Fixing the Drip-O-matic

[Petrol & Powder]

I finally had enough and pulled the side plates off my Lee 4-20 so I could fix an annoying problem.

The handle that operates the nozzle slides up and down on two screws that act as guides and limit the travel. The upper screw constantly worked its way out of the side plate and caused the handle to move too far or get hung up. The problem is that screw just has sheet metal type threads that engage an extruded channel inside the side plate. There just isn't much there for the threads to engage. It is a classic example of how Lee found a way to cut costs.

The quick fix was to just use a pair of pliers to compress the sides of that channel so that the threads had a little more purchase.

I think the next time I have that apart I'll fabricate a more permanent solution.

On a positive note, about a year ago I polished the nozzle seat and the tip of the metering rod and that stopped the dripping.

At some point in time I'll replace the 4-20 with a RCBS Pro-melt. For now I'm making the cheap Drip-O-Matic work.

[cwlongshot]

Its not just LEE Pots..



BUT< LEE can bring drips to a new level.



CW

[OS OK]

If you want your Lee 4-20 to work well...you will have to modify it some and use clean ingots and stop putting sawdust in there for flux. Ever now and then you must scrape the interior of the pot liner when it's empty and do a little preventative maintenance.

And...you never turn your back on a problematic pot and walk away from it.

[JonB_in_Glencoe]

I've found those two screws that act as slides see more than their share of abuse...if they aren't lubed, they can bind. I have oiled them with a tiny amount of Bullplate or Synth two cycle oil. I also lube the adjustment screw, As the alloy level gets low, I find myself adjusting while casting,and it turns much easier when lubed.

[Conditor22]

You need to be gentle with Lee drip-o-matics.

Lifting the vale knob harder will not make the lead come out faster, all it will do is loosen the top shoulder bolt that holds the valve arm assembly on. Another problem I found is that the further the vale knob sticks out from the pot the more strain it puts on the top shoulder bolt. (see double red arrow)
I also found that the closer to the pot you lift the vale knob, the easier it lifts with less strain on the shoulder bolts, also allowing the valve to close easier.



I'm planning on making either, a leather or thin plywood disk to fit between the Valve Arm Assembly and the Valve Knob so I don't have to worry about "jamming/placing" my finger as close as I can to the Valve Arm Assembly for a straighter lift.

Try lifting with just the tip of one finger, you'll be less likely to force it.

If the lead isn't coming out as fast as you want, lifting it harder won't help (I know I do this also )

http://castboolits.gunloads.com/show...-spout-cleaner

[Tom W.]

I have two, a 10 and a 20 pound pot. The smaller pot I used to use for casting pure lead. It is VERY old, and works fine. The bigger pot isn't quite as old, but it's far from new. Two years ago I was ready to throw it into the river, as it started dripping terribly. I drained it, cleaned it well and then took out the valve rod and polished it and the spout with valve lapping compound. That stopped the leak. I won't lie and say that it doesn't drip a little bit, but it surely doesn't pour out like it did.....
For the price paid and the service rendered, I ain't gonna complain about either Lee pot.

[jimkim]

I keep saying someone, with a shop, needs to make a bolt on lever mecanism for the Lee pots, that adds a spring to it. Something like this valve/lever assembly made to bolt to the top of a Lee pot, would fix the drip. I'd also lap the valve, and add a place for a pid sensor. The entire assembly could be attached to a piece of angle iron, and screw to the top of the Lee pot.

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[Dieselhorses]

I keep saying someone, with a shop, needs to make a bolt on lever mecanism for the Lee pots, that adds a spring to it. Something like this valve/lever assembly made to bolt to the top of a Lee pot, would fix the drip. I'd also lap the valve, and add a place for a pid sensor. The entire assembly could be attached to a piece of angle iron, and screw to the top of the Lee pot.

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I think I’m going to do that mod. Thx!


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[Petrol & Powder]

I fixed the dripping issue by polishing the valve seat and metering rod. I'm happy with that fix.

Those shoulder bolts (more aptly called sheet metal screws with a portion of unthreaded shank) are about as cheap as Lee could make that part. They screw into an aluminum channel and there's not a lot of metal there for the threads to 'bite".

I'm certain I can improve upon that design.

In the meantime, it's working as it should.

[Conditor22]

You could get a longer shoulder bolt for the Lee and put a washer and spring on it pushing the rod down

[KenH]

I fixed my leaking 4-20 Lee pot by adding a brass weight to the top of valve rod. That little bit of extra (3 oz?) weight presses a bit more on the seat preventing the leak.

[Green Frog]

I’ve got two of the “20 pound” Lees and have had a 10 and a 20# Lyman as well as having used a 20# RCBS a fair amount. Anyone who says they have ANY bottom pour pot that doesn’t drip isn’t using it very much! I just got another 10# Lyman (used) and before I put it or either of my Lees into use they will get a little lapping.. I’m also thinking hard about that brass weight that KenH mentions. I don’t suppose you’d be willing to post a picture of it, would Ken?

Froggie

[mdi]

And...you never turn your back on a problematic pot and walk away from it

.
General Shop Practice 101; never leave a machine unattended (or any powered, electrical equipment). I have been using my Lee Pro 4-20 for maybe 18 years. If the alloy is not clean, the pot will drip. If the lever screws work loose, the pot may drip (but it is a well known phenomenon that constant/repeated heating and cooling will "loosen" screws, but there is high temp. Lock Tite). I added some weight to the valve operating handle via lead washers and my pot leaks very little. But, as my usual shop practice, I keep my equipment well maintained and clean. I occasionally empty my pot, wire brush the ID, and clean the needle valve and seat. No big deal, just proper tool ownership, maintenance...

If you just melt, pour, and turn off your pot, expect less than optimum service, and don't whine about cheap equipment...

[Nodakjohns]

I am glad I found this place ! I have only had 3 casting sessions in my life so far. But my casting is getting fairly advanced. I have not had a problem yet with mine dripping. I have had it freeze up a half a dozen times. But my casting sessions were in 40° weather outside with a wind. But so far I have a lead battery clamp hanging from the handle of my PID controlled 4-20.i learned to heat the nozzle up with a torch and keep a screwdriver handy to turn the top of the arm when the time comes. I also learned to leave my pot full when I turn it off. All ideas I would have had to learn in a lifetime of casting. It has made me have some success an know the why when I didn't. This forum has been invaluable.

[Dave W.]

I'd freeze if trying to cast in 40 degree weather. I tend to have the best luck casting when it is 80 degrees. Because of that I cast in the beginning of summer and in the fall.

[Iron369]

My 20-4 pot drips terribly. Between every single pour it drips. I’ve learned to pour, while holding the mold in one hand I turn the pin a quarter turn, then cut the sprue. If I don’t, the drips will break up and send little fragments of molten lead flying. It’s been like that since I bought it. I even took it apart and bought a new pin. Same thing. I guess some people get all the luck. I’m not one of those people.

[robg]

My 10 lb pot is much less drippy since I cleaned and polished the nozzle etc but I stand my pot in a baking tray to catch any drips and splashes.its only 20 years old .

[Pablo 5959]

I guess I just got lucky. Mine drips but nothing like I see here.
Before I started using range scrap I never had any drips.
I just put a small metal cup under the spout and return the lead back about every 50th pour.
Losing maybe 5 or 10 degrees. Not enough to have to stop casting.

[Froogal]

Fluxing with candle wax every time new lead is added seems to help.

[Mike W1]

My 10 lb pot is much less drippy since I cleaned and polished the nozzle etc but I stand my pot in a baking tray to catch any drips and splashes.its only 20 years old .

I use the 10# pots myself and they'll also drip a bit too. Long ago had a 1/4x20 tpi bolt brazed on so I could put tapped aluminum handles on for a bit of extra weight and not have to grab a screwdriver to give it a twist. For reasons of clearance as I use stacked pots the lower one is shorter. Then I replaced that one with one of cold rolled steel for a bit more weight. Recently I added the lead filled weights to the ears. Seem to help. Also another gentleman suggested bending the tip of the valve rod a bit which was also helpful I believe. I really think the thing that probably was most beneficial may well have been just using beeswax for a flux and clean ingots. Generally speaking a little twist of the rod takes care of things just fine.