Thanks for the reply, looks like a really nice set up.
Where did you place the K sensor or does it matter with the convection fan running?
Happy new year to every one.
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Thanks for the reply, looks like a really nice set up.
Where did you place the K sensor or does it matter with the convection fan running?
Happy new year to every one.
The K sensor is an 8" long one that enters at the top left rear of the compartment. It sits about 2" from the top element.
There is another enrty point at the top left front. It is 4" from the top element. I placed another K sensor in there for testing the accuracy of the rear sensor.
Once the oven came to 200 degC on the rear sensor, the front sensor (on a seperate temp reader) also indicated 200deg C, so being close to the element is no problem.
At the 7 minute mark, I cracked the door and shot the bullets on the tray with an IR thermometer. The bullet were reading 203deg C when the oven was indicating 201deg C.
Good enough for me.
HITEK Joe wants me to plug a sensor in the middle of a bullet and log the alloy heatup time against the oven indicated temp.
I will one day when I get time..
Hooroo.
Regards, Trevor.
Australia
Hi everybody
I've 10 kgs of Lee 358-124rf here and K green HT powder to play around with.
half are COWW and half are COWW but given a weak acid bath before casting to degrease
I'm going to
batch them in 400g
wash them in acetone
warm them with a hairdryer
give them 2mls of 20g ht/120ml acetone/20ml meths
cut with + 1ml acetone,don't want it too thick applied with a syringe
swirl them for < 10 seconds in a plastic 5l bucket,any longer they dry out
dry them for 30 minutes on a perforated steel sheet under a fan(its 22'C/71f)
bake for 10 minutes in my toaster oven with a digital thermometer
Then the bullets will fail the smash test,will pass the acetone test but I will be able to scrape the coating off with my fingernail.This is an improvement,they never used to pass the acetone test.
This is what always happens and I can't figure it out.
any suggestions and tips gratefully received
MARK
Beats me what your got going on.
I coated and baked 25,000 9mm today. all with 2 coats of Kryptonite green powder mixed 20gms to 100 mls @ 6mls per 2.5kg of alloy.
The only thing different that you have to what I have is the alloy.
Hooroo.
Regards, Trevor.
Australia
how do you measure that?
Measure what???Originally Posted by marky123
The Number 1 reason why coating does not stick is that it is NOT dry before baking.
Go to walmart etc and get a heater fan. They are cheap. set it in front of your tray of coated bullets and warm them so that you can feel that they are warm. Then bake them.
Hooroo.
Regards, Trevor.
Australia
Will do.
You use your powder scale to weigh the 20 gms of powder and a glass with mil measurements on it or a large syringe to measure the 100 mil acetone. (if I’m doing smaller batches I’ll go 10 grms to 50 mil.
Put a couple bullets in the solution and mix well. Let the solution sit for at least 1 hour before coating.
I measure my 6 mil solution with a syringe to 4.5 lbs of bullets http://www.ebay.com/itm/131914131871...%3AMEBIDX%3AIT and Clear Polyethylene Tubing 1/4" OD .170" ID http://www.ebay.com/itm/162307454411...%3AMEBIDX%3AIT
Cut the tubing to stick out of the container, mix the solution, plug the syringe into the tubing, suck up the 6 mil of solution. Remove the syringe from the tubing. Squirt on the bullets and swirl/ shake for 15 – 20 seconds then dump onto drying screen. I put the screen/tray in front of a fan with room for the air to blow under until dry. Then I put the tray of dry coated bullets on top of the oven for 1 cook cycle 10 min for my oven.
The first coat should not give you dark coverage and usually looks very thin. That is what you want.
You should not smelt you lead in your casting pot. Your lead should be smelted, fluxed and clean, cast into ingots before you start casting. This keeps your pot clean.
A) no need to etch the lead, because if you smelt them into ingot first and fluxed correctly you have clean lead.
b) the reason it fails the smash test is because it has not dried all the way to the lead.
c) the reason it passes the wipe test is because you have cure the surface of the coating. but because you failed at B. the coating, although set,activate,cured (pick a word) has not bonded with the alloy.
d) I cant see the need for the metho, you have already increased swirl time with the addition of an extra 10mls of acetone, going from 100 to 120. 20:100 is not a "thick" mixture by any streach of the imagination, so 20:120 is 25% thinner.
From what you describe is your method, I think you are close, but not quite dead centre.
Mike.
Don't worry about life, no-one gets out alive.
Mark.
This is great.
Do this.........
Hooroo.
Regards, Trevor.
Australia
This is the acetone test
This is the smash test
This is the fingernail test.
I heated the coated bullets for 30 minutes under a fan heater then baked them.
Shall I shoot a few?
Marky, thanks for your post.
I just want to get things in order,
1. Is that one coat? The coating seems much too thick.
2. Acetone test simply exposes under cooked coatings.
3. Smash test reveals adhesion problems. Your smash test showed poor adhesion. I am not surprised at your ability to scratch off baked coating, as it is very clear that it has not stuck to alloy.
4. You can shoot these, but I doubt you will be happy with results.
5. Adhesion problems are in majority are caused by thickly applied coatings that trap moisture. Coatings will bake cure, but poor adhesion results as moisture lifts coating off the alloy, and, coating is baked but not bonded..
6. I have seen previously, (rare but possible) alloy that contained Zinc and Cadmium metal. If your alloy contains either or both, you will have adhesion problems also, as coating reacts with these metals at alloy surface and results in poor bonding.
My suggestion at this stage is for you to obtain a known alloy 92:6:2 mix, and cast and coat this as a comparison.
Please advise in detail your coating procedures.
I am assuming at this stage, that you are not using any release agents/lubes during casting.
Hi Joe
1.Two coats
2.cooked ok
3.still not cracked that nut.
4.I darent,it takes to long to clean the barrel
5.2mls 20gHT/120mlacetone/20ml meths +1 ml acetone per 800g bullets x 2 coats 200C x12 minutes
6.COWW is my alloy of choice.I cleaned the mould cavities with acetone and smoked it with a butane lighter.
I've an idea.Its probably the same money to send 1kg of my bullets to someone knowledgable to coat than to buy 92/6/2 alloy.I'll pay that person $50 for their time to run my bullets through their coating process.Australasia based,no offence.
Any takers?
MARK
[QUOTE=marky123;3900256]Hi Joe
1.Two coats My question is, did you test after first coat and before you coated a second time? If first coat had failed tests, coating and baking again, wont fix adhesion problems with first coat
2.cooked ok How did you determine this?
3.still not cracked that nut. You must get first coat bonded, before you coat again. Applying two coats wont fix bad first coat problems. The coating has specific requirements. (a) must be applied thinly, dried very well,especially first coat. (b) coating and alloy must reach to 180C and kept there at minimum of 90 seconds after reaching 180C
4.I darent,it takes to long to clean the barrel
5.2mls 20gHT/120mlacetone/20ml meths +1 ml acetone per 800g bullets x 2 coats 200C x12 minutes. Are you sure that with first coat, you actually are getting alloy to at least 180C?
6.COWW is my alloy of choice.I cleaned the mould cavities with acetone and smoked it with a butane lighter.
I've an idea.Its probably the same money to send 1kg of my bullets to someone knowledgable to coat than to buy 92/6/2 alloy.I'll pay that person $50 for their time to run my bullets through their coating process.Australasia based,no offence.
Any takers?
MARK[/QUOTE
I am sure that someone may take up your offer. The problems you face is that all commercial casters are flat out with their orders. They would have to essentially stop what they are doing to do your product.
[QUOTE=HI-TEK;3900280]In that case,whats that alloy formula please?
92 Lead,6 tin??,2 antimony???
Nobody wants this to work more than me Joe,but I'm no further along than I was in September when it arrived.
A bit grayer perhaps...
MARK
[QUOTE=marky123;3900389]Mark,
Before we go to a standard alloy, can I please ask for you to go through this.
1. MIXTURE 20gms powder to 100-120 mls solvent. Use 6 mls of this mixture to quickly coat (10-15 seconds tumble coat) 250 cast bullets. Dump these onto drying mesh, and don't worry about appearances or if they are not evenly coated and are wet. You should not have excess mixture inside your coating container.
2. When you think they are dry, place mesh on top of your oven, with an air gap between mesh and oven. Warm air will help completion of drying.
Take a few, 4 or 5 off the mesh, and cook these for 10 minutes at 200C. Take them out of oven and examine after cooling. Take a picture close up if possible.
Do your tests. If coating passes smash and solvent tests, size them through your sizing system, to see what happens. Send me picture of the few you baked.
3. If first baked coating is found OK, only then, bake the rest from drying mesh as located from on top of your oven.. Now, because of your increased metal loading, the recovery temperature in oven may take longer to get to where it is required for cooking conditions. (It is possible, that cooking time may require an additional 2-3 minutes, and will greatly depend on your oven capacity, air circulations etc etc.)
4. Take out the bulk 245 baked bullets, cool, and take a picture as is. Send me this picture. Compare appearance of the few baked first, to the 245 baked, side by side, and see if any differences can be noticed.
5. Once the bulk, (245) are cool, test with smash and solvent, and size a few. Record results. If all seems OK, only then, coat the lot again, using 6mls mixture, coat quickly, (10-15 seconds), then dump on mesh to dry. Repeat all steps as done with first coat, taking care that every step is the same as done with first coat.
If you find problems with first coat after baking, don't bother to second coat. Additional coats wont fix previous problems. You must investigate why first coat failed.
Please send me detailed results with photos, and I will then try to identify any problematic areas.
Jesus........Pm me. I'll coat em and bake em.
It isn't rocket science.
Today I was coating and baking. But it started raining. Rh went to 99%.
coating wasn't drying, the bullets still felt cold. Coated bullets were cloudy looking. So I stopped coating/baking and started casting.
You have to use the old noggin with this stuff. Will coat/bake when the rain stops and the RH drops a bit.
Hooroo.
Regards, Trevor.
Australia
Maybe we need to look at the oven. The casting alloy isn't the problem, I cast and coat pure lead, coww, Linotype to 33 bhp and all coats well.
You need to test your oven temp by putting an oven thermometer in the middle of the shelf you bake the bullets on. Adjust your oven until the thermometer on the shelf reads 400F. Cool the oven and repeat a couple times to make sure its set right. When the oven thermometer in the oven reads 400, make a note at what your oven is set at. Almost all counter-top ovens are off, some up to 50 degrees. You should have a PID temperature controller for the oven but that's not a 100% requirement. When you are absolutely sure your oven is set to reach 400 degrees.
If your bullets are kept clean and dry after you cast them (no solvents) and you follow the process I previously outlined and bake the bullets for 12 min. When they are completely cool do the rub test and smash test. I see no reason they shouldn't pass.
reasons for coating failure:
1) improperly mixed solution
2) coated to thick
3) not cooked long enough
4) oven not hot enough
Will report back thanks everyone
where abouts are you Mark?
Don't worry about life, no-one gets out alive.
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