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jamesp81
02-13-2017, 12:31 AM
I casted about 150 boolits from a 2 cavity Lee 358-158-RF this evening. Of the 150, I kept about 20. Something is wrong with my technique and I really don't know what it is. I thought I would include a couple of pictures for those that actually know what they're doing to look at, and perhaps might have some insight into where my error(s) lie :-)

I'm ladle casting out of a Lee 20lb pot (non-bottom pour type). I have two ladles, one is the regular old Lyman dipper, the other is a home made contraption I made out of a stainless soup ladle. This second device was made more with six cavity molds in mind. I used it a bit with my two cavity mold here, but the vast majority of my casts were done with the Lyman ladle.

187922


Notice the rough looking area on the band right above the base. That band circles the lower band.


187924


There are two things going on here. Of course, there's that nasty indentation on the nose. Also notice the narrow rough looking bands on the driving bands themselves. This is similar to the roughness in the previous picture, but is more visible here. I've got LOTS of those. The majority of my rejects are from those that have that rough banding on the driving bands.


187923

I have more than a few of these with "cracks". Not even wrinkles, but what appear to be outright cracks. I get the wrinkled ones when my mold is cold, when I'm just getting started in a casting session. This one has me confused though. Possibly lead that isn't clean enough? Maybe I should flux more frequently?

clum553946
02-13-2017, 03:04 AM
Might preheat your mold on a hotplate, run up the temp some more, add a little tin, & work a little faster but still within the limits of safety.

bullseye67
02-13-2017, 03:35 AM
Good evening, You need more heat everywhere....Mold, sprue plate and pot. Try turning your pot to max and dipping the corner of your mold in the pot until the lead doesn't stick. Then heat both sides of the sprue plate with a small torch. Cast with max(10) setting until every boolit is frosty for 10 pours, then change to a (8) setting and keep casting all the boolits you want. It helps to leave the ladle submerged it the lead so it doesn't cool the pour.
A LEE bottom pour pot and a cheap hot plate would make your life so much easier......really....Titan shows the 10lb for $61.47 and the 20lb for $68.99 add Wally World hot plate for $10.00 and all your problems will disappear!!
Pictures are of the set up I use to cast over 300lbs of boolits a year:drinks: Cheers!

Wayne Smith
02-13-2017, 08:44 AM
More heat is the first approach - all of your failures look to be a cool mold. Start with a hotplate and what Bullseye said about managing your existing equipment. Don't throw money at a failure until you know the cause and the solution. It is likely you can fix what you have with minimal investment and learn a lot in the process. Then you can make some intelligent decisions about how to spend your money in the future.

Silvercreek Farmer
02-13-2017, 09:05 AM
What alloy are you using?

jamesp81
02-13-2017, 09:23 AM
What alloy are you using?

WW ingots from eBay.

GhostHawk
02-13-2017, 09:24 AM
Agree with the above. More heat, let lead get a bit warmer, mold a fair amount warmer.

Use ladle to pour lead over sprue plate, back of mold if need be. If you have to stick a corner of the mold into the liquid lead for heating.

Whatever it takes. Once you start casting ignore bullets, concentrate on maintaining cadence.

Cast 50, then let everything cool, while you look at boolits. Compare to these, note improvements. Decide if you need to be a bit faster, more preheat. Or, if you are getting good boolits run with it.

Write it all down, keep notes, every mold has its own quirks. Ladle should be submerged in hot lead when it is not pouring.

You can DO this, just need to learn what the signs are. In order to know what the landmarks are on a given road you have to walk down that road. Take your time, pay attention. But when casting just cast. Save admiring boolits for when casting is over.

jamesp81
02-13-2017, 09:28 AM
Good evening, You need more heat everywhere....Mold, sprue plate and pot. Try turning your pot to max and dipping the corner of your mold in the pot until the lead doesn't stick. Then heat both sides of the sprue plate with a small torch. Cast with max(10) setting until every boolit is frosty for 10 pours, then change to a (8) setting and keep casting all the boolits you want. It helps to leave the ladle submerged it the lead so it doesn't cool the pour.
A LEE bottom pour pot and a cheap hot plate would make your life so much easier......really....Titan shows the 10lb for $61.47 and the 20lb for $68.99 add Wally World hot plate for $10.00 and all your problems will disappear!!
Pictures are of the set up I use to cast over 300lbs of boolits a year:drinks: Cheers!

I'll get a hot plate today and try preheating as described. I will probably get a bottom pour pot at some point but not just yet. I want to learn the "original" techniques first, if you will. Same reason I'm not powder coating yet. I will at some point, but I want to learn first without it. Being able to make good bullets this way means I've actually learned something instead of compensating for poor quality.

And to think I was worried things were running too hot. You learn something new every time.

44man
02-13-2017, 10:35 AM
Do NOT put the mold on the coils. Use a plate of metal or a little oven made from an electrical box.
Your mold is too cold. I bring mine to 500° in the little oven, BBQ thermometer in the top. First boolits perfect and then keep a cadence to maintain heat.

Boolseye
02-13-2017, 10:48 AM
Yes, those problems almost always result from a mould that's not hot enough. You can dip a corner in the melt and leave it for a minute or more, too. that's what I do, as well as the surface of my wood stove. Heat.

Larry Gibson
02-13-2017, 10:50 AM
WW ingots from eBay.

Add 2% tin to your WW alloy. You can then add up to 50% pure lead to stretch it out. That alloy (WW +2% tin + 50% Pb) then will be fine for most 38/357 loads.

Use more heat; alloy should be at 715 - 730 degrees for casting.

If you are holding the mould with the top up and then just pouring the alloy in the hole it is wrong. Use the correct pouring method as shown in most Lyman manuals for use with the dipper. Pour each cavity separate.

With a 2 cavity Lee aluminum mould a hot plate is not really necessary as the mould can over heat very quickly if you are casting with too fast a cadence. Simply adjust the cadence to keep the mould hot enough to cast good bullets w/o over heating. Not hard to do but takes a little learning curve is all. However, the alloy must be corrected and at correct temperature or you will have a further hard time and a lot of rejects. It's not hard.

Larry Gibson

runfiverun
02-13-2017, 12:43 PM
your mold is cold.

your problem is your pouring technique.
you need to be smooth and fluid in your motions.
stop worrying about spilling a little lead and just make a swift decisive controlled pour.

monitor how much lead your putting in your ladle.
you'll find a spot that you use it all.
pour to the side of the sprue hole to let the air out.
or do the mate and twist on both holes then pour the excess on top of the plate.

casting is nothing more than refining your technique so you become proficient in your movements and it becomes a routine.

jamesp81
02-13-2017, 01:58 PM
Do NOT put the mold on the coils. Use a plate of metal or a little oven made from an electrical box.
Your mold is too cold. I bring mine to 500° in the little oven, BBQ thermometer in the top. First boolits perfect and then keep a cadence to maintain heat.

What about a hot plate that doesn't have exposed coils?

gwpercle
02-13-2017, 02:43 PM
I use the same Lee pot and Lyman ladle. Start with the dial set at 7.50 , mould on top of pot and ladle in the pot. Get the alloy , mould and ladle all heated up. If you don't keep the ladle in the pot with alloy in the bowl it will cool off and the alloy will not flow through the nozzel. I pressure cast with nozzel pressed against sprue hole.
If the mould , alloy, and dipper are all kept hot and the mould is cleaned of all oil, the alloy may be zinc contaminated. Don't know how to fix that.
I start at 7.50 on the Lee dial and when boolits start getting frosty, dial it back to 7.25 and leave it at that setting. Be careful heating a mould on hot plate...if overheated you can ruin them. I heat on top of pot, corner dip and fast cast a few to get to proper casting temperature. I haven't had to use a hot plate with a two cavity mould yet.
Technique is the key, a quick fill with a nice sprue puddle on top...that's what you're striving for. Cast over a old pizza pan or metal tray so any overflow can be caught , fill it fast and pour a full sprue on top.
Good luck.....Gary

GRUMPA
02-13-2017, 03:17 PM
If all that advise doesn't solve a thing, look into smoking the mould.

Some of the moulds I get just wont fill out till I smoke them, then they come out looking like they're supposed to.

jamesp81
02-14-2017, 12:20 PM
Lots of good info in this thread. I'll be trying new technique next casting session. Thanks to everyone :)

daloper
02-14-2017, 01:16 PM
If you don't have a piece of plate to put on your hot plate just use an old circular saw blade on the hot plate and set the mold on that.

44man
02-14-2017, 02:03 PM
My $8 plate has coils. Maybe more spent will be different.

John Boy
02-14-2017, 02:15 PM
Melt in pot and mold at same temperature - ladle pour for 5 -8 seconds and sprue puddle frosts in 5 - 10 seconds. If not - raise melt temperature. And Rhythm is the name of the game

Phlier
02-14-2017, 02:51 PM
Do NOT put the mold on the coils. Use a plate of metal or a little oven made from an electrical box.
Your mold is too cold. I bring mine to 500° in the little oven, BBQ thermometer in the top. First boolits perfect and then keep a cadence to maintain heat.
I warped my first Lee six cavity mold by doing this.
Yup, it's important to pre-heat the mold, but unevenly heating it is a very, very bad thing, especially if the mold is aluminum.

HeavyHev
02-14-2017, 03:36 PM
I bet the 20 you kept were your last 20 when your mold was at the proper temperature.

Oklahoma Rebel
02-14-2017, 04:22 PM
what is the technique lyman describes? I hold my molds even and pour right into the holes, well sometimes I let it hit the edge of the sprue hole and then trickle in. but I have never had problems just pouring right into the holes, so I am interested in this lyman technique you speak of.

jamesp81
02-14-2017, 04:46 PM
I bet the 20 you kept were your last 20 when your mold was at the proper temperature.

It's possible, but not entirely sure. I did weight 3 of these and their weight 160gr +/- 0.5gr, so I think they filled out fairly well. Not bad for the new guy anyway.

fredj338
02-14-2017, 04:58 PM
WW ingots from eBay.
I agree, more heat, but the ebay lead may also be the issue. You have no idea what you are getting as to alloy. Turn the heat up, flux it really well, then cast at 750+. You can also try pressure casting, the spout hard against the spru plate, then form your generous spru. Also make sure the mold cas are really clean, toothbrush & degreaser clean.

TexasGrunt
02-14-2017, 05:16 PM
what is the technique lyman describes? I hold my molds even and pour right into the holes, well sometimes I let it hit the edge of the sprue hole and then trickle in. but I have never had problems just pouring right into the holes, so I am interested in this lyman technique you speak of.

Hold then mold at 90°, put the spout in the sprue hole and tilt both the mold and ladle upright. Pull ladle away leaving a sprue puddle.

gwpercle
02-14-2017, 05:33 PM
Hold then mold at 90°, put the spout in the sprue hole and tilt both the mold and ladle upright. Pull ladle away leaving a sprue puddle.

It's also refered to as pressure casting.
The hardest part is leaving a full spue puddle. Not too much but just enough!
I usually don't leave enough or pour lead all over the mould and runs down the sides .
Mastering the puddle is the secrete to pressure casting.

runfiverun
02-14-2017, 06:14 PM
the lyman method is also called the twist.
you line the sprue up with the ladle face and make contact then roll them over mold side down and move your hands apart.
I do the roll/twist and count to 5 then roll back and do the next cavity.
then pour some of the remaining lead in the sprue holes and on the plate so I can get the sprues back off the plate.