first run casting and i've got some questions

[jondavis0904]

After 150 bullets any oil on the mold is long gone. Preheat the mould well by dipping the end, not just a corner, of it into the lead and counting to 150. At that point it is probably too hot but is is easier to cool down a mould than heat it up. If the sprue is taking less than 8 seconds to cool the old is too cold for those bullets, at least until you get a good casting rhythm going. Most guys say you have to clean the heck out of a LEE mould, I say just burn that oil off and get a coating going on the mold, kinda the easy way to smoke a mould. Same for Mihec, noe and BRP moulds. You may sacrifice the first few casts but saves a lot of time cleaning. Sacrilege, I know, but I cast 5-10,000 bullets a week so I will stick with what works for me.

The sprue was cooling almost as soon as I got done pouring into the mold. Sounds like my problem is a very easy fix with my hotplate/dipping the mould.

[MikeS]

Yes, the problem you're having is the mould is too cold. Your pot temp is right (assuming your PID is correct), and your cleaning sounds like you got the oil out of it. You might want to try cleaning it again, as it can't hurt. I also use a PID on my Lee pot, and I keep it set to 350C (which converts to 662F) for most of my casting, I generally don't even cast hotter when casting hollow point boolits, something many people here think you need to do.

So, clean the mould again, and use your hotplate to preheat the mould. I usually put my mould on the hotplate and turn on both the hotplate, and Lee pot at the same time, and by the time the lead is ready to cast, so is the mould. One thing you'll need to do is check your hotplate. My first hotplate ( cheap open coil bought at Walgreens for $12.00) needed to be on HI to heat the mould, but my next hotplate (cheap one that has a solid top, bought on Amazon for under $20.00) needs to be on the MED setting to keep the mould at the proper casting temp. Another thing I do is I keep the hotplate on the whole time I'm casting, so if I take a break I put the mould back on the hotplate, which is the reason for making sure the setting is right, I can take a 5 minute break from casting, and the mould will still be at the right temp for casting.

Another thing, because you're using an aluminum mould you'll need to cast as fast as you safely can, aluminum moulds loose their heat very fast! I find that when I'm casting with an aluminum mould I need to cast fairly fast, when I'm casting with a brass mould I can cast at a slower pace without a problem, in fact the slower pace keeps the mould at the proper temp without the need to cool the mould with a wet rag as many folks do. I try to regulate the temp of the mould while casting by varying my pace so I don't get the mould too hot to the point where I would need to cool it off.

[jondavis0904]

the hotplate I have is also one of the open coil cheapos from walgreens.

[Case Stuffer]

Good news is that casting mistakes are an easy do over and once you learn thru experience it will likely say with you for many years.

http://castboolits.gunloads.com/show...ding-a-bicycle

Like Springfield I never bother to clean my molds ,well I did have to clean a few that had developed a bit of rust from 30 years of storage. I agree wth others that your mold was to cold but can not understand how after that much casting.

I use a 35 year old RCBS Pro Melt, set the dial to 750 , place mold(s) on top ,remove molds to flux then start casting. I was getting good boolits on third cast of the day in a 60 F shop with doors and windows open and a light breeze blowing outside but no real air movement cooling the mold(s). I had to slow down my casting rate after 15 minutes or so as the sprue was taking to long to cool.


I have long looked at casting as more of n art than a science. My lead thermometer is still missing in action snce mymove six years ago however my pot dial was fairly accuarte last time checked years ago.

[metho]

Make sure you are pouring fast enough. If you pour too slow or are stopping during the pouring process it will cause wrinkles.

[David2011]

The sprue was cooling almost as soon as I got done pouring into the mold. Sounds like my problem is a very easy fix with my hotplate/dipping the mould.

You can get your mold hot, even too hot with the hot plate but you can't keep it hot with the hot plate. I use the same Walgreen's coil type hot plate and it works just fine. The mold temp is controlled by the pace at which you cast. It's less important if your melt is at 675 degrees or 725 degrees. If you cast too slowly, the mold won't be hot enough. If you cast too fast, it will be too hot. It's more of a feel thing than a measurable thing. My pace usually needs to be 3 to 3.5 pours per minute- a new batch every 17 to 20 seconds. It may not sound like much but seventeen seconds per pour is a LOT faster than 20 second intervals and 15 seconds per pour is flat out humpin' it.

David