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View Full Version : Hi-Tek Coating question.



steve4102
02-21-2014, 09:06 PM
I know all this has been covered already multiple times, but wading through hundreds of pages and thousands of post got to be a little much, so I thought I would try the direct approach, sorry.

I just got some Hi-Tek from Donnie at Bayou bullets and I'm having some issues.

I followed the directions to a tee.
Mixed 5-5-1
Lightly coated.
Air dried
Baked at 370* for 10 min.
let cool
repeat.

They look good, they feel cured and I cannot remove any coating with pure Acetone.
When I smack-em with a hammer, the coating fractures and flakes off.

The directions say this could be caused by, to thick of a coat and or over cooking.

So far, I have purchased a new convection oven, purchased two new oven thermometers, adjusted my temps from 350, 360, 370, 375, adjusted time from 8, 8.5, 9, 9.5, 10 minutes and I have tried applying the coating as thin as could possibly be.

They all will not pass the hammer test.

What else can I try to fix this?

Also, what about shooting the ones that I have already coated. Will not passing the hammer test render them unfit to fire and back to the melt, or will they be OK?

btroj
02-21-2014, 09:25 PM
Try shooting them. Never know.

Use a reliable oven thermometer to check your oven. Is it a convection oven? If not it may be heating and cooling enough to cause issues.

I adjust cook time for bullet size. 9 mm gets less time than 45. I base it on weight.

I don't do the acetone or hammer test anymore. I have it down good enough to feel those tests aren't needed.

If you undercook I can assure you that it is noticeable. The slight smell of burning plastic is hard to miss. They shot well enough but I cook longer now.

Were bullets extremely clean when coated? I have to think that any grease or oil on the resurface would hinder adhesion.

steve4102
02-22-2014, 12:05 AM
I rinsed them in pure Acetone the day before I tried coating them. Bad idea?

Ausglock
02-22-2014, 01:07 AM
You are probably not leaving long enough after the acetone bath before applying the coating.
Why acetone bath them?

Apply the coating and leave them for MINIMUM of 10 minutes. then warm them with a hair dryer if you are in a cold climate.
Or leave them for a good 1/2 hour.

Which colour?

steve4102
02-22-2014, 08:16 AM
Black

I tried something new with this batch of bullets. I used to cast, lube with 45/45/10, dry, size, lube again.
With this batch, I cast, swirled them in a splash of Mineral spirits, sized then lubed with 45/45/10.
This method worked well and kept my sizing die nice and clean.

I had a bunch that I sized with Mineral spirits, but did not lube.

I took these bullets and gave them a bath in Acetone to clean off any residue from the Mineral Spirits. They sat on a piece of hardware cloth to dry for at least 24 hours.

farmerjim
02-22-2014, 08:43 AM
I have shot boolits that did not pass the smash test with excellent accuracy and no leading. I found that the reason they failed the smash test was the coating was too thick.
Ausglock had a formula (5-1-7 mix. 250 9 mm 125 gr bullets get 7 mls of coating. Easy. No rocket science needed.)
My convection oven is smaller so I do 125 9mm 125gr bullets with 3.5 ml of coating and 2 coats. Works great and does pass the smash test. 3.5 ml is an extremely small amount and hard to measure. I use a syringe and needle that I get at the local Agg co-op. No need to clean hot cast lead with acetone unless you run your oil covered hands over them. My mistakes and learning curve show everything said before me to be true.

steve4102
02-22-2014, 09:42 AM
I'll try 5-7-1 today and see how it turn out.

Thanks

Ausglock
02-22-2014, 04:54 PM
what is 45/45/10??

coat then as cast. don't wash or anything else.
if you have to touch them, wear latex gloves ( I use latex gloves all the time to stop skin/lead contact for personal health safety reasons).

steve4102
02-22-2014, 06:23 PM
OK, here is what I did today.
Mixed up a batch of 5-7-1.

Bought another oven thermometer, this time a fast read digital.

Messed with the oven and the New Digital thermometer until I was able to get a very consistent 365-370* the entire 10 minutes of cook time.

Cooked three batches of 5-7-1, two coats each. They passed the hammer test and look good. The finished product was a little different color than my previous attempt. The first attempt was almost Black with a green tint. This new batch of 5-7-1 was almost black with a brown/red tint.

As I changed two things at once, the ratio and the oven. I made another batch with 5-5-1 and cooked them with my new oven technique. They came out Black/green and did not pass the hammer test.

My conclusion is 5-7-1 is the way to go and consistent oven temps is key, but less important than coating thickness.

I want to thank you guys for all your help. Now off to the range, oh wait, scratch that, it's under 4 feet of snow.

steve4102
02-22-2014, 06:26 PM
what is 45/45/10??

.

It's is a tumble lube formula that consists of 45% Alox, 45% Paste wax and 10% Mineral Spirits.

Ausglock
02-22-2014, 10:07 PM
It's is a tumble lube formula that consists of 45% Alox, 45% Paste wax and 10% Mineral Spirits.
Well ditch that stuff.
You no longer need it.

If you tried to remove this crud and then coat with hi-tek, then you would have a fail. If you are going to coat pre-lubed bullets, the only way to coat them is to re-melt and re-cast.

btroj
02-23-2014, 12:53 AM
Steve, I have even gone with 1/5/9 to get better coverage on the books and crannies of a 200 swc.

I would rather do 3 thin coats than 2 heavy ones.

Love Life
02-23-2014, 01:14 AM
And my $30 wally world special oster oven keeps chugging along...

Sounds like you have it figured out, now go enjoy!!

Moonman
02-23-2014, 08:43 AM
Personally, I think the money spent ($250) for a Breville BOV 800XL "SMART" CONVECTION oven was well spent.

It just basically WORKS OUT OF THE BOX.

I didn't spend or WASTE too much time other than a few e-mails to TREVOR (Ausglock)

and Donnie at Bayou Bullets, I've been coating and SHOOTING THEM. (GOLD 5/1/7 RATIO MIX)

Some folks have added PID'S to their Baking ovens or found out that THEIR cheap

oven WILL NOT GET THE JOB DONE. Wasted time to me.

To each his own though.

My retirement time IS REALLY VALUABLE TO ME.

GOOD CASTING AND COATING EVERYONE.:grin:

btroj
02-23-2014, 08:49 AM
And my $30 wally world special oster oven keeps chugging along...

Sounds like you have it figured out, now go enjoy!!

Mine was on sale for 35 at Menards. It just works. What else does it need to do?

Moonman
02-23-2014, 09:05 AM
Glad you two have cheaper ovens THAT WORK FOR YOU, many HAVE NOT.

Loaded up a couple hundred this morning, 148 Button Nosed, 158 SWC 38 Specials.

Time for a bath and then OFF TO THE RANGE (indoor).:Fire:

Later Guys.:grin:

Ausglock
02-23-2014, 07:07 PM
I'm soon getting a travelling table Pizza oven to try.
It is $1400 Aus but may be worth the money if it works ok.
They have top and bottom heating with fan convection. The entry and exit has shutters that can be closed down to allow just enough space for the trays of bullets to enter and exit.
Time can be set from 8 to 20 minutes for the travel time in the oven.

Moonman
02-23-2014, 08:32 PM
Trevor,

Now that will be a BULLET BAKIN' Sum Beech.

Ausglock
02-24-2014, 04:55 AM
Yep. I hope so. Will chew electricity I think.
They do a propane version too.

Love Life
02-25-2014, 01:50 AM
Mine was on sale for 35 at Menards. It just works. What else does it need to do?

Sure is nice. Perfect coated bullets every time. A digital timer was the best thing to happen to my coating regimen. I shot some last weekend at the Nevada get together that I coated in summer 2013. They've been sitting in an ammo can in my hot to freezing to hot garage.

I use a 5:1:9: ratio with red/copper.

HI-TEK
02-25-2014, 05:22 AM
I know all this has been covered already multiple times, but wading through hundreds of pages and thousands of post got to be a little much, so I thought I would try the direct approach, sorry.

I just got some Hi-Tek from Donnie at Bayou bullets and I'm having some issues.

I followed the directions to a tee.
Mixed 5-5-1
Lightly coated.
Air dried
Baked at 370* for 10 min.
let cool
repeat.

They look good, they feel cured and I cannot remove any coating with pure Acetone.
When I smack-em with a hammer, the coating fractures and flakes off.

The directions say this could be caused by, to thick of a coat and or over cooking.

So far, I have purchased a new convection oven, purchased two new oven thermometers, adjusted my temps from 350, 360, 370, 375, adjusted time from 8, 8.5, 9, 9.5, 10 minutes and I have tried applying the coating as thin as could possibly be.

They all will not pass the hammer test.

What else can I try to fix this?

Also, what about shooting the ones that I have already coated. Will not passing the hammer test render them unfit to fire and back to the melt, or will they be OK?

From description you supplied, there are two possibilities, (may be 3)
1. First coat much too thick
2. Not dried enough with thick coat.
3. Possibility, Acetone may be no good.

First coat needs to be almost called a stain. It is not pretty, but as long as majority is coated it is OK.
Dry well even if warming with a dryer. (Cold conditions wont allow adequate drying, and despite feeling dry the coating is not dry.
First coat, especially if thick, will trap moisture which when heated in oven forms super heated steam, which prevents bonding.
Coating may be cured by heat but not stuck to alloy.
Test first coat before you coat a second time, as you cant fix bad first coat after heating and no adhesion. It is a re-melt.

steve4102
03-02-2014, 07:54 PM
Thanks

steve4102
03-04-2014, 11:11 AM
Of your list of possible reasons you did not mention cook time or heat control.
Is this less of an issue or no issue?

Ausglock
03-04-2014, 04:04 PM
heat is critical. Time not so much (10 to 12 minutes).
what is also critical is the first drying time and temp after coating and before baking.
The bullets must not "feel cold". if they are colder than your hand, warm them up with a hairdryer or while your oven is heating up to temp, place the tray of bullets on the top of the oven to pre-heat them. This is what I do. even in summer, I still do this.

Use good quality acetone. not cheap bulk store stuff.

steve4102
03-05-2014, 07:42 PM
I loaded a 100 rounds of the bullets that did Not pass the hammer test.
My RIA 10MM has a bore diameter of .401+ so I have been sizing my tumble lubed bullets to .402+.
These coated bullets were sized to .401 after coating.
Here is the target, 25 yards sand bag, 9* little wind. Accuracy is on par with my other 45/45/10 cast bullets.
http://i2.photobucket.com/albums/y17/steve4102/HiTek1_zps82d97b09.jpg

Here is what came out of the barrel with my Chore-Boy scrubber. Not bad, way less than my .402+ 45/45/10 bullets.

http://i2.photobucket.com/albums/y17/steve4102/HiTekbarrel_zpse1304ba5.jpg

My next batch will be loaded with those that passed the hammer test, I am sure the results will only improve.

Thanks guys.