No Venting ? New Lee 2 Cav. 452-160

[Scotstr]

I just got a new Lee 2 cavity 452-160-RF the other day. Cleaned it with brake parts cleaner, then Comet and a tooth brush. Preheated. Lee pro 4-20 pot with cleaned WW metal with a little extra 50-50 solder. Started casting when the Lyman thermometer said 850. Bullets coming out frosty , but the middle band of the bullet is always rounded, mold not filling out good.
Looking at the mold faces, there are no vent lines whatsoever. Did I just get a bum mold ? I have 20 + Lee molds. This is the first 2 cav. I have purchased in a long time. Most of my Lee molds are 6 holers.
What kind of venting does Lee use on the new style 2 cavity molds ?

[John Boy]

Started casting when the Lyman thermometer said 850. Bullets coming out frosty , but the middle band of the bullet is always rounded, mold not filling out good.
Looking at the mold faces, there are no vent lines whatsoever.You best back that casting temperature down to 700 -730. You'll find that you will have perfect bullets when the pot temperature & mold frosts the sprue puddle at 5 seconds with a 5 second pour

Don't know if no vent line is something new with Lee ... but I cast perfect bullets with old Ideal molds that have no vent lines

[dkf]

There is a strip running down the center of the mold which is cut maybe .001" deeper than at the top and bottom edges of the mold. This machined section vents the mold. My one Lee was not venting as well as I like so I put a tiny (and I mean tiny) chamfer at the top of the mold halves.

I noticed with Lee molds it takes a bit to get all the oils cooked out. Either clean and heat cycle the mold on the hot plate a couple times or boil in water for a little while.

[Scotstr]

Thanks for the responses, Gents. I did notice the new style vent "band" across the faces of the mold blocks. I called Lee and spoke with a guy in the Tech. dept. He made the usual recommendations, smoke the mold, clean the mold again, turn up the pot temp, etc. I am going to try boiling it, cleaning it again, and some time on the hot plate. If that doesn't work I will do the chamfer on the top seam.
Thanks again.

[JonB_in_Glencoe]

I chamfer on the top seam on all my lee molds, along with deburring the sprue plate.

[selmerfan]

One should only smoke pork, beef, venison, poultry, cheese, oysters, fish, and the occasional cigar. NEVER a boolt mold...it's not a "fix" for anything.

[MtGun44]

+1 on no smoke.

Bill

[GaryN]

On a new Lee mold I would bring it up to temp. and then let it cool off several times. This is how you heat cycle the mold. It leaves a minute bit of oxidation in the mold that helps it release when you pour in the lead.

[burrkiss]

I gotta give a +1 for smoking a mold. I started out just cleaning my lee's and was wacking every cast with a wooden handle. I recleaned with break cleaner and smoked twice and now I dont even know where that wacker is. Perfect drops 98% every time (sometimes I gotta shake a tad)

[DLCTEX]

I never smoke a mould anymore. If the mould won't drop boolits, fix the problem.

[Old Caster]

That is a too high temp problem coincided with going too fast.