$20 toast oven left puddles (old oven)

[corey012778]

I remember when these topic started. Jumped right into pcing. Bought a cheap Walmart oven, used the same method. Set my timer for 25 mins (know or knew the ovens habits) set to my phone, check with 8mins left 1/4 of them where melted (just nubs) and 4 or 5 where starting to do that. Maybe 1000s of boolets just in these one oven alone. Never had that happen.

Plus side the coating bonded well

[bangerjim]

"Ya gets what ya pays for!"

Don't buy cheap ovens. I went thru 4 of them B4 investing over $120 in a new Oster convection digital controlled/display BIG cavity oven. Holds temps to ±1°F and can bake upwards of 500 boolits at a time.

You are always hearing from people on here buying $5 ovens and the get great success. Good for them. I wasted almost $80 on junk ovens before seeing the light.

The sagging lumps of Pb you are getting are due to a VERY poor temperature profile in your cheap oven. A pizza does not care if the temp is 400 in the middle and 500 at the edges. Your boolits do! The thermal mass of the pizza averages it out.

The oven is the most critical & valuable part of your PC hobby. Spend some money and get a good one the 1st time. Don't waste time & money putting a PID on a cheap over either. It needs to be a convection style also.

Good luck and don't go cheap. It's not worth the hassle and mental stress.

Been doing this since 2013 and worked with a bunch of fine folks on here to develop the PC techniques. We have learned a lot since then and one of those things is the accuracy of the bake oven.

banger :guntootsmiley:

[Chaparral66]

My first attempts as PCing with a Wally World toaster oven produced pudgy boolits. They went back into the melting pot. By using a thermocouple and digital temp meter I tweaked the temps into the correct range. Now using the same oven for Hi-Tech, but noticing the center is hotter than the edges. Gonna hafta get a convection oven. Hmmm... thought I saw one up in my attic.

[HATCH]

you do know that you can put a PID controller on that oven

[corey012778]

I got a better oven in storage, guess I need dig it out. I do know you can put a pid on one. In fact, built and ready that was for a metal furnace never built furnace it self.

[kevin c]

If the temp inside the oven is correct for setting the coating, what might help even out heating the boolits is to rotate the tray 180° half way through the bake.

This is fine for shake and bake methods, but harder if the boolits need to be upright and separate throughout the bake. And if the problem is a tray with a hot center but cool edges, rotating won’t help. Another potential problem with this is heat loss from opening the oven. Having a thermal mass in the oven can help with that.

Even a high end convection oven can have hot or cold areas, as I found by moving a k probe inside a boolit around my Breville. I always turn the tray, usually shaking it at the same time.

[popper]

294054
My method of cooking. Fill up the black holder, lift to remove. Turn on hot plate (max) and cover with the white dish on left. Stop after 20 min if airdrop or 1 hr if WD. Don't need the black holder for pistol stuff. PID controlled oven getting dusty on the shelf.

[Chaparral66]

PID is next for pot and oven. I think I have one in my room of saved parts. Some might call me a hoarder or pack rat. I like to think of my self as a visionary for used parts.

[corey012778]

Never know when you need something

[William Yanda]

All
If variation in temperature between the center and the edges is the problem, would a large mass, steel or ceramic help in alleviating the problem? It would take longer to get up to temp, but it seems to me that it would tend to even out the temperature fluctuations.

[Beagle333]

You need to use a PID on a cheap oven to get best results.

But better yet, as Bangerjim says..... buy a nice oven and enjoy the hobby more.

Happy coating!

[Loudy13]

I second BangerJim buy a decent one ( I have the oster also) and then put a oven thermometer in it, I check mine after throwing a fresh pan of boolits in after 5 minutes to make sure it is tracking then check again at 15 to make sure it isn't getting to hot. I also put the next pan in line on top of the oven to give it a little pre heat.

[GregLaROCHE]

My non convection $25 oven from Ebay has been working fine for me for years. I guess I just got lucky.

[bangerjim]

All
If variation in temperature between the center and the edges is the problem, would a large mass, steel or ceramic help in alleviating the problem? It would take longer to get up to temp, but it seems to me that it would tend to even out the temperature fluctuations.

A thermal mass would help. Some on here have tried that. But your pre-heat time would be greatly increased. You would have to do some playing around with a survey of the internal temps in the 4 corners and middle to determine the preheat time needed. Use a GOOD accurate oven thermometer!

Best bet is a good high-end digital convection oven. The standard bi-metal temp sensors in cheap ovens are not worth a darned.

Pizzas don't care. Boolits DO!

[mto7464]

bought a good used convection oven on facebook market place. It was dirty and gross, the girl knew me and said I would not want it, not in the kitchen but for PC its great.

[corey012778]

I have to get to my storage unit I have a nicer one in there. Could retired my old air fryer and get a nice double door version for the kitchen. Sorry random thought

[Cosmic_Charlie]

I use a $1,000 LG electric range. Works like a charm. 400 deg. is not enough to cause issues with the lead and the polyester powder is benign.

[Charlie Horse]

My first attempts as PCing with a Wally World toaster oven produced pudgy boolits. They went back into the melting pot. By using a thermocouple and digital temp meter I tweaked the temps into the correct range. Now using the same oven for Hi-Tech, but noticing the center is hotter than the edges. Gonna hafta get a convection oven. Hmmm... thought I saw one up in my attic.

The problem is uneven heat distribution. The fix is easy. You have to make some baffles to keep the heating elements from radiating directly on the bullets.

My cheapo oven has two wire racks. It came with a tray. I got myself two, thin metal plates a little smaller than the racks.

The tray that came with the oven goes on the bottom rack. A couple 1/4 steel rods go on the tray. One of my metal plates goes on top of the rods. This set-up elevates the bullets from the base of the tray. The tray gets real hot because it is close to the bottom heating element. When I put bullets directly on the tray some melted. The rods and the plate keep the bullets up off the tray.
I put a sheet of parchment paper on the metal tray, then stand the bullets on it.

The other metal plate goes on the top oven rack. That plate keeps the top heating element from radiating directly down on the bullets and melting them. Even a doubled-up piece of heavy-duty foil would work on top.

Easy-peasy.

[brassrat]

My thrift store oven does fine. I only do pistol boolets, all standing up. Ten good minutes right on the oven tray seems to work. The boolets will need to be snapped off the tray but leave a perfect covering with no fins. Never have taken a hammer to any but have had no problems except for last batch which didnt cover too well, I think the powder got expired after the ten years or so.

[JimB..]

For the record, temp control is important for pizza.

I felt like a rube buying an oster oven from wallmart, just couldn’t find one at the thrift store, but it works.

[rockshooter]

When I had this issue I discovered that when the oven pre-heat cycle is on the top broiler turns on, which gets things too hot. Now I just wait until the broiler burner goes off then stick the bullets (just dumped on a wire tray) in and let it cook for 15-16 minutes. This is with a $8.70 thrift-store toaster oven that has worked fine for years now.
Loren

[justindad]

The problem with the cheap oven is that a heating element is right over and under the bullets, and the radiant heat of these elements causes your bullets to get way hotter than the temperature dial set point. The fix is to make a tin foil hood to go between the upper heating element and your bullets. The pan you set your bullets on may be good enough to prevent radiant heat from the lower element, or you may want to place a second pan in there as a heat shield.
*
Like rock shooter said, preheating the oven also keeps down the temperature spikes.