My (new) Lee pot mods

[dikman]

As I mentioned elsewhere, I have been modding my Lee pot. Hopefully the photos will help.
First thing was to make a new base plate. The aluminium sheet I had wasn't thick enough by itself, so I added a couple of flat steel bars underneath on either side. The support plate for the pot was made from three pieces of flat steel bar welded together and then cut and ground to shape. I figured that having steel in contact with the bottom of the pot would eventually cause rusting, so I cut another piece of ally plate to fit between. The extra holes are to allow for the existing screws on the bottom of the pot, as I didn't want to remove them.
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The support rods are 10mm x 1.5mm thread (because that's what I had. I was originally going to use 1/2" rod, but I don't have a 1/2" tap to thread the base plate!). It took a lot of trial-and-error to get the support plate to fit, as every time I tightened it up gaps would appear at the front. Eventually I realised that the element mounting screws were actually holding the pot at an angle, so I filed about 1/16" from the bottom front of the main tower. This canted it forward enough that the pot now sits pretty flat on the support plate.
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I made a rod to replace the original long support rod. This was only long enough to go from the bottom of the pot and extend about 1/2" at the top. I silver soldered a nut on the bottom of the rod, ground it down to form a head, turned a shoulder on the top bit and ran a 3/16" thread down to hold a bracket for the thermocouple probe.

A mold shelf was made from more ally plate. (I might add a guide later).

Next was an aluminium knob screwed onto the top of the metering rod, so I don't need a screwdriver to adjust it.

Then it was time to try it out, using my spare, untried el-cheapo (REX C100) PID.

It worked well, inasmuch as it heated up very quickly (I didn't have the PID in cct to start with, and it got up to nearly 1,000F before I realised what was happening!!!!).The PID itself worked well and kept it to within 2 degrees of the target temp (725F) once it had settled down - and I hadn't even run the auto mode (mainly 'cos I forgot how to set it (Chinese instructions!)).

As for casting, definitely not as straightforward as the Pro-Melt. The flow rate is trickier to control, and I ended up with lots of "run-off" on the mold and a very poor success rate. I put this down to the rounded shape of the metering rod at the nozzle, and when I adjusted it to try and give a smaller flow the rod didn't always drop back to seal the nozzle and it kept flowing!! If I make a new handle on top from steel, instead of ally, the extra weight, directly over the nozzle may fix this. I'm also wondering how difficult it would be to make a new handle assembly similar to the Pro-Melt's - the extended handle and the pivot at the top of the metering rod are more positive in operation.

All things considered, though, it's not bad. I'd like to make a replacement nozzle and metering rod, with a better shape for controlling the flow, but that will be a last resort! In the meantime, I'll continue to experiment with it.

[propwashp47]

keep at it you will get there

[runfiverun]

if you order enough rcbs parts you'll end up with one eventually.

[seagiant]

if you order enough rcbs parts you'll end up with one eventually.

Hi,
Good mod! No one loves to play with this stuff more than I! I finally saw the light and bought a RCBS Pro-Melt and never looked back! I was lucky as I called the nice lady at RCBS and asked about a "second" and she had one! The only thing I could find was it had a very small dent at the top left corner where someone had dropped it!

[dikman]

if you order enough rcbs parts you'll end up with one eventually.
[smilie=l:

No, the idea is to do it all without spending any more money on it -which I haven't, so far.

Seagiant, I stood the two side-by-side today, and looking more closely at the RCBS handle arrangement it shouldn't be particularly difficult to duplicate it on the Lee. I believe that the RCBS tends to transfer the weight of the handle better to the vertical metering rod, plus it wouldn't be hard to fit a spring to provide additional downward pressure if needed.

First thing is to find a suitable piece of steel for the handle and bend it (I'll probably need the forge to heat it and shape it). The rest of the brackets are pretty simple.
By the way, I fitted a flat shelf to my RCBS for supporting the mold (clamped it to the rear uprights). Much better than the rod support that is provided.

[dikman]

I decided to give the RCBS handle idea a try, as my second attempt with the stock handle (with the addition of an extra steel knob screwed on top of the metering rod) was not exactly inspiring. The feeling I've got is that the rod isn't lined up that well with the nozzle, so when I release it the rod doesn't slide smoothly (and squarely) into the nozzle, particularly when I set it to minimum flow. So it drips and/or doesn't shut off unless I tap it down.

The fitting I made keeps the rod aligned with the nozzle, and the pivot on the left should transfer the weight of the handle vertically down the metering rod (unlike the Lee system, which is applying sideways force as well as down). At least that's my theory. I just have to make the right-hand bracket (to act as a guide and provide adjustment), fit a knob to the end of the handle - I'll make a steel one to provide additional weight - and then we'll see just how clever I am (or not, as the case may be).[smilie=1:
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[dikman]

The end result - it works great!! I can now control the flow to almost a trickle and it has a positive shutoff when I let go of the handle. It did start a very slow drip at one point - a little globule slowly formed, dropped and then another, but I have no idea why that happened as it was casting well before that and was fine after it stopped. I suspect it's to do with the design of the nozzle/rod seat. I cast about 100 .490 balls with about a 10% failure rate, which was mainly due to me trying to find the right rhythm with it.

I feel much happier with the Lee now.
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[blikseme300]

Lee does make some nice starter kits for us to use in building what we need.[smilie=l:

[Petrol & Powder]

Normally I can get along with most mechanical devices with little trouble but my Lee Drip-O-Matic seems to be the exception. The design seems to beg for some type of modification. That "screw head in the metering rod slot" engagement seems to be some type of late Friday afternoon attempt to make it work as cheaply as possible.

[Handloader109]

I added a thumbscrew on mine. Makes it easier to adjust, screwdriver slot just doesn't get it.
No major drips. If I get more than a couple of drops, I run the valve closed and back open to where it was. Stops the drips. Like your valve alteration, But don't really know that it solves the problem any more than anything else. The valve is still the same. RCBS looks nice, but I can toss this pot and buy about 5 more before I spend what the RCBS costs. And minor drips are not a problem to begin with. Oh, I've got less than $50 in my PID Only can buy 4 more Lees.......

[Petrol & Powder]

10-4 on the cost advantage of the Lee ! I'm fairly happy with the device except for the valve assembly. It seems like Lee took a pot designed for a ladle and told the engineers to convert it to a bottom pour as cheaply as possible.....and they did.

[dikman]

Handloader, I don't believe the valve, in itself, is necessarily the problem, rather it's the way the valve rod aligns with the seat (after all, any valve will leak if a bit of grit gets caught in it - even my RCBS did this once). My mod, as per the RCBS design, keeps the valve rod aligned vertically and allows the handle weight to be transferred more effectively to the valve seat. The stock design actually puts sideways pressure onto the valve rod and the subsequent friction in the side of the valve seat can stop the rod from fully closing.

My Lee developed a drip not long after I got it, and adding extra weight to the handle and/or to the top of the valve rod didn't help, particularly as I was trying to use a very slow flow rate. My handle mod allows me to use a slow flow and I've had no troubles with drips since. But it was a lot of work, and I'm sure many will think it's not worth the trouble - I just happen to be one of those people who always look at ways to improve things that I buy :grin:.

[QIDPlb]

I have a Lee , Saeco and RCBS. All needed some form of tweaking to fix a drip issue. Got them used from friends who got tired of them. I'm happy to say they don't drip anymore.

[cdngunner]

One mod I did to my home made pot is to drill a hole in the mold support bracket so that any drips go through the bracket into a small container below.