Lead smear on block

[Echo]

How to get it off? Tried brass brush, no joy, tried scraping w/pocket knife, no joy, tried heating with torch and hitting w/brass brush, no joy. How do it?
220744

[Bazoo]

Id try heating the blocks by putting them in the melt for a maybe 5 minutes. Handles attached of course, and not submerged, but just rest the blocks on the top of the pot so the bottom of the blocks are in the melt so they'll become "over heated". Whenever I do that, I always like to rubber band the handles so they dont open and make it worse or fall in or something. Then I do whatever and come back, Open the blocks, keep them spread with my thumb and you can do some serious scrubbing with a cloth, OR, lots of times I use a stick (similar to a popcycle stick).

[Triggerfinger]

Try this:
http://www.castpics.net/subsite2/MoldMods/Mould%20Maintenance.pdf

[gwpercle]

How to get it off? Tried brass brush, no joy, tried scraping w/pocket knife, no joy, tried heating with torch and hitting w/brass brush, no joy. How do it?
220744
You've tried all the normal things that should have worked....pocket knife usually gets lead off.
Do you think the material is NOT lead ? Is it harder than lead? Zinc maybe ? What would stand up to a torch , brass brush and pocket knife.....this one's a mystery !

[243winxb]

Soak with Hoppies number 9 bore cleaning solvent. At least 8 hours, 24 is better.

Then try this razor blade to lift it. Dont damage the mold.

[reloader28]

Wow thats a big spot. Is it possible the mold is warped a bit?

[Oily]

I like to heat on hot plate then use a bamboo skewer with a sharp point to see if I can lift one edge somewhere on a vent line. Did this happen when you were casting or did you get the mold in this shape ?

[john.k]

Not a lead smear,but a repair to a blowhole in the iron with nickle rod.....I can see typical bubbles/slag pockets in the weld.

[Oily]

Good eye there john.k Saw the bubbles or slag pockets but it didn't register. Kudos my friend! That explains why the pocket knife didn't release the offender. Now does it affect casting or not ?

[zubrato]

Best thing I do is heat up the mold to casting temp on a hot plate.
Rub with the edge of a cold ingot and it will come off.


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[vrh]

When the mold is hot, I spray Ballistol on it and scrub with a bronze brush. Works for me. it also is lubes the mold.

[243winxb]

a repair to a blowhole in the iron with nickle rod. Interesting. New to me. I did notice the bubbles.

[upnorthwis]

I use a 3/4" wood chisel. Has never failed.

[ShooterAZ]

If it is a lead smear, I heat up the mold to temp and then scrape the spot with the sharp edge of a boolit base. Comes right off.

[Echo]

I like to heat on hot plate then use a bamboo skewer with a sharp point to see if I can lift one edge somewhere on a vent line. Did this happen when you were casting or did you get the mold in this shape ?

I got it this way on eBay...

[Echo]

Not a lead smear,but a repair to a blowhole in the iron with nickle rod.....I can see typical bubbles/slag pockets in the weld.

Well - that makes sense to me. The torch didn't touch it, and I found that interesting. Your explanation rings the bell. I guess I'll leave it as is, and see what kind of boolits it throws.

[gwpercle]

Not a lead smear,but a repair to a blowhole in the iron with nickle rod.....I can see typical bubbles/slag pockets in the weld.

I was thinking it might be a repair but was looking for a brass rod repair ....didn't think of nickel rod repair....I would bet money it's a repair.
Good call john.k

[KrakenFan69]

Wow. I'm kinda shocked how many people suggested taking a metal implement to the mold. I would never do that for fear of ruining it. Guess I'm just a chicken.

Kraken Fan #69

[Bazoo]

Never seen anything like that. What would cause the need for a repair like that?

[Boolit_Head]

Never seen anything like that. What would cause the need for a repair like that?

A Idiot...

[243winxb]

Tiny gas bubbles are called porosities, but larger gas bubbles are called blowholes[14] or blisters. Such defects can be caused by air entrained in the melt, steam or smoke from the casting sand, or other gasses from the melt or mold. (Vacuum holes caused by metal shrinkage (see above) may also be loosely referred to as 'blowholes'). Proper foundry practices, including melt preparation and mold design, can reduce the occurrence of these defects. Because they are often surrounded by a skin of sound metal, blowholes may be difficult to detect, requiring harmonic, ultrasonic, magnetic, or X-ray (i.e., industrial CT scanning) analysis. https://en.m.wikipedia.org/wiki/Casting_defect

[john.k]

If you want blowholes ,buy a Chinese machine tool........sometimes quite important areas of iron turn out to be thick filler in blowholes......the China iron also tends to be so porous that it disappears if you try to fill it with any arc weld......Best cast iron you will ever see is old diesel engine flywheels......Ive made a few molds from biggies.

[Echo]

I'll try casting some boolits tomorrow AM & see what's los - thank you all for your advice...

[Echo]

Well, I cast some - the ones from the OK cavity turned out OK (not great - needed more heat), but the ones from the repaired cavity, not so much. Good (?) bullet in front, others behind. And had to beat the **** out of the mould to get the front cavity to release. I will gladly GIVE this mould to anyone who would like to play with it. You pay shipping, is all.220811220812

[Bazoo]

Id like to have it. I love a new challenge, and If all else fails, could use it to practice HPing a mould before I try it on a better one.

[Mr_Sheesh]

Let us know your progress / results please? Interesting - Never seen a repaired mold since I only bought new, till recently.

[472x1B/A]

Well, I cast some - the ones from the OK cavity turned out OK (not great - needed more heat), but the ones from the repaired cavity, not so much. Good (?) bullet in front, others behind. And had to beat the **** out of the mould to get the front cavity to release. I will gladly GIVE this mould to anyone who would like to play with it. You pay shipping, is all.220811220812

Thank you very much for starting this thread Echo. My question is , what does the other half of the mold look like? Is it the same as the side you posted the pic of? Did the person selling this mold show the inside of the mold halves? Just being curious here, nothing else. In all the years I've been here on Castboolits, I don't think I've seen a mold pic like this one. Hope you have good luck with this one Bazoo.

[John Boy]

Eezox and a razor blade

[Bazoo]

I will report back if I make any progress on it. From the castings, i'd say there is some raised metal on the repair that might be all I have to do is somehow remove it. It'll be a learning experience for sure.

[Drew P]

Surprised nobody suggested bees wax. Seems to creep under and scrape off with wood after warmed up.

[Echo]

Thank you very much for starting this thread Echo. My question is , what does the other half of the mold look like? Is it the same as the side you posted the pic of? Did the person selling this mold show the inside of the mold halves? Just being curious here, nothing else. In all the years I've been here on Castboolits, I don't think I've seen a mold pic like this one. Hope you have good luck with this one Bazoo.

The other half is the same! I hadn't noticed (Duh!), but samo samo. I'm sending it to Bazoo for him to play with...

[Bazoo]

I started a new thread about this mould. Here http://castboolits.gunloads.com/showthread.php?361599-Damaged-mould-repair

[gnostic]

I'd try lead wipe away cloth like I use on my stainless handguns, it works well on them.