Had to REMODEL the CASTING area for a PID...

[OS OK]

Thanks be to SSGOldfart...he and I did a 'horse-trade' and I ended up with a new used PID pot controller.
I did several YouTube instructional videos on programming, then had to add a shelf to shuffle things around a bit...then, I threw in a batch of 2:1 isotope and COWW + 1.5 oz. of Sn and got to casting.

What a difference. I don't miss trying to keep the pot temperature trimmed manually...that was a pain. Now it's about concentrating on casting.

Don't know why I waited so long to find one of these units!

Attachment 206228

[daloper]

Looks good. I put together a PID but have not had the time to set it up and try it. I have a lot of cleaning to do in my casting area to get ready.

[ioon44]

I wish I had got a PID sooner, it sure makes the casting process run smoother and with more uniform temp the mold doesn't over heat.

[LenH]

I got a kit from he who must not be named about 4 years ago, not sure he is around anymore as his website is no longer there. But it has made a difference in everything I use
it for from casting to running an electric smoker to a powder coat oven. I do have separate probes for each task and keep extras on hand.

[dragon813gt]

I got a kit from he who must not be named about 4 years ago, not sure he is around anymore as his website is no longer there.

He's active on a few other forums. I have trouble keeping track of time anymore. So I could have seen him posting a year ago and think it was yesterday

[OS OK]

I thought I'd be a 'slick willy' and install the thermocouple between the bottom of the pot and the enclosure. You can just see the end of it sticking out on the right of the pot.
That causes a 35*F. temperature differential where the pot is actually hotter in the melt. I didn't worry about that and set the SV (set value) to 690*F. and got 725*F. in the pot...all was good for the first 2/3'rds of the pot as the PID did very well tracking and only overshooting by 6 or so degrees.
Then I noticed the swings on overshoot went to around 40-45*F. when I was casting the last 1/3~1/4 of the pot...'Not So Good'.
I just pulled the thermocouple out of there and placed it directly in the Pb..."Aaah, much better, reset the pot SV to 720*F. and all was well."

I think I'll just keep it in the melt from now on.

[Walter Laich]

I love mine

think the problem is 'old way' is good enough for caster and unless he sees first hand PID in operation is happy with what he has
sorta like, "In land of the blind the one-eyed man is king . . . till a two-eyed man shows up (armed to the teeth)"

[runfiverun]

all that to keep a lee settled in...
you could use mass to do the same thing.

[OS OK]

I'm not so sure I get what your saying R5R...

I can tell you this from yesterdays first run though. At around 3/4's pot full I started noticing that dumping just 4 or 5 sprue cuts back into the melt, it would drop the temperature around 24~26*F. within about 8 seconds of it hitting the melt. Heat from throughout the pot would rush into the colder sprue cuts immediately.

Notice the Dillon thermometer in the pot...at the same time it would show almost a 10*F. swing very slowly...in fact, by the time the Dillon thermometer registered fully 10*F. lower the PID was showing the melt on it's way back up towards the SV (set value).

Until using this PID I never had any idea how the pot temperature would swing so quickly. As the pot got lower and lower I had to drop the sprue cuts every 2'nd cut to stop the wild swings and then also to stop the pot over running the SV (setpoint value)...due to the lack of mass when the pot is low because the AT (auto tune) algorithm still reacts to a full mass in the pot.
None of this is a problem...it's just an observation of temperature that has never been apparent using the slower reacting Dillon thermometer.

I think it explains the spigot freezing suddenly when casting at lower temperatures too.

[DerekP Houston]

I run a pid on my rcbs promelt as well. It's nice to just flick the switch and have everything come to the proper temp with no fiddling.

[dikman]

All looks very neat and tidy, OS.

I have PID's on the RCBS, Lee and my coating toaster oven. Wouldn't be without them.

[OS OK]

Grrrrrr! That dang toaster convection Chineese lying oven is NEXT !

[dikman]

[Grmps]

I've had good with Hamilton Beach 31331 Convection Toaster Oven
and the $20 Oster Convection Toaster Oven (can do 16 # at a time) I got @ Goodwill

[OS OK]

Well Grmps...like a dufuss I went out and bought a new convection oven back when I started PC'ing. Went to K-Mart (first mistake) and bought the cheap analogue controlled unit (second mistake) instead of buying the more expensive and slightly larger digital controlled one (third mistake).

I thought (fourth mistake) the cheaper unit would suffice and it has...it's just been a pain going through the efforts of finding the right auxiliary thermometer and having to use paint pens to mark the temp. knob to the correct setting...and keeping it there. The slightest touch will rotate that knob the width of the pen mark and it's not noticeable unless you really look closely, then the temp. can be off significantly.

Now that PC'ing is so much used here it's down to replacing the oven with a digital or building a dedicated PID for it...I shoulda learned decades ago that cheap is cheap and has side effects down the road! Did I mention that I was a dufuss on this call?

[lightman]

Nice looking area you have there, OS!

[HATCH]

Good looking setup.
I have noticed over the years the "swing" when you put the sprues back in the pot get larger with the less lead you have in the pot.

On my master caster, I put another ingot in (5lb) as soon as there is space in the pot for it.
That way I can keep casting.
If I wait until the lead level is at the point I have to stop and then had a few ingots in, I end up with spout freeze and have to wait for the lead to get back up to pouring temp.

PID's are inexpensive now and there is no reason not to have one on your pot.

[OS OK]

Ha! . . . HATCH, I saw you commented here on the 'latest post' page and thought..."What the heck have I done now?" . . .

I am amazed at the temp swings. That digital thermometer reads it almost instantly. No matter which analogue thermometer used, they can't respond quick enough to give you any real idea of what's happening in there. To get some idea...try stirring the pot with an aluminum utensil of some sort, see how quickly you turn it loose.

I can see why the PID overshoots to a greater degree as the pot empties...it's PID values are set generally with a full or near full pot, so...as it tries to regulate an emptying pot it is constantly applying too much muscle...(as best as I can put it in layman's terms)...the PID cannot know the level of the pot unless it could compare temp swing variables to those of a known 'set' in a pot that is at different levels...then there would be a way for the PID to modify it's values.

Ah...but it's no big deal really, you can just keep the pot full if that works for your needs...it's just that when you blend a pot say for low pressure/velocity HP's, I try to use the entire pot-full to get the desired amount of casts. Using all the Pb is where the temp. swings comes back into play and so far I think it gets pretty wild at around 1/3~1/4 pot full. The best I can manage to minimize this is to put the sprue cuts back into the pot with each cut when the pot is running out.

[6bg6ga]

When you get into it a little more you will have a second pot that is there simply to re-melt the sprew and the new ingots. Once these are melted in this pot they can be transfered into the main pot with the secondary pot once again melting sprew and new ingots.

[OS OK]

When you get into it a little more you will have a second pot that is there simply to re-melt the sprew and the new ingots. Once these are melted in this pot they can be transfered into the main pot with the secondary pot once again melting sprew and new ingots.

Yeah...saw a picture of a guys pots mounted over each other to do exactly this...prolly works pretty good.

Me? Naah....thanks, I'll stay a 'rank amateur!'