simple Hi-Tek coating

[Jatz357]

Impressive, How do you know the 1st is dry enough to bake? To me getting the 1st coat dry is the most important step.

Great question ioon44, the 1st coat in the most important.

This is a long winded response and is based on many tests and years of experience.

Grab a coffee.

Normally I just pre-heat the projectiles in a drying rack that is enclosed and has fans and heating elements. Only use this during winter and normally 10 minutes is plenty but mostly way longer than that because the drying rack will hold up to about 480kgs. I coat quite a few before I start baking.

I did some tests of short drying times when I was testing the colours.

My shed temp was reading 20.3 C and 43% humidity when I started but the temp was increasing and humidity was dropping.

1st coat the start temp of the bare projectiles read 20.9 C (interesting since shed temp was lower) projectiles had been sitting in a bucket near the roller door that had the morning sun on it so that may explain the higher reading or because of the infrared thermometer was reading a reflected surface.

Directly after the first coat the projectile temp was 15.1 C and they were left on a tray on a bench for 20 minutes.
After 20 minutes they were put into the oven and their temp was 20.9 C exactly what they started at. There was some heat coming off the roller door too.

After 1st bake the smash and solvent tests passed with no issues.

2nd coat the projectiles were 30.6 C still cooling after the first bake. Directly after 2nd coat they were 20.5 C and were left on the same tray for 15 minutes.
After 15 mins they were put back into the oven and their temp read 23.3 C. Shed was warming up and some extra heat from the roller door.

After 2nd bake the smash and solvent test passed without any problems.

I also did another test after 1st bake. Projectiles were 32.6 C before 2nd coat and 16.4 directly after the 2nd coat. I added metho to projectiles and then the coating so I would get a far longer tumble time and this chilled the projectiles more. These were left on the same tray on the bench and put into the oven after 9 minutes and their temp was 21.5 C. After the bake cycle they passed all tests.

During these tests there was no heat or fans used on the projectiles during the dry time. After about 5 to 7 minutes I spread out the pile to allow the touching surfaces to get some air as the touching locations remained wet for a longer time. After the drying time for each batch just before baking no coating would transfer onto my gloves, this showed that all surfaces were at least dry to the touch.

It should be noted that the weather and temperature conditions were very good for fast drying conditions when these tests were conducted.

The coating itself dries very quickly if it is exposed to air and, only the touching surfaces could transfer some coating onto your gloves quite some time later (10 - 20 minutes or more again depending on conditions and amount of coating applied) when the projectiles are moved around. Some damp spots will not cause coating adhesion problems.

I have found that once the coating is dry to touch or press, it can be baked. The issue is with moisture that is trapped between the coating and lead. Acetone is hydroscopic and also has a small percentage of water in it to start with. When the acetone evaporates it chills the alloy and attracts moisture. In extreme cases the coating may appear to go foggy, white or blushing, this is the attracted moisture and in the spay painting industry, we called it blooming.

Nice warm days with low humidity will mean less moisture. If it is cool and or high humidity the chilled alloy will attract a lot of moisture. In the case of cool temps and high moisture the coating will dry as usual maybe require slightly longer dry time however, there is trapped moisture and when the coating is baked, the surface of the coating may skin over and trap the moisture. The moisture will turn to steam and push the coating out of the porous surface effectively breaking the coating bond to the alloy and hench a failed smash test.

With an infrared oven from previous testing, the projectiles heat from inside out and may slow the skinning process of the coating which allows more time for any moisture to escape. This appears to be the reason I can bake projectiles after a short drying time.

Having said all that I am yet to conduct tests when the ambient temperature is cold with high humidity / dew point. I've always pre-warmed the projectiles in winter so I didn't have to worry about moisture related failures.

If you are concerned whether your first coat is dry enough (moisture evaporated) you could simply warm the projectiles. A fan heater or a hair dryer is all you need. As long as the alloy temp is warmer than the ambient temp you should get the moisture evaporated. You only need a few minutes after the coating is dry to touch.

[ioon44]

Thanks for the reply, I have been using Hi-Tek for 6 or 7 years now using a kitchen convection oven.
I use a drying rack that is enclosed and has fans and heating elements also and get the coated bullets up to 50 C to 55 C for 20 min, this insures the coating is dry with no coating failure. My shop is unheated so a lot of my coating is done in 5 C to 10 C weather.
Really interested in your infrared system, looks to be a lot more efficient than a convection oven.

[Tazza]

Excellent reply with lots of good data to back it up.

I found that hi-tek does dry very fast when dissolved in acetone, after 5-10 minutes of letting them dry out, i use the back of a screwdriver to break them up and hopefully move any touching points to allow them to dry. Within 20 or so minutes, they are good to be re-baked.

I'm in an area that usually gets high humidity, summer sees 90% or more in the most hideous times of the year with temperatures in the low 40c range, i try to avoid coating when it's that humid and hot though.

[rfd]

Is Hi-Tek better than PC or ... ?

[Tazza]

I think PC is good for small batches and they look great with their smooth glossy coat and almost limitless colour choices, Hi-tek is awesome for large batches for speed of application, yet does require multiple coats but for me, that's not an issue as it's so fast to do. I can coat tens of thousands of them in a day.

I have never used PC before, and wonder how it will perform with faster speeds as hi-tek is a polymer that sets when baked, PC i thought just gets melted to create a nice even finish. Gun powder creates heat, will it melt off? it obviously works, each to their own really. Like a glock person vs a 1911, do the same job, just different.

[Jatz357]

Is Hi-Tek better than PC or ... ?

Hi rfd

I have very little experience with PC.

From what I have seen the PC will adhere to lead well and appears to stick after a smash test.

PC is designed to coat and protect objects and was not developed as a lead projectile coating. PC will give a thicker coat but may be uneven and can stick together when baked (based on some photos I have seen) One concern is PC may contain silicates, silica dust is dangerous when inhaled and is abrasive. Different PC bands and colours may have different amount of silicate. I would be concerned about high volume use and possible barrel damage. But then again it appears to be widely used.

Hi-Tek is made specifically for projectile coating and has been in use for maybe 30 years or there abouts. Designed to provide a heat resistant barrier between lead and the barrel, designed with lubricating properties and is non abrasive. Deigned to be a thin coating so the lead projectile is not affected by the coating in an adverse way.

Hi-Tek is very easy with high volume coating whilst PC may be difficult to process large batches. PC is probably more suited to the low volume user.

Hi-Tek is really very easy to use if you follow the instructions. Really, it is that simple.

If PC works for you and you get the results you are after then maybe, PC is for you. However if you think there may be an alternative, then give Hi-Tek a go.

[rfd]

PC works Extremely well ... for me. I can even size a bullet, shake 'n' bake, and minutes later resize ... all with minimal effort and time. That polymer coating is well bonded to the tin:lead alloy as proven by a smash test I do for every bake. Once I have a batch of bullets cast, say a few hundred, the time for them to be load ready is less than an hour, sometimes within 40 minutes. I'm not saying PC is better than sliced bread or Hi-Tec, it's just that ... dang ... it works so damn well, for such little effort and expense. I've never done Hi-Tec, that's a huge given, and maybe its forte is massive quantity, and if so, then for sure that would make smart sense. But for the batches of a 100 - 200 that I require, PC is just a no-brainer.

[Ausglock]

Why size before PCing and again after???

PC is too messy for me. Bloody powder everywhere. All over the place...
HITEK is easy and quick. Easy cleanup and is actually made for coating lead bullets.
PC is for lawn furniture.

[rfd]

Why size before PCing and again after???

PC is too messy for me. Bloody powder everywhere. All over the place...
HITEK is easy and quick. Easy cleanup and is actually made for coating lead bullets.
PC is for lawn furniture.

To each their own, mate!

Cheers!

[Tazza]

To each their own, mate!

Cheers!

So very true, if it works for you, stick with it. I'm not going to bag anything that has been proven to work.

[Jatz357]

This is the video I mentioned yesterday that I was going to post.

WARNING: only people with way too much spare time should watch this........

Like watching paint dry?

This is a view of how our infrared oven cures Hi-Tek Supercoat, high performance bullet coating.

Projectiles are spread out on the conveyor belt and the oven does the rest. Approximately 5:30 minutes transit time through the oven and the coating is cured.

This is just a small test of 4.5 kg each of Hi-Tek Dark Green & Blue, first coat.

[ioon44]

Is Hi-Tek better than PC or ... ?

I have used Hi-Tek and PC and have stayed with Hi-Tek.

[Tazza]

This is the video I mentioned yesterday that I was going to post.

WARNING: only people with way too much spare time should watch this........

Like watching paint dry?

This is a view of how our infrared oven cures Hi-Tek Supercoat, high performance bullet coating.

Projectiles are spread out on the conveyor belt and the oven does the rest. Approximately 5:30 minutes transit time through the oven and the coating is cured.

This is just a small test of 4.5 kg each of Hi-Tek Dark Green & Blue, first coat.

Good to see you got your video finished, it's just under 10 minutes long, not an issue watching "paint cure", it also shows that your PID control holds the temperature of the load at 195c by the time it exists the conveyor.

[Jatz357]

Good to see you got your video finished, it's just under 10 minutes long, not an issue watching "paint cure", it also shows that your PID control holds the temperature of the load at 195c by the time it exists the conveyor.

The PID temp control works very well.

Maybe time to upgrade the old computer, it's getting slow when editing videos.

[HI-TEK]

The PID temp control works very well.

Maybe time to upgrade the old computer, it's getting slow when editing videos.

I agree with computers regularly requiring upgrade
I had replaced mine with 2 terabyte hard drive 32megs Ram and afterwards regretted that I id not go with a 128meg ram system.
With all the data, photos and videos, it really slows things down when processing. I am a novice with all this stuff, so I will do a lot of homework before I buy another computer that will work OK for longer term.

[Tazza]

I agree with computers regularly requiring upgrade
I had replaced mine with 2 terabyte hard drive 32megs Ram and afterwards regretted that I id not go with a 128meg ram system.
With all the data, photos and videos, it really slows things down when processing. I am a novice with all this stuff, so I will do a lot of homework before I buy another computer that will work OK for longer term.

It's always good in theory to buy a nice fancy high spec computer do do the work, till it just makes it past warranty and carks it. My wife bought a rather expensive HP laptop, she "needed" the best of the range to do her uni course, one that really didn't need loads of power, but whatever. It lasted 2 years then dead as a dodo. Then needed another best of the best machine, $1,200 Dell was bought again, for uni. Lets see if it makes it longer that 2 years.

They all seem to slow down over time, the more data that you put on them, the slower they get, re-install the operating system and it's fast again, for a time... But who can be bothered doing that every few months? surely not me.

[dansedgli]

How long ago was that, Mb or Gb? 32Gb of ram should be enough for almost anything.

You might be better off with a faster hard drive like an SSD if you don't already have one. The old spinning disks are much, much slower for every day things like loading windows.

I dabbled in PC late last year. I didnt mind it but the coating is patchy if you cook them dumped on a tray rather than standing them up. I found depending on where that patch was, it might jam up your gun if its close to the lands or rifling.

The annoying bit is that the coating melts and sticks the bullets to the tray and to other bullets. You need to break them apart and when you do that section won't be coated. If you leave it a long time they can be very hard to separate. I would dump the hot bullets into water and immediately start breaking them apart.

As far as shooting goes they seem the same to me at pistol speeds up to 1400 fps.

Dealing with powder is annoying, the fine dust gets up your nose a bit and can be a bit messy but you only coat once and there is no drying time.

The bag of powder was quite expensive and there is no way it would last as long as the equivelant amount of hitek but there is no acetone to buy either.

I will be hitekking going forward. They look better, are less likely to cause a gun malfunction and breaking apart bullets was a pain.

[Tazza]

I figured he was talking GB and not MB or else the computer was a dinosaur, even loads of ram doesn't mean it's going to be fast of the CPU isn't up to the task.

I heard apple machines are good for video editing, i hve never owned one though, too hard to get repaired.

Windows based systems are far easier to get parts for.

[HI-TEK]

Hello Dansedgli
As I said I am a novice with all this computer stuff.
It probably was 32Gb of ram. It is about 3 years old. I was advised at that time, that the more ram you have, the faster is the computer.

I have had both European and US casters convert from Powder coating to Hi-Tek. They said that they shake coated in a closed container, then dumped onto baking trays. After a few coats that way, the powder progressively stopped working adequately, and had to be dumped and replaced with new powder.
As advised, what seemed to be happening is, that shaking and coating, the powder was polishing the Lead pellets, leaving polished off finely divided Lead in powder residue, which was used on-going, to coat more projectiles. It was suspected, the contamination had affected the powder being used, and that is why it stopped working well over time..
I had no specific details, but seemed to make sense to me with observations supplied. Over time, I have seen the phenomena of powder coating welded casts with bare metal after breaking stuck ones apart after baking. It works to an extent, but does seem to produce other problems such as you described.
Producing evenly coated cast was also a problematic area as you only had one chance to produce a good coating, and despite looking OK, users were never sure if coating was even with thickness with the film being produced around coated cast.
It is very difficult to get a very thin even coating all around the alloy when using powder coat. This variation shows up with diameter measurement changes on the same projectiles.

[Jatz357]

I agree with computers regularly requiring upgrade
I had replaced mine with 2 terabyte hard drive 32megs Ram and afterwards regretted that I id not go with a 128meg ram system.
With all the data, photos and videos, it really slows things down when processing. I am a novice with all this stuff, so I will do a lot of homework before I buy another computer that will work OK for longer term.

I built my old computer, or more like it, just assembled the components I wanted. It is now about 9 years old and has been the best computer I've had. Originally had 120gig SSD and was very fast but more complex software now is slowing it up. The SSD failed about October last year and now I have an old 2TB hard drive running the OS and that has made it slower. I was lucky because run a good back up and restore system and was able to recover all documents etc that was on the old SSD. The SSD was completely dead and I could not get anything from it at all.