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Blackwater
08-27-2012, 07:51 PM
I've long been a dipper, but think I may want a bottom pour now. I'm not impressed with the thermostat on my Lee 20 lb. dip pot, and there have many who've expressed same with their Lee pots of all types. Do the Lyman, Rcbs, etc. have better thermostats?

Also, can one get a better thermostat and install it? If so, where????

Thanks for any help.

runfiverun
08-27-2012, 09:03 PM
p.i.d controller....
or more mass.

500MAG
08-27-2012, 09:10 PM
I have heard that they all have wide fluctuations. I have used a 1000 watt dimmer switch made into a plug that works pretty good but a PID is the way to go.

Frozone
08-27-2012, 09:16 PM
The RCBS , Lyman, and Waage ect. units have pretty good thermostats.

The LEE isn't a true 'thermostat', it works by reading current through it and after a certain amount (an element heats up until it trips) shuts off for a while (until the element cools down and resets.).

Best (and most expensive) solution is a PID controller. The best advantage to aPID on the higher end pots is it'll work on all. you only need one to work multiple pots.
Plus it'll do a sizer heater or a heat treat oven.

AND, BTW, I just happen to build the things ;-)

craig61a
08-27-2012, 09:21 PM
The thermostat on my Lee is just a simple bimetalic strip. I plan on building a small controller that I can use in place of the one on the unit. For under $100 you can put together a temp controller, thermocouple, and relay to control pot temp.

Of course the smaller the pot, and the less mass of the pot the more temp will be lost if you add a quantity of lead. Depending on the output of the heat source temp variations will still be seen.

Hank10
08-27-2012, 09:25 PM
i cast fast so cast at 800 degrees from a RCBS 20 lb. bottom pour. Last week as i was casting I checked it with my thermometer and it was dead on 800 degrees.
I was surprised, I had no idea it was that accurate. I add alloy at regular intervals so the temp stays about the same.
Hank10

HDS
08-28-2012, 03:15 AM
Got a PID for my Lee 4-20 and it's been a superb upgrade. No more fussing with the controls all the time.

11B-101ABN
08-28-2012, 11:25 AM
A quick look at ebay will give you all you want. Item number 110929620310 is a pid controller, WITH a thermocouple, and an ssr (solid state relay), complete package to your door for about $45.00. Wiring it all up is pretty straightforeward, but if you are unsure, any friend that is interested in electronics or electrical could do it for you. Possibly a Ham Radio op, or electronic tech, or a lot of electronic trade schools have "Service Centers" where the students get "hands-on" could possibly get it working for you for a reasonable cost.

Frozone
08-28-2012, 01:05 PM
The PID, SSR combo is the cheapest part of the project!
That thermocouple is a small screwin type.
You have to put those through the pot, that takes extra hardware and they are one to a pot.

Can you make a controller with that kit? yes.
Will it cost you only $45 to do it right? NO.

Heatsink to fit the full sized SSR - ~$12.
Enclosure, if you buy one, and don't mickey mouse a computer power supply case - $10 - $25
Thermocouple plug/jack for a removable thermocouple - ~ $7
Power cord $5
Power switch (if you don't want to just 'pull the plug') - $2
Fuse/holder - $3
Miscellaneous hardware maybe $5 maybe more If you use wire ends - those run a few cents each and add up Fast.

Oh yeah and a thermocouple you can really use - $7 -$12

Now add shipping on all those.

That $120 for a PREWIRED kit is looking pretty good isn't it.

And one thing you don't/can't get with that ebay thing is my 3 lite warning system - priceless ;-)

theperfessor
08-28-2012, 06:58 PM
I built a dual PID controller, there is a sticky in this section about it. Frozone shared a lot of helpful advice with me, and I have a full machine shop to work in. IMHO his price for a pre-wired PID controller is a fair price, especially if you don't have all the tools and skills to be onfident in your work.

I'm very satisfied with my unit, it really works well at controlling my cheap hot plate and my Lyman 20 lb pot. Much better than any thermostat. As I recall I spent about $200 and several days making mine. My BIL built one at about the same time, and he used the miminum size/cost/capability components and assembled it on a piece of plywood or MDF. He spent a lot less time and money (<$40) and got a perfectly satisfactory unit that works well with his Lyman 10 lb pot.

A lot of folks here will help you if you try to build one yourself, only you can decide how much your time is worth.