Something wrong

[4thebrdz]

I been castin for about 1 1/2 yrs now and have not had these problems.
I had been using the old dipper method and I was puttin out some great boolits. I got the Mag 20 pot and just haven't been able to get many good ones. Most of what I get looks like the mold is cold, wrinkles. The temp in the pot is 750* and holds pretty much right there. That was the temp I used with the dipper. I smoke the molds with a bic lighter and preheat them. Maybe I just don't know how to cast with the bottom pour.
Any suggestions?
Thanks

[Scrounger]

The pot probably had some kind of preservative chemical on it when you got it.

[longbow]

I have used a ladle and open pot for most of the last 40 years or so and prefer it to a bottom pour pot or even a Lyman style dipper with the little nozzle. I seem to have trouble with trapped air using the bottom pour pot or a nozzle that fills the sprue plate hole.

I may not be the best guy to advise but you might try checking the vent lines on the mould faces to make sure they are clean and open and it may also help to loosen off the sprue plate just a touch to help allow air to escape - not free swinging but not stiff to open.

[Crash_Corrigan]

Get some. See link at bottom of home page. The stuff is fantastic. Is your mold hot? Don't be afraid to dip it in the molton alloy to get it hot.

[Marlin Junky]

The problem with bottom pouring furnaces is that you need to keep the metal at a more or less constant level so the stream velocity into the mold cavity remains the same from cast to cast. You also need to turn up the heat to get your metal more fluid.

I can only assume you went to a bottom pour furnace to increase your production. I tried that too and was dissatisfied with boolit quality but then again, I only shoot rifles/carbines and am an accuracy buff. The way I increased my production with a dipper 2+ times was to buy a larger dipper (I went from an RCBS to a Rowell#2) and started using Bullplate sprue lube. With the big dipper, I fill my molds much faster and as soon as the sprue becomes solid, thanks to Bullplate, I can open the molds without smearing. There's definitely a technique to applying Bullplate properly and there's also a technique to using a Rowell#2, but if you're patient, it'll pay off.

Granted if you want to make piles of boolits with a 6-cavity Lee mold, you may be better off with a bottom pour because most pots (I have a 40# "MasterPot" from Magma) won't contain the run-off from a Rowell#2, but I can cast 10 pounds of good boolits with my system in an evening without wearing myself out... and without even adding metal to the pot.

MJ

[wiljen]

I place my mold on a hotplate and let it heat as my alloy melts. It usually still takes 2 or 3 pours through the mold before bullets start coming out looking like they should, but then I can cast quickly once I'm up to heat. Try pre-heating your mold and see if that doesnt make a big difference.

[lovedogs]

Each to his own. I used to use a dipper but now I prefer a 20# pot. Keep turning up your temp until you get some frosty bullets then back off cooler slowly and I bet you'll make fine projectiles once again.

[Kid Curry]

Sounds like your mold isn't hot enough if you're sure the lead is. I Keep my mold hot by laying on top of the pot, even letting the corner sit in the lead for a short time. I normally use two molds. Load one, put it on top of the pot, load another, switch, empty, load, switch, etc. Mold stays hot while it hardens nicely while I load the other.

I found bottom pouring to be easier and faster so retired the dipper. Problem with the bottom pour, however, is you have to watch it closer. I looked away once and was distracted long enough for the lead to leak all over the bench (burned it badly), melted a plastic tool box, and made a mess of the heavy duty carpet floor mat. All three pounds leaked out. I dare to turn my back on it now. If it starts to drip I immediately twist the rod to reseal it. Ed.

[Buckshot]

..................4thebrdz, You said you'd been casting for 1.5 years (dipper, right?) and you know about alloy and mould temps, etc, etc, since you've been doing fine. Now with the bottom pour you're having issues. Does the valve deliver a good solid stream of alloy? If not, it should. If it does, you will need to experiment a bit with how your mould wants the alloy delivered.

Some will do fine with the alloy dropping straight in through the sprue hole. Or you can try tipping the mould a bit, or tip the mould and let the stream kind of swirl in the cavity off the lip of the spruehole. This is some of the voo-doo stuff :-)

Or possibly your attire for dipper casting was fine, but now you're using a bottom pour furnace. Time to take stock of your dress. Personally for me, I've always had good luck wearing a jock strap, campaign hat and hurache' sandles. A hat seems to be de'riguer for some reason. You might start with a beanie with a propeller on top. I think 9.3x62AL finally had success when he went to a Bullwinkle the Moose hat, trading in the leather flying cap and goggles.

...................Buckshot

[JeffinNZ]

Guys, could it be Zinc contamination?

[dakotashooter2]

I'm inclined to agree with Buckshot .... It's a bit of voodo. Every mould I have wants something different and it takes a little while to figure out what likes what. Some like it hot, some not: some like to be held close, others like to be far away: some want to be overfilled others can't stand a sprue. I have one mold that just will not fill out with the bottom feed no matter what . That one gets the dipper. Keep experimenting till you find what works then do something that I need to do but haven't. Write it down cause if your getting older like me or your head has impacted the windshield one to many times sometimes the memory isn't so good.

[Pavomesa]

I've cast perfect bullets from cold molds so long as the metal is the right temp. The main culprit for wrinkled bullets coming out is some sort of grease or something in the mold. Take any mold and put a little film of oil in it and you'll find out real quick about wrinkled bullets.

It's irritating as hell but usually "cooks out" if you keep casting bullets after a dozen or so.

[felix]

It usually takes several casting sessions to make a mold perfectly cooperative. It takes time to get all of the evaporatives (farts) out of the minute cracks in the metal. Sometimes just two or three sessions, but rarely just one. It just depends on how much time the mold has had oils applied, and the kind of oil. The more creepy-crawly the oil type was, the shorter the time required to make the mold NOT cooperative on the first go-around. ... felix

This is prolly the best comedy record I have ever heard, bar none. Heard it back in the early 60's at an office party. It is a long recording, and very well worth 10 bucks. It is patterned after an official boxing match with bells, jeers, announcers and everything if I remember correctly.

www.thefartmachine.com

The International Wind Breaking Contest CD

[4thebrdz]

Buckshot- I don't wear sandles, just boots. I'll try the pin wheel hat and wear my leather welding coat. I don't have a jockstrap anymore, but I'll get some panties from Mama.
I gonna clean the heck of of the molds and use the voodoo you talk about. I do preheat the molds but will bump up the temp a bit. I have Dan's Bull Plate lube. I used it the first time this weekend. But the casting wasn't going to good with the wrinkles. We shall try again. Living on the dark side takes some education.
Thanks to all

[madcaster]

Is the adjustment of the lead pot allowing a good sufficent stream of lead to emerge?
Just a silly question,but maybe it will be helpful?:coffee:

[JSnover]

This is just a thought; Your current pot holds a steady 750 degrees. How accurate was the thermostat on your old setup? Could it be that your were casting at a higher temperature and didn't know it?
Funny things can happen when equipment gets upgraded.

[Razor]

Buckshot..

Personally for me, I've always had good luck wearing a jock strap, campaign hat and hurache' sandles.

BRRR!.. NOT a pleasant visual image !:groner:

Razor

[stocker]

I've found my bottom pour needs to be a bit hotter initially to really get the mould up to good operating temperatures. I usually start at 850 and after 20 or 30 pours cut back to 775-800 and she's good to go. I usually open the sprue plate hole a drill bit size at a time so I can keep a strong pour flowing freely. But, you have to be a bit quicker at shut off to avoid spills.

[oso]

. . . I have Dan's Bull Plate lube. I used it the first time this weekend. But the casting wasn't going to good with the wrinkles. . . .


If you get any lube in the cavities that can cause the problem you describe.

[cbrick]

Here is something for your mind to chew on. Everyone is familiar with air on the top of the pot oxidizing the alloy and that tin in the alloy helps reduce oxidation right? How many realize that the biggest benefit of tin isn't at the top of the pot but in the stream from the spout to the sprue plate where the alloy starts cooling (and oxidizing)? 4thebrdz didn't mention his tin content but this could possibly be a source of his problem with the bottom pour. With the ladle he would fill with clean alloy from below the surface, fill the mould from the bottom of the ladle when tilted and have far less air contact (or cooling and oxidizing).

He could add tin, pour faster, hold the mould closer, all of the above. If this is indeed part of his problem and his 750 degrees is accurate the suggestion of increasing the heat will cause his problem to get worse, not better.

Rick

[4thebrdz]

The thermometer I use and have for sometime is a RCBS. I feel it is and was accurate as it registers about 620 or so when the slush turns to melt. I add 1/2" of 50/50 bar solder to 4# of WW. I believe that pushes the tin content up 1 to 2%.

I plan to clean the molds very good and the pot. I think of hot water and dish soap and a tooth brush. I'll spray with brake clean the non-chlorinated type. Smoke the cavities, heat the molds up boost my pot temp, cast a few to get the temp right, and apply the Bull Plate lube to the sprue plate and mold top while the mold has a good filled out boolit bases in it.

I'll also put the beanie copter hat on.

What is the proper pour method for a bottom pour unit? Do you hole the sprue hole up against the spout or let the melt run into the mold with out it touching?

I thank you for all the replies

[PatMarlin]

This is prolly the best comedy record I have ever heard, bar none. Heard it back in the early 60's at an office party. It is a long recording, and very well worth 10 bucks. It is patterned after an official boxing match with bells, jeers, announcers and everything if I remember correctly.

www.thefartmachine.com

The International Wind Breaking Contest CD

THink that thing would pull in yotes?.. :mrgreen:

[GSM]

I'll also put the beanie copter hat on.

What is the proper pour method for a bottom pour unit? Do you hole the sprue hole up against the spout or let the melt run into the mold with out it touching?

I thank you for all the replies


Beanie copter hat is almost mandatory, although you are on your own as to which direction the propeller rotates.

Proper pour method tends to be dictated by the mould and each one may be a little different. It really does help to keep a notebook for each mould you cast with (I fight it each time and then wish I had when frustration sets in).

I have a couple of moulds that are happy to get the stream right down the center and some H&G's that refuse to cooperate unless the stream is banked off the side of the sprue hole. Go figure. Be sure to pour enough to leave a decent sprue puddle.