LEE Pro 4 20 bottom feed lead pot ...pros n cons

[Brokenbear]

OK a couple of qualifiers ..I'm casting with pure lead making round balls only in .320 .375 and .454 and casting into 2 cav Lee RB molds

I know pure lead is more forgiving than some of the alloyed mixes but still needs a reasonable temperature to flow
Also uncomplicated sphere and no lube grooves or krazy angles might allow a budget pot to do the job

So I am hoping this thrifty rig can handle a simple mission like the above but I am seeking any tips n tricks you Lee Pro 4 20 users would care to share

Thanks
Bear

[StuBach]

It’s really not a bad pot for the money. When I upgraded to the ProMelt 1 I decided to keep it and eventually may end up using to create a Premelt reservoir above my PM1.

The drip is manageable, I kept a stainless steel pan under mine and just periodically dropped the drips back in.

I would just ask though, why need for a bottom pour? Seems like a ladle setup would be more cost effective and achieve the purpose you need?

[Carrier]

Can’t help with round balls but I cast a lot of bullets for trapdoor black powder and handgun with a Lee 10lb and 20lb bottom pours using a PID with no issues. At the very least get a lead thermometer. For what I cast 700 to 800 degrees works depending on the mix and mould.
The 20lb pot does drip but the 10lb doesn’t.

[dannyd]

It’s a good pot still have two; casted lots of bullets with them.

[big bore 99]

I'm on my second one with no complaints. A little twist of the plunger with a screwdriver help with any drips.

[JonB_in_Glencoe]

In the last 11 years, I've cast tens of thousands of boolits and thousands of round balls, all with a Lee 4-20.
in fact, I just cast 1000+ 9mm boolits this morning.
IMHO, there is only Pros, no cons.

[JonB_in_Glencoe]

a helpful hint, when casting with pure Lead, I add 1/2% tin, then the projectiles stay shiney and don't age tarnish or get corroded.

[Brokenbear]

Wow !! ..quick and positive comments ..Thanks folks ! ..keep'em coming

I looked at just a melting pot and a good ladle like a Lyman but that combination was with in a few $$ of the Pro 4 20

[sghart3578]

I love my Lee pot. To minimize drips I try to keep the lead clean. I recently bought a new Lee 4-20 because I damaged my original one. It was full of lead and cold. It was sitting on the floor and I knocked it over. It turns out the fall had broken the heating element. It was at least 10 years old and still going strong.

I ordered a new element and decided to replace the bottom pour pot with a solid one. The old one was very dirty and rusty. Now I have two pots.

I clean and flux my lead before I pour it into ingots. Now, when I bring the ingots in, I place them in the ladle pot and flux them a couple of more times before I pour it into my bottom pour pot. Keeping the lead clean seems to eliminate a lot of the dripping issues I use to have.

I love Lee pots.


Steve in N CA

[jim147]

Should work good. You say pure lead but are you buying it in ingots? Don't smelt in a bottom pour. That is when you have the drips.

[dannyd]

To help stop the drips just add a long screw and spring

287621

[Brokenbear]

The 1/2% tin seems a good idea to keep shinny ..I guess the question becomes how much (if any to speak of) does it change the hardness ??

The reason I think it is an issue in my particular case is I am building these projectiles ..excuse me boolits for Colt open tops black powder revolvers whose frame configuration are not the strongest as well as the fact that the loading levers can definitely be quickly challenged not to mention potentially life shortening to the loading levers ..so I read

You will notice I bold printed "I think" in the previous paragraph ..that is because ..I'm old... 60 years of reloading ..some boolit casting in there as well as years of black powder shooting ...BUT BP revolvers are relatively new to me so I have yet to create my own experience history ..hence the "I think" and "so I read"

Hence I am carefully storing pertinent information for my learning curve

Thanks
Bear

[Brokenbear]

Actually years ago i bought a huge amount of lead strips intended for waterfowl decoys that are pure lead (still in the packages) ..if and when that runs out ..no dumpster diving for me when I can buy from Rotometals and cast boolits for less than $0.01 per

Bear

[Dusty Bannister]

If you are using pure lead, the 1/2% of tin is so small it will likely not have any measurable affect. If you are using soft lead scrap, you probably have more antimony in the scrap and that has three times the hardening affect of tin. Unless you are using clip on WW you should not have any issues of hardness. Cast at about 800 degrees and have a very clean mold or you will have wrinkles on the castings.

[Dieselhorses]

Actually years ago i bought a huge amount of lead strips intended for waterfowl decoys that are pure lead (still in the packages) ..if and when that runs out ..no dumpster diving for me when I can buy from Rotometals and cast boolits for less than $0.01 per

Bear

LOL That's the first lead I ever melted! I don't think it's pure lead but close enough! Only mod I did was weld a big hex nut on top to give a little extra help in sealing. I use a PID and it keeps temp right around 720-730 F.

[imashooter2]

Many, many folks cast with the Lee pots as their primary, or only furnace. You will be fine.

[echo154]

Yep I have that very one. It is powered by a PID and drips like heck if I use it to melt dirty lead. For the price it is great...as are most Lee products....especially for beginners. Some of my favorite mold are Lee. Since I switched to a propane powered burner for smelting the dripping almost stopped....if I did it over I would go with the dip and cast model.....better quality pours. I use Lee sizers for 10MM, 44Mag and 45-70......just got a >451 for PP but then again I am just starting out in that endeavor so we shall see......bore in my BPCR is .450. I started out with a Lee mold .429 SWC and a Lee 44 Mag load kit....hand dies and capping.....I loaded some mighty accurate loads for my DW 44!

[OS OK]

If you want to increase production, you can run two or more moulds at the same time.
While one cools and solidifies the sprue, you are filling the other...set it down and break sprue on the first & refill. Repeat...

https://i.imgur.com/AjhqNDN.jpg

A little extra weight on the valve assembly will help with the dripping & something attached to the valve to allow you to reach up and give it a quick twist helps also.
If it persists or increases too much flow...take it apart and use some valve seating compound to seat the valve properly and then after that...keep your melt clean and don't drop sprues back as you cast or they will pull oxidized lead and tin down into the melt and that will eventually go through the valve (cause problems there) and go into your casts and cause problems there too.

https://i.imgur.com/Poyd9Lb.jpg

Parting thought...measure the bhn of that lead your using...know that it is soft enough to not damage that pistol loading system. You can measure bhn with an expensive test tool or with a pencil hardness...just know what your dealing with before you are fixing problems from not knowing.


https://youtu.be/HfsEDav4Sbg

ENJOY

[Soundguy]

I use their 10 bottom pour.. 20 could only be better. as others said.. drip is manageable.. I keep a spare ingot mold under. I hade ladle pouring...

[dannyd]

I use their 10 bottom pour.. 20 could only be better. as others said.. drip is manageable.. I keep a spare ingot mold under. I hade ladle pouring...

My 10 lbs’s never dripped had three at one time. Still may have one have to look.

[JonB_in_Glencoe]

The 1/2% tin seems a good idea to keep shinny ..I guess the question becomes how much (if any to speak of) does it change the hardness ??

>>>SNIP
1/2 % is also known as 200 to 1.
There is no added measurable hardness (as least measurable with hobby cast boolit tools).


Actually years ago i bought a huge amount of lead strips intended for waterfowl decoys that are pure lead (still in the packages) ..if and when that runs out ..no dumpster diving for me when I can buy from Rotometals and cast boolits for less than $0.01 per

Bear
It was mentioned that duck weights could be a harder alloy? Homemade duck weights surely could be made from just about any alloy, but if it helps you any, I have some commercially packaged duck weight strips and they are pure soft lead.

[Duckiller]

Many years ago I bought a Lee 10 lb bottom pour. First project was casting 45 cal round balls for daughter to roll cartridges, Used black pepper of powder. This was a 4th grade project. Daughter is now in her mid 30s. Either Lee bottom pour pots should work fine for your casting.

[Dieselhorses]

A little extra weight on the valve assembly will help with the dripping & something attached to the valve to allow you to reach up and give it a quick twist helps also.
If it persists or increases too much flow...take it apart and use some valve seating compound to seat the valve properly and then after that...keep your melt clean and don't drop sprues back as you cast or they will pull oxidized lead and tin down into the melt and that will eventually go through the valve (cause problems there) and go into your casts and cause problems there too.

I guess you learn something new everyday. So you saying "don't" continuously keep dropping sprue's into melt as you cast? (That might be one of my issues LOL). At the end of casting session and pot is about empty is it ok to throw all sprue's back in pot? Thx

[RydForLyf]

I guess you learn something new everyday. So you saying "don't" continuously keep dropping sprue's into melt as you cast? (That might be one of my issues LOL). At the end of casting session and pot is about empty is it ok to throw all sprue's back in pot? Thx

Some do and some don’t. I belong to the “do” camp. I also add a new ingot every 6th or 7th pour to keep the pot full and keep up the rhythm.

[gwpercle]

I use a open top Lee Magnum Melter 20 lb. capacity , with a Lyman spouted dipper ,
no drip , lotsa lead .... gave the pesky 10 lb. bottom pour to a fellow member who lost equiptment in a house fire ... He has since dumped it for a open top pot and dipper too .

The 20 lb . Magnum Melter has the 10 lb bottom pour pot beat Seven Ways to Sunday , I don't care what the experts say ... I cast better boolits with a dipper ...
Gary
PS - You can catch the Magnum Melter on sale ... it's a real bargain .
The 20 lb. capacity eliminates the need to keep tossing sprues back in and to not have to keep adding ingots , thus cooling down the mix ...
Get the metal hot ...20 lbs lets you cast enough with out the constant cooling down and warming back up ... it stays hot and lets you cast at a good rate of speed ...you get more better boolits ...Trust Me , I learned this the hard way !
Gary

[Mk42gunner]

Out of three different design bottom pour pots I have had, (Lee 10 pound, Lee 4-20, and RCBS Promelt), the only one I have had deluges from is the ten pound one.

The 4-20 is a fine pot. You can ladle from it if you want, and the drip art is eventually self limiting; at least on mine.

The Promelt still drips a bit, but not as much as the Lee. I would not pay the difference in retail price for a Promelt.

I did lap the valve and seat on my 4-20 before plugging it in. If memory serves I used 800 grit lapping compound.

With a bottom pour pot and a Lee 2 cavity RB mold, you can definitely feed two or three C&B revolvers.

I do like using the Lee Magnum Melter with an RCBS lead ladle better, but for pure lead RB there is absolutely nothing wrong with using a bottom pour pot. It may be the easiest casting session ever. Fill, twist the sprue plate, open and shake, close the mold, close the sprue plate and refill.

I do drop the sprue back into the pot. It is already warm, why waste the heat? Plus I usually catch the sprue in my gloved hand when it is cut.

Robert

[John Guedry]

I have a 10lb Lee bottom pour that was given to me by a friend about 25 yrs ago. It has survived being dropped and involved in a flood. Looks like the devil but works fine. When it "wears out" I'll buy a 20#.

[OS OK]

I guess you learn something new everyday. So you saying "don't" continuously keep dropping sprue's into melt as you cast? (That might be one of my issues LOL). At the end of casting session and pot is about empty is it ok to throw all sprue's back in pot? Thx

Whenever you decide to refill the pot with sprue cuts and new ingots, take the time to stir well, dip off the crud & oxidized metal that will not stir back in and cap the melt with a generous amount of wax. That'll minimize the oxidation as you run another pot full.

There's any number of ways to run a pot, I just want to have the cleanest casts possible (and the cleanest looking PC'd cast too) so being somewhat OCD, I go out of my way and take a little longer to get the job done. I am the one who has to be pleased with my work...nobody else.

What pleases me to no end is when a friend is over and we are farting around in the shop...they grab a handful of something I'm loading and say...
"Wow, where are you buying these?"
I reply..."I don't, I make them."

https://i.imgur.com/wtmZ6fZ.jpg

I guess what I'm trying to say is that 'great looking & great shooting projectiles' start at the cast bench with a 'clean melt'.

[dimaprok]

If Cast at about 800 degrees and have a very clean mold or you will have wrinkles on the castings.

There is absolutely no reason to run lead at 800 degrees, it will shorten the life of your pot and your molds. I cast my zinc bullets at 800, pure lead melts at 621 and its lower than lead alloys. 680 - 720 is plenty hot. I usually start hotter and when everything is running smooth I lower temperature to keep the lead solidifying faster.

If you're getting wrinkles just preheat your mold like Lee tells you in instruction manual by dipping mold edge in the pot or preheat it on the stove. If you're still getting wrinkles smoking cavities works 100%

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[Mk42gunner]

Good point about the temp.

I think it was Gearnasher who used to recommend casting at roughly 50 degrees F over the liquidous temp of your alloy. I tried it and it does work.

Robert

[kevin c]

I started with a Lee 4-20 and still use it, though now it's mounted over a ProMelt as a feeder pot. As a primary bottom pour mine was fine, and the dripping was just a little annoying. A PID gets around the drawbacks of the simple temperature control. I switched to the Promelt before getting the PIDs (both pots in the dual setup have them) based on the better temp control and reputation, and for the fact that the flat top made it much easier to preheat molds and ingots. It also made it much easier to mount the Lee on top.

ETA:

I cast at whatever temp that works for my cadence and environmental conditions, IOW, whatever maintains the molds themselves at optimal casting temp. For me, that's 720° to 740° using 95-3-2 alloy in 8 cavity aluminum 147 gr 9mm molds, done out of doors in moderate wind free weather.

[Brokenbear]

You lead slingers have really got me pumped up with all of your tips, short cuts, ideas and encouragement !!!

My 4 20 is hung up in transit (I caught where I ordered the 4/20 from with 3F Triple Seven powder which i bought and UPS is backed up hauling out hazmat due to federal shipping weight limits [below a certain total pounds is a flamable ..above that amount ..it gets classed somewhat like an explosive] ..) and UPS can/will only carry so many pounds total in a truck.

Any way ..I'm looking forward to implementing all these Ideas everyone is sharing ...

I chose the bottom feed over the dipper system because of rebuilt shoulders and arthritis in my hands make bottom pour more appealing plus I am not intending to process anything but pure lead ..no smelting ..alloying etc.

But that does bring another question to mind ..mold guide ..the one "built in" seems a bit shy on mold control ..I have looked on youtube as some of the "in the field" modifications mold guide wise but I would like to see some of your "field mods" if you would care to picture them for us !!

For a mold guide ...right now I am thinking a simple four sided 1/4" or 3/8" 4 sided steel box ..open end up/down and fit an aluminum top plate to it slotted for drips and aluminum angle stock to top plate to make adjustable guides n stops (Should be simple as every mold is Lee and the same size)

Thanks
Bear

[kevin c]

I didn't like the included 4-20 guide either: it scored the sides of my aluminum molds ("just cosmetic", sure, but like a scratch on the side of your new truck, not something to be pleased about).

I'm not good at making stuff (I can barely screw together two pieces of lumber), so I got a slotted mold guide from NOE along with an adapter for the Lee. It works well, though there's one issue to be aware about with a slotted guide: if alloy spills over the end of the mold and a drop freezes hanging off the end, moving the mold in that direction can jam the mold against the drip and slot.

[JonB_in_Glencoe]

I like Lee's simple mold guide. As Kevin mentioned, it'll scratch aluminum and brass molds, but if you grind a better curve in it, then polish it, and I will actually lube it with sprue plate lube...it'll work slick and minimizes scratching, and is easy to adjust during a casting session if needed.
that's my 2¢

[OS OK]

I like Lee's simple mold guide. As Kevin mentioned, it'll scratch aluminum and brass molds, but if you grind a better curve in it, then polish it, and I will actually lube it with sprue plate lube...it'll work slick and minimizes scratching, and is easy to adjust during a casting session if needed.
that's my 2¢

I did pretty much what you suggest the first week of owning that pot but I knew that there had to be a better solution. I used it that way for a long time until I ran across a little piece of aluminum bar stock in my junk metal one day and then I saw the answer to the 'simple mould shelf'.

https://i.imgur.com/URm0Nrj.jpg

The adjustment clamp screw made from a small 'C clamp'...smaller than the one in the picture.
The slight 'dog leg bend' in the bar gets it forward of the spout, when it drips it ricochets off the back side of the bar instead of piling up on top in your way.

https://i.imgur.com/HFo4Blm.jpg

The edge is adjusted with a 'drill stop collar', they come in set's, I think from Harbor freight, cheap too (they don't work very well as a drill stop) but they work for this...

https://i.imgur.com/zOdxe1j.jpg

You can use the stop collar on either side of the mould, here the other side of this mould has HP pin shafts sticking out of the side of the mould...
if you have HP pin hardware hanging out the bottom of your mould, this is not a solution. If I used one of those moulds I'd leave the Lee rest on that post along with this rest, then you can use either one. Adjust the one your not using up or down out of the way.

[mdi]

With good maintenance/care, and clean alloy your Lee bottom pour pot should last a very long time. I have a Pro-20, the only pot I have had, ever, I got it in the late '90s and have disassembled and cleaned it several times and while I've cast many, many assorted bullets it still works quite well (for about 20 years I never reloaded or shot a jacketed bullet, lead only in 9 handguns and 4 rifles). I use an analog thermometer and don't have wandering temps. I use only clean alloy, stir and "flux" often and the only modification I made was a heavy handle.

[Brokenbear]

OS OK ...now that bar system mold guide is the cat's meow ..pure genius ..I'm in ..I will build one(I hope) as soon as I figure out how/who I can get threads cut for the set screw and a press for that 15 or so degree bend ...Is that 1" bar stock? ... and why the paint? ..would of thought lead and bare aluminum would of been a better combination unless the coating is acting as a "hardener" and a form of a lubricant to keep metal on metal gaulding in check??

Thanks
Bear

[OS OK]

OS OK ...now that bar system mold guide is the cat's meow ..pure genius ..I'm in ..I will build one(I hope) as soon as I figure out how/who I can get threads cut for the set screw and a press for that 15 or so degree bend ...Is that 1" bar stock? ... and why the paint? ..would of thought lead and bare aluminum would of been a better combination unless the coating is acting as a "hardener" and a form of a lubricant to keep metal on metal gaulding in check??

Thanks
Bear

Thank you Brokenbear...those are very kind words.

The round stock is only 1/2" aluminum and the black is powder coat (your right, it acts like a bearing and nothing gauls the aluminum), that was what was on the round stock when it started out in life as a cross-bar for the handlebars of a dirt bike.

https://i.imgur.com/fFHMX4y.jpg

The little adjustment screw used to be a 'C-clamp' and it's thread size is 10-32, those taps are available in any hardware store.

I got the bend in the round stock by putting it in a vise, warming it some with a propane torch and smacking it with a dead blow hammer until I got the bend I needed.

[Brokenbear]

Thanks OS OK ...I'm on it!
Bear

[reedap1]

I second purchasing the NOE mould guide adapter for the Lee, makes life easier on the hands

[AndyC]

...I got a slotted mold guide from NOE along with an adapter for the Lee. It works well, though there's one issue to be aware about with a slotted guide: if alloy spills over the end of the mold and a drop freezes hanging off the end, moving the mold in that direction can jam the mold against the drip and slot.
The slotted guide was annoying enough for me that I removed it and I now just use the NOE rod itself as a rest to slide my mold-blocks over while I cast, similar to OS OK's rest in the pics above.

[kevin c]

Hah, that’s a practical solution worth a try. Better than me trying to bend, drill and tap bar stock. Bending stuff, maybe this soft handed white collar guy could manage. The rest, not so much.


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[Soundguy]

There is absolutely no reason to run lead at 800 degrees, it will shorten the life of your pot and your molds. I cast my zinc bullets at 800, pure lead melts at 621 and its lower than lead alloys. 680 - 720 is plenty hot. I usually start hotter and when everything is running smooth I lower temperature to keep the lead solidifying faster.

If you're getting wrinkles just preheat your mold like Lee tells you in instruction manual by dipping mold edge in the pot or preheat it on the stove. If you're still getting wrinkles smoking cavities works 100%

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Not everyone runs lee molds. I can tell you that multi cavity large brass block molds that have small cavities.. Like .225/35 gr... Those are very very very hard to keep warm using lead that is just at melting temp.

I run lead at 800 and make beautiful bullets. If my pot dies a year sooner..big deal..it was 55$... Each person should Run what works good for them and not worry about being bossed by others.

[dimaprok]

Not everyone runs lee molds. I can tell you that multi cavity large brass block molds that have small cavities.. Like .225/35 gr... Those are very very very hard to keep warm using lead that is just at melting temp.

I run lead at 800 and make beautiful bullets. If my pot dies a year sooner..big deal..it was 55$... Each person should Run what works good for them and not worry about being bossed by others.

Original poster specifically mentioned Lee 2 cavity large bullet design mold so IMO to cast at 800F is not a very good advice for the reasons I listed earlier. I am just stating my opinion, not bossing anyone around. For the record I did cast with Lee 224- 55gr 6 cavity mold and towards the bottom of the pot it was running empty and temperature dropped to around 660F and I was still getting wrinkle free bullets which surprised me actually.

The current price of Lee 4-20 pot from Midway is 75.99 plus tax plus shipping, not everyone can afford to just throw away the pot and buy a new one after few sessions of casting. You can cast at whatever temperature works for your particular mold, but I personally would not recommend someone to start casting at 800 degrees, if you're getting wrinkles - preheating the mold and smoking will solve 99% of the problems.

[Soundguy]

A few sessions of casting? That's hilarious... If a pot dies after a few sessions.. It's not the heat..its a defect. The pot is capable of running that heat. The 10# pots are cheaper. It's a tool.. Im not afraid of using tools. It's like buying a hammer but afraid to hit big nails with it ... This isn't advice and ymmv.

[Springfield]

I run 95% of my moulds between 675 and 685. This includes LEE 6 cavs from 32 acp up to 45-70, and many 4-5 cav NOE and Accurate, most in the 185-240 grain range. I have found no need to to hotter, but I have had to keep up the tempo more on some moulds than others. I have a PID so I can see the actual temp all the time.

[oley55]

A few sessions of casting? That's hilarious... If a pot dies after a few sessions.. It's not the heat..its a defect. The pot is capable of running that heat. The 10# pots are cheaper. It's a tool.. Im not afraid of using tools. It's like buying a hammer but afraid to hit big nails with it ... This isn't advice and ymmv.

especially when replacement parts are free from LEE. No phone calls, nor proof of purchase just go to their site, find parts, put them in the cart. when you go to checkout the parts are free but ya gotta pay shipping. Note of caution, this free stuff is for a single part. If you select two thermostats, you get charged for the second one, but you can have multiple different parts.

[Valley-Shooter]

This is what you need. Been using it for several years.

https://www.opennrg.com/product/lee-4-20-furnace-pot-upgrade-kit/

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[Mal Paso]

The Lee melters do not have a thermostat like Magma, Lyman and RCBS. To save money they use a bimetal switch similar to Infinite Controls used on electric ranges. It turns the heating element on and off every few seconds, the higher the setting, the longer the on time. Heat from the pot will slightly affect the switch but it is not a thermostat and has no sensor in or next to the pot. Typically as the level of alloy goes down the temperature goes up. Some casters have gotten very good at dealing with this, others have added PID.

PID uses a thermocouple and micro computer to learn the heating characteristics of the pot and apply exactly enough electricity to the heating element to keep temperature within a degree or two. It can switch several times a second so a Solid State Relay is best. They also switch between AC Cycles so No Electronic Noise.

Old School was a Mercury Thermostat which are difficult to get now. They worked well but had a dead band. Temperature would drop below cut in and the heating starts and does not stop until a higher cut out was reached maybe 10 degrees higher. Temperature would climb further until the element's heat was absorbed then start falling. It was good enough that most who have thermostats don't bother with PID.

[Brokenbear]

Well tomorrow's the day ..not my first time to cast boolits of course but it is my first session with a shinny new Pro 4/20 BOTTOM FEED ...
And my first session with 2 new Lee molds in RB .375 and .454
I unpacked the 4/20 mid week ... unplugged and free of lead to just look it over ... could not get the handle to lift as in to pour ..I guess the factory set them hard tight to lessen shipping damage to the rod and seat ? ..
So first piece of business is a guesstimate as to how much travel is appropriate ...I elected to allow very little travel ..I can always open it a skoch vs.. too much I could see a splattering mess ...
I suppose the 4/20 has gone thru some changes as I have seen pictures of a sort of locking screw near the rod head adjusting slot but mine has no means to "lock" the rod adjustment ..then on the other hand..
I understand that turning the rod back and forth as a means of possibly clearing a leaky seal/seat is expected ..so a locked setting on the rod may not be desirable ..
I will cast on my back covered but open sided back porch with 65 to 75 temps ..the question is ..can I alternate ..or will I need to alternate the molds in your opinion (time will tell of course) or will I barely keep just one in the temperature sweet spot!!??
Pot contents temp will of course play a roll ... here I am playing by ear using a laser temp taker(thinking 700*) ..which is another whole subject unto itself!!

Everyone have a safe and enjoyable holiday

Bear

[OS OK]

Well tomorrow's the day ..not my first time to cast boolits of course but it is my first session with a shinny new Pro 4/20 BOTTOM FEED ...
And my first session with 2 new Lee molds in RB .375 and .454
I unpacked the 4/20 mid week ... unplugged and free of lead to just look it over ... could not get the handle to lift as in to pour ..I guess the factory set them hard tight to lessen shipping damage to the rod and seat ? ..
So first piece of business is a guesstimate as to how much travel is appropriate ...I elected to allow very little travel ..I can always open it a skoch vs.. too much I could see a splattering mess ...
I suppose the 4/20 has gone thru some changes as I have seen pictures of a sort of locking screw near the rod head adjusting slot but mine has no means to "lock" the rod adjustment ..then on the other hand..
I understand that turning the rod back and forth as a means of possibly clearing a leaky seal/seat is expected ..so a locked setting on the rod may not be desirable ..
I will cast on my back covered but open sided back porch with 65 to 75 temps ..the question is ..can I alternate ..or will I need to alternate the molds in your opinion (time will tell of course) or will I barely keep just one in the temperature sweet spot!!??
Pot contents temp will of course play a roll ... here I am playing by ear using a laser temp taker(thinking 700*) ..which is another whole subject unto itself!!

Everyone have a safe and enjoyable holiday

Bear

Before you run any lead in the pot would be a good time to properly seat that valve with some valve seating compound.

[Brokenbear]

Thumbs up to lapping the seat

Bear

[Mal Paso]

The Laser guided Infrared Thermometers won't work on shiny surfaces. Float a piece of dark steel on the surface of the lead and read that or get a real lead thermometer.

[Brokenbear]

Well the deed is done ...I fired up today .. just a test run of the new Lee 4/20 and 2 new Lee 2cav roundball molds ..

Actually went well ..I was surprised ..I don't know why ..just a new way of doing something I've done for years ..

Now what's new to me is of course the Lee BOTTOM pour Pro 4/20 pot ..the new and operative word here is "Bottom Pour"

The other two wild cards are 2 factory new ALUMINUM 2 cav molds .. operative word is Aluminum ..I've never cast with aluminum

The pot was a dreamboat compared to my old dipping days! ..I lapped the seat on the valve (as was so wisely suggested) prior to first load up and no real drips as such but a little hang down 1/4" tit sometimes ..(temp?)

The cavity fill I soon learned needs to be fast and from the side (for perfectly formed boolits) rather than "hitting the hole" with a dipper

The molds I followed Lee's start up and break in instructions and used bees wax for lubing the sprue hinge screw and the two block aligning pins ..I re-lubed after the first 100 bullets on each mold ..the .44 mold I used first ..I notice a rub line on the top of the mold and correspondingly and aluminum line on the steel bottom side of the sprue cutter ..so I set it aside ...
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The .36 cal mold ran fine ..was able to cast fine balls in a very short time after learning on the .44 mold as to pour speed and pot temp ...speaking of pot temp..

Put the laser type temp meter on the lead and it gives an inaccurate reading ( as pointed out the reflectivity of molten lead foils the "whizo" type temperature gauge) ..HOWEVER ..if you place the laser dot just above the lead level on the steel rod to the valve and bingo you have a pretty good temp number ..

I realize I am casting a very very rudimentary boolit but the temperature management for ME.. which got me quickly casting smooth silver boolits was to just watch the sprue puddle ..thick, thin, wavy, frostie, shinny etc.

Bear

[Mal Paso]

Great job!

A little synthetic 2 cycle oil on a long Q-tip will clean that lead smear off a hot mold. I keep one ready while casting.

I've had good luck with Amazon Basics 6" cotton swabs. I've gotten a bunch that split in the middle before.

I thought all Lee Sprue Plates were aluminum.

[Soundguy]

Cutter plate is steel.

[Brokenbear]

OK synthetic 2 cycle oil to clean off the lead off the bottom of the steel cutter plate ..question ...

What does everyone do as to cleaning aluminum molds after use ??

I hope the curved line in the top of the mold is just lead because it looks a lot like aluminum removed and aluminum on the cutter plate ..I will get after it in the morning as soon as I figure out the proper clean up of the molds

Last question ..should there be any lube between the bottom of the cutter plate and the top of the aluminum mold block ?? ...Not wet of course but like a "film" so to speak?

Bear

[OS OK]

I rub anti-seize on the bottom of the sprue plate and top of the cavities (careful to keep it out of the cavities), rub it in like your wiping it off, it doesn't come off but it'll seal the metal from tinning.
I use the anti-seize on all the screw threads too.

[Mal Paso]

Check the steel sprue plate for burrs where the scratches are and remove them with a fine file.

I only have one Lee, a 6 cavity with an aluminum sprue plate.


Last question ..should there be any lube between the bottom of the cutter plate and the top of the aluminum mold block ?? ...Not wet of course but like a "film" so to speak?
Bear

I keep a 6" swab soaked with 1 drop of synthetic 2 cycle and use it to clean the top of the blocks and the bottom of the sprue plate when smears get obvious. A good time to do it is when the mold is a little too hot and a little cooling won't break the session.

[GregLaROCHE]

To help stop the drips just add a long screw and spring

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That’s a really good idea. I’m going to try that.

[dimaprok]

A few sessions of casting? That's hilarious... If a pot dies after a few sessions.. It's not the heat..its a defect. The pot is capable of running that heat. The 10# pots are cheaper. It's a tool.. Im not afraid of using tools. It's like buying a hammer but afraid to hit big nails with it ... This isn't advice and ymmv.

I mentioned in the first post I run it at 800F when I cast Zinc bullets and I dedicated 4-20 to it knowing that Zinc might eat through it. I am not afraid to use it. My Lee magnum melter I insulated with Kaowool, it was reaching over 900F on lowest setting (2). Added larger pot too, it would hold about 28lb of lead, melted lead, melted zinc, annealed 22LR jackets, eventually the pot sprung a leak, so I replaced it with one from Lee, just paid the shipping and rebuild it. I also replaced the heating element, the old one was scaled and chipping. Believe me, I used and abused my "tools" and what I learned is no need to run it super hot when its not required.