4-banger -156 mold with problems

[Echo]

I have a 4-cavity Lyman 358156 mold with problems. It appears that someone has 'cleaned' it up with a wire wheel, leaving some burrs on a couple of the cavities. Note the cavities on the left. I'll bet that SOMEONE out there has a way of recovering from this mistreatment. If so, PLEASE get in touch! I would like to recover this mold, but don't have the means or talent...
189283

[TexasGrunt]

Pencil eraser, hardwood dowel, very careful Dremel work, 0000 steel wool. All are possibilities.

[runfiverun]

Lapping is your only hope.
it will round out the cavity's and enlarge the low spots.
you'll need to clean/cut the vent lines carefully and remove the burrs.

[rancher1913]

that one cavity looks like it is going to "fin" pretty good, might be less trouble and headaches to just get a new mold.

[Mk42gunner]

Sadly, unless you can do the work yourself, I think you will be money ahead to buy another mold.

My idea is to chuck it up in a four jaw chuck on your new lathe and slowly enlarge the driving bands. Realistically, read my first sentence again.

Robert

[rintinglen]

Before I gave up on it, I'd take a look at the sticky on "WEET" lapping up at the top here. http://castboolits.gunloads.com/showthread.php?257858-Expanding-a-boolit-mould-the-quot-WEET-quot-method-(In-parts)
Take Care not to enlarge the gas check post, but the rest of the boolit could be lapped to make a useful mold, without resort to lathes, mills or machine work. (I know, when you have a hammer every problem looks like a nail.) I have a 4 cavity 311-419 that I had to lap for the same reason and it came out pretty good. It will take some time but you'll not be out much money--a tube of valve grinding compound is all.

[OS OK]

Eeew! That's 'mould abuse' of the first order!

A good start would be to put a permanent impression of those cavities up side the head of whoever did that!

If you use COWW's with a low Sn % when you get if repaired, could be it won't fin to bad.

Best-O-Luck . . . charlie

[TexasGrunt]

Eeew! That's 'mould abuse' of the first order!

A good start would be to put a permanent impression of those cavities up side the head of whoever did that!

If you use COWW's with a low Sn % when you get if repaired, could be it won't fin to bad.

Best-O-Luck . . . charlie

I've got a better one.

189377

Two RCBS 45-201 moulds brazed together. It actually does cast pretty decent boolits. The sprue plate isn't quite flush so ya get a bit of flash.

Needless to say it's extremely heavy. Much too heavy for my arthritic hands.

[Mk42gunner]

I've got a better one.

189377

Two RCBS 45-201 moulds brazed together. It actually does cast pretty decent boolits. The sprue plate isn't quite flush so ya get a bit of flash.

Needless to say it's extremely heavy. Much too heavy for my arthritic hands.

Wow, just wow.

Robert

[OS OK]

"These were 'desperate' men that done this."

[44man]

That is a real jewel! Just needs a tongue ring. :groner:

[Dusty Bannister]

At least you have one or two good cavities to work with to pour laps for the process. First cast from each cavity and measure with a micrometer to see if they are wide at 90 degrees from the mold seam compared to adjacent to the mold seam. Usually molds are not exactly round. You will probably never have a perfect mold, but perhaps you can reduce the fins enough to be usable.

If measurements are favorable, you might cast a large number of lapping bullets in the good cavities with a medium hard alloy as they will wear longer than soft bullets. You might also cast some in a soft alloy as they will be smaller in diameter to start the process. Remove the sprue plate and alignment pins and hand lap the face of both molds to remove a little metal from each half. The vent lines should show well for a depth gauge so you do not over do things. You might need to chase the vent lines when done for good venting. Clean the mold and put the pins back in to keep the blocks in alignment when lapping. Since you used a hard alloy and have removed a bit of metal from both mold faces, the lap is going to be pretty snug so a small grit will be needed to start (the rocks are taking up a lot of space in the hole) To keep things straight, this would be the time to carefully drill the center of the base of the bullet for a blunt sheet rock screw and install a screw in the bullet to spin the lap. Remove the drive belt from your drill press and hand turn the pulley to spin the media coated bullet and gently lap each cavity a little at a time to keep them uniform and begin to make them round again. Steel molds are going to take a long time, so you will need to be patient. You will need to be careful about the depth of the lap in the cavity or you will lap out the lube groove bands in the mold cavity.

Take your time and think it through and watch to see where the bullet base is so you do not remove metal in the wrong places in the mold. Depth into the cavity (length of the bullet) is important at this time. Keep the lap wet so it does not gall the surface and resist the urge to turn on the power to speed things up.

Try to keep the compound out of the gas check heel area of the mold so that remains unchanged or only changed a very little. I have cleaned up a mold in this manner, but never to the extent of your condition. Good luck and go slow and easy. This will be a labor of love, not a production.