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Full.Lead.Taco
I talked to Al and he mentioned he was wanting to make a Digital PID for casting and or powder coating. He wanted me to post on the forums to see if there was any interest:
NOE has started looking at possibly making our own lead pot and while it is too early to say too much about that, we do want to talk about an off-shoot of that project. While doing preliminary design work on the pot we decided it had to be PID controlled from the outset so we sat down with an electrical engineer and designed a PID controller to use with our new lead pot.
We did a number of things to help make it simple, easy to use, easy to maintain, and upgradable.
First off, the design uses a standard computer power cord (C13 style plug). This means wherever you are in the world changing to the appropriate power cable shouldn’t be a problem.
Second, we are looking at making two versions one using 120V and the other using 240V so the units will be usable worldwide.
Third, we are using a mechanical switch (Contactor) as solid state relays are not recommended for the currents most melting pots require. That switch is a standard HVAC part so if it wears out, it can be easily and inexpensively replaced at any HVAC supply store.
Fourth, we used a standard K-type thermocouple probe which allows easy replacement via a socket on the unit face rather than being hard-wired. This allows users to pick a probe length anywhere from 4 to 14 inches depending on pot size.
The unit is fused for 15A at 120V or 30A at 240V to work with most conventional house circuits.
Both the hot and return lead are switched for an added safety margin.
Temperatures can be set between 50F and 932F (10 and 500 C) and can go as high as 1200 F (650C) with a probe change.
The unit is roughly 8 x 5 x 5 inches ( 20x12x12cm) and will come with a 20 Amp rated 120V or 240V outlet depending on the model ordered.
We are looking at a price point around $200 USD and hope to be ready to ship early next year.We are interested in your feedback and suggestions and hope to have some photos of our prototypes up soon.
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davidreiss
Hugh Kuhns
Mike B.
clarishyett
I alway buy something six months before the new and improved model comes out, it’s a habit. I was looking for this, a complete package that was simply plug-in.
I bought two new RCBS Pro-Melt II pots, one for Schuetzen (20:1 alloy) and one for CBA Military and Production (Linotype). I’ve gone to ladle casting for better quality.
The ease of setting the temperature with these pots Ois good. The long wait to shut off while protecting the internal thermostat is not good.
tomacheson
I’ve had a couple Lee small pots and one Lyman 20-pound pot. That pot died. I replaced it with a 40-pound capacity pot. Master Engineering? Having a larger capacity and batch of alloy has really been helpful over the years. It is ladle only, which is a Rowell 1-pound ladle. An integral PID should be included in the design.
All
You are most probably going to have to figure out how to defeat and or remove the PID controller that a lead Pot or a PC coating Baking Oven already has.
So that your NOE PID controller design can work uninterrupted & without tending to fight or compete with the other controller that is already there in the devices that you already have…
If you are interested please read a engineering explanation of the effects that multiple PIDs have on each other…
https://www.controleng.com/articles/not-all-pid-controllers-are-the-same/
Just thought that I should say something… A single PID is good … However the presence of a second PID controller in the loop may not necessarily tend to be such a good idea…
It most probably should be a single integrated system or have added a system or set of instructions on how to defeat the controller that is already there…
Now a simple pot with no real PID built in … might be the cats meow in this instance…
Don’t get me wrong… it is a good idea… One might just have to attempt to think outside of the box as to the presence of a second PID controllers presence might do to the equation…
Your call on how to proceed on this subject…
Take Care, & Stay Safe…
SwedeNelson
We talked with the engineer last night and ordered some parts for alarm circuits and also a couple of high current SSRs just to test with. If the feedback is some think an SSR will perform better, let’s test both and take whichever wins. In asking, the engineer thinks heat will be an issue for the SSR and the 2nd engineer, thinks the mechanical may indeed require that the control be less precise to keep from oscillating the contactor. This is why we ask for feedback, so we are now looking at two versions of the controller one with the mechanical contactor and one with an SSR. We are keeping the safety feature of using a dual channel relay so all voltage will be cut regardless of mis-wired outlets.
We are concentrating on the PID first and hope to move on to a lead pot next.
My thoughts are like others, a bigger pot (30Lb or 40Lb) is in order.One step forward….. but it should help insure we get the best product to market.
With a PID potentially being developed first, It seems to me that the type of pot would generally be up to the individual incorporating said PID into the setup that most probably is already on hand…
In the for what it is worth department … attached below is a link to another potential & similar source that seems to show what potentially is an end product in the future…
Thus the end product design is a compilation of what one wishes to create that is closest to one individuals conception of an end product…
In that end here is a similar endeavor description of what can be done … If one sets ones mind to it…
Each can take what pieces that are being developed and assemble what is nearest & dearest to ones own ideal.
In this article it shows what can be potentially be developed in one sense of the word.
By making the PID separate the potential issue of the adjacent heat of the lead pot being a bottom pour or a ladle version can be adapted as the end user wishes to produce what is in the end users eye the best that one can imagine for ones own application.
http://www.lasc.us/DualPIDTempControl.htm
The pictures at the end of the article tend to show one potential application that one end user has come up with.
It is simply one individuals conception of one might be obtained … Please do not think that this is the only end product available or the end conceptual idea end product…
It is simply one potential end as far as that individual is concerned…
Yours might tend to be vastly different…
Thus it is your call on how you want to proceed…
Take Care, & Stay Safe…
matthewtroiano
I like the one in the link having the ability to control 2 loads. With that being 180 in parts that would be hard to produce and make money off of and would make me want to DIY it. Alarm features would be useless to me for pot temp, because if I am casting I am casting and watching the water boil if you will.
The thing with DIY is either pay a lot for a good enclosure or like I have scrounged up an old PC power supply and that’s ugly. That PSU also has a built in fan and holes for cooling. Will the one you are creating have a cooling fan integrated?
I have one suggestion that might be of some use to others is a place for a temp probe for the mold its self. That having a too cold too hot digital read out with an alarm would be nice I think.
With two PIDS, in the build, one could be setup for the lead pot, & a perhaps second separate one for a powder coat baking oven.. with the appropriate temperature probes for each particular application… ‘
They don’t particularly have to be in one cabinet or enclosure… The article was just one visual sample to look at and what one individual thought… as to what might be needed…
As I have said previously the end build composition is technically wide open for each to produce what for each is nearest & dearest in ones viewing eye… The real issue will be to see what one comes up with that one can adapt for ones own purpose…
NOE offers an option for all its probes to click yes to drill the probe hole when you order an NOE mould on all of its orders … One can avail ones self of the option at the time of the order…
Most every one else in the mould market does not do this… so one will have to carefully setup to drill at least two holes in the non NOE moulds for that particular probe… if you wish to mount a temperature probe on each and every mould. (the second hole needs to be tapped for the set screw to hold the temp probe inside the mould while in use…
I tend to doubt that if one wanted to have the mould drilled & setup for a temperature probe that one could find an outside source to get it done professionally for less than three dollars per mould … Plus a second tapped hole for a set screw to hold the probe in place…
Take Care, & Stay Safe…
Simply that NOE appears to offer what no one else in the industry does… a drilled thermal probe hole that is already drilled into the mould as a potential mould order option, at the time of the mould order.
What other mould manufacturer offers that as a standard option … if one wishes to mount a thermal probe to correctly monitor the moulds temperature?
Any kind of an externally attachable probe block … that could be attached to the mould in some form or shape would also tend to have to basically match the type of material that the mould is made of …
Otherwise the rate of thermal change on the external block temperature holding the thermal probe would being of a different material would tend to change temperature at a different thermal rate than the actual mould itself.
This would tend to give one a false reading on the moulds actual temperature …
For instance most everyone basically knows that Brass tends to hold the heat longer than Aluminum… in addition … steel has a different rate of thermal change in addition to aluminum & brass…
Plus the attached block could quite possibly tend to get in the way of filling the mould if one is not careful, & thus affect the refill rate of said mould with an external block being attached to the mould itself…
Besides coming up with a suitable spot to positively mount the external block so as to not to affect the fill rate where one could attach to the mould in the first place, for all the different types of mould blocks out there in the field.
Changing the fill rate at which a mould is filled thus also tends to change the temperature of the mould itself… as one is reheating said mould with each refill of the mould cavities.
One can experience that by simply changing the rate at which a mould that you might have, By changing the rate at which said mould is filled and looking at the cast product for frosting or not …
Too slow a fill rate and the cast product tends to get folds in it as the lead alloy cools before the mould is filled… as the mould is now too cold to produce good product.
Too fast, & the cast product tends to begin to frost up, & begin to pull away from the mould body itself … causing both a frosted surface, & more importantly differences in the end products shape & appearance as the lead alloy can shrink away from the excess heat emanating from the mould body itself …
Take Care, & Stay Safe…
davidreiss
Hugh Kuhns
Mike B.
clarishyett
tomacheson
SwedeNelson
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