Help With Sticky Mold

us920669 · February 23, 2016, 11:08 AM

I've got a new RCBS cast iron mold that's the worst I've ever had for not dropping the boolits (I like this new word). Sometimes I can't even get the handles apart. I've read about using Comet to polish the cavity - is that OK with cast iron? How about a mild polish like Flitz or Metal Glow?

Beagle333 · February 23, 2016, 11:43 AM

Scrub it out very very well with a toothbrush and Dawn dish liquid and then get it hot. Preheat with hot plate if you have it, and then cast like mad until you get frosted boolits. Don't put the sprues back, don't cull the bad ones, don't admire the good ones, just cast and cast and cast. It should start dropping much easier before it gets to frosted status. I wouldn't imagine that you'd need Comet on a brand new RCBS mold.

Mike / Tx · February 23, 2016, 12:27 PM

If you have one of those lighted magnifying glasses, you might drag a Q-tip around the edges of the cavities. It could be you have some burrs left from machining that are holding things together, if so the fibers from the tip will hang up on them.

If this is the case and your REALLY careful with something like a Xacto knife you can simply drag it along the edges to smooth them down. This is of course the last thing you should try. I would follow up with what Beagle posted up as that is the easiest fix that usually works. Out of several dozen molds I have only had to drag a blade on two of them I purchased used, and they were in terrible shape when I got them, how many other hand(s) later....

Beagle333 · February 23, 2016, 12:40 PM

I have gotten some aluminum ones that had that little bit of extra on the edge of the molds that held onto the boolits. I can't say as I've ever seen it on a Lyman or RCBS iron mold...... 'cause I've never had a new one.

I always bought mine through some forum or fleabay.

us920669 · February 23, 2016, 01:48 PM

Many thanks. Seems like I spend so much time beating my handles half to death that the mold can't get hot. I don't think there's any edge roughness. I'll melt again tomorrow.

Mike / Tx · February 23, 2016, 04:44 PM

The two I referred to both looked like they had been beaten with a claw hammer. I doubt seriously they did them any good using whatever method they used prior to my getting them.

Follow Beagle's advice and you should be good. He seems to buy(acquire) more molds than I do and prolly has more experience with them as well. He does seem to have the only Cast Boolit Hall of Fame that I know of.....

Beagle333 · February 23, 2016, 07:25 PM

Mine just looks purdy 'cause I paint em all nice.

Let us know if getting it hotter makes it drop.

us920669 · February 23, 2016, 08:52 PM

I sure will. It's a 416 350 FN, so I doubt if I could have found a used one. There is one on ebay right now, but the guy wants more than Midway gets for them. It's for my new 416 Ruger toy, or it will be when the barrel gets here. It'll go on a Mauser - don't ask me why. If I go back to Africa I could take it, but I suspect Africa is the rearview mirror for me. I'll prolly just work up some loads & whoop and holler the first couple times it goes off.

Gster · February 24, 2016, 08:25 PM

Comet won't hurt that mold at all. Use the bullet that came out of the cavity. Drill a small hole in the center of it deep enough to insert a screw in it. Coat the bullet with a runny mixture of comet and water and spin the bullet in the cavity with a cordless drill and mold closed tightly. Scrub with water, dry and your bullets will fall freely when you open the mold. I've done this to several of my molds and it works great.

Gster · February 24, 2016, 08:27 PM

Comet won't hurt that mold at all. Use the bullet that came out of the cavity. Drill a small hole in the center of it deep enough to insert a screw in it. Coat the bullet with a runny mixture of comet and water and spin the bullet in the cavity with a cordless drill and mold closed tightly. Scrub with water, dry and your bullets will fall freely when you open the mold. I've done this to several of my molds and it works great. You can do this with lapping compound to enlarge bullets that drop too small also.

us920669 · February 24, 2016, 09:19 PM

I did the detergent scrub and cast until the storm front came through, with a possibility of tornadoes. The mold is a little better - it went through a phase of hairy monsters and for a while the blocks didn't align very well, but that all passed and it seemed to settle down after about an hour.
The halves continue to stick together and I found what might be a good system. I pull the handles while walking the mold around on the towel - not banging it at all, just letting its weight thump on the table. Pretty soon it starts to open up at the bottom, and when I see that I start opening and closing it until it pops open and the boolit often falls out or taps out easily. I might do a gentle Comet lap tomorrow.
This is only the second new CI mold I have ever owned, the first being a 44 handgun mold I bought in the 70s. I think it was frustrating at first too, but now its fine, so I guess they all need to be broken in.
Thanks for all the advice.

Beagle333 · February 24, 2016, 09:27 PM

Did you make sure the block alignment pins are clean all the way around them? (no gunk at all where pin attaches to mold) and be sure put just a little sprue plate lube on them as well? For some reason, it sounds like sticky pins... maybe not perfectly lining up with holes.

Ole Joe Clark · February 25, 2016, 09:41 AM

Did you smoke the mold before using it? That might help.

jaguarxk120 · February 25, 2016, 09:56 AM

Once the mold is working correctly smoking is not needed.

In fact you shouldn't have to smoke any mold!!!

Beagle333 · February 25, 2016, 10:20 AM

Quote:

The halves continue to stick together and I found what might be a good system. I pull the handles while walking the mold around on the towel - not banging it at all, just letting its weight thump on the table. Pretty soon it starts to open up at the bottom, and when I see that I start opening and closing it until it pops open and the boolit often falls out or taps out easily.

I don't think smoke nor comet will help that issue.

The boolits are falling out, it is the misalignment of the pins that is holding the blocks stuck closed.

reloader28 · February 25, 2016, 10:51 AM

Yup, check the pins.
DONT SMOKE IT. I've smoked a couple molds as a last resort but all that did was fix my lazyness of a good cleaning.

us920669 · February 25, 2016, 04:32 PM

Well, I've been busy. One pinway did have a little of their stuff in it, my 6m/m jag fit real tight with a patch so they're clean now, but remember when I was wiggling them open the pin side opened first, and it still does. What holds the mold shut is the boolit, up around the grooves or base. I did a very gentle Comet treatment, not paste but white water and no power, just turned it by hand. I used a cold reject, probably undersize, maybe I'll go back with a bigger boolit and a thicker mix. I cast a little this afternoon - they look good and a few came out very nicely, but it still sticks some so bad I finally gave up cus I'm ruining my handles. The mold is now stone cold, disassembled, and a boolit is stuck in one half. I'm sure I could knock it out, but I wonder if I should leave it in and send it to RCBS.
I tried a lot of things - it's a bottom pour Lee, and I tried removing the mold just as I was shutting off the stream so I could see the last of the lead hit the sprue, and that might have actually helped a little. Maybe that means I have to ladle-pour this one.

mehavey · February 25, 2016, 05:51 PM

Quote:

...when I was wiggling them open the pin side opened first,...

I'm trying to make sure I understand...
You are healthily tapping the mold hinge w/ plastic/rawhide hammer and the mold still won't open?

...or are you just trying to wiggle it open ?

us920669 · February 25, 2016, 06:22 PM

My main problem is bullets wont drop out, and they stick so bad the molds usually don't want to separate. They eventually open one way or another. I found that if I wiggled them they would start to open at the bottom, at the pins, but it was the top - sprue side - that stayed locked. I was saying that if I got them to start to open and then shook them open-close open-close, it seemed to dislodge the boolit from both halves. It doesn't work every time. The real problem is that the mold doesn't let them go, both sides but mainly the sprue side.

mehavey · February 25, 2016, 08:44 PM

Tap the hinge while held loosely but still closed.
The mold will open itself at that point.

You may still tap some more to get it to actually drop
from both sides, but that's par for the course.
In fact it's normal.

us920669 · February 25, 2016, 09:40 PM

I appreciate all the help everyone has given. I've been casting for maybe 40 years, on and off, 60 years if you count me helping my daddy. I'm not an expert but I've used maybe 6 or 7 molds and I've never seen one as stubborn as this. I'm going to try the Comet trick again tomorrow with a bullet from later in the cast and a thicker mix of the slurry.

Jim Watson · February 25, 2016, 09:55 PM

Paul Jones' method worked best for me, even with a Lyman mold.
Pour lead
Let solidify
Push sprue plate around. If you can't swing it with a gloved hand you let it get too cold.
Still holding mold closed, rap the hinge with your mallet.
Put the mallet against the lower right rear corner of the right half and press in and away as you let the mold open.
The bullet should fall out or drop with only a little rapping.

One I read of but didn't not have to try.
If you think the cavity is "toothy" get some cold blue and rust remover.
Degrease the cavity and blue. Then strip the blue with rust remover.
Clean and repeat several times.

us920669 · February 26, 2016, 09:57 AM

I've noticed something a few times, may not mean anything. Close inspection sometimes shows little bumps along the edge of one or both grease grooves. They are not nicks, they look like bubbles. There is nothing in the mold corresponding to them and they are not on most boolits, although most boolits certainly are stickers. I couldn't get a better picture, the macro feature doesn't work well with bright objects. I probably wont cast today, it's gotten much colder.

Beagle333 · February 26, 2016, 10:08 AM

Contact RCBS. I bet they'll replace it free. Their customer service is second to none.

That one has problems.

us920669 · March 3, 2016, 11:45 AM

I sent RCBS an email, I prefer email to telephone these days, and they wrote back to send the mold in for evaluation. But I had become impatient and went ahead with the Comet scrub-out, with a thicker mix than before and several bullets, as they spin freely quite quickly. I did it by hand and not power. I think I did remove an area of roughness inside one of the grooves and the mold is working fine. Chances are the roughness was some kind of compound of theirs and not roughness in the actual metal. I tried to clean it earlier, including a full blast-out with non-filming brake parts cleaner.

February 23, 2016, 11:08 AM	#1
us920669 Senior Member Join Date: January 6, 2016 Posts: 181	Help With Sticky Mold I've got a new RCBS cast iron mold that's the worst I've ever had for not dropping the boolits (I like this new word). Sometimes I can't even get the handles apart. I've read about using Comet to polish the cavity - is that OK with cast iron? How about a mild polish like Flitz or Metal Glow?

February 23, 2016, 11:43 AM	#2
Beagle333 Senior Member Join Date: January 7, 2012 Location: Auburn, AL. Posts: 2,332	Scrub it out very very well with a toothbrush and Dawn dish liquid and then get it hot. Preheat with hot plate if you have it, and then cast like mad until you get frosted boolits. Don't put the sprues back, don't cull the bad ones, don't admire the good ones, just cast and cast and cast. It should start dropping much easier before it gets to frosted status. I wouldn't imagine that you'd need Comet on a brand new RCBS mold. __________________ . . . Have a Colt and a smile.

February 23, 2016, 12:27 PM	#3
Mike / Tx Senior Member Join Date: April 8, 2000 Posts: 2,101	If you have one of those lighted magnifying glasses, you might drag a Q-tip around the edges of the cavities. It could be you have some burrs left from machining that are holding things together, if so the fibers from the tip will hang up on them. If this is the case and your REALLY careful with something like a Xacto knife you can simply drag it along the edges to smooth them down. This is of course the last thing you should try. I would follow up with what Beagle posted up as that is the easiest fix that usually works. Out of several dozen molds I have only had to drag a blade on two of them I purchased used, and they were in terrible shape when I got them, how many other hand(s) later.... __________________ LAter, Mike / TX

February 23, 2016, 12:40 PM	#4
Beagle333 Senior Member Join Date: January 7, 2012 Location: Auburn, AL. Posts: 2,332	I have gotten some aluminum ones that had that little bit of extra on the edge of the molds that held onto the boolits. I can't say as I've ever seen it on a Lyman or RCBS iron mold...... 'cause I've never had a new one. I always bought mine through some forum or fleabay. __________________ . . . Have a Colt and a smile.

February 23, 2016, 04:44 PM	#6
Mike / Tx Senior Member Join Date: April 8, 2000 Posts: 2,101	The two I referred to both looked like they had been beaten with a claw hammer. I doubt seriously they did them any good using whatever method they used prior to my getting them. Follow Beagle's advice and you should be good. He seems to buy(acquire) more molds than I do and prolly has more experience with them as well. He does seem to have the only Cast Boolit Hall of Fame that I know of..... __________________ LAter, Mike / TX

February 23, 2016, 01:48 PM	#5
us920669 Senior Member Join Date: January 6, 2016 Posts: 181	Many thanks. Seems like I spend so much time beating my handles half to death that the mold can't get hot. I don't think there's any edge roughness. I'll melt again tomorrow.

February 23, 2016, 07:25 PM	#7
Beagle333 Senior Member Join Date: January 7, 2012 Location: Auburn, AL. Posts: 2,332	Mike... Mine just looks purdy 'cause I paint em all nice. Let us know if getting it hotter makes it drop. __________________ . . . Have a Colt and a smile.

February 23, 2016, 08:52 PM	#8
us920669 Senior Member Join Date: January 6, 2016 Posts: 181	I sure will. It's a 416 350 FN, so I doubt if I could have found a used one. There is one on ebay right now, but the guy wants more than Midway gets for them. It's for my new 416 Ruger toy, or it will be when the barrel gets here. It'll go on a Mauser - don't ask me why. If I go back to Africa I could take it, but I suspect Africa is the rearview mirror for me. I'll prolly just work up some loads & whoop and holler the first couple times it goes off.

February 24, 2016, 08:25 PM	#9
Gster Senior Member Join Date: September 2, 2012 Location: N.central Pa. Posts: 302	Comet won't hurt that mold at all. Use the bullet that came out of the cavity. Drill a small hole in the center of it deep enough to insert a screw in it. Coat the bullet with a runny mixture of comet and water and spin the bullet in the cavity with a cordless drill and mold closed tightly. Scrub with water, dry and your bullets will fall freely when you open the mold. I've done this to several of my molds and it works great. __________________ Gun control means: Being able to hit what you are shooting at.

February 24, 2016, 08:27 PM	#10
Gster Senior Member Join Date: September 2, 2012 Location: N.central Pa. Posts: 302	Comet won't hurt that mold at all. Use the bullet that came out of the cavity. Drill a small hole in the center of it deep enough to insert a screw in it. Coat the bullet with a runny mixture of comet and water and spin the bullet in the cavity with a cordless drill and mold closed tightly. Scrub with water, dry and your bullets will fall freely when you open the mold. I've done this to several of my molds and it works great. You can do this with lapping compound to enlarge bullets that drop too small also. __________________ Gun control means: Being able to hit what you are shooting at.

February 24, 2016, 09:19 PM	#11
us920669 Senior Member Join Date: January 6, 2016 Posts: 181	I did the detergent scrub and cast until the storm front came through, with a possibility of tornadoes. The mold is a little better - it went through a phase of hairy monsters and for a while the blocks didn't align very well, but that all passed and it seemed to settle down after about an hour. The halves continue to stick together and I found what might be a good system. I pull the handles while walking the mold around on the towel - not banging it at all, just letting its weight thump on the table. Pretty soon it starts to open up at the bottom, and when I see that I start opening and closing it until it pops open and the boolit often falls out or taps out easily. I might do a gentle Comet lap tomorrow. This is only the second new CI mold I have ever owned, the first being a 44 handgun mold I bought in the 70s. I think it was frustrating at first too, but now its fine, so I guess they all need to be broken in. Thanks for all the advice.

February 24, 2016, 09:27 PM	#12
Beagle333 Senior Member Join Date: January 7, 2012 Location: Auburn, AL. Posts: 2,332	Did you make sure the block alignment pins are clean all the way around them? (no gunk at all where pin attaches to mold) and be sure put just a little sprue plate lube on them as well? For some reason, it sounds like sticky pins... maybe not perfectly lining up with holes. __________________ . . . Have a Colt and a smile.

February 25, 2016, 09:41 AM	#13
Ole Joe Clark Member Join Date: March 14, 2015 Location: Heart of Dixie Posts: 52	Did you smoke the mold before using it? That might help.

February 25, 2016, 09:56 AM	#14
jaguarxk120 Senior Member Join Date: February 28, 2008 Location: Michigan Posts: 2,620	Once the mold is working correctly smoking is not needed. In fact you shouldn't have to smoke any mold!!!

February 25, 2016, 10:51 AM	#16
reloader28 Senior Member Join Date: October 13, 2009 Location: nw wyoming Posts: 1,061	Yup, check the pins. DONT SMOKE IT. I've smoked a couple molds as a last resort but all that did was fix my lazyness of a good cleaning.

February 25, 2016, 04:32 PM	#17
us920669 Senior Member Join Date: January 6, 2016 Posts: 181	Well, I've been busy. One pinway did have a little of their stuff in it, my 6m/m jag fit real tight with a patch so they're clean now, but remember when I was wiggling them open the pin side opened first, and it still does. What holds the mold shut is the boolit, up around the grooves or base. I did a very gentle Comet treatment, not paste but white water and no power, just turned it by hand. I used a cold reject, probably undersize, maybe I'll go back with a bigger boolit and a thicker mix. I cast a little this afternoon - they look good and a few came out very nicely, but it still sticks some so bad I finally gave up cus I'm ruining my handles. The mold is now stone cold, disassembled, and a boolit is stuck in one half. I'm sure I could knock it out, but I wonder if I should leave it in and send it to RCBS. I tried a lot of things - it's a bottom pour Lee, and I tried removing the mold just as I was shutting off the stream so I could see the last of the lead hit the sprue, and that might have actually helped a little. Maybe that means I have to ladle-pour this one.

February 25, 2016, 06:22 PM	#19
us920669 Senior Member Join Date: January 6, 2016 Posts: 181	My main problem is bullets wont drop out, and they stick so bad the molds usually don't want to separate. They eventually open one way or another. I found that if I wiggled them they would start to open at the bottom, at the pins, but it was the top - sprue side - that stayed locked. I was saying that if I got them to start to open and then shook them open-close open-close, it seemed to dislodge the boolit from both halves. It doesn't work every time. The real problem is that the mold doesn't let them go, both sides but mainly the sprue side.

February 25, 2016, 08:44 PM	#20
mehavey Senior Member Join Date: June 17, 2010 Location: Virginia Posts: 6,894	Tap the hinge while held loosely but still closed. The mold will open itself at that point. You may still tap some more to get it to actually drop from both sides, but that's par for the course. In fact it's normal.

February 25, 2016, 09:40 PM	#21
us920669 Senior Member Join Date: January 6, 2016 Posts: 181	I appreciate all the help everyone has given. I've been casting for maybe 40 years, on and off, 60 years if you count me helping my daddy. I'm not an expert but I've used maybe 6 or 7 molds and I've never seen one as stubborn as this. I'm going to try the Comet trick again tomorrow with a bullet from later in the cast and a thicker mix of the slurry.

February 25, 2016, 09:55 PM	#22
Jim Watson Senior Member Join Date: October 25, 2001 Location: Alabama Posts: 18,541	Paul Jones' method worked best for me, even with a Lyman mold. Pour lead Let solidify Push sprue plate around. If you can't swing it with a gloved hand you let it get too cold. Still holding mold closed, rap the hinge with your mallet. Put the mallet against the lower right rear corner of the right half and press in and away as you let the mold open. The bullet should fall out or drop with only a little rapping. One I read of but didn't not have to try. If you think the cavity is "toothy" get some cold blue and rust remover. Degrease the cavity and blue. Then strip the blue with rust remover. Clean and repeat several times.

February 26, 2016, 10:08 AM	#24
Beagle333 Senior Member Join Date: January 7, 2012 Location: Auburn, AL. Posts: 2,332	Contact RCBS. I bet they'll replace it free. Their customer service is second to none. That one has problems. __________________ . . . Have a Colt and a smile.

March 3, 2016, 11:45 AM	#25
us920669 Senior Member Join Date: January 6, 2016 Posts: 181	I sent RCBS an email, I prefer email to telephone these days, and they wrote back to send the mold in for evaluation. But I had become impatient and went ahead with the Comet scrub-out, with a thicker mix than before and several bullets, as they spin freely quite quickly. I did it by hand and not power. I think I did remove an area of roughness inside one of the grooves and the mold is working fine. Chances are the roughness was some kind of compound of theirs and not roughness in the actual metal. I tried to clean it earlier, including a full blast-out with non-filming brake parts cleaner.