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View Full Version : Round nose mold wrinkles.



Cosmic_Charlie
05-05-2020, 11:34 AM
I have one mold that consistently drops wrinkled boolits. And it's my only round nose mold as well. Are these problematic in respect to wrinkles? Does that round nose cause turbulence during the pour? I have poured at 800 degrees and both rushed and trickled the lead in. I have had the plate close to the spout. I have leaned the mold while pouring to help let the air out. I have cleaned the mold twice.

At least the boolits shoot well.

sundog
05-05-2020, 01:11 PM
Need more information; mould description, pour method, and alloy for starters.

FLINTNFIRE
05-05-2020, 02:06 PM
Round nose molds I have do not seem to make any wrinkles , how is your mold temp ?

Did you clean all the oils out and preheat it a few times , then heated it up before casting ?

And your lead temp is plenty hot , preheat the mold and start casting and do not stop to check till you have been running the mold for awhile , then check how they are .

GBertolet
05-05-2020, 02:09 PM
Seems like you are trying everything right. I would suspect the mold is still not hot enough. Is it aluminum or steel? Is there any oil, or other contamination in the cavities? At 800 degrees, the lead temp is certainly not the issue. For steel molds I like to preheat on a hotplate.

FLINTNFIRE types faster than I do.

bangerjim
05-05-2020, 02:18 PM
At least the boolits shoot well.

So why worry about the cosmetic look of good-shooting boolits? Too many people on here worry about dropping perfect slugs. As long as there are not massive voids in them or severe deformities and they of the nominal weight desired, load 'em and shoot 'em! I sure do!

banger

Conditor22
05-05-2020, 02:51 PM
I'm with sundog, more information needed.

Did you preheat the mold?
1 or 2 cavities?
aluminum or copper?
You said the lead was 800° was this measured temperature?
Alloy and where you got it is important
did you pour a little lead into the catch container under the spout to clear the cooler lead from the spout?
did you try pressure pouring -- bleed the spout, hold the mold up to the spout, fill the mold and lower the mold while still filing to create a puddle?

pictures would really help :).

FLINTNFIRE
05-05-2020, 03:15 PM
Seems like you are trying everything right. I would suspect the mold is still not hot enough. Is it aluminum or steel? Is there any oil, or other contamination in the cavities? At 800 degrees, the lead temp is certainly not the issue. For steel molds I like to preheat on a hotplate.

FLINTNFIRE types faster than I do.

Sorry , On a boat cruising a long pool , nothing to do was bored .

Cosmic_Charlie
05-06-2020, 06:39 AM
I'm going to have a close look at the venting pattern cut into the mold faces. I'll bet they are too shallow. It's really the only thing that could be causing the problem.

Cosmic_Charlie
05-06-2020, 12:40 PM
Need more information; mould description, pour method, and alloy for starters.

LEE 309-180R 2 cavity. Bottom pour pot. 90/5/5 95/3/2. I have 8 other molds that drop perfect boolits.

sundog
05-07-2020, 09:32 AM
If it were me, I would smoke that mold, lightly, with a wood match or butane lighter. If that does not help, it can be cleaned again.

From time time we run across a mold that, for whatever reason, defies working correctly when clean. Do not use a spray on graphite product on aluminum.

Did you lube the alignment pins, and if so, did the nose portion of the cavities get contaminated (usually by lube migration from the pins)?

I doubt that your problem is venting.

Cosmic_Charlie
05-09-2020, 05:39 AM
If it were me, I would smoke that mold, lightly, with a wood match or butane lighter. If that does not help, it can be cleaned again.

From time time we run across a mold that, for whatever reason, defies working correctly when clean. Do not use a spray on graphite product on aluminum.

Did you lube the alignment pins, and if so, did the nose portion of the cavities get contaminated (usually by lube migration from the pins)?

I doubt that your problem is venting.

Well, the 6 cavity mold I got recently has deeper venting cuts and works like it should. The problem mold does drop useable boolits so I will keep working with it. My best boolits from it are frosty so it likes more heat. Will try getting the sprue plate hotter.