Heating Molds on a hot plate

[Jevyod]

I have just a quick question. I just picked up a new hot plate to preheat my molds. It is a solid top 900 watt unit. I have aluminum molds. If I recall correctly, aluminum molds can warp from too high heat. I don't have a thermometer to read the heat of the hot plate. So what is the best way to make sure my Accurate mold does not get overheated? I read somewhere of putting lead on the plate and using that as an indicator that the plate does not get too hot. So is that a good idea? As long as the lead doesn't melt, the plate is not too hot?

[William Yanda]

You got it. And the hot lead, when added to your pot will not chill the alloy already there. I'll bet you are the kind of guy who would notice the setting where lead melted and take care never to exceed that again, too. My hotplates are the coil type. I believe the solid kind may have a thermal limiter like my wife's cook top. I have no idea what they are set at-they will melt pewter, but don't tell her I know that.
Bill

[TCFAN]

I run my hot plate on the hi setting. Don't know what the wattage is.I use a old 10 inch table saw blade to spread out the heat. I have never warped a aluminum mold.My aluminum molds are NOE, Accurate and Lee.I keep a surface thermometer on the top of the blade and it never gets over 350 deg. or so..................Terry

[Jevyod]

I run my hot plate on the hi setting. Don't know what the wattage is.I use a old 10 inch table saw blade to spread out the heat. I have never warped a aluminum mold.My aluminum molds are NOE, Accurate and Lee.I keep a surface thermometer on the top of the blade and it never gets over 350 deg. or so..................Terry

So just a cheap grill surface thermometer will work for this?! Such a simple answer! Thanks

[LenH]

I have one of the flat top hot plates the wife got me at Wally World. I didn't know how hot it was getting and got my mold hot and was casting to beat the band.
I put several ingots on the surface to warm while casting. about 10 minutes later I had a big stinking mess. He ingots had melted and run all over the bench. I prolly
need one of those surface thermometers. But after that mess up I don't heat ingots any more.

[Retumbo]

I mounted one of these up side down on ceramic stand-offs. IIRC mine is rated at about 250watt

[bangerjim]

Once you find out where your dial is at, mark it! My flat-top is a lab unit at 1500 watts.

Once I knew the temp setting, I just use that every time. I hope yours has a setting dial!!!!

Putting lead ingots on your hotplate also saves time when feeding your casting pot! Bring them up to almost melting and they dispear fast when you put them in the pot. As always, use extreme catuion when picking them up!!!!!!!!

I have never warped any of my 35 or so Al molds.

banger-j

[white eagle]

I also use a clam type hot plate for my molds as well
just plug your hot plate and lead furnace in at the same time when the alloy is melted the mold should be at temp

[bigarm]

I use a hot plate I got from Wal-Mart. It is not a coil type but the top has little ridges on it. I got some lead splatter on it and don't know how to clean it off. Any ideas? For the moment I put a saw blade on top because the little bit of lead splatter got on the bottom of my mould. How do I clean that off?

[bangerjim]

I use a hot plate I got from Wal-Mart. It is not a coil type but the top has little ridges on it. I got some lead splatter on it and don't know how to clean it off. Any ideas? For the moment I put a saw blade on top because the little bit of lead splatter got on the bottom of my mould. How do I clean that off?

Set your plate on high until the lead spatter melts and then wipe it off quickly with a rag or leather glove. Same with mold.

[500MAG]

I use an electric junction box with a metal cover on it with the end cut out as sort of a mould oven. I have it on top of a hot plate. It will hold 2 moulds with the handles sticking out and I place some lead ingots on top of it to preheat them.

[Shooter6br]

I use a hot plate and a homemade box(electric box) on top.I use a Harbor Freight IR themometer to check temp

[GrayTech]

I mounted one of these up side down on ceramic stand-offs. IIRC mine is rated at about 250watt

What the check is that? Looks like a useful idea.

[A pause for the COZ]

I just keep mine set at 50% power.
Been working great. Put the molds on when I turn on the pot. Both are ready at the same time.

[Land Owner]

I use a Mr. Coffee with the resevoir cut off. I don't know what its temp is, not nearly the temp of the pot, and until I read this thread, had not thought to use a piece of lead as a test strip nor to pre-heat the lead before putting in the pot...both substantially good ideas. I learn something here every day.

[Bullwolf]

I put an old skill saw blade on top of an electric element hotplate.



I keep ingots on the hot plate as well, to pre-warm them. Linotype ingots go slushy sooner (at a lower temp) than WW or pure lead ingots on an overly warm hotplate - ask me how I know this.

Despite over warming moulds to the point of melting ingots on the skill saw blade next to them, I have yet to warp an aluminum or steel mould using a hot plate. I also use the hot plate to heat cycle brand new moulds a few times, before casting with them.

I use a coffee can lid (mold oven) on top of the hot plate if it's cold, or very windy outside



When I add the lid, it often requires that I turn down the heat some. (or else ingots melt) The lid really helps contain the heat on a windy day.



- Bullwolf

[tryNto]

I use an electric junction box with a metal cover on it with the end cut out as sort of a mould oven. I have it on top of a hot plate. It will hold 2 moulds with the handles sticking out and I place some lead ingots on top of it to preheat them.

I will be making up one of these to go with my Hot Plate.

[Land Owner]

Bullwolf...that is a nifty idea! That makes three ideas I have learned here today. The Medical Community says your brain gets a fold for each when new ideas are experienced. My brain is warping here so fast that I better stop reading before my face implodes.

[Sticky]

What the check is that? Looks like a useful idea.

That is a strip heater... meant to be mounted to a flat plate, so if you mount it under a piece of aluminum plate, you have a 'hot plate'... lol

[krallstar]

I use an old electric griddle to heat mine. I put lead ingots on it and my molds. Turned all the way up hours later if i drop an ingot in, the temp does drop some. Still takes maybe 5 or 6 casts to start dropping right.