Warming A Bullet Mold On A Hotplate

[ArrowJ]

I am looking for a little clarification concerning hotplates. I know some guys are warming their molds this way, but noticed that several (all?) are using an aluminum plate or other contrivance on top of the hotplate. Is this necessary regardless of the type of burner i.e. coil vs cast iron? The hotplate I purchased has two burners. The larger one is 1000 watts and the smaller 700 watts. They have cast iron burners with concentric circles cast into them. I plan to melt with the larger (assuming it is hot enough) and warm the mold with the smaller. Is it imperative that I place something between the burner and the mold?

[mongoose33]

Do you have to use a plate? No.

But people use that out of concern for warping a mold w/ the temperature differences between the coils and the space between them.

I use a circular saw blade; if you don't have a dull one around you can donate to the effort, you can find them at the home store for maybe $2.

[JSnover]

I made a lid for my pot out of sheet metal, that's where I park the mold to warm it. I'd be a little leery of having aluminum on top of the coils. If it's thin it might melt.

[dragon813gt]

Open coil, use something like a saw blade to evenly distribute the heat. Solid top, just place the mold on it and cast away.

[Tailhunter]

I have one with the solid "cast iron" tops, it works like a charm. I wouldn't cast without one.

[SSGOldfart]

The bottom out of a old coffee can works great,I took a second can and cut two holes for the mold handles and parked it on top of that bottom plate made out of the first old coffee can,this traps the heat very well,
my hot plate is a 700watt eBay special,under$20 bucks

[bangerjim]

You do not just "WARM" the mold! You heat it to FULL CASTING TEMP!. That way you will get perfect drops from #1.

I have never used an open coil plate, but those that do use some kind of plate between the coil and mold.

bangerjim

[ArrowJ]

Thanks banger jim! I have not actually cast any bullets yet so I am still somewhat fuzzy on all of the technique and equipment use. These are "solid" plates but have ridges in them so I think I put something on top before I heat my mold.

[Epd230]

I started using mine without a plate. I also use it to preheat my ingots. Leave an ingot on the coil too long just once, and you will want a plate or pan for easier clean up.

[bangerjim]

I started using mine without a plate. I also use it to preheat my ingots. Leave an ingot on the coil too long just once, and you will want a plate or pan for easier clean up.

Pointing out the ingot pre-heating is excellent. I do it every session. Actually you can use it as a poor man's temp sensor for your molds. If the lead ingots start to get slushy on the bottoms, your are at full casting temp! I then back off the dial a touch and use it from there for molds and ingots. You do NOT want them melting thru coils, so use a flat plate. Some use an old saw blade, but I have not old ones! All my blades are high-end premium carbide blades. I would go with a 1/8" flat aluminum plate if I needed that. My unit is a flat surface lab plate and does not need anything added.

A good hotplate is just as necessary to successful modern casting as a pot, lead, and molds.

banger

[Outpost75]

I use a cheap Proctor-Silex electric hotplate from Walmart, and place a piece of ceramic tile over the coil. I use a 350-degree Tempilstik crayon on the mold blocks to calibrate temperature, depending upon the season the dial setting may change, because I cast outdoors on a screened porch for ventilation. This is not up to full casting temperature, but with my usual tin-lead alloys it only take a pour or two to get there. Also use the Tempilstik crayon to pre-heat small parts prior to touchup cold bluing.

[ReloaderFred]

When I used to hand cast, I would just place the mold on the top edge of my casting pot and let it heat up along with the alloy. By the time the alloy was ready to cast with, so was the mold.

These days most of my casting is done with a Master Caster, or Bullet Master, depending on how many bullets I need to cast. Those molds don't get preheated, but still cast just fine by about the third drop on the Master Caster, but the Bullet Master takes about half an hour running before it drops good bullets consistently.

Hope this helps.

Fred

[rsrocket1]

I used to balance the mold on the edge of the pot as it heats up. When the lead is ready, I would dip the front edge of the mold into the lead until there was no sticking of the lead to the mold and no trace of freezing of the lead in the pot when I pulled the mold out. Worked fine then, but I have since found an open coil hotplate at the Goodwill clearance store for $1.68 and a free circular saw blade. They work just as well plus you can heat up one mold as you are finishing up casting bullets in case you want to cast more than one caliber during a casting session.

Would I have been perfectly satisfied with the old system without the hotplate? Yes.
If I knew how much more convenient the $1.68 hotplate was, would I still do it? Yes.
Would I spend $20 for a hotplate for this same purpose? No

I've found better uses for the hotplate like hooking it up to my PID to blend beeswax lubes where I want to keep the double boiler temp at 150 degrees or for making 45/45/10 without starting a fire from too hot of an Alox temp. I bring out the hotplate to heat up the molds but the sawblade doesn't make much of a difference so I usually leave it off and just balance the mold on the coils.

[Boogieman]

I found a 1/2" steel plate in my junk pile , it's a bit overkill but works great, Also use it as a heatsink in my toaster oven to even out temp. swings while powder coating boolits
. '

[Starvnhuntr]

I just set my molds right on top of the melt for about 45 seconds. I know they are hot enough when the lead brushes off with a glove. I have been doing this for years with no damage to my molds.

[bangerjim]

Hotplates very in availability and $$. Mine is a $150 professional electronically controlled laboratory hotplate. Many find cheap plates for $10-15 at Walmart. Some stores do not carry them anymore. Junk stores are just too unreliable when it comes to finding something when you actually need it.

Anybody that does not have one yet.....is DEFINITELY worth $20 to buy a hotplate! You will get a lot of use out of it and even some perfect boolits 1st thing when starting.

banger

[dragon813gt]

We'll worth the money
http://i198.photobucket.com/albums/aa39/dragon813gt/TimeToMakeAmmo/E463A94C-15BA-4F4A-98FF-CB07E7074F2F-452-0000000FDC7A6FFF.jpg (http://s198.photobucket.com/user/dragon813gt/media/TimeToMakeAmmo/E463A94C-15BA-4F4A-98FF-CB07E7074F2F-452-0000000FDC7A6FFF.jpg.html)

[mongoose33]

Put something over the top of the mold to help hold heat in--it can be as simple as Dragon shows above, or you can let your OCD drive the effort like this:

153692

There are probably dozens of different mold ovens used by people on this site; just get something to help maintain heat around the mold.

[bangerjim]

Unless you are heating your mold in the arctic or in a wind tunnel, the heat transfer from the intimate contact with the flat surface of the hot plate (or saw blade) and the flat bottom of your mold will allow it to get uniformly hot. I put a 1# ingot on top of my molds while heating to maintain intimate contact between the surfaces. And the ingot gets good and hot too!

But use what ever you feel you need. I have never seen the need for "mold ovens".


I would suggest to new hotplate casters to try it first without spending a lot of time building a mold oven. Then you will know if you really need one or not.

[dragon813gt]

You live in Arizona. I'm not surprised you haven't found the need for one. Try casting in an unconditioned garage when it's 20 degrees out. You will find a need for one in short order.

[georgerkahn]

A+1 re dragon813qt's words re casting in cold environments outdoors -- here, ~17 miles south of Canada border, my "it's no longer lots of fun" outdoors casting temp is 42*F. 'Specially to better enable cool weather casting, I have an inch-thick aluminum plate on my G.E. hotplate with a wee hole bored in it for a PID thermocouple. Further, vis a wonderful suggestion on this site, an inverted small pot with a "door-way" just larger enough to pass moulds in and out resting on the hot plate.
A real secondary "plus" in using the PID-regulated "oven" is I seem to produce a significantly higher percentage "keeper" boolits using this, than without it. (I first tried this set-up with a free for the asking inverted tomato-sauce can from a local diner; further improvement attempts included the PID control, garage-sale pot, and replacement of an old saw blade with aluminum disk -- all, imho, worth the effort!)
BEST!
geo