Advice on refurbishing a Lyman Mold

[avogunner]

I've acquired a nice 4C 358311 mold from a member here and functionally, it appears in great shape; cavities look pristine, the alignment good as well as the sprue plate fit. However, there is moderate to severe pitting on the bottom of the mold and the entire block and sprue plate are "in the white" (a quick note here, the seller did accurately note the condition and that it was a severely neglected mold in his ad). I'm suspecting that the initial cleanup/derust may have removed the blueing (i.e. evaporust?). Really, I'm not sure if Lyman's molds are normally "blued" but this one now definately seems in need of that. Anyway, I'm planning to take a file to that pitting and then "blue" the mold. I've seen mention in other threads that molds will "heat blue" during normal use but I've not noticed this before. Should I go that route or try Birchwood Casey Perma (Cold) Blue?

Looking forward to suggestions.
Thanks
Jeff

[Horace]

Cast with it, it will color up fine.

Horace

[theperfessor]

^What he said.

[M Hicks]

The FB and HP pins that are in one of my NOE molds ended up heat bluing themselves. I was kind of surprised to see it happen. I have never done anything or researched heat bluing so it was new to me. I would just ensure it is cleaned up to your satisfaction and cast away with it. As long as you store it properly there won't be any issues. Good luck.

[Nocturnal Stumblebutt]

With every Lyman mold I've restored, they slowly acquire a nice reddish brown finish over time that is similar in appearance to rust bluing. Just be careful with that file, lyman molds are SOFT and you can quickly remove a lot of metal

[country gent]

Instead of the file which can cause issues with square and rmove alot of metal, try a sheet of wet dry sand paper on a hard flat surface. Set bolcks on it and rub in a figure 8 pattern slowly shifting around to diffrent areas of the paper. wet with water and a drop or to of dish soap. Oil will work but can be an issue in the mold after wards. Work slow and easy. A drill press table saw table or even a window glass ( real glass) will work. This makes for a much flatter truer surface and is easier to maintain.

[avogunner]

Thanks for the input.....all good advice. I'll start working on it this weekend.
Semper Fi

[Wayne Smith]

Instead of the file which can cause issues with square and rmove alot of metal, try a sheet of wet dry sand paper on a hard flat surface. Set bolcks on it and rub in a figure 8 pattern slowly shifting around to diffrent areas of the paper. wet with water and a drop or to of dish soap. Oil will work but can be an issue in the mold after wards. Work slow and easy. A drill press table saw table or even a window glass ( real glass) will work. This makes for a much flatter truer surface and is easier to maintain.

The best surface for this or for the scary sharp method of sharpening is the platen from a copier or printer. Should be a lot of them available, in my experience modern printers last less than three years! It's a tempered glass already bound in metal.

[Donor8x56r]

I found neglected 8mm lyman mold some time ago-by 3rd or 4th casting session it gained nice bluing ad it works just perfect.

No worries :)

[tward]

+1 on the Country Gent. I use a flat marble tile from Home Depot, put a little water on the marble and then put a sheet of 320 or 400 wet and dry on and it will stick. Move the blocks in a figure 8 pattern with a little water on the paper, be sure to wash the mold well to remove the grit. Tim

[LenH]

I restored a mold over the weekend by soaking it in kerosene over night and scrubbed it with a nylon brush. works great. Thanks.

[Gtek]

The used molds and the new ones I pick up all need something in my world of OCD. I radius all the edges on sprue plate, removing the knife edges all appear to have. I put a piece of 600 wet on plate and check bottom, you will find a lot of times some push through from counter sink job. On the rusty ones, OSPHO- (phosphoric acid) with bronze brush and scrub. Take care in regard to internal edges, I start from outside and push to center cleaning vent lines to cavity. They will usually end up "in the white" where I clean with boiling dish soap water, clean with clean boiling water (demineralized). Then I cold blue, yes they will color after multiple heat cycles but I have heard of cold blue for easier release from cavities until seasoning from oxidation has occurred on internal cavity. No study or experiments, just makes me feel better. Contact Lyman and buy some of the new spring washers, then shim screw--required-- to eliminate the gouge washer. The only thing I would touch a file on is the outside corners of blocks. If the cavities, top surface, plate, are good, the rest is cosmetic. Gtek

[NoZombies]

Man, I'm always just happy if the cavities are good and sprue is flat and true. I clean the rest to stop any active rust, and make sure to store them properly, otherwise I don't care too much about "ugly"