Base not filling out

[JJC]

I have boiled with dawn soap and scrubbed the mold (aluminum) with a tooth brush. Sprayed with carb cleaner a few times. Tightened and loosened the sprue plate. Cast with #2 and WW +3%. Cast from 600 to 800 degrees. Boiling again right now. This is my seventh or so time casting with the mold, no keepers. What else can I do? Thanks, John

[Maven]

Are you using a bottom pour furnace or are you casting with a [full] ladel? The latter can make a difference.

[Larry Gibson]

If using a bottom pour furnace open the adjustment to allow the molten alloy to get into the mould quicker. Also don't hesitate to let the alloy run over a bit leaving a large sprue.

If using a ladle like the Lyman or RCBS drill the hole larger, hold the spout against the sprue hole with both mould and ladle horizontal and then turn together to pour the alloy into the cavity. whenthe cavity is full lift up the ladle spout and let the alloy run into the hole and also leave a large sprue.

Lastly, make sure any vents near the base are clear and "venting".

Larry Gibson

[JJC]

I tried the pressure pouring too. I am using a Lyman ladle how much larger should the hole be? Can it be made to big?

[Hickory]

Your sprue plate maybe too tight and is not allowing it to vent properly.

[JJC]

Casting with a ladle it's a pain with too loose a plate. I have tried holding the plate with my thumb as I poured. Same problem and the plate is HOT.

[JJC]

You's think a 1/4 inch hole in the ladle is to big? The next step down is about the size of the ladle spout. But 1/4" is way larger than the pour hole in the sprue. Does that matter?

[BABore]

About a 0.160 to 0.175 diameter hole is adequate in the RCBS/Lyman ladle. You are correct that too loose of a sprue plate will cause you grief and base flashing when ladle casting. Assuming your mold is clean like you said, and your pouring a healthy sprue, then your looking at venting at the base. Check the vent lines and scrape them out with a razor knife if your mold is of that type. If not, then you can hone a very small chamfer on the inside, top edges of the blocks. I use a diamond hone, stone, or very fine file to do this. Don't go nutz here. A couple thousandths chamfer will usually work. Just enough so you can see a fine line when the blocks are tightly together. If it doesn't work immediately, try just a bit more. Beware! Too much and you can get finning. Also, make sure your running your mold and the sprue plate hot enough. 3-4 seconds for the sprue to go from liquid to solid is about right.

[Maven]

JJC, A 1/4" hole will only succeed in spilling molten alloy everywhere besides the mold cavities. Try cleaning the mold again with denatured alcohol, 90% isopropyl (rubbing) alcohol, or mineral spirits/paint thinner (the clear, envronmentally unfriendly type) if you can get it. Dry the mold and bring it up to operating temperature and then smoke the offending areas with a butane lighter or wooden match. If none of the offered suggestions work, you may need to improve the mold's venting.

[JJC]

Breaking the edges scares me. Just sprayed it down with carb cleaner and put back together. Vent lines look fine. I never had such a hard time, then again i never had an aluminum mold. I appreciate all the help everyone [smilie=s:

[swheeler]

Breaking the edges scares me. Just sprayed it down with carb cleaner and put back together. Vent lines look fine. I never had such a hard time, then again i never had an aluminum mold. I appreciate all the help everyone [smilie=s:

Don't let it scare you, it is SOP now for all my Lee molds. I use a diamond hone and it does make a difference.

[Larry Gibson]

You's think a 1/4 inch hole in the ladle is to big? The next step down is about the size of the ladle spout. But 1/4" is way larger than the pour hole in the sprue. Does that matter?

That is what I opened mine up to. As long as the outside of the spout is still contoured so it fits inside the countersick of the sprue pour hole I've had no problems with alloy spillage. The trick is to keep the spout against the sprue plate for the "pressure" fill and then rotate it sideways while keeping the mould top side up to fill in and create a good sprue. I also hold the mould and dipper over the pot so any run off goes into the pot. I wear long sleave shirts, eye protection and work leather gloves as I also open the sprue plate by hand instead of beating on it. Sometimes with large bullets I allow all the remainder of the alloy in the dipper to run into and over the sprue plate and then back into the furnace. This always has given me filled out bullets with problematic moulds or alloys.

I will note that I am using the ladel on bullets of 300+ gr only. On smaller weight bullets I have no problems with the Lyman Mag 20 and the spout adjustment opened. You might try opening the spout in increments as a smaller hole may very well work for whatever mould you are using.

Larry Gibson

[JJC]

Well after cleaning, not altering the mold or ladle, started casting. I got exactly three perfect boolits. Cast up alot of "seconds". I'll keep working on it, maybe touch the edges with a stone? Thanks again Gentleman

[LongPoint]

Maybe its the carb cleaner. I believe some leave a residue after drying to protect the parts from corrosion. Good luck.

LongPoint

[onondaga]

Is your mold a Lee? They are not designed for pressure casting, IE. pressing a ladle spout or pot nozzle to the sprue funnel gate. Using that method could also be the cause of your problem. Checking Lee literature or a call to Lee technical will verify that. I agree the carb cleaner may be part of the problem too. Detergent and a brush is fine.

A good swirling pour works well with molds that even have no vents. Pouring dead center or pressure casting with Lee molds is detrimental to casting quality as turbulence will cut off the tiny vents on Lee molds. Lyman has different instructions for their molds and very different vents.

For the Lee molds keep the stream length from spout or ladle short-- from 1/8 to 1/4 inch long at most and position your mold so that it is not level but tilted about 5 degrees and don't pour dead center to the sprue hole. Pour half the diameter of the stream off center to the sprue hole. This asymmetry and tilt sets the metal to swirl into the mold and gives the Lee molds their best fill when all else is ok with alloy and mold temp. The swirl method will work well with other brands of molds too, but the Lee molds definitely don't like pressure casting unless the vents are enlarged to the size of Lyman vents and the sprue plate tension loosened to vent also. So, if you are working with Lee molds, use them as they were designed and you will be happier.

Gary

[BABore]

Is your mold a Lee? They are not designed for pressure casting, IE. pressing a ladle spout or pot nozzle to the sprue funnel gate. Using that method could also be the cause of your problem. Checking Lee literature or a call to Lee technical will verify that. I agree the carb cleaner may be part of the problem too. Detergent and a brush is fine.

A good swirling pour works well with molds that even have no vents. Pouring dead center or pressure casting with Lee molds is detrimental to casting quality as turbulence will cut off the tiny vents on Lee molds. Lyman has different instructions for their molds and very different vents.

For the Lee molds keep the stream length from spout or ladle short-- from 1/8 to 1/4 inch long at most and position your mold so that it is not level but tilted about 5 degrees and don't pour dead center to the sprue hole. Pour half the diameter of the stream off center to the sprue hole. This asymmetry and tilt sets the metal to swirl into the mold and gives the Lee molds their best fill when all else is ok with alloy and mold temp. The swirl method will work well with other brands of molds too, but the Lee molds definitely don't like pressure casting unless the vents are enlarged to the size of Lyman vents and the sprue plate tension loosened to vent also. So, if you are working with Lee molds, use them as they were designed and you will be happier.

Gary

No offense, but I consider that hogwash. I have no problem pressure casting with a Lee mold as do many others. Lee may advise the trickle method because all they sell is that little ***, "tits on a boar hog", half a teaspoon. What else can they advise without cutting their own throat. You'd be better off dunking the whole mold in the pot and wait til the bubbles quit coming up.:groner:

[Larry Gibson]

I've not had any problems "pressure casting" with Lee moulds or my Rapine moulds which are aluminum also. Come to think of it my TC .50 cal Maxiball mould is aluminum also and "pressure casting" is a must to get complete base fill out with it.

Larry Gibson

[onondaga]

Lee instruction for pouring is based on their design and materials as is Lyman, RCBS and all. Customers can be very loyal and think that instructions are transferable to other brands. Some molds of Lee will respond to pressure casting some won't at all. This is why their instructions reflect the method that works the best with their molds.

Lyman isn't perfect either. I just got their new Cast Bullet fourth manual. I have read 48 of 320 pages so far and there are 4 misspellings, six grammar and syntax errors, eleven sentence structure errors and the author says that pure lead has a BHN of 5 . He also condemns the use of ballistic fillers.

I have Lee, Lyman, RCBS and Shiloh molds. Each of my Lee's have my label on the handle that has the pot temp best for my metal and the corner dip time for best mold warming so that the first bullet comes out good. That information doesn't transfer to other brands or molds. It doesn't make me curse Lyman either.. I have a problem with steel molds in general that I don't have with aluminum. Finding a standard warm method is sensitive and difficult, much more so with steel than aluminum for me. Casting with steel molds generally has more culls for me at the beginning of the session and later I have to slow my casting cadence more frequently with steel also or I get over heating of the molds much more frequently with steel than with aluminum. The over warming causes more culls again in the same session.

I have many round ball molds too. The steel round ball are all coarse with very visible cutting lines, but the Lee round ball molds are all mirror smooth in their cavities because they are pressed or cherried on a mandrel. This doesn't make me curse Lyman and RCBS. It gives me a preference in round ball molds.

Lee doesn't say that pressure casting only works on *** molds, nor do I. I believe that consistent pressure casting is a particular skill as is consistent bottom pour or ladle casting. Design and engineering can be optimized for each method. Lee has chosen differently than Lyman and RCBS . They all work well with their associated techniques.

Gary

[old turtle]

I have no Lee molds but on my others I find that if the plate is to tight the base will not round out. Hickory may be correct. But you must play with the tension some times even as the mold gets hotter

[Sensai]

JJC, any chance of pictures of the "base not filling out" bullets? How long are you waiting before cutting the sprue. What are you using to lube the sprue plate? I have no doubt in your casting skills, it's just that both of those things have bitten me in the butt.

I normally cast 357 and below diameter boolits. When I started casting heavier 45 cal, I didn't wait long enough for the sprue to cool. I wound up ripping the center out of most of the bases. I've read that you can "sharpen" the sprue plate opening, but I never have.

Another time, casting for 30-06, I couldn't get the corners of the bases to fill out. I tried for several sessions, with the same results. Then I remembered that I had "preserved" the mould for storage with oil. When I cleaned it for casting I hadn't removed all of the oil from the sprue plate pivot. The body filled fine, but the corners of the bases were all rounded. A little electrical contact cleaner and some bee's wax and I was back in business.

[mooman76]

Make sure you are leaving a good size puddle on top of the sprue plate. It helps give the cavity extra lead to draw from when it cools and shrinks down. I think it also helps give a small amount of pressure too.

[JJC]

[QUOTE=Sensai;1082051]JJC, any chance of pictures of the "base not filling out" bullets? How long are you waiting before cutting the sprue. What are you using to lube the sprue plate? I have no doubt in your casting skills, it's just that both of those things have bitten me in the butt.

Don't have any pictures. You know when the alloy doesn't make it out to the edge of the mold? Just short of full diameter, that's what I'm getting on a regular basis. The sprue cutting is fine not tearing the base out, and pouring enough on top. The rest of the boolit looks great. I'm using Bull plate and have to learn to use it more sparingly. Even after cleaning without the lube I still get the same thing. I have a 45 cal RCBS and no problems. Thanks for the vote of confidence but i'm starting to doubt myself on this one. I am waiting on another mold to show up to compare and go from there. I appreciate everyones input, John

[onondaga]

John, Sounds like you have been really trying with the suggestions you have gotten and are still not getting good results. This may be a different problem than we have hit on. Next inline it would be reasonable to stop using the alloy you have been using completely. The lot you have may have Zinc, and if it has even 1/2 of 1% it will never cast well and look just like the problem you are having with the poor fill-out you describe.. The lot of alloy you have may not have sufficient Tin in it either; it could have floated up, oxidized and been skimmed away. Low tin will also give the poor fill-out you describe Try a lot of alloy you can afford from a very reputable supplier like Rotometals:http://www.rotometals.com/Bullet-Casting-Alloys-s/5.htm
They have a wonderful selection of certified alloys and also have a reasonably priced casting thermometer:http://www.rotometals.com/SearchResults.asp?Search=thermometer&Search.x=4&Search.y=6

It think it would be a shame if you lost interest in the hobby because of the difficulty you are having. But at this time I think you need to take a different approach to curing your problems and a good certified alloy and casting thermometer will definitely tell you if your alloy was bad and your temperatures were out of the ballpark.

Gary

[JJC]

I'm not loosing interest, if I did not shave all my hair off me head I would be pulling it out. I tried #2 alloy (certified) and the same thing. I used a thermometer cast from 600 to 800 degrees. I added more tin to the WW that had 3% to start with. Incase some had been skimmed off. I'm at a loss here. I have no problems with a RCBS 45 405, mold or alloy. I'm going to wait on another mold to show up, hopefully in the next week or so. Get the pot going and cast as usual. The boolits look great except the base. I read on another post about someone here getting so mad at a mold till he finally figured it out. Maybe some is technique and some is finding the sweet spot for this particular mold. Plus I like the boolit and want to hunt with it.

[onondaga]

You can also try another simple diagnostic method concerning the mold lube questions. A short term use of pencil lead Graphite on a very clean mold will tell you if your other lube method was a lube excess problem.

Yet again, you got to be sick of this now, clean the mold completely. You can cast about 20 times or so with no lube at all or you can cast about 50-100 times with #2 pencil lead as a lube. Scribble pencil on the mold guide pins and the top of the mold block and underside of the sprue plate. You can scribble a lot, just blow away the excess graphite dust. You really can't overdo that if you blow away the excess and it will work for a bit. This will tell you if your particular application method for Bull Plate, other lubes or liquid cleaners in the mold was the problem. The pencil is not a permanent lube answer, but it will tell you if your other methods were the problem.

Some may argue but I believe temperatures approaching 800 will separate the tin, float it and oxidize it away. You can certainly see the rainbow of oxide colors on over-heated alloy if you skim away the flux or sawdust to a clean surface to observe for a few minutes at 800 degrees. The rainbow is a sure notification of way too much heat. A dull silver gray color that sustains time indicates your metal is not too hot and not oxidizing quickly. If you can not skim your alloy to a shiny smooth silver, you have oxides or separated alloy components floating. lowering temp a bit and adding tin, fluxing with bees wax will re-alloy new tin, Then cover with saw dust and cast.

Gary

[geargnasher]

First, anything over 725 degrees is too hot if you have any tin at all in your alloy. Anything over 2% tin is really a waste IMO, and if you have more tin than antimony (easy to do with wheel weights), it is possible to have fillout problems due to the "free tin" in the alloy.

Second, it sounds to me that the sprue plate is too cold or has a venting issue, but mainly too cold. Pour a bigger sprue puddle and let the lead run off the plate to soak it good with heat.

Third, carbureter cleaners have a paraffinic oil added to their formula to lubricate choke and throttle linkages and reduce the tendency of carburetor alloy to surface corrode, so it shouldn't be sprayed anywhere near a boolit mould. USE BRAKE CLEANER INSTEAD.

Gear

[JJC]

The mold is clean. I put it down after the last time I cleaned it. I gave it a few dirty looks since though. I will give the pencil a whirl. Thanks, John

[JJC]

First, anything over 725 degrees is too hot if you have any tin at all in your alloy. Anything over 2% tin is really a waste IMO, and if you have more tin than antimony (easy to do with wheel weights), it is possible to have fillout problems due to the "free tin" in the alloy.

Second, it sounds to me that the sprue plate is too cold or has a venting issue, but mainly too cold. Pour a bigger sprue puddle and let the lead run off the plate to soak it good with heat.

Third, carbureter cleaners have a paraffinic oil added to their formula to lubricate choke and throttle linkages and reduce the tendency of carburetor alloy to surface corrode, so it shouldn't be sprayed anywhere near a boolit mould. USE BRAKE CLEANER INSTEAD.

Gear

Yes sir I have your first sentence in my notes, think it came from you? Had to try the higher temp. Seemed it worked for others. Fill out on the RCBS was better with 3%, I started with 2% and upped it. I tried a large sprue puddle and put the edge of the plate in the metal. I used Mag one break cleaner. Sorry used the two names interchangeably.

[cba257]

I used to work in a body shop is why I tried it to start with. Try going to a automotive supply store and get some "wax and grease remover" designed to be used before application of automotive finishes.

The "tail" solvents or what is left to wipe off, are such that impurities are lifted and suspended. Carb-cleaner and alcohol; while they work most of the time, may evaporate to quickly-- especially with porous aluminum.

I just got back to casting again, but this stuff works great. Temperature is all I ever have to worry about. Kinda expensive, but a quart will last two generations of casters.

NAPA is a good place to start. PPG, Dupont......... Just something to try.

[cba257]

I used to work in a body shop is why I tried it to start with. Try going to a automotive supply store and get some "wax and grease remover" designed to be used before application of automotive finishes.

The "tail" solvents or what is left to wipe off, are such that impurities are lifted and suspended. Carb-cleaner and alcohol; while they work most of the time, may evaporate to quickly-- especially with porous aluminum.

I just got back to casting again, but this stuff works great. Temperature is all I ever have to worry about. Kinda expensive, but a quart will last two generations of casters.

NAPA is a good place to start. PPG, Dupont......... Just something to try.

[Bullshop]

I have not fully read this whole thread as I am in a hurry to get started on a large casting order. If this has already been addressed forgive please.
I would like to say that when I have a base fill problem and the other common things have been addressed that venting has always cured the problem.
The last wee but of air held in the mold will cause the very outer edge of the base to not fill properly and leave a rounded edge.
If you in some way allow for that last tiny bit of trapped air to escape the base will fill nicely. A really simple way to do this is while the mold is cold hold something between the blocks like about twice the thickness of a match book cover. Then using a small three corner file gently stroke the top of the blocks at the line formed by the mating halves. When done there should be the slightest hint of a bevel to the top edge of each block half. This one mod has made so much difference to so many molds for me.
What used to be rounded edged are now clean and sharp and fully filled to the edge of the cavity.

[JJC]

That's where I'm leaning but don't want to admit that to myself. That's why I'm going to hold off for a few more days. If I cast before the other mold arrives I'm gona take all the suggestions and try them out, pencil, less tin, ect.

[BABore]

Come on, just do it!

Crack them corners!

Man up! Don't be a sissy!

You can do it!

Seriously, it's real simple. Just use a fine file or hone. Just a couple very light strokes on each corner. I've even used the ole lady's fingernail file in a pinch. Worst cast is it casts fine, but fins some if you overdo it. You'll have learned what is too much. The mold block tops can be easily resurfaced if needed.

I break the edges of all the molds I sell. Just did a couple a few minutes ago. Never had any complaints

[fryboy]

+ 1 on the vent , it really doesnt take much to chamfer the top edge and it is the last place that needs to vent two strokes with a diamond hone should do it IMHO just breaking a sharp edge should help , a foto would help in this case tho i'll be the first to admit that i'm not very good with them ( nor do i have a decent camera lolz ) if it's the last corner of the boolit or the very bottom ( top ? lolz ) and there is no lube on the sprue plate the venting sounds about right , if it's the top ( bottom ? ) couple of bands i'd suspect the alloy or too hot of a mold

[Boolseye]

JJC,
Aluminum molds need to be seriously hot. Heat that sucker up! Dip a corner in the pot for 15-20 seconds. They conduct heat (and lose it) much faster than steel molds. I had several hair-tearing sessions with my molds (all lee, I have 3 6-bangers and a couple twos). It was always a heat problem. Also check out Ranch Dog's primer on 6-banger technique.
-jp