New problem with a new mould

[Muskrat Mike]

I got a Lee 2 cavity mould awhile back for the 35 rem and finally got to try it today. I'm casting #2 made by adding 95/5 solder to WW and I got beautiful bullets dropping right out except the cavity closest to the handle hinge the base is not sharp and square like the base of the the front cavity. I ran the temperature up to 850 and back to 700 no difference. I loosened the spue plate a little no difference. I of course made sure I had a large puddle on the spue also, no difference. I finally gave up and finished my casting session using only the front cavity. I lubed the mould and spue plate with Bull Plate like I always do . Could it be a venting problem to that cavity? What am I doing wrong?:-(

[geargnasher]

Search "leementing" here, many good tips. Sounds like a venting issure to me, but possibly a heat issue. If the rear cavity is casting frosty boolits with poorly filled out bases, then I would look at venting issues, (bevel the top edge of the blocks and LIGHTLY trace the vent lines with a scribe/razor blade. If the bases are shiny, then the mould/sprueplate is too cool and you need to cast faster/preheat the mould on a hotplate between pours. It also helps a bunch with two-banger aluminum moulds to alternate which cavity you fill each pour, keeps the heat evened out.

I have a love/hate relationship with Lee moulds. I have some that are an absolute joy to work with, others that make me so mad I could chew nails. Over the years I've thrown a couple in the trash and currently have three I won't cast with anymore because it just ruins my whole day.

Hope your luck is better than mine!

Gear

[runfiverun]

or pour that hole first for a while then alternate.
i have to alternate directions on some of my 4 cav's to keep even heat in the mold.
also you might just be openng the mold a bit too soon for that cavity but the alterning holes usually works.

[44man]

I just worked on one that was flashing the bases. I had to mill .002" off the top of the mold because indicating it showed opposite corners .002" higher. I also had to mill the bottom of the sprue plate.
Even after that I had to give the mold top a slight lap.
Kind of hard to put a gas check on when the bases look like a mushroom.

[docone31]

If you soak your mold in mineral spirits for a couple of days, You might see a difference in casting.
However, if it is still balky, cast through a nut, I prefer 1/4-20, on both cavities. Take those castings and one at a time, smear fine valve lapping compound on them. One at a time, replace in the cavities, and real slowly, close the mold on the casting while turning.
Once this has been done, alternate the models in the cavities. This evens out the the molds.
It does though sound like an heat issue.
With balky molds, I set the mold in the pot. I try to get a sprue to not freeze fast.
Once I get a sprue that takes a long time to freeze, I slow down the casting untill I get good fillout, and freeze time.
It does sound like heat as your description of the hole close to you not filling out.
Soak it, heat it, polish it, cast it.

[EMC45]

Have had that happen with my molds (Lee) and just switched up front to back and vice versa. It helped.

[StarMetal]

Why not put Kroil oil in the cavities. Some here really believe that works. I don't.

Runfiverun gave some good advice. I found a difference in how a well a cavity fills by reversing the filling order, tilting the mould different, trying the molten stream straight into the sprue hole, adjusting the size of the stream flow, etc.. I always go with the theory of a very very clean mould. Meaning free of oil or lube...whatever. Rarely on some occasions I have suet smoked cavities...not often thought.

Joe

[mooman76]

I've run into that problem recently a couple times. I believe it is a venting problem as I cured it by loosening the sprue plate. One I actually had to loosen it to where I thought it was too loose but it did put out good bullets after that. I even tired retightening it later on to see if it was a fluke and I was right back to before so I loosened it again.

[shotman]

star has learned send it to me I will send you back good boolits. Kroil works. dont believe the old farts that do the same BS every day. They didnt want computers and cell Phones. get you some it will make your day rick

[Muskrat Mike]

Thanks everybody for all the responses! I'm going to the the hunting camp for a long weekend and getting a knee operated on next tuesday so it will be a while until I can try the mould again but I'll let you all know what works if I find the ansewer.:Fire: