simple Hi-Tek coating

[slide]

Joe, this kinda backs up your last post. I took two digital themometers with thermocouples. One with a bullet attached one was bare. Both were put in with a batch of bullets. When the one with the bullet reached 360F the bare one read 376F. There was a least 10F difference during the four minute countdown. I know these thermometers are correct. My son owns a water testing lab and we have a tech guy come every six months and check our thermometers and scales,calibrate them if necessary and certify them. I asked him if he would check these thermometers which he did. He said they were on the money. I realize it is only a crude test. Any suggestions?

[Petander]

Petander, that colour red is close enough to the colour I'm getting. As you say, it works, which is all that matters. The purple looks nice, might have to try that. Wonder if you'd get the same result by bumping up the temp instead of a long bake time?

The long bake time is for heat treating,it's easier to keep lower temp (200°C) and have a longer time marginal for the required BHN. 14-16 for rifle in this case. Higher temps generally turn colors black faster. And obviously give a higher BHN which I don't want.

My bullets go to 210-220 C (425F)then.

EDIT: This chart is for WW,my alloy in question is 50 pure/50 WW.

[HI-TEK]

Joe, this kinda backs up your last post. I took two digital themometers with thermocouples. I realize it is only a crude test. Any suggestions?

Slide,
To test temperature rise comparison between coated and non coated cast, it would be great if you can say set up an oven at 180C. Bore a hole into non coated cast, and also in a single coated cast and insert probes into bases. Place them onto the oven. Start to record temperatures, say at every 30 seconds until they both stabilise with temperature.
Repeat this with plain alloy and twice coated cast.
Repeat again with 3 times coated cast and non coated cast.
This should provide a temperature rise profile that can be plotted on a graph temperature versus time. It should reveal just how much the coating slows down the heat transfer with each coat.
Please advise
Joe

[Petander]

I wonder how much temp variation everyone else is getting?

IR meters may not read the absolute truth (reflective coating) but relative hot/cold spots are easy to find. My variation (My 5 lbs accuracy bake setting) is 10° C @ 4.30 min, then all my bullets are 180-190 °C. Hot spot is on the right side,coolest in the middle and medium on the left side. I let them go to 8 min.



I do bake 10 lbs quite often,just give a few more minutes and a tad more temp to begin with,TMG Gold is very tolerant.

[slide]

Give me a few days and I will give it a try. I thought of something. Do the hi-tek coated bullets need to be the same color?

[Petander]

Give me a few days and I will give it a try. I thought of something. Do the hi-tek coated bullets need to be the same color?

I would use one color,less possible variables that way.

[slide]

After I posted that question and looked at it I thought DUH! slide. What are you thinking. Joe ,I am going with the gold 1035. Like a lot of folks it is my favorite.

[HI-TEK]

Give me a few days and I will give it a try. I thought of something. Do the hi-tek coated bullets need to be the same color?

Slide,
To get results on a particular coating, simply do the test with same colour of choice.
You can always repeat tests using different colours as a comparison.
My guess is, that all metallic colours should exhibit very similar heat transfer rates.
They should also reduce heat transfer rate at similar rates, as compared to plain Lead.
Plain coloured coatings will also reduce heat transfer rates, but a guess is that they will be only marginally less than the metallic. May be, the tests will tell all, or may be not.
Love experiments like this as it reveals the reality.
Another variable is coating thicknesses.
Most put on about an average of 1 thou per coating. So two coats will be 2 thou and three coats will be 3 thou.
Results then can be tabled as heat transfer rates per thou of an inch.
My guess is, that as thickness of coatings increases, that will slow down heat transfer rates into the alloy also.

[HI-TEK]

[QUOTE=Petander;4767954]I wonder how much temp variation everyone else is getting?

IR meters may not read the absolute truth (reflective coating) but relative hot/cold spots are easy to find. My variation (My 5 lbs accuracy bake setting) is 10° C @ 4.30 min, then all my bullets are 180-190 °C. Hot spot is on the right side,coolest in the middle and medium on the left side. I let them go to 8 min.

Petander,
these sort of heat variations in ovens are quite normal, especially when air circulation is inadequate or non existent.
I have always recommended fan forced air in ovens, and the fan forced air is faster the better, like a mini cyclone.
That sorts out hot and cold spots, and product comes out very even in colour and bakes very evenly.
I have seen baked projectiles come out of same tray, some pass solvent test, and others fail.
This was directly due to uneven heat distribution inside oven.
I saw years ago, a conveyor oven, where thermometer said 200C, the tray of coated cast went through in about 10 minutes, but when tray was exiting oven, the casts on edges of tray were molten Lead, and in the middle it was not baked. That is how much heat variation was inside oven without fan forced air circulation. Measuring air, is no guarantee what is temperature of the product being baked, unless that air is a mini cyclone around the load being baked.

[Petander]

[QUOTE=HI-TEK;4768367]

I wonder how much temp variation everyone else is getting?

IR meters may not read the absolute truth (reflective coating) but relative hot/cold spots are easy to find. My variation (My 5 lbs accuracy bake setting) is 10° C @ 4.30 min, then all my bullets are 180-190 °C. Hot spot is on the right side,coolest in the middle and medium on the left side. I let them go to 8 min.

Petander,
these sort of heat variations in ovens are quite normal, especially when air circulation is inadequate or non existent.
I have always recommended fan forced air in ovens, and the fan forced air is faster the better, like a mini cyclone.
That sorts out hot and cold spots, and product comes out very even in colour and bakes very evenly.
I have seen baked projectiles come out of same tray, some pass solvent test, and others fail.
This was directly due to uneven heat distribution inside oven.
I saw years ago, a conveyor oven, where thermometer said 200C, the tray of coated cast went through in about 10 minutes, but when tray was exiting oven, the casts on edges of tray were molten Lead, and in the middle it was not baked. That is how much heat variation was inside oven without fan forced air circulation. Measuring air, is no guarantee what is temperature of the product being baked, unless that air is a mini cyclone around the load being baked.

Yes,mine is a 2,2 kilowatt household wall oven with two fans. A no-fan oven gives quite a bit of colour variation. Got one,too. And a 600 watt mini toaster,a complete joke.

[Petander]

What is "TMG" short for in TMG Gold?

[slide]

Joe, I sent the test results to your gmail address. I couldn't get the pm to work. You got two emails. I had a power surge just as I sent the results. I hope it got through. If not I will send again. I hope it helps.

[HI-TEK]

Joe, I sent the test results to your gmail address. I couldn't get the pm to work. You got two emails. I had a power surge just as I sent the results. I hope it got through. If not I will send again. I hope it helps.

Hello Slide,
Thanks much, the results you sent by email has arrived OK.
You did a great job with this.
Results you obtained, definitely confirm that coating slows down heat transfer rates to the alloy.
Great work, and thanks much.
I am going to try and put it onto graph paper so it is a visual comparison between Lead and coated Lead temperatures from start to finish.

[HI-TEK]

What is "TMG" short for in TMG Gold?

Petander,
That is the code that was used to differentiate this gold from the many others we have.
There is Solar Gold, Aztec Gold, Glitter Gold, Antique Gold, Gold 1035, Sunny Gold and Old Gold.
These all work just great and were specifically made for commercial casters who wanted their unique colour.
The TMG came about due to people wanting a much brighter gold and the TMG Gold has a different makeup composition with trying to obtain the brightness.
Down side is, that ingredients for the TMG Gold are very expensive, and may not be commercially viable.

[Petander]

Petander,
Down side is, that ingredients for the TMG Gold are very expensive, and may not be commercially viable.

Yes we have talked about this. I still would like a kilo because my high pressure/velocity developments all used TMG,it absolutely shines. Even though I still don't know what "TMG" means... "Too Much Green?" Or "To Markku with Greatness?"

Here in Finland coating cost is nothing compared to primers and powder. I want the best whenever possible,not cheap. Niobium,my alloy contaminant, may have a role here.

[HI-TEK]

[QUOTE=Petander;4769020]
Even though I still don't know what "TMG" means... "Too Much Green?" Or "To Markku with Greatness?"

Petander,
you were closer with the "Green" as ingredients introduced a Green tone to the gold colour.

To know formula, it is simple, just buy the whole technology, and you will have all revealed.

[Tazza]

To know formula, it is simple, just buy the whole technology, and you will have all revealed.

I'll bid you $200, am i close?

Are you out of danger with the fires? it's still dry as up here and windy, lots of smoke haze, gives awesome sunrises and sunsets, but i don't want the flames.

My grass is nice and yellow, just looking at it sideways i swear it could catch fire.

[Petander]

[QUOTE=HI-TEK;4769030]

To know formula, it is simple, just buy the whole technology, and you will have all revealed.

Thank you for the generous offer but I better pass.

Reminds me of working in a recording studio once. Band walks in "You have all this equipment, make us sound like Van Halen!"

I said : "To sound like Van Halen,you have to PLAY like Van Halen".

[Tazza]

[QUOTE=Petander;4769263]

Thank you for the generous offer but I better pass.

Reminds me of working in a recording studio once. Band walks in "You have all this equipment, make us sound like Van Halen!"

I said : "To sound like Van Halen,you have to PLAY like Van Halen".

hehe nice, i bet some people are serious, they think all the fancy audio gear can make anyone sound awesome, if that was true, you wouldn't have worked at a studio, you'd be recording your own stuff

[Petander]

[QUOTE=Tazza;4769549]

if that was true, you wouldn't have worked at a studio, you'd be recording your own stuff

.

I've been mostly working on my own stuff for decades indeed.

But I can not use a coating formula. What would be a minimum order for The Original TMG Gold? So that making a new batch would make sense to Joe,too?

It is The King of rifle/hi pressure coatings.