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captaint
03-30-2009, 09:05 AM
This must bore most of you guys to tears - however - On my second attempt at boolit casting I keep getting wrinkles.. I cleaned the mold (it's a new Lee 2 cav for 45ACP) and I get about 50 good boolits out of like 200. When I finished yesterday I cleaned the mold again in dish soap and heated it dry. Maybe I got some contamination from bullplate? Any help would be appreciated. Mike:veryconfu

docone31
03-30-2009, 09:12 AM
I do not believe it bores us. We all went through it.
Two approaches to lack of wrinkles.
Last resort, slide the sprue plate aside, heat up the mold, put a 1/4 20 nut on top of the sprue cavity, pour through and let it cool. Do this for both. Remove the castings with nut, smear a little valve lapping compound on the casting and one at a time, slowly and lightly close the mold on the casting while turning it. When it turns freely, do the other one.
Second, spray brake cleaner on the soapy mold, then let it sit in mineral spirits for several days.
In both cases, crank up the heat in the pot, and let the mold sit in the melt untill any lead that sticks to the mold beads up, and falls off. If the sprue takes forever to freeze, let it cool a little. If it freezes too quickly, let the castings sit in the mold after being desprued.
The main thing, is to keep a pace casting. Once the heat hits the sweet spot, keep it there by either holding the casting in the mold before water dropping, or dropping it quickly and waiting to refill the cavity.
The wrinkles are from lack of heat in the mold. You might try a little tin, but I found heat works better.
Hang in there, when it connects, it is a good feeling.

Shiloh
03-30-2009, 09:19 AM
What grit of valve lapping compound?? I am a novice on valve lapping compound. I have a need for this stuff for a mold as well as some binding parts. What are the available grits?

Shiloh

jonk
03-30-2009, 09:19 AM
Could be too cold; could be contamination from the lube; could be zinc in the alloy.

Wrinkled bullets are just fine for plinking. I sort mine- the good ones go in one pile, the slightly wrinkled ones go in another, and the really bad ones go back in the melt. The slightly messed up ones are fine out to about 15 yards, I see no difference over the perfect ones. Now past that, they do open up the group a bit. However as some of my shooting is indeed inside 15 yards, no reason to waste them. :)

44man
03-30-2009, 09:20 AM
Bullplate must be used VERY sparingly so it does not get into the cavity. It is great stuff.
Wrinkles are caused by a cold mold and cold lead if the mold is clean. Even if the lead is hot, a cold mold will not work.
Poor venting can cause a boolit to not fill out even if hot enough to frost.
Work on pre-heating the mold, keeping it at the right temp while casting by changing your pace and monitor the pot temp.
I had an old pot that had a worn out thermostat and lead would get cold as I cast. A few good boolits then rejects.

docone31
03-30-2009, 09:24 AM
I use fine lapping compound.
We do not want to cut a mold here, just polish it.
Again, it is mostly an heat issue.

captaint
03-30-2009, 09:49 AM
Thanks for the help guys. I've been threatening to try that fine compound on the boolit deal. Looks like now's the time. Also, I've been keeping the pot temp around 700 and trying not to let the mold cool off. I'll find a way to get it right. Thanks again, Mike

captaint
03-30-2009, 09:52 AM
I should mention, the pot temp is 700 ACCORIDING TO THE DIAL ON THE OLD PRO MELT. Been meaning to get a real thermometer too!

oneokie
03-30-2009, 10:13 AM
As others have stated, up your casting temp.

How long does it take for the sprue to harden after filling the mould? 2-3 seconds? Any quicker is an indication of a cold mould. Is the sprue hard to cut? If it is hard to cut, another indication of a cold mould. Your casting rhythm could be slow also. Try casting at a quicker pace.

docone31
03-30-2009, 10:17 AM
I prefer five to six seconds for both.

1Shirt
03-30-2009, 10:34 AM
Cast hot! I like to be somewhere between shiny and just starting to frost blts. As to wrinkles, if they arn't real bad, use them for 25-50yd MOBeercan loads. Hang in there!
1Shirt!:coffee:

wildwes
03-31-2009, 09:16 PM
I found getting my mould a little hotter as well as keeping the melt hot, to the point that they are frosting slightly to really help fill the mould out. Worked for me anyway.

geargnasher
03-31-2009, 10:17 PM
Please read the posts about "Lee-menting" to help fix wrinkles in new lee moulds in the moulds forum, helped me fix three rifle moulds I gave up on 15 years ago. I cast fairly hot, (especially with hollow points, they are their own animal) just under the temp where they frost (probably hotter than necessary, but it works for me), make sure the vent lines are open, make sure I have at least 2% tin in the alloy (when in doubt, add more) and cast in a smooth rhythm. Sometimes I have to cast 30 before the mold (especially steel) gets up to temp, just stay with it and suddenly the boolits just start working. Then after a while the mould will get too hot, and you will have to slow down and/or turn down the temp, it's a matter of constant adjustment until you hit the above mentioned sweet spot. Once I get started I cast 'till my hands cramp and then cast a few hundred more!
Hope this helps,
Gear