Bullet Mould Galling..any way to fix??

[Gary H.]

I have recently experienced the start of galling beneath the cutoff plate around the plate screw. This has occurred on a Lyman 457125 mould (I'm lucky it wasn't a custom mould) and now a gap is starting to show up between the mould and plate on the opposite side of the plate from the screw (i.e. the plate isn't perfectly flat on top of the mould because of the initiation of galling beneath the screw). This was likely caused because I didn't pay enough attention to keeping the plate lubed properly (with a mould prep or moly lube).

[u][b]My question[/b][/u]: Does anybody have a remedy for this condition? or is the mould finished? I have thought of refinishing both the top of the mould and the bottom of the cutoff plate, but would that ruin the base of the cast bullet? Any thoughts or comments would be appreciated.......signed: negligent mould owner!!!!

[Timberlake]

Gary,

Your mold is not finished. Take the plate off and polish up the bullet base side. With the plate off, carefully file the mold blocks just to remove any high spots. Reinstall the plate. Lyman molds work best for me when the plate is loose, not tight. Holding the dipper on the plate when pouring puts adequate pressure on it to ensure a good base.

TL

[Omak Cowboy]

Gary, others can speak to the repair process better than I but in reading your post it sounds like you are going to need to file or polish flat a damaged portion of the mold. Hence you are going to need a very flat surface.

In woodworking planes, chisels and other cutting tools need to be flattened even when purchased new from a high quality source. You can buy machinests quality surfaces - usually stone from what I see...OR you can use 1/4 inch thick or thicker plate glass - the thincker the better. Next get what ever grit of wet dry sandpaper you need, soak it in warm water for a 30 second or a minute until it's wet enough to adhere to the glass and go to it. Use lots of water on the paper to clear it and change paper often. Move up in grit grade until you have the kind of finish - polish you want. Using theis method you can very quickly achieve a mirror finish that is very flat on any kind of metal. Carefully set the glass aside for next time.
Omak

[Tasmanian Rebel]

Gary, I agree with Omak and Timberlake. Like timberlake I have found my Lyman mould works better a little on the loose side. On thing about polishing however, you may not want to get a mirror-type polish on the bottom of the sprue-plate. It may seal too well and not vent properly. Rdnck pointed this out to me recently when he dressed up one of my sprue-plates on his belt sander. I have had good results by putting mould prep on the top of the mould and the bottom of the sprue plate being careful not to get the stuff inside the mould where it can clog the vent lines per Paul Jones's recomendation.

[Jim B.]

Gary H.,
If you can bring your Lyman mould to Tucson's TRC 3-points range tomorrow between 8am and 2:30pm , I'll take it home with me and fix it up right for you, within a few days time. I'll be attending the monthly BPCR silhouette shoot there. Just ask for Jim Betush (Bettish).

[Lumpy Grits]

Hi Gary ; what I have had good luck doing is after I degrease the mold (I use a "brake cleaner" spray for this). I remove the spruce plate and with a "Q-tip" rub a VERY small amount of hi-temp anti-seize lube in the spruce plate pivot hole and on the top and bottom of the plate at that pivot point. And like the other folks said do not have the plate on tight. The anti-seize I use is NAPA's p/n 765-2569 in a 4oz. cont. it is copper based. [The silver looking stuff anti-seize that everybody sells will NOT hold up to the heat] Hope this helps.
P.S. Lyman sells replacement spruce plates for all their molds....

[Smokin]

Gary H,

The galling can be fixed or remedied. Take a good quality flat file and gently work away any high spots generated from the galling process. Be careful to hold the file loosely in your hand and let it seek its own mating to the surface of what your are filing. It must remain flat against the surface you are filing. That is, the surface of the file and the surface of either the mould block or the sprue plate must be in the same plane. You only want to remove high spots. Another solution suggested is using wet-or-dry paper and a piece of plate glass to lap the surfaces. This works too. Plate glass is generally ground flat and can be relied upon to produce a flat surface on what you are lapping. I would recommend using kerosene rather than water to both adhere the paper to the glass and float away the metal particles you are generating. If you use this technique, keep the material you are lapping flat against the paper/glass by not gripping it too tightly; let it seek its own reference to the abrasive system. When lapping use a figure 8 motion. This will even out the tendency you have to apply pressure in one direction and cutting material unevenly. You want to end up with flat and parallel surfaces when you mate the new surfaces of the sprue plate and mould block. These techniques will help. You don't have to over do it. It's the high spots which are the problem, not the divots. Good luck, Bruce

[Gary H.]

Thanks everybody for the super advice......I give the repair a try.

Jim, I'll look you up at Three Points one of these days. It only 20 minutes from my place. I travel a lot and am not at home at present, but I'll send you an e-mail so I can try to connect with you some day....thanks again guys.

[JAGG]

G H ! Just loosen up the plate screw ! It's not supposed to be tight in the first place and should swing freely ! If the cut off plate is warped , put it on a flat iron and place another flat iron on top and hammer it straight !JAGG