Got a new mold in the mail yesterday.
- Thread starter waco
- Start date
waco
Springfield, Oregon
Yup.
waco
Springfield, Oregon
Whatever cutting oil Al uses at NOE while machining his molds sure is a bugger to clean out of the cavities!!!!
I washed and scrubbed four times with hot water, Dawn detergent, and an old toothbrush. I then boiled it in clean water for 10 min.
This is my normal pre for a new mold. I then ran it through four heat cycles in the oven. I cast a short run with it the other night with lots of rejects.
I fired up the pot again last night and cast a bigger run. I still got about a 60% reject rate. I might clean the mold again or just cast a few more times with it and burn the oil out! LOL
The keepers I got do look nice though. Can't wait to load and shoot some.
I washed and scrubbed four times with hot water, Dawn detergent, and an old toothbrush. I then boiled it in clean water for 10 min.
This is my normal pre for a new mold. I then ran it through four heat cycles in the oven. I cast a short run with it the other night with lots of rejects.
I fired up the pot again last night and cast a bigger run. I still got about a 60% reject rate. I might clean the mold again or just cast a few more times with it and burn the oil out! LOL
The keepers I got do look nice though. Can't wait to load and shoot some.
fiver
Well-Known Member
I haven't found a way around heat cycling them about 4 times.
I have filled them with citric grease cutter which kind of scares me since I kind of think the citric acid will etch aluminum.
engine de-greaser and washed them off with electric parts cleaner.
just cleaning them and heat cycling [by casting with them] them with at least one of those cycles getting them mold to about 450-f seems to be my best option.
I have filled them with citric grease cutter which kind of scares me since I kind of think the citric acid will etch aluminum.
engine de-greaser and washed them off with electric parts cleaner.
just cleaning them and heat cycling [by casting with them] them with at least one of those cycles getting them mold to about 450-f seems to be my best option.
Ian
Notorious member
Exactly, Chris. That's in the instructions, and it works. Lightly, specifically, means a "caramel-colored haze". I used to think smoking the cavities meant a heavy coating of black soot, and doing it that way always caused more problems than it solved so I quit entirely. In frustration, one time I read the NOE instructions and voila! perfect bullets. By the third or fourth session there's no longer any need for it.
A
AMTom
Guest
One of the reasons why smoking is so effective is that it involves applying flame to the cavities.
Heat is the best way to get rid of the oil. When I encounter a stubborn cavity, I cast rapidly with 800-850 degree alloy for a few minutes until the mold's overheated (8 seconds or so for sprue solidification). You'll see a whiff of smoke coming out of the cavity.
It can be destructive to bake a mold block at really high (500 deg+) temperature, which people sometimes do in desperation. But briefly subjecting the cavity surfaces to intense heat safely works every time.
Heat is the best way to get rid of the oil. When I encounter a stubborn cavity, I cast rapidly with 800-850 degree alloy for a few minutes until the mold's overheated (8 seconds or so for sprue solidification). You'll see a whiff of smoke coming out of the cavity.
It can be destructive to bake a mold block at really high (500 deg+) temperature, which people sometimes do in desperation. But briefly subjecting the cavity surfaces to intense heat safely works every time.
A
AMTom
Guest
I use an ultrasonic cleaner with hot soapy water on my molds before shipping, but the ones I make for myself I don't even bother with that.
For myself, I blow dry the mold with compressed air when I remove it from the lathe and just cast with it. IF the new mold gives me trouble, I crank up the heat for a few minutes, see smoke, and drop the temperature back down.
So, my cleaning/break in recommendation is to do nothing but cast. On the rare occasion of fill-out trouble, smoke it. (That's easier than explaining my hot casting solve)
For myself, I blow dry the mold with compressed air when I remove it from the lathe and just cast with it. IF the new mold gives me trouble, I crank up the heat for a few minutes, see smoke, and drop the temperature back down.
So, my cleaning/break in recommendation is to do nothing but cast. On the rare occasion of fill-out trouble, smoke it. (That's easier than explaining my hot casting solve)
Thank you.
I have done the no clean, just cast with a few Lee moulds recently and was amazed at how quickly they gave good bullets.
The concept of getting the mould really hot to burn off the oils makes sense.
I was not aware that you cleaned moulds for us up front. Nice to know they are ready from the get go.
I have done the no clean, just cast with a few Lee moulds recently and was amazed at how quickly they gave good bullets.
The concept of getting the mould really hot to burn off the oils makes sense.
I was not aware that you cleaned moulds for us up front. Nice to know they are ready from the get go.
Ian
Notorious member
I couldn't agree more, Walter.
Yes, me too, for a couple of years now. I do rinse the protective sticky Alox-like goo off the sprue plate and handles with some chlorinated brake cleaner and put a dab of ester oil on the sprue plate pivot bolt, but other than that they're GTG out of the box.
Now we know "the rest of the story" about why Tom's moulds don't require a lot of fussing to get them ready. I still use just a faint whiff of smoke on the brass moulds when they're new because if I don't, they have a tendency to "tin" like all brass moulds do until they acquire a non-stick patina from a few casting sessions.
If you guys haven't tried one of Tom's steel moulds, you don't know what you're missing.
Yes, me too, for a couple of years now. I do rinse the protective sticky Alox-like goo off the sprue plate and handles with some chlorinated brake cleaner and put a dab of ester oil on the sprue plate pivot bolt, but other than that they're GTG out of the box.
Now we know "the rest of the story" about why Tom's moulds don't require a lot of fussing to get them ready. I still use just a faint whiff of smoke on the brass moulds when they're new because if I don't, they have a tendency to "tin" like all brass moulds do until they acquire a non-stick patina from a few casting sessions.
If you guys haven't tried one of Tom's steel moulds, you don't know what you're missing.
Ummm, where else would one buy Accurate moulds but from Tom?
His moulds are works of art and cast exactly what you want. Time from order to delivery is amazing.