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Grand73Am
12-30-2013, 12:33 AM
I recently sprayed a whole car with bc/cc, using 3 coats high solids clear. I got more orange peel than I wanted in places, but using my Hutchins finishing sander with interface pad, I flattened the paint with 1200 finishing film discs. I followed that with some 1500 wet with a sponge pad by hand. Normally at this point, I'd compound with a wool pad, and finish with a machine glaze on a soft pad.

But, this car has a lot of body side style lines and edges that I don't want to risk cutting through with a coarse pad. Also, I want to remove as little clear coat as possible from now on. So I was thinking of continuing to wet sand by hand with finer grits to have more control, to lessen the chance of cutting through an edge and maybe remove less material than compound on a wool pad would. I thought if I could finish with 3000, I could use a finer compound on a foam pad, and it would take less compounding to shine it up. I have some Presta Ultra 2 step compound that's supposed to remove 3000 with a foam pad.

My question is from 1500 wet, what grades of paper would get me to 3000. in other words, will 3000 remove 1500 scratches, or do I need to do a 2000 or 2500 or both, in between? I was thinking that fewer sanding sessions would preserve clear if possible. What do y'all think? Thanks!

style
12-30-2013, 01:56 AM
by hand id use Norton 1500 on a soft block and a spray bottle with water to rinse it then jump to 2500 Norton the same way and use a Norton ice stage 1 pad with sure finish on low speed to remove the sanding marks then Norton ice stage 3 pad with sure finish to jewel the surface...

if your so worried about clear why not sand it with 1500 and flow coat it..

Grand73Am
12-30-2013, 09:30 AM
Thanks for the advice. Sounds like that works. I should say that I already have supplies, so rather try using what I have if possible.

I'm not interested in painting it again, and should be able to buff what I have. Just looking for a less aggressive way to get there than what I've done in the past, which was compounding it with wool after 1500.

Would like to hear more ideas. I'm already at 1500, so just wondering what's the least aggressive way to get it to 3000, so I can use the materials I have to buff from there. I have Presta Ultra 2 compound, which is supposed to remove 1500 scratches with a wool pad. It also says it removes 3000 scratches with a white foam. I'm wondering if I'll be removing less paint by just going ahead an buffing with wool on the 1500, or if sanding to 3000 and buffing with foam? Or maybe there's no significant difference in removal of material either way?

If there's a less aggressive compound that removes 3000 scratches with a rotary machine and foam pad, I'd be interested to hear about it. Apparently SureFinish is one of those? I have white compounding foams and black polishing foams, so would like to use the foams I have. I have some 2000 paper. Would 3000 paper take out 1500 or 2000 scratches for example?

Might seem like a vague or obvious question, but mainly just trying to get ideas for taking it from 1500 with the least material removal, whether it be finer sanding or just compounding from where I am. I know I have to be careful around edges and use tape in some cases, but it's easy to knock tape off too.

Len
12-30-2013, 09:56 AM
We normally use 1500 Trizact on a random orbital sander to remove orange peel then we switch to 3000 Trizact on the sander to remove the 1500 scratches before we polish using Sure Finish or Wizard's Mystic Cut. If we must sand by hand we will normally use 1500 wet then 2500 wet before polishing.

The Sure Finish is a little more gentle than the Mystic Cut but both produce about the same result. We keep the pad wet as we polish using a spray bottle and we dampen the pad before we start buffing. Normally we do all our buffing with the Sure Finish orange foam pad but we also use a Sure Finish black foam pad on soft/dark colors. A good variable speed buffer with proper polish and pads are a must for optimum results.


Buffing Tips Link (http://www.autobodystore.com/buffing_technique.shtml)


http://www.autobodystore.com/sandingchart.jpg
Color/Clear Sanding Link (http://www.autobodystore.com/ccsanding.shtml)

http://autobodystore.net/Merchant2/graphics/00000001/sfstuff.jpg
Pad Link (http://autobodystore.net/Merchant2/merchant.mvc?Screen=PROD&Store_Code=ABS&Product_Code=SFPADS&Category_Code=T2)

http://autobodystore.net/Merchant2/graphics/00000001/wiz11048.jpg
Polishing Materials Link (http://autobodystore.net/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=ABS&Category_Code=M3)

Grand73Am
12-30-2013, 10:43 AM
Thanks for the great advice and pictures Len! That gives me some things to try. My Hutchins finishing sander is a gentle, short stroke, orbital which has worked well for many years for using finishing film discs with an interface pad. And I've had my Makita variable speed sander/polisher for many years too. I've mostly sanded to 1500 in the past, using finishing film, with occasionally using 2000 wet. Then compounded with a Schlegel, with foam pads to follow.
So I haven't had experience using 2500 or 3000, so didn't know what to expect from them. And I'm not up on the latest compounds, so didn't know what works best on paint sanded to that level of fineness. So, this info helps greatly. I'm going to experiment with this info on a separate flat panel where the clear is heavier to develop a procedure. The sides of the car are my worry, since I didn't put the clear on as wet to avoid running, which I didn't run, but am concerned about film thickness. So I want to go as light as I can on them. Those orange and black rounded edge foam buffs look like safer buffs to use. Thanks again! Steve

Len
12-30-2013, 03:25 PM
Thanks for the great advice and pictures Len! That gives me some things to try. My Hutchins finishing sander is a gentle, short stroke, orbital which has worked well for many years for using finishing film discs with an interface pad. And I've had my Makita variable speed sander/polisher for many years too. I've mostly sanded to 1500 in the past, using finishing film, with occasionally using 2000 wet. Then compounded with a Schlegel, with foam pads to follow.
So I haven't had experience using 2500 or 3000, so didn't know what to expect from them. And I'm not up on the latest compounds, so didn't know what works best on paint sanded to that level of fineness. So, this info helps greatly. I'm going to experiment with this info on a separate flat panel where the clear is heavier to develop a procedure. The sides of the car are my worry, since I didn't put the clear on as wet to avoid running, which I didn't run, but am concerned about film thickness. So I want to go as light as I can on them. Those orange and black rounded edge foam buffs look like safer buffs to use. Thanks again! Steve

If you sand with 1500 then with 3000 the surface will already have a slight gloss to it and buff up very quickly.

Grand73Am
12-30-2013, 04:32 PM
Okay, that's good to hear. Thanks! :)

Grand73Am
12-31-2013, 08:41 PM
If you sand with 1500 then with 3000 the surface will already have a slight gloss to it and buff up very quickly.

I've been reading some of the older posts and noticed that the Trizact 3000 disc was being used on the sander with a little water spray? Is it always used wet? I guess it wouldn't last long using it dry?
Since they are expensive, does using it wet make one last a long time? And when sanding, does the 3000 disc require some "rinsing" occasionally?

Len
12-31-2013, 09:36 PM
I've been reading some of the older posts and noticed that the Trizact 3000 disc was being used on the sander with a little water spray? Is it always used wet? I guess it wouldn't last long using it dry?
Since they are expensive, does using it wet make one last a long time? And when sanding, does the 3000 disc require some "rinsing" occasionally?

It must be used wet so that the dust floats away from the disk's grit. The 3000 grit Trizact can probably remove 1500 scratches from several panels when it's used properly. Five disks is usually enough to rid most complete cars of 1500 grit scratches. Use a spray bottle to keep the surface wet as you sand.

Grand73Am
12-31-2013, 09:59 PM
Alrighty then. Now I know what to do. :) Thanks!