

Light up my oven this morning for 1.5 hours with my lamps. My floor averaged 115F and my dome peaked at 185F. I'll turn it back on at 4 when I get out of work and leave it on till 10.... we'll see what happens.

you can leave lights on 24/7. Your oven won't get too hot.

[chirobuggy]

Re: K79 Oven Build

looks like your curing process is going well. I like the idea of using lamps for the first leg of the cure. I was thinking I would use one of those BBQ charcoal lighter wands (the one that gets hot like a electric range top coil) but wasnt sure how hot that would take to temp in the oven.
I think I might follow your lead

[K79]

Re: K79 Oven Build

Picked up 8 bags of this stuff to burry my oven in once my enclosure is up:

[K79]

Re: K79 Oven Build

Light up my oven this morning for 1.5 hours with my lamps. My floor averaged 115F and my dome peaked at 185F. I'll turn it back on at 4 when I get out of work and leave it on till 10.... we'll see what happens.

[mrchipster]

Re: K79 Oven Build

I'm thinking of making the decorative arch out of standard brick with the keystone being a piece of granite with an L engraved in it. Something like this photo.

Now we know you were a Laverne and Shirley fan back in the 70's....

[K79]

Re: K79 Oven Build

Ok all my CF blanket is on and I'm ready to start curing. I'm using 2: 700 Watt Halogen lamps for my first few curings. I tried it for 15 minutes tonight just so I could see light from the inside of my oven. I'll start them up for longer tomorrow. In 15 minutes I had my floor at 85 F and my walls towards the top of my oven at 125F. I wonder how hot these lamps will take me??? I'm using a MT6 laser thermometer.

[fabby]

Re: K79 Oven Build

I am no expert, but I had some really low and long fires for the first three or four curings. Probably in the 3-5 h range. I did let the first fires die out several times so that the temp would not get to high. I was using a grill thermometer to monitor the temp, as I did not have my IR laser thermometer at the time. By my fourth fire, temp was approaching 400f.

My overall advise, take you time, go low and slow. Don't rush. From all the experts on this great forum, I followed there advise and I have yet to see any cracks in my 42". (knock on wood). The only other note, I had to wait at least an additional two weeks after I finished the dome to start any fires as I was out of town. This probably had something to do with drying things out as well because the daytime temps were above 75F as well. The longer your mortar cures, the stronger.

[GIANLUCA]

Re: K79 Oven Build

That's cool!! I like it

[K79]

Re: K79 Oven Build

Ok so I've been reading the past few days on the curing fires. I'm going to put in a few 500 watt halogen lamps. My question is... and I find all kinds of answers on here is... do I hold my first fire and those following once i hit my desired temp for 6 or so hours (some say the first two fires hold for 12 hours or more) or do I drop down to ambient temp once I hit my high for the day?