Mold probe.

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AJC1

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I see the option on some mold makers for a add on probe. Does anyone get this option and why. I could immagine it may be useful for automation.
 
If you have a PID (which I recommend) you won’t need one. A hot plate will keep your mold at a good operating temp if you need to take a break. Metal coffee can cut down to 5 inches and a slot cut for the handles on the hot plate on medium high for the entire time your lead melts. Flip it sprue plate down while you flux your lead with the coffee can on it. You’re in good operating temp and making good bullets in a few pours. PID and a good rhythm will keep you in that zone a long time.
 
I don't but I would get the option if I were ordering an NOE or similar, and have considered drill my Mihea mold for a thermocouple. Just because it's predrilled for a thermocouple doesn't hurt anything to not use it.

Since molds are much like guns, they each have their likes and dislikes (temp wise for molds). Every now and then while casting, seemingly without reason, you will start casting those perfect bullets. Wouldn't it be nice to know what the mold temp was so you could target that temp next session rather than casting a dozen cycles to find it again, or letting you know you need to speed- up or slow-down your casting pace? Especially useful for preheating your molds on a hotplate. But I'm mostly a knewbie to bullet casting. A trip over to castboolits.com and a little searching will generate more hands-on information.
 
And for the less knowledgeable, a PID is?
It is a box that you plug into the electrical socket then plug your lead pot into that and through a thermocouple in your lead pot keeps you at the same temp by shutting the power on and off.
 
Pelvic Inflammatory Disease.
Either that or A proportional–integral–derivative controller (PID controller or three-term controller) is a control loop mechanism employing feedback that is widely used in industrial control systems and a variety of other applications requiring continuously modulated control.
ie, a temp controller.
 
Mine was cheap, but seems to be a lifetime buy. I only use it for casting rifle bullets when I’m wanting bullets within 3/4 of a grain of each other. And only for plain base bullets as I weigh and run my GC bullets across a piece of sandpaper to get their weights almost exact before I put the GC on.
 
I don't but I would get the option if I were ordering an NOE or similar, and have considered drill my Mihea mold for a thermocouple. Just because it's predrilled for a thermocouple doesn't hurt anything to not use it.

Since molds are much like guns, they each have their likes and dislikes (temp wise for molds). Every now and then while casting, seemingly without reason, you will start casting those perfect bullets. Wouldn't it be nice to know what the mold temp was so you could target that temp next session rather than casting a dozen cycles to find it again, or letting you know you need to speed- up or slow-down your casting pace? Especially useful for preheating your molds on a hotplate. But I'm mostly a knewbie to bullet casting. A trip over to castboolits.com and a little searching will generate more hands-on information.
I do agree that getting a mold in the zone is nice but a heat gun would give you the same data and serve other purposes. Data driven techniques are good I guess I just havent found a need or achieved that level yet.
 
I cast bullets for a long time without knowing my lead temperature or mold temperature. I just adjusted the setting on my melting pot and casting speed until I started getting good bullets. After I got good bullets I just stayed in the zone. Then I bought a thermometer when Midway had one on sale. It mostly just told me what I had already figured out. But it helped. Experience counts for something and sometimes includes some wasted time!

I now have a PID that controls my melting pot and a hot plate to warm my mold. I don't worry about mold temperature. Even if the hotplate does not get the mold hot enough it will be hot enough after the first cast or two.

It was interesting to watch the readout on the PID when I dropped a few sprue's back into the pot. Even a 20# pot will drop a degree or two. Like I said, I already knew this from experience but it was interesting to see just how much effect this had on the molten lead.

Having said all of that, a PID makes casting a little easier. I don't monitor my mold temps but my PID makes keeping my melting pot temps even.

On another note, I have weighed some of my cast bullets and most weighed within the same range that I expect from my Sierra bullets. This was in my pre-PID days.
 
I cast bullets for a long time without knowing my lead temperature or mold temperature. I just adjusted the setting on my melting pot and casting speed until I started getting good bullets. After I got good bullets I just stayed in the zone. Then I bought a thermometer when Midway had one on sale. It mostly just told me what I had already figured out. But it helped. Experience counts for something and sometimes includes some wasted time!

I now have a PID that controls my melting pot and a hot plate to warm my mold. I don't worry about mold temperature. Even if the hotplate does not get the mold hot enough it will be hot enough after the first cast or two.

It was interesting to watch the readout on the PID when I dropped a few sprue's back into the pot. Even a 20# pot will drop a degree or two. Like I said, I already knew this from experience but it was interesting to see just how much effect this had on the molten lead.

Having said all of that, a PID makes casting a little easier. I don't monitor my mold temps but my PID makes keeping my melting pot temps even.

On another note, I have weighed some of my cast bullets and most weighed within the same range that I expect from my Sierra bullets. This was in my pre-PID days.
I'm a believer in pot control. My setting of 7 seems very arbitrary and when my pot starts getting half or below I have to dial it back to a out 6.5. I'm learning her ways for sure but from a data driven approach I would be found lacking.
 
My 30 year old thermometer broke a few weeks ago. I had a few casting sessions without it while waiting for the replacement to arrive, and everything worked just fine. I was awfully happy to get the new one, though.

I've preheated molds with hotplates, heat guns, and by just dipping them into the molten lead for a couple of minutes. It all works, and I've never damaged a mold with any of them. So when I first heard of "drilling for probe" I spent about 30 seconds thinking on it and then decided that life is already complicated enough.
 
Would a IR probe work? No drilling, just point and pull the trigger, read the value. I know from experience that some times they have a problem with shinny surfaces.
I think you may get different results depending on if your brass, cast, or aluminum. My guess is aluminum would be the most difficult
 
I'm a believer in pot control. My setting of 7 seems very arbitrary and when my pot starts getting half or below I have to dial it back to a out 6.5. I'm learning her ways for sure but from a data driven approach I would be found lacking.

Is that with a Lee 20 lbs pot?

I usually start with mine at 7 or 8 and then slowly back off to about 4 or 5 by the time I'm finishing up. I pay attention to how long it takes the sprue to harden and what the bullets look like. If the bullets are all frosty and the sprue stays soft for more than a couple seconds I turn the pot down or back off on the rate I'm filling the mold.

The mold probe would probably be real nice for an automated setup but having a probe attached while casting by hand seems like it would just get in the way. A PID would be handy but they cost more than the Lee pot cost.
 
Is that with a Lee 20 lbs pot?

I usually start with mine at 7 or 8 and then slowly back off to about 4 or 5 by the time I'm finishing up. I pay attention to how long it takes the sprue to harden and what the bullets look like. If the bullets are all frosty and the sprue stays soft for more than a couple seconds I turn the pot down or back off on the rate I'm filling the mold.

The mold probe would probably be real nice for an automated setup but having a probe attached while casting by hand seems like it would just get in the way. A PID would be handy but they cost more than the Lee pot cost.
That's exactly the one. It's in several pictures in the what have you done in the reloading room thread.
 
When I first started I purchased one mold from NOE and had it drilled. Added a BBQ type digital thermometer with a long lead.

I poured a couple pounds using the thermometer and keeping the mold at a fairly tight temp band, and a couple thereafter without the probe.

It was certainly a learning experience whereas the temp does effect weight and finished sizes. While loading and keeping track of the rounds while testing loads, shooting them off a rest, I really didn't notice a great deal of dispersion accuracy wise at 20yds. However stretching that out to 50 was a considerable difference.

Is it worthwhile...IMO the PID and a thermometer in your pot to verify are much better. A good 3, 5, or so count letting the sprue cool and a good alloy work equally as well or better.
 
And for the less knowledgeable, a PID is?

It’s a Proportional-Integral-Derivative control. They can be set, some can actually learn, to maintain temperature very accurately. Where thermostats (on/off) run up to a temperature, shut off, then turn back on when the temp goes below set value, a PID can see a rapid rise approaching set point and taper off addition of heat. This reduces or eliminates over shooting set point temp. They can also sense a slight or great loss of heat and apply more as appropriate. Hysteresis can also be set as well. In short a thermostat has temperature constantly rising or falling around the set point, the PID doesn’t.

Think about driving a car with an either on/off throttle control vs your accelerator pedal you can depress in proportion to requirements encountered.

I first started using them on my smokers.



The wood fired one, on a calm day can maintain set temperature with in a single degree, fluctuating just tenths of a degree.

A friend gave me a bunch of them years ago and I also used one on my casting machine as well.

 
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"Back in the day..." when I was casting I used a home-built thermocycler (tempering box) to keep the molds up to temperature. I got the box and insulating materials from Heath Kits, the heating elements from Sears, and made the monitoring circuit/rheostat using electrical parts from Radio Shack and an article in Popular Electronics. The heating coils were made for a regular cooktop so they got plenty hot even on just 110VAC. The box was just a seam welded steel box with an opening on one end and a hinged "door" to cover it during cycling. I left it open when the mold was in it, of course, but it didn't really make a lot of difference in heat retention. The insulation was like fiberglass but much more dense and not real effective. I burned myself on it pretty regularly. The hot plate and coffee can idea is a good one. Wish I'd thought of it back then. My box was a lot more complicated and kind of heavy.
 
"Back in the day..." when I was casting I used a home-built thermocycler (tempering box) to keep the molds up to temperature. I got the box and insulating materials from Heath Kits, the heating elements from Sears, and made the monitoring circuit/rheostat using electrical parts from Radio Shack and an article in Popular Electronics. The heating coils were made for a regular cooktop so they got plenty hot even on just 110VAC. The box was just a seam welded steel box with an opening on one end and a hinged "door" to cover it during cycling. I left it open when the mold was in it, of course, but it didn't really make a lot of difference in heat retention. The insulation was like fiberglass but much more dense and not real effective. I burned myself on it pretty regularly. The hot plate and coffee can idea is a good one. Wish I'd thought of it back then. My box was a lot more complicated and kind of heavy.
Is just using the top of the pot out of the question, because it works great. I put the mold on top so they both heat up together. May be harder with molds bigger than 2x but that's what I've used so far. I have a 6x I have yet to try....
 
Is just using the top of the pot out of the question, because it works great. I put the mold on top so they both heat up together. May be harder with molds bigger than 2x but that's what I've used so far. I have a 6x I have yet to try....
The rule of life applies here: If it works for you, then it works. Do it. :)

If I had it to do over again I would NOT go to the trouble of building some overly complicated tempering oven to keep my dies warm. I sold that thing for a lot of money - about $100 IIRC, back in 1987 or 88 - along with almost all of my reloading gear. It was a kit built from parts assembled by a teenager that got plugged into an electrical outlet. Lucky not to have burned any of my apartments down.
 
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