The lowly student comes to his Masters

[kbstenberg]

This lowly student has been pondering the ways to keep a mold at the proper temperature. I saw the thread by NOE on his temperature reading device an have been wondering about the opinions users. Good - Bad - or indifferent.
I would like to hear from the more experienced casters as to some the problems mite come up.
One concern I thought of is that where the hole is drilled for the probe would cause a cold spot in the mold when a person is casting without the probe in place. Or that even with the probe in place there could possibly be a cold spot on the mold
I do think the temp reading device would be a good teacher for keeping the mold at a constant temp. if a person keeps track of all the little things an how they affect the mold temperature.
Kevin

[btroj]

Mould temp can have a difference in bullet quality and consistency. First you must ask yourself what YOUR needs are. For plinking or short range hunting consistency is not a big issue. For BPCR it can be a huge factor. I don't worry it as I am not in need of cutting edge accuracy. This does not mean I want crappy bullets, it means I don't need them to weigh within a fraction of a grain of each other.
I don't think the probe hole would make a big difference in mould heating. It is a reasonably small hole and far enough away from the cavities to ensure it has minimal effect.

I judge mould temp by seeing how long it takes the sprue to harden. I don't time per say but judge it by eye. When it gets too got I cool it by dunking the end very quickly in water. A damp rag works well too.

I would be interested to know if anyone has done testing to show how narrow a temp range needs to be held to stay consistent in weight and diameter. Do we have a 10 degree window? 25 degrees? 50? Would be interesting to know.

I like to keep my hobby simple. I don't have any thermometers, no hardness tester, I don't weight alloys precisely. Somehow I have had success for 20 years shooting cast. Some of this is goi g to end up being a factor of YOUR need to fiddle fart around with things. If you like to tinker and worry, by all means go for it. I don't.

Brad

[peerlesscowboy]

The time it takes for the sprue to frost over and the appearance of the dropped bullets tells me if the mould is at the proper temperature.

John C. Saubak

[btroj]

The time it takes for the sprue to frost over and the appearance of the dropped bullets tells me if the mould is at the proper temperature.

John C. Saubak

Exactly

[dromia]

Thoughtfull experience will enable you to gauge the temperature consistency but not necessarlily the temperature.

A thermometer will give you a temperature and thus allow you to monitor temperature and temperature consistency very well.

I use the thermometer as an extra control when my boolit quality control is critical, mainly for long range HV boolits. For most of my shooting I just QC the boolits after casting by visual, weight and dimension inspections and monitor temp consistency by watching the moulds I do this because I'm after a volume cast and want to spend my pot time dropping boolits.

For short range stuff I just go with experience.

I like having a thermometer and find usefull even although I don't use it all the time.

Each to his own and its the way that gives you the results you want, the way you want to get them that is the "correct" way. :D

[HeavyMetal]

saw a guy once that actually put a temp guage into the mold Permanently!

Cool idea, ungainly to work with!

If I was shooting long range BPCR yes I would come up with a way to add as much consistancy to my casting as possible. It would be one of the new non contact infared gauges that you point and shoot for a reading.

I have one and it can be very interesting to use during a session of casting but will not work on the alloy itself because of reflection issues.

However I have a reliable system for reading alloy temp so don't need it for that.

Harbor freight has, or had , a sale on these for about 25 bucks and I think I would tape the trigger down on one and then shove the mold in front of it every time to see what it read!

Some of these work this way and some need to have the trigger released to give the current reading. Either way once you had a usable mount made up checking mold temp without drilling and mounting a sensor or guage would be very easy!

For every day casting alloy temp and very smooth rythem get it done as well as anything else!

Inspection time culls the visable trash from the user boolits, and, if I need to shoot for "bragging rights", I pull out the electronic scale and weigh boolits seperating them into a series of weight ranges.

Generally I keep these boolits grouped into a half grain range but the real reason to weigh boolits is to get the "oddball" weights that cause flyers sorted out of the mix!

If you try this it can be an eye openng experience! I cast very consistantly but was amazed that I had several ( if I cast 1000 45 boolits I'll get a dozen or so way out of the base range by like 6 to 10 grains) that are way to light or to heavy.

These are the reasons I think we see that odd "flyer" we can't explain ( that's my excuse Patent Pending LOL) when load testing or plinkin with the bud's!

Food for thought.

[stubshaft]

I judge my boolits by how the sprue cutter shears off the base and the overall appearance of the boolit. I cast a large puddle so that there is adequate metal for drawdown and in some cases the base has frozen before the puddle even frosts over. Once I get the cadence going I usually count to determine the time before opening the cutter with my gloved hand.

[mold maker]

The mold thermometer that is tethered by a wire would (to me) be a serious hindrance. I'm clumsy enough without being fastened to a bench unit. Turning the mold over, swapping hands, or striking hinge would be a problem. YMMV
Experience will tell you all you need to know about mold temp.

[kbstenberg]

So from what I gather from the coments so far. Being aware of the sprue puddle an timming its frosting over will do the same and a lot less expensivly. Being new to casting I was thinking that the learning curve would be shortened by watching the mold temp an what is happening with the sprue puddle.
Has anyone seen a problem with cold or hot spots on there molds because of the hole that is drilled for the probe?
Kevin

[casterofboolits]

To me consistancy in how you cast boolits is the most important factor in making good boolits. Control your alloy temperature and mold temp will follow. I cast with multiple molds and rest them on cast iron one pound ingot moulds while cycling the other moulds, the cast iron ingot molds act as heat sinks and help maintain the mould temps. I pre heat my moulds by setting them on top of the lead pots as they heat up.

I use only iron moulds and the smallest mould I use is four cavity and have at least two of each boolit style.

The main thing I check for when casting is boolit fill out with sharp cornors of lands and bases. A bit of frosting doesn't hurt a thing.

So, start casting and if the results aren't what you want, ask for help here. Describe what the problem is, your casting methods, alloy, moulds, bottom pour or dipper and someone here will have suggestions as to how to improve the process.

[Bret4207]

So from what I gather from the coments so far. Being aware of the sprue puddle an timming its frosting over will do the same and a lot less expensivly. Being new to casting I was thinking that the learning curve would be shortened by watching the mold temp an what is happening with the sprue puddle.
Has anyone seen a problem with cold or hot spots on there molds because of the hole that is drilled for the probe?
Kevin

Each and every alloy will have a slightly different "perfect" casting temp. Each and every mould will have a slightly different "sweet spot" for casting it's best boolits. (I know there are casters that say they use the same temp and style for every mould, good for them, it doesn't work for me) Every caster will have a different, sometimes widely different method of pouring, fluxing, cutting the sprue, opinion of when the sprue if perfect to cut, etc.

In short, if you are looking for a way to get the "perfect" mould temp and to use it for all your casting or to pass on that temp as a "perfect" temp to use...I think it's more complex than that. IME the same mould used throughout the year will exhibit a preference for a slight change in mould temp and with at least one mould, pouring style- I have one that wants spout to sprue contact in winter, but an air drop in summer using the same alloy.

I was all het up to so what you speak of at one point several years back. I came to the conclusion that with out a casting machine or very large runs of boolits I was trying to fix something I was already taking care of by observing what was going on and alter my methods slightly. It seemed to me that I might be limiting my flexibility a bit by depending on a mould temp reading. Maybe I'm all wrong on that, but it seemed like a lot of work to me for what I might get out of it.

[btroj]

I am with Bret. Observe. Pay attention to what is happening and to what you mould is telling you.
Learning to tell what the mould it telling you is part of the art of casting. Yes, I said art. Sadly, it is not all science. It takes time to master but the rewards are well worth the price.

Brad