new caster, new mold = problems

[lockinload]

As the title says, I have a new Lee, 2 cavity 10mm SWC 147 gr. The cavity closest to
the handles will not fill to the top of the mold. The lead comes out the top but when
I open the handle and knock the slag off the boolit has not filled the cavity and I have rounded corners.
The other cavity works fine. Any ideas? BTW, I did clean my molds and applied a black spray on release.

On a positive note, my 6 cavity 9mm works pretty sweet.

[Walter Laich]

sounds like the mold, or that end of it, is still too cold. Also be sure you are pouring directly into the sprue opening and not hitting the side of the hole.
I would keep working with it and it should finally warm enough to allow you to fill the mold.
Flow rate is something also to check. Not too fast or slow--like Goldilocks

[mikeym1a]

I have the same problem with my Lee molds until I get them up to operating temperature. Usually the first 25-30 casts go straight back into the pot. I think the problem is that the sprue plate is too cool, and the lead is cooling and plugging the hole before it is full. I try and pre-heat my mold. I put the burner on the stove on medium, and put the mold on the burner, sprue plate down, to get it warm. Even after a long wait, and the lead it fully melted, it still will take a dozen or more casts to get things going right. That is my experience, don't know if any others have the same problem. Be patient. It will get there. mikey

[JonB_in_Glencoe]

It could be a venting problem.
sometimes a "spray on" release agent can block the venting.

I have never found the need for any type of release agent [including smoke/soot] on Lee's molds...YMMV

[Bzcraig]

I'm thinking if one hole is filling fine it's not a cool mold. As mentioned check flow rate, venting,pouring directly in the hole and make sure you haven't over tightened your sprue plate screw. To determine that loosen the screw so the plate swings free and try a few. If your using a Lee bottom pour you could also rest the sprue plate tight to the nozzle and pour. I found every time I had that problem I was pouring too fast and once flow was adjusted right all was well.

[lockinload]

Thanks gentleman, where is this vent hole you speak of? I will try heating the spruce plate better.

[HeavyMetal]

Ya each mold can be a story unto itself, LOL!

I'd clean it again, removing the release agent and consider putting a very slight bevel on the top portion of the block under the sprue plate.

I have no picture but if you do a search here you can see several examples posted, and I do mean a very slight bevel!

The purpose of said bevel is to act as one more vent line allowing air to escape as your filling the cavity.

If this was my mold here's how I would proceed:

1 clean real good

2 heat up the pot with the mold on top to get hot

3 dip corner of mold into alloy, mold closed sprue plate shut empty, until alloy does not stick to mold

4 then instant dip sprue plate, the area that you supposed to "hit" to open mold until alloy does not stick to it

5 cast boolits smoothly waiting for the sprue to completely solidifiy before opening, the mold will cool down after the above treatment and you will need to dip the plate or mold cornwer as needed to cast good boolits.

If at this point you still can't get both cavities to fill out properly then bevel the the top edge of the mold block and try again.

[JonB_in_Glencoe]

Thanks gentleman, where is this vent hole you speak of? I will try heating the spruce plate better.
No vent hole.
the air in the cavity needs to escape...Most molds have engraved 'lines' in the moldface as seen below. Venting also happens between the sprue plate and the mold top. The New Lee molds have a new design for venting machined into the mold faces...I suspect your release compound has stifled that.

http://i640.photobucket.com/albums/uu127/JonB_in_Glencoe/moldface.jpg (http://s640.photobucket.com/user/JonB_in_Glencoe/media/moldface.jpg.html)