Blast roof or ???

[robking]

Hey folks,

Used a 3M clean/strip disc to get roof down to metal. Lot of shallow pits and "stains".

Thinking glass "clean bite" from Northern Tool, shallow angle and low pressure (60 psi) to clean this
up. But its a big, flat expanse and it's nice and flat at the moment. Any other options I should
consider? I'd hate to warp it.

Thanks!

 

[Barry]

Your idea of a light-blasting clean-up will work, and the only other choice is an acid.
Either way, it is not clean enough at this point.

 

[clubairth]

You might consider getting a surface conditioning tool?
Harbor Freight has a real nice one and it goes on sale regularly too. I got mine for $119 and that includes 3 stripping/sanding drums. If you watch for sales this goes as low as $109 but I have only seen that once.

Surface Conditioning Tool

Works like a dream too. Eastwood has a ton of different drums plus an adapter kit to run narrow wheels to get into small places. But they are VERY over priced!
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[robking]

Your idea of a light-blasting clean-up will work, and the only other choice is an acid.
Either way, it is not clean enough at this point.

Thanks Barry, I was wondering about ospho but concerned about leaving acid in those pits. Not to mention containing it to the top of the car. I'm always paranoid it will get places I don't want, won't get neutralized, and then cause adhesion issues.

 

[robking]

You might consider getting a surface conditioning tool?
Harbor Freight has a real nice one and it goes on sale regularly too. I got mine for $119 and that includes 3 stripping/sanding drums. If you watch for sales this goes as low as $109 but I have only seen that once.

Surface Conditioning Tool

Works like a dream too. Eastwood has a ton of different drums plus an adapter kit to run narrow wheels to get into small places. But they are VERY over priced!
.
.
.

I have looked at that HF one a couple of times and almost pulled the trigger. Unfortunately I don't think it will have much better luck getting to the bottom of all those tiny pits. I said shallow above but in reality they are little craters.

I did put a HF grinder vacuum attachment on my angle grinder with the 3m clean/strip disc, that helped with the mess quite a bit.

 

[shine]

use starblast to blast it with. very fine and gets the pits clean. stay 45 degrees and it will be fine.

 

[robking]

use starblast to blast it with. very fine and gets the pits clean. stay 45 degrees and it will be fine.

Thanks Shine, reading up on that it sounds a lot better than the medium grit glass from NT. Do you know if any of the big guys (like Grainger) carry it? Been googling but not getting anywhere. Worst case it's a four hour round to blast-it-all.

 

[shine]

it is a dupont product.

 

[JimKueneman]

it is a dupont product.

My local place has said they can’t get Starblast anymore. Are you having issues?

 

[Chris_Hamilton]

Persoanlly I use the crushed glass from Northern and it works very well IMO. Cheap too.

 

[JimKueneman]

Persoanlly I use the crushed glass from Northern and it works very well IMO. Cheap too.

So I did do a comparison of the glass vs Starblast. I am still a bigger fan of Starblast mixed with large slag. It cuts black rust pits better with my home setup. It can be swept up and recycled till it turns to dust and still cuts great. Just my opinion

 

[robking]

Persoanlly I use the crushed glass from Northern and it works very well IMO. Cheap too.

Thanks Chris, I did have good luck cleaning up a fender with the crushed glass from NT, similar damage to this.

I do have one other quick question, the rest of the body is down to metal with the 3m clean/strip disc. My original plan had been to go back over it with 80 on a DA to get a scratch and epoxy. Would it makes sense to go ahead and epoxy everything else but the roof then blast / epoxy it? Or blast/epoxy the roof first? I won't lie I tend to over think stuff like this...

 

[Chris_Hamilton]

Thanks Chris, I did have good luck cleaning up a fender with the crushed glass from NT, similar damage to this.

I do have one other quick question, the rest of the body is down to metal with the 3m clean/strip disc. My original plan had been to go back over it with 80 on a DA to get a scratch and epoxy. Would it makes sense to go ahead and epoxy everything else but the roof then blast / epoxy it? Or blast/epoxy the roof first? I won't lie I tend to over think stuff like this...

I would blast first. Only reason to epoxy everything else first is if it was going to sit a long time before you could do the roof.

 

[chevman]

Also depends on environment and weather conditions. The cool nights we are having here in MI now are not good for bare metal.