Finally learned the secret of casting good bullets

[pdgraham]

My neighbor is an electrician..

I had him run a dedicated 20 amp line to my casting station on the back porch..

That made a world of difference...

[mike in co]

most people do not know that voltage changes throughout the day. this causes havoc with welders. you get everything set just right in the am, and after lunch nothing is right.
i have mentioned this before, when casting you need an accurate thermometer...cause the markings on the side of your pot are as inconsistant as the incomming voltage.
consistant temp makes consistant boolits.

mike in co


My neighbor is an electrician..

I had him run a dedicated 20 amp line to my casting station on the back porch..

That made a world of difference...

[mto7464]

finally got a thermometer and boy it taught me alot in about 30 minutes.

[454PB]

I disagree. Yes, I now have an RCBS thermometer and it's fun to play with, but I cast tons of boolits for the last 37 years without one.

When I wired my casting and loading room, I put five dedicated circuits in it, three 120 volt and two 240 volt.

I was in Lowes the other day and glanced at the copper wiring I used when I wired my shop in 2003. I bought 250' rolls of 12-2 W grd. for $18. Now it's $69!

[targetshootr]

I can't get over how much the price of wire keeps going up. But to make up for it, they keep raising the price of gas too.

:castmine:

[mike in co]

you can dissagree all you want...you cannot ignore or change physics.

voltage determines heat( resistance in the element), voltage changes throughout the day in any reasonably populated area...and probably on the outskirts of populated areas.
the npsh( the net positive suction head) is the results of the height of the alloy above the pour port. flow is based on the head, resistance to flow(temp/alloy) and the size of the pour port. the above result in how well the cavity fills. keeping all of this consistant results in consistant boolits.
or one could just cast for 37 years and never know why one had variations in what was cast. not a big deal in some pistol boolits...but try doing match grade rifle boolits with out the proper tools.

if you always cast at the same time of the day, on the same days(sat/sun)....you may never see the difference. me, i cast any time day and night, any day of the week.

mike in co

[MT Gianni]

It also depends on what is on your transformer and who you share it with. Gianni

[randyrat]

It's "The Man" messin with us. They don't want us to make too good of bullets so they figured out a way with electicity:twisted:, I'm votin for change.

[Bret4207]

Another reason to stick with a ladle.

[454PB]

Yes, Mike. I worked in power plants and substations for 37 years as well, and I know how electrically produced heat works. If you have more than a 4% or 5% voltage fluctuation in your house or shop, it's your power companies fault. There are damn few thermostats that can regulate within 5% at 700 degrees.

[John Boy]

There are damn few thermostats that can regulate within 5% at 700 degrees.
Cen-Tech Digital Thermometer - Model 92242 that was discussed here a couple of years back. Was sold by Harbor Freight in their stores ... about 40 bucks

Accuracy: plus or minus (0.5% reading 2* F) ... 32 - 2000* F

Works like a charm!

[AZ-Stew]

Quotes:

Quote:
There are damn few thermostats that can regulate within 5% at 700 degrees.

Quote:
Cen-Tech Digital Thermometer - Model 92242 that was discussed here a couple of years back. Was sold by Harbor Freight in their stores ... about 40 bucks

Accuracy: plus or minus (0.5% reading 2* F) ... 32 - 2000* F

Works like a charm!

******************

John Boy,

You're describing a thermoMETER, 454PB was talking about a thermoSTAT. A thermoMETER measures temperature, a thermoSTAT is a temperature controller. As 454PB said, they're electro-mechanical devices that aren't very precise. There are electronic devices that can provied precise temperature control, but none of the casting pot manufacturers are willing to add one to their product because of the cost.

Regards,

Stew

[John Boy]

454PB was talking about a thermoSTAT ...a thermoSTAT is a temperature controller. ...[smilie=b:

[Boomer Mikey]

If you have more than 10% voltage fluctuation something is wrong. Your thermostat on a good pot will compensate for voltage fluctuation automatically anyway... it works on temperature not voltage,

I've been using a thermometer in the pot for over 20 years and I have noticed that my Lee 20-4 pot's thermostat isn't very good sometimes. On the other hand, my RCBS pot does a great job, and my Lyman 20# pot's thermostat quit working after 20+ years (replaced it with the Lee) It wouldn't go above 700 degrees anymore.

It's still a good idea to have a dedicated circuit for the casting bench though.

Boomer :Fire:

[38 Super Auto]

So I have spent years learning about Brinell hardness, slugging and proper sizing diameter, antimony for hardness, tin content for castability, high temp lube hydraulic performance, cavity and sprue venting, tin depleted monotype, zinc contamination, arsenic doping levels, mold lapping with toothpaste, wrinkled noses, proper fluxing for alloy reduction and gettering and now I need to start worrying about line voltage variations?

:groner:

[Lee W]

Thermostats do not care about the incoming voltage. They are just switches.
I know the RCBS thermostat is accurate to 6% of scale, or +- 30 F.

I went to a digital controller, +- 5 F.

[Down South]

I notice that my RCBS Pro Melt varies somewhat too. Sometimes as much as 50 deg. I keep a thermometer in the pot at all times while casting and keep an eye on it.
Many times in a casting session I become the thermostat trying to regulate heat. And no I don't throw my sprues back in till I'm ready to load the pot again.

[mike in co]

Thermostats do not care about the incoming voltage. They are just switches.
I know the RCBS thermostat is accurate to 6% of scale, or +- 30 F.

I went to a digital controller, +- 5 F.

lee....can you tell us how this was done ? what part numbers ?

thanks
mike

[BruceB]

Everyone ends-up somewhere in this casting hobby, with methods and opinions formed by their own experience and also by the input of other people who have in turn formed their own way of "doing it".

In my particular way of casting, now extended past the forty-year mark, I don't own, use or need a thermometer. The thermostat on the RCBS Pro-Melt suffices for MY casting. After diligent experimentation with using two or more moulds at a time, and I MEAN that word "diligent", I've found that using more than one mould costs me time and reduces the production rate.

I also re-melt sprues during the course of a casting session, and I do NOT stop casting to wait for the pot to come back up in temperature.

These are a few of the heresies I commit at my bench. For the full story, go to "Homepage" on the toolbar up top on this page, and then click on "Members' Articles" in the left-hand column. Kindly read the article "Speedcasting" with an open mind, because it's a bit different from some procedures. Many casters here have at least tried it, and quite a few have adopted the routine completely.

It just might be worth your while.

[WilliamDahl]

These are a few of the heresies I commit at my bench. For the full story, go to "Homepage" on the toolbar up top on this page, and then click on "Members' Articles" in the left-hand column.

I don't think that your article survived the web forum software "upgrade" awhile back.

[Mal Paso]

A PID controller isn't affected by voltage. Unless it goes so low the pot won't heat. I think the controller will operate down to 24 volts.

[RoyEllis]

I don't think that your article survived the web forum software "upgrade" awhile back.

It did, look in the "Classics and Stickies" for "BruceB's Speedcasting" and you'll find it.:coffeecom

[hickfu]

:groner: maybe that is why I had such a hard time on my last casting session.... I had a fan and the hot plate plugged into the same outlet as my pot and I was noticing that every time the pot or the hot plate kicked on the fan would slow down.....


Doc

[tomme boy]

They are controlled by a RTD or thermocouple and a potentiometer.

[tyeo098]

If you get frostys, turn it down, if they cool on the sprue before going in the mould, turn it up.

I dont need no stinkin thermo-meter

[GOPHER SLAYER]

I sold a perfectly good refrigerater once because we kept loosing expensive meat through spoilage. We bought a new one and it started doing the same thing. A friend told me to check the voltage supply to the house and I did. I was only getting 90 volts into the house. I called Edison and they sent a man out but he didn't talk to anyone in the house and he didn't fix the problem. I complained again so they sent out another man who changed the connectors on the pole and the house, came to the house, checked the voltage and voila, 120 volts. The new refrigerator was a pale shodow of the one I sold.

[huntrick64]

OK, not real sure how this thread from 2008 got resurrected, but it is timely. I can't comment on my electricity, but I can comment on how the variation on alloy temp affects final bullet weight. I have been casting my 535 grain money boolits from my bottom pour Lyman pot with a new BACO mold and no thermostat. With 50/50 alloy I would get weights similar to below:

531 grains - 1-2 boolits
532 grains - 4-8 boolits
533 grains - 20 or so boolits
534 grains - 30 or so boolits
535 grains - 20 or so boolits
536 grains -10-15 boolits
537 grains - 1-2 boolits

Since my tolerance for these boolits is + or - 1/2 grain (for a one grain top to bottom variance) I was having way too many rejects.
I added a thermometer and the temperature would vary about 50 - 60 degrees from top to bottom. So, I would only cast boolits when the temp was between 750 degrees and 775 degrees. If it was out of that range I would keep my mold hot on the hotplate and wait for the alloy temp to get back in that temp range.

Big difference

531 grains - 0 boolits
532 grains - 1-2 boolits
533 grains - 15 + boolits
534 grains - 60 or so boolits
535 grains - 15 + boolits
536 grains -1-2 boolits
537 grains - 0 boolits

Since I can't afford (time or money) to build a PID I decided to fire up my propane-powered smelting pot and put 40 lbs of alloy in it. It was surprisingly easy to keep the temp from 550 degrees to 560 degrees!!! I was amazed at the difference now.

531 grains - 0 boolits
532 grains - 0 boolits
533 grains - 7 boolits
534 grains - 82 boolits
535 grains - 11 boolits
536 grains - 0 boolits
537 grains - 0 boolits

I need at PID before winter!!!