Marshall Reloading - Casting Pot

This is a casting pot I have been working on and off for a while...actually more off than on, but that's how a lot of projects go at times. The main chamber is a 6" piece of pipe 4" long with a ceramic heater off McMaster around it for heating. The main pot is controlled with a probe style TC mounted under neath the bottom plate so it only contacts the lead. I wanted it to read the lead temperature more than an area around the heater. That is also why I went with the ceramic heater so it could handle the overshot when it starts up sense the sensor is away from the heater.

The valve is a 1/4 turn valve so that crud in the valve will be cut off and will not be able to float up the valve and hold it open.

http://www.youtube.com/watch?v=rs0iIF7Tqfw

I'll type more up later, just wanted to beat the time out function and I need to go to work now.

looks good! so if im followin ya right the square pot is to drop sprue into without makin a mess?

That's the theory so far....I hope to be testing this out in the next couple of weekends if the weather is okay.

Today at 11:04 AM






Relays and Relay Base

Automation Direct –

8 Pin Set Up as 750-2C-120A Relay and 750-2C-SKT Base

Or 11 Pin Set Up as 750-3C-120A Relay and 750-3C-SKT Base (I used 11's because I had that on hand, but really any relay can be used that will handle the amps)



I worked in an Industrial setting at a heater manufacturer for years, and a lot of the processes to build them use heaters. If standard relays can work for 50+ hours a week for years on end it should be okay for home use. Solid state relays can be used, but all you will really know is that you don’t hear a clicking sound as they won’t make the system run any different.



CD101 Controllers off of Ebay

These do not come with good instructions or set up for reading in degrees F. The controllers are not that bad to set up once you know how, really the P, I, D, Ar settings to do not need to be done as the self tune will handle this itself. Assuming you have a brand new controller you need to set the LCK = 1000....then you can get into the locked features and make the changes as shown below in the second section. The SL2 is how you set it up for degrees F (0001) or oyu can leave it as 0000 for C. SL10 = 1000 will enable the Self tune mode. Then in the first section you can set the STU as shown below to make it self tuning......then run it at lower temps so it can learn before shooting it to the temp you need. Slowly keep setting the temp higher and higher, 180, 360, 500, or whatever you feel comfortable with to make sure it's doing it right.



Press Set and make sure you have the following settings:

Al1 = 0050
ATU = 0000
STU = 0001
P = 00308 (8 on top melter)
I = 0240 (7 on top melter)
D = 0060 (2 on top melter)
Ar = 0100
T = 0020
Pb = 0000
LCK = 1000




Not with the lock to 1000 you can press Set and the button next to it to get into the other menu:

Press Set and ? and make sure you have the following settings:

COD = 0000
SL1 = 0000
SL2 = 0001
SL3 = 0000
SL4 = 0001
SL5 = 0000
SL6 = 0001
SL7 = 0000
SL8 = 0000
SL9 = 0000
SL10 = 1000
SL11 = 0000



Misc Parts from Radio Shack

Fuse Holder = Screw-Cap Panel-Mount Fuse Holder Model: 270-364 Catalog #: 270-364

Light = 120-Volt Neon Red Jumbo Lamp Assembly Model: 272-710 Catalog #: 272-710

Switch = Toggle Switch with On/Off Label Plate Model: 275-602 Catalog #: 275-602





Heaters

I bought a ceramic band heater off McMaster that isn’t listed on the website anymore, really any 6” band heater will work for the pipe. The gap will be a little larger since the pipe OD is 6.625”, but this will allow an off the shelf heater to be used. Mica heaters are not bad, they are actually what I started designing first. The difference between a mica heater and a ceramic heater is the watt density’s that the can handle and the maximum temperature they can handle. So if you have the extra money you can get the ceramic and know that you’re using a smaller percentage of it’s allowable maximum heat range. The ceramic will give you a little more time to shut things down if you notice the heater is running away from you, but that will be the only different in this heating situation. The mica heater will be thinner than the ceramic heater.



If you buy a mica heater, or really any heater for that matter installation can play a big part of how long the heater will last. On mica or ceramic heaters I like to tap them with a soft faced mallet as they heat up and also adjust the clamp and check it the first couple of runs. The mallet will help to form the heater to your piece of pipe after the factory rolled it to approximately the correct OD on a rolling machine. Adjusting the clamp will make sure you have good contact between the heater and the pipe. Just don’t use a rubber mallet on it too hard or when it’s super hot.

This unit has a 1200W heater on it (120V).



Main Pot Thermocouple

An Omega CF-000-K-4-60-1 was installed in the pot since I already had that one on hand, but if I had to order a new one I think I would get the CF-000-K-2-60-1 since that has a 2” long probe where the version on the pot has a 4” long probe. You could order a different end terminal style as well base on how you are wiring it up, but I order the



Side Piece Thermocouple

An Omega 5TC-GG-K-20-72 was installed again since I had it already on had, a far cheaper replacement would be any type K thermocouple with glass braided wire insulation off ebay or any other source that’s selling thermocouples separately. Even just type K thermocouple wire can be used and then strip and twist one end together really hard to make the thermocouple joint.



Control Box

The control box is actually an electric box that I bought at Lowes. I can’t find it on their website, but it was on the bottom shelf when I bought it and has a seal on lid and a nice seal with the box. I also was able to buy the electrical clamps at Lowes just for regular outlet boxes to use with this box.



Wiring

I used some flexible wiring with this unit that I had saved from various other machine tear downs or from the trash at various places. The small heater uses the electrical cord I saved off the vacuum we were throwing away at one point in time. Internal wiring was done with some wire I bought at Radio Shack and also wiring I had already in one of my stashes at home.

a few things need cleaned up in the post above, but I can't loss it from the time out function now! I will clean it up more this weekend and next week.

Here are some pictures of the box taken off the cart and the pot taken off the cart so you can see what the electrical terminals look like.

Electrical box and casting pot with extra relays and other parts shown.
Attachment 86361

Electrical box picture
Attachment 86362

Another electrical box picture
Attachment 86363


Main heater location for electrical hook up, the thermocouple for this heater screws in on the bottom of the pot. It is a probe style thermocouple.
Attachment 86364


Upper (Scrap) heater location for electrical hookup, I just put the thermocouple under the heater as temp isn't critical here.
Attachment 86365

Ground Wire attachment location
Attachment 86366

Second picture showing ground attachment location
Attachment 86367

Will you insulate the outside? Could you elaborate on the bottom pour mechanism? Are you going to stand or sit while casting? With the remelt tray it looks like you would need to be standing to be able to cut the sprue into the tray.

It looks awesome. I would imagine you could just throw a few handfuls of sprues in the remelt chamber at a time and wait for them to melt, rather than cutting the sprues over the remelt chamber, if so desired. I get the whole point of the remelt section. My PID controlled lee 20 pound pot drops quite a bit in temp when I drop in a couple pounds of sprues. I cut and drop the sprues over a metal drywall mud tray. My pot sits a bit higher, on some heavy wood blocks, so I can see the spout and mold better. The remelt tray should eliminate any noticeable difference in temp once the liquid lead gets to the main pot. It can take a few minutes for my 20 pound pot to get back to temp.

I am also interested in how the valve works. I thought about making my own pot in the past and wondered what might work better than the lee spout.

Here's a drawing for the valve, hopefully it attached. You can also use this same valve on a smelting pot, just modify lengths or holes as you want too.

I was really planning on using it sitting down and would probably end up throwing the cut offs into the top by hand every so often as I don't know how easy I could cut off into it. Actually I am preparing to move this spring and am really trying to document this pot so I can rebuild it when I need too. Between the moving and running after a little one I haven't been shooting lately and don't really have time for it very much.

Neat ideas and the pot looks great.

Thanks