I'm Painting My OE Wheels - Not PCing - Here's Why
07-10-2015, 11:14 PM
#63
NO ****! lol
AS someone who has sandblasted for 10 years, it is unlikely even an industrial unit can super heat the surface; that is just ridiculous.
I have sandblasted a gloved hand before to see what it felt like and really no heat at all.
Direct contact for hours, then yeah, maybe.
Again I believe the absolute top thresh-hold is 400. With that said the thickness of the metal has something to do with it as well.
High Strength Al. Alloys can change their grain structure as low as 100 degree.
And it is not THAT they change at these low temperatures, but how they react when cooling through normalizing. No quenching is done, soooooo what happens? Normally nothing.
07-10-2015, 11:47 PM
#64
Ok thanks ls NIK and 54. I overestimated the amount of localized heat. That much is clear.
Removing enough material to actually weaken the wheel seems like a pretty big error though doesn't it? That's all I was attempting to rationalize. Seems improbable as well.
Removing enough material to actually weaken the wheel seems like a pretty big error though doesn't it? That's all I was attempting to rationalize. Seems improbable as well.
07-11-2015, 08:08 AM
#65
There are different sizes of sandblasters and the medium they use. Many commercial powder coaters are setup to work at an industrial level and I can assure you a diesel powered, constant flow sandblasting rig running a 1" hose/nozzle combo pushing a course medium at full bore (that's the only way isn't it) could damage an (edit: aluminum) wheel in a few seconds if it isn't handled properly. Lay the powder on thick and heavy and you'd probably never know the difference.
Is it hard to control a 1" hose attached to a 80hp diesel powered air compressor? I'll let you figure that one out.
Edit 2:This much we know, the powder coating process shouldn't be hot enough to cause problems. Trust me, it isn't temperature related stress cracking from the blasting process so what else could it be but too much material being removed (and not evenly around the wheel, only in random localized spots) by aggressive sandblasting techniques?
Last edited by ls1247; 07-11-2015 at 08:26 AM.
07-11-2015, 09:51 AM
#67
Wrong tool for the job? Yes, but if you simply dropped you're wheels off at some random powder coater, that might just be what you get because that's how a lot of them (around here anyway) are set up. How were the wheels prepped that actually broke, guess we'll never know but it could have easily been done like this.
After this conversation, I think I'd be comfortable with bead or some other "soft" media blasting and powder coating.
Thanks
08-24-2015, 07:07 PM
#72
I stand corrected...
I inherited a set of f14s on a car I just bought (2 of which I had straightened) and they have a thin coat of plastic dip over a factory gold finish so its time for powder coating. Instead of going to the rusty dumpster blasting guy down the street, I sought out a more delicate alternative and found a soda blaster close by.
This guy does sand, glass and soda blasting and he insist that it is possible to introduce enough heat into a wheel sand blasting it to cause small fracturing as isis predicted. If you know what you're doing, sand blasting isn't an issue but in the wrong hands, it can be a problem.
Soda blasting alone isn't enough though as it will leave the surface, in his opinion, too slick for powder coating to stick in the long run. He normally does a sand blasting with extra fine sand which leaves the surface just rough enough for the powder to stick.
Based on this, I felt it might be worth the extra coin to have him blast all the finishes off with soda to keep heat to a minimum and then have him lightly sand blast the bare wheel to give it the texture it needs.
I inherited a set of f14s on a car I just bought (2 of which I had straightened) and they have a thin coat of plastic dip over a factory gold finish so its time for powder coating. Instead of going to the rusty dumpster blasting guy down the street, I sought out a more delicate alternative and found a soda blaster close by.
This guy does sand, glass and soda blasting and he insist that it is possible to introduce enough heat into a wheel sand blasting it to cause small fracturing as isis predicted. If you know what you're doing, sand blasting isn't an issue but in the wrong hands, it can be a problem.
Soda blasting alone isn't enough though as it will leave the surface, in his opinion, too slick for powder coating to stick in the long run. He normally does a sand blasting with extra fine sand which leaves the surface just rough enough for the powder to stick.
Based on this, I felt it might be worth the extra coin to have him blast all the finishes off with soda to keep heat to a minimum and then have him lightly sand blast the bare wheel to give it the texture it needs.
08-25-2015, 03:28 PM
#73
I stand corrected...
I inherited a set of f14s on a car I just bought (2 of which I had straightened) and they have a thin coat of plastic dip over a factory gold finish so its time for powder coating. Instead of going to the rusty dumpster blasting guy down the street, I sought out a more delicate alternative and found a soda blaster close by.
This guy does sand, glass and soda blasting and he insist that it is possible to introduce enough heat into a wheel sand blasting it to cause small fracturing as isis predicted. If you know what you're doing, sand blasting isn't an issue but in the wrong hands, it can be a problem.
Soda blasting alone isn't enough though as it will leave the surface, in his opinion, too slick for powder coating to stick in the long run. He normally does a sand blasting with extra fine sand which leaves the surface just rough enough for the powder to stick.
Based on this, I felt it might be worth the extra coin to have him blast all the finishes off with soda to keep heat to a minimum and then have him lightly sand blast the bare wheel to give it the texture it needs.
I inherited a set of f14s on a car I just bought (2 of which I had straightened) and they have a thin coat of plastic dip over a factory gold finish so its time for powder coating. Instead of going to the rusty dumpster blasting guy down the street, I sought out a more delicate alternative and found a soda blaster close by.
This guy does sand, glass and soda blasting and he insist that it is possible to introduce enough heat into a wheel sand blasting it to cause small fracturing as isis predicted. If you know what you're doing, sand blasting isn't an issue but in the wrong hands, it can be a problem.
Soda blasting alone isn't enough though as it will leave the surface, in his opinion, too slick for powder coating to stick in the long run. He normally does a sand blasting with extra fine sand which leaves the surface just rough enough for the powder to stick.
Based on this, I felt it might be worth the extra coin to have him blast all the finishes off with soda to keep heat to a minimum and then have him lightly sand blast the bare wheel to give it the texture it needs.
08-25-2015, 05:43 PM
#74
While the goal wasn't to prove you an idiot, I think several of us have more experience with sand/bead blasting than you do. According to the guy who does it everyday, theory seems to have won out.
08-25-2015, 08:13 PM
#78
I guess the bottom line is that nobody in this thread does this for a living so I'll take someone's opinion that does it everyday.
While the goal wasn't to prove you an idiot, I think several of us have more experience with sand/bead blasting than you do. According to the guy who does it everyday, theory seems to have won out.
While the goal wasn't to prove you an idiot, I think several of us have more experience with sand/bead blasting than you do. According to the guy who does it everyday, theory seems to have won out.
08-25-2015, 09:13 PM
#79
1. the opinions are that the powder coating process isn't hot enough to damage or alter the wheel.
2. nobody seems to have coated over the existing finish although some powder coaters might try
3. there are several ways to remove the old finish...
a. cold chemical stripping probably isn't a bad way to go if you have a week to let them soak and you have someone who does it in your area.
b. hot chemical stripping should probably be avoided.
c. sand blasting shouldn't be a problem if good technique and a fine grade of sand is used. Be careful who you choose to do this.
4. ask your powder coater if they need a "texture" on the wheel for the finish to adhere properly. In my case it seems to make sense to remove the finish with a less aggressive medium (soda) and then lightly sand blast the wheel to texture it per the powder coaters request.
As I'm actually in the process of powder coating a set of wheels, I found enough good information in this thread for it to be useful.
08-26-2015, 06:31 PM
#80
Maybe this will help...
1. the opinions are that the powder coating process isn't hot enough to damage or alter the wheel.
2. nobody seems to have coated over the existing finish although some powder coaters might try
3. there are several ways to remove the old finish...
a. cold chemical stripping probably isn't a bad way to go if you have a week to let them soak and you have someone who does it in your area.
b. hot chemical stripping should probably be avoided.
c. sand blasting shouldn't be a problem if good technique and a fine grade of sand is used. Be careful who you choose to do this.
4. ask your powder coater if they need a "texture" on the wheel for the finish to adhere properly. In my case it seems to make sense to remove the finish with a less aggressive medium (soda) and then lightly sand blast the wheel to texture it per the powder coaters request.
As I'm actually in the process of powder coating a set of wheels, I found enough good information in this thread for it to be useful.
1. the opinions are that the powder coating process isn't hot enough to damage or alter the wheel.
2. nobody seems to have coated over the existing finish although some powder coaters might try
3. there are several ways to remove the old finish...
a. cold chemical stripping probably isn't a bad way to go if you have a week to let them soak and you have someone who does it in your area.
b. hot chemical stripping should probably be avoided.
c. sand blasting shouldn't be a problem if good technique and a fine grade of sand is used. Be careful who you choose to do this.
4. ask your powder coater if they need a "texture" on the wheel for the finish to adhere properly. In my case it seems to make sense to remove the finish with a less aggressive medium (soda) and then lightly sand blast the wheel to texture it per the powder coaters request.
As I'm actually in the process of powder coating a set of wheels, I found enough good information in this thread for it to be useful.