Hot plate - PID - yessir!

[Fishman]

I picked up a Sylvania hotplate at Walgreens for $12.99 with a $3 mail in rebate earlier this week. It is an open coil design and gets plenty hot. I had never preheated my moulds on a hot plate before and now I am sold. No more casting like mad for ten minutes to get the mould up to temp. No more hard sprues to cut. It's great.

It also allows me to cast more effectively with my little ten lb lee pot. I can preheat the ingots on the hot plate (careful!). I did get one of Frozone's PID controllers and it shows just how much the Lee pot temp drops when adding a preheated one lb ingot (about 75-100 degrees).

This weekend I'm going to hook up my Lyman 10 lb dipper pot as a reservoir to melt sprues and add ingots and I think I will get very consistent results. I'll transfer molten alloy to the lee pot and just keep trucken'. I'll be running it and the hot plate on a separate circuit from my main pot.

I love the PID, but from a value standpoint, the hot plate was the buy. Every caster would do well to get one.

[Griz44mag]

A hot plate is the way to go. I started using one many years ago. Two burner, one has a cast iron pot on low to keep ingots prewarmed, the other burner is for the mold for pre-heat and hold heat while I break or do other tasks. I have gone through a few of them, almost all from Wally's finest.

[frankenfab]

If you put a shroud over your hot plate, you can heat the mold and ingots at the same time, plus there is no worry or adjusmet of temperature for warming ingots. The mold will also heat faster.

I also have a 3/4" disc on top of my hot plate. I was skeptical that it might take alot londer to heat with the disc on top, but it does not.

I didn't come up with the coffee can shroud idea, I got it from this site.

http://castboolits.gunloads.com/imagehosting/12827501ee4978fc5f.jpg

[Griz44mag]

I bought a 2 burner, so there is no need to double stack anything or share burner time....
The mold is always ready by the time the pot has the lead ready. The lead pre-heat gets set at #2 setting, the mold at #4, works perfectly.

[popper]

PID works great for the hot plate also.

[Fishman]

I didn't get to hook up the dipper pot as well this weekend. What I did instead was cast .350 balls from a 2 cavity while my melt warmed up from adding alloy. Since they are going to be used for buckshot, uniformity wasn't necessary. That said, they still turned out better than most boolits i have cast.

With four moulds on the hot plate, I could just change to a different one when bored with casting a particular boolit. I also cast some lee slugs which came out perfect. Never could get fill out before.

For the price/benefit, the hot plate is a no-brainer.

[bootsnthejeep]

You guys are killing me. MORE stuff to get and build! I already caved on the PID! Preheating is next. Especially for my NOE RG4s, doing the lead dunk with those pin slides in the bottom is touch and go, I've gotten good results by just casting fast, but I can see this mould oven is probably the way to go.

Drat. There's a Walgreens on the way to the bank on payday. I'll just stop in and get it...

But a legitimate question: Does anyone notice any difference between the open coil and the closed coil hotplates? For some reason I see mostly open coil ones around here. I know I can just put a piece of steel plate on top of it, but the sealed ones seem better for some reason. Just some dumb visual thing of mine, I'm sure.

[H.Callahan]

I have the opposite problem. I am finding only the closed top ones. IMO, the coil units heat better than the closed units. ...and older units that are several years old seem to be better than new ones. The new ones all seem to have "thermal protection", which causes the unit to shut off when it gets hot. Frankly, I thought that was the point of a hot plate, but I guess the public nannies know better than I.

[Mal Paso]

I just picked up that open coil Hot Plate at Walgreens. I have a chunk of copper to go across the top. Just need to find a coffee can that's Not Plastic. [smilie=l:

[Beagle333]

Just need to find a coffee can that's Not Plastic.
I need to get me one of them PIDs. That'd be a handy unit!
WalMart, Sam's, Kroger, etc.... all sell gallon cans of green beans (and other veggies) in metal cans. I go through lots of green beans! :mrgreen:

(the only metal coffee cans around here are the gourmet brands, and they aren't a gallon size :???:)

[Mal Paso]

I just measured and it looks like a 1 Gallon Paint Can would be perfect. I may just blow $1.25 on a new one next time I'm in town.

[Ken73]

So if you've got the coffee can setup;

http://castboolits.gunloads.com/imagehosting/12827501ee4978fc5f.jpg

where is the best place to put a thermocouple for the PID unit?

I've got my hotplate and my metal coffee can ready to go!

[frankenfab]

I plan on drilling a hole for the probe in the edge of my 3/4" disc, as well as other holes to put single hollow point pins with handles in to preheat them. Haven't got there yet.

Other wise (without the disc), I would say just get a piece of 3/4" square or other thick piece of metal and drill it for the probe. Maybe put it in the back and punch a hole in the can with a nail to stick the probe through.

[Idaho Sharpshooter]

We live a sheltered life out here in the territory. What is PID?

Rich
Sua Sponte

[just.don]

http://en.wikipedia.org/wiki/PID_controller

[Ken73]

Rich, it's a fancy digital thermostat that compensates for the heating/cooling cycles after a learning period to keep whatever it's controlling at a near-consistent temp. I discovered it on a thread here myself so don't feel bad! Those that have them though, swear by them for getting consistent boolits.

[edler7]

I got one of the Walgreens Sylvania hot plates. I put a 3/8 inch piece of aluminum on the burner to better distribute the heat. With the hotplate set on medium, it will melt a 1 pound ingot of WW if I leave it too long (I found that out the hard way).

Great for getting that Miha brass mold up to temp !

[Frozone]

3/8" steel plate, weld box tube to it an stack em 3 wide, 2 high. Close off one end of the tubes with a second piece of plate. weld pipe to tghe side for HP pin holders.
And you have a 6 mold oven that will also heat ingots on top.

[Fishman]

So if you've got the coffee can setup;

http://castboolits.gunloads.com/imagehosting/12827501ee4978fc5f.jpg

where is the best place to put a thermocouple for the PID unit?

I've got my hotplate and my metal coffee can ready to go!

To be clear, I have bit a single PID, so mine controls my casting pot temp. I personally wouldn't get one just to run the preheat oven as I think it would be overkill. I've found my moulds preheat just fine when the plate is turned just past medium, no can required. Of course, if you want to, that's just fine :)

[Ken73]

To be clear, I have bit a single PID, so mine controls my casting pot temp. I personally wouldn't get one just to run the preheat oven as I think it would be overkill. I've found my moulds preheat just fine when the plate is turned just past medium, no can required. Of course, if you want to, that's just fine :)

OH! I mistakenly thought you put a PID on your hot plate. That makes things a bit easier (and cheaper!) then. :oops: 8-)

I do have a thermocouple/digital thermometer setup, thinking about drilling my molds for probes so I can see what temp they're at at least.

[sthwestvictoria]

I am a new convert to the hot plate as well. I was lucky to find one for $AUD5 at a garage sale (yard sale for our American cousins).

It really makes life easier - preheating molds, ladle. It is also used for melting the pan lube, thus avoiding the open flame of the camp stove.

[Griz44mag]

(yard sale for our American cousins)
LOL, we're not so different here on the other side of the planet.
I can't speak for the whole country, but here in Texas it's usually called a garage sale too!
And a yard sale, and an estate sale, and a junk sale!
.
I have never had any issues getting molds up to temp without a "hood". And once I start casting, I don't let up until I'm ready to quit. I got a 2 burner one at Wally World, so I stack one up with 1# ingots on setting #2 for pre-heat, and molds on the other at setting #4.5. By the time the pot is melted and up to temp, the mold(s) are also ready. The burners are large, solid and coated with teflon or something like it and not the wired coil type, so I don't need a plate or a sawblade on them, they are already a nice smooth surface that heats very evenly.

[William Yanda]

I've got to get in on this conversation. I found a two burner hot plate, Sears, no less, at a yard sale for a buck ( $1 American). The hard part was that SWMBO was along and said: "I can understand the chisel, but I got you a hotplate for casting for your birthday!" But at least she didn't make me walk home.