Paint & Body Work Custom Painting | Panel Repairs & Replacement

sanding bumper????

Old Jul 24, 2007 | 07:22 PM
  #1  
therobman's Avatar
Thread Starter
TECH Fanatic
iTrader: (39)
 
Joined: Oct 2006
Posts: 1,766
Likes: 2
From: Nyc
Default sanding bumper????

my stupid sis backed into my bumper and i gotta get it repainted im goin to sand it myself.. what gritt should i start off with and what should i end of with and sand just to the black right ?
Reply
Old Jul 24, 2007 | 09:07 PM
  #2  
johnson7454's Avatar
Launching!
iTrader: (3)
 
Joined: Nov 2006
Posts: 274
Likes: 0
From: cs/bryan, tx
Default

did it spider crack the paint?? did it leave damage??? If not then 400-600-800
Reply
Old Jul 24, 2007 | 11:27 PM
  #3  
Pheonix's Avatar
TECH Resident
iTrader: (16)
 
Joined: Feb 2007
Posts: 802
Likes: 0
From: Baytown, Tx
Default

I would bust out the d/a if it spidered on you, but i dont think you would have that off hand. I would use something coarse like 80grt to get down to it with the d/a even by hand then 400, 600.
Reply
Old Jul 25, 2007 | 12:14 AM
  #4  
snake charmer's Avatar
TECH Fanatic
iTrader: (118)
 
Joined: Sep 2004
Posts: 1,510
Likes: 1
From: The south
Default

give usmore details on the damge . as far as grit ilike tostay fine so 600+ would be good .
Reply
Old Jul 25, 2007 | 01:52 AM
  #5  
therobman's Avatar
Thread Starter
TECH Fanatic
iTrader: (39)
 
Joined: Oct 2006
Posts: 1,766
Likes: 2
From: Nyc
Default

yea all spidercracks deff have to sand down the hole thing
Reply
Old Jul 25, 2007 | 12:45 PM
  #6  
therobman's Avatar
Thread Starter
TECH Fanatic
iTrader: (39)
 
Joined: Oct 2006
Posts: 1,766
Likes: 2
From: Nyc
Default

bump!!!!!!!!!
Reply
Old Jul 25, 2007 | 01:49 PM
  #7  
Camaroholic's Avatar
TECH Senior Member
iTrader: (1)
 
Joined: Nov 2001
Posts: 6,449
Likes: 1
From: Waco, TX
Default

I'm a wuss when it comes to sanding urethane, 80 grit's pretty danged aggressive on a DA. I'd use 180, take it down to where the spidercracks are gone.
Reply
Old Jul 25, 2007 | 02:13 PM
  #8  
onefastss223's Avatar
On The Tree
iTrader: (14)
 
Joined: Jul 2005
Posts: 181
Likes: 0
Default

I use 180 for spider cracks and then come back with 400 and some superfine around the edges. Sand until it looks like the orange peel is going away. A d/a will turn this into a 10 min job.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-1

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-2

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-3

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-4

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-5

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-6

10 Camaros You Should Never Buy

 
story-7

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
story-8

Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

 Brett Foote
story-9

10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever

 Verdad Gallardo
Old Jul 25, 2007 | 02:48 PM
  #9  
johnson7454's Avatar
Launching!
iTrader: (3)
 
Joined: Nov 2006
Posts: 274
Likes: 0
From: cs/bryan, tx
Default

Originally Posted by onefastss223
I use 180 for spider cracks and then come back with 400 and some superfine around the edges. Sand until it looks like the orange peel is going away. A d/a will turn this into a 10 min job.
going from 180 to 400 will not get the sanding marks out...always go to next size until you reach the desired level...220-320-400...etc..
Reply
Old Jul 25, 2007 | 07:47 PM
  #10  
redramair98's Avatar
TECH Enthusiast
iTrader: (74)
 
Joined: Nov 2006
Posts: 544
Likes: 0
Default

for spidering use 150 on a da or block it by hand, just takes a bit longer, feather around and over all the 150 scratches with 400, then high build prime it sand until smooth, if you still get fuzz coming threw in the plastic reprime it, then to prep for paint you can use 400 to 600 if you want to recolor the whole thing, or use 1000 over the whole bumper to scuff the clear, to reclear the bumper, hope that made sense to you
Reply
Old Aug 7, 2007 | 01:14 AM
  #11  
therobman's Avatar
Thread Starter
TECH Fanatic
iTrader: (39)
 
Joined: Oct 2006
Posts: 1,766
Likes: 2
From: Nyc
Default

im goin to sand it tomorrow i have a d/a so bacially i sand all the spidercracks down to the black with 150 feather around it then use 400 and scuff the rest of it??????????
Reply
Old Aug 7, 2007 | 10:22 AM
  #12  
therobman's Avatar
Thread Starter
TECH Fanatic
iTrader: (39)
 
Joined: Oct 2006
Posts: 1,766
Likes: 2
From: Nyc
Default

???????????????????????
Reply
Old Aug 7, 2007 | 10:35 AM
  #13  
Camaroholic's Avatar
TECH Senior Member
iTrader: (1)
 
Joined: Nov 2001
Posts: 6,449
Likes: 1
From: Waco, TX
Default

I would reprime the whole thing with epoxy primer after sanding (your 150/400 should be fine), let that set up, sand the epoxy with 600 wet, and then shoot. The epoxy will seal everything below it.

I must retract my earlier statement about 80 grit though. I started sanding on my Fiero this weekend, and started with 180 on the DA. After going through 2 discs in about 3 square feet (the Mirka gold paper was loading up), I switched to 80 grit. I was able to do most of the rest of the bumper with 1 sheet of 80. Yeah, I am being VERY careful around any molded transitions (points, ridges, etc), because they'd be very easy to burn off. But for the 5 layers that I have to sand through (original silver paint, gray build primer, green sealer, silver paint, dark silver paint), the 80 grit was the only way to fly.

150 will work fine for a smaller (1 sq ft) area though.

After I knock all this junk off, I'm going back with a coat of epoxy primer, wet sanding that with 600, and then spraying the base (Viper Blue) and clear.
Reply
Old Aug 7, 2007 | 12:32 PM
  #14  
02gtp4now's Avatar
TECH Junkie
15 Year Member
iTrader: (7)
 
Joined: Oct 2006
Posts: 3,748
Likes: 0
From: lebanon,mo
Default

Originally Posted by Camaroholic
I would reprime the whole thing with epoxy primer after sanding (your 150/400 should be fine), let that set up, sand the epoxy with 600 wet, and then shoot. The epoxy will seal everything below it.

I HOPE YOU MENT TO PRIME THE WHOLE AREA HE WORKS, NOT THE WHOLE BUMPER IT WOULD BE A WASTED OF TIME AND PRIMER TO PRIME THE WHOLE COVER
Reply
Old Aug 9, 2007 | 11:28 AM
  #15  
GoatChzLS1's Avatar
11 Second Club
 
Joined: Apr 2007
Posts: 63
Likes: 0
From: Des Plaines, IL
Default

If its not to late I would suggest 220 on a da until the spider cracks are gone or very faint. Then progress to 320 feathering it out 6 inches beyond the 220 are. Then use 500 on the whole bumper. After that you should get a product called KOMBI putty that is used to fill in small scratches and sand marks. When that has dried use 600 wet and a flexible sanding block to remove the extra putty. Hope this helped
Reply


Thread Tools
Search this Thread

All times are GMT -5. The time now is 02:42 PM.

story-0
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-1
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-2
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-3
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-4
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-5
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-6
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-7
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE
story-8
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

The world was a better place when it was still around.

By Brett Foote | 2026-01-23 09:20:37


VIEW MORE
story-9
10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever

Slideshow: The 7.0-liter LS7 was designed for absolute cutting-edge performance.

By Verdad Gallardo | 2026-01-07 18:36:00


VIEW MORE