Surface Prep

Materials


Popular Sandpaper Grits Explained


36 Grit -
If you don't count grinding discs the roughest paper I use is 36 grit. I use it in two configurations 2 3/4" X 17 1/2" and 8" round disks. This paper is used after fillers are cheese grated flat in order to achieve a level surface that is ready for polyester putty.

40 Grit -
I buy this is small quantity to use very seldom for cutting down fillers that I want to have less of a scratch in prior to the next step. A couple of sheets lasts me a long time because I rarely use it.

80 Grit -
This is found in my shop in 6" discs for the DA, 8" disks for my disk sander, 2 3/4" X 17 1/2" for the long sanding board and 2 3/4" x  25 yard roll of Stick-It paper. The roll is the best thing since sliced bread as far as I'm concerned, I use it on 4" and 8" blocks, on tubes for sanding in curved areas and it's great just to tear off a 3" piece and fold it in half to do little jobs with by hand. On the DA this 80 grit is used for cutting out scratches left from doing body work feathering out chips in paint. On the 8" disk sander it can be use for stripping off paint without tearing up the metal like 36 will. On blocks and boards it's the perfect grit for sanding polyester putty before your 2K or primer/filler is sprayed on.

220/240 Grit -
6" discs, 9" X 11" sheets (Dry & Wet), 2 3/4" X 25 yard roll...the disks are used on the DA to remove 80 scratches and finesse the feathering process. This grit has faded out over the last 15 years and is used much less in preparing the vehicle for paint because today's paint materials don't need this heavy of a scratch to bond to the surface and this heavy scratch will show through many bc/cc colors.  However, if I'm planning on RE-coating with primer a second time I'll make fast work of the first primer coat with a properly folded piece of 220 wet. Proper paper folding can make the wet or dry paper last much longer but I digress.. I use the roll paper the same as the 80 on blocks and boards to achieve flatness and torn into smaller pieces for hand use.  Right before applying my 2K primer I'll sand my filler, very lightly with 220 dry in order to soften the 80 scratches slightly.

320 Grit -
6 " discs and 9" X 11" sheets (Dry & Wet).. This is a must have for sanding under single stage paint that you plan on buffing or single stage paint that is a lighter color and less expensive paint job. Primer can also be cut with this grit quickly then followed by 400 wet that can be painted over by almost everything. I usually use this dry to sand a vehicle for overall painting. The same grit dry will leave LESS of a scratch than a wet paper.

400 Grit -
9" X 11" sheets (Dry & Wet)... I rarely use this material dry but I will sand a vehicle for an overall that will be painted a color that may easily show sand scratches (like a bc/cc silver) with 400 wet. Using this grit dry is a hassle because it fills with dust so quickly but wet I use this in "properly torn and folded" sheets to sand primers before painting. This is about the most coarse grit that you will want to sand under most bc/cc with in a wet paper. 

600 Grit -
9" X 11" sheets (Wet)... Another handy grit that can be used if you must make corrections in soft paint or you're running out of paint and need to re shoot a panel you might hit it with 600 wet first.

1200/1500/2000 Grits -
5 1/2" x 9" & 9" X 11"(wet sheets) and 3M color sanding film in 6" discs. These are for color sanding after the paint is applied and hardened and is followed by buffing compound.  Before 3M came along with the sanding film you had to sand the entire vehicle by hand, which could take an entire day or more,  now with the 3M discs, an interface pad and the proper DA you can cut that labor time in half, to say nothing of all that arm motion.

Sandpaper Grading Systems

The size of the grit on sandpaper is measured using several different systems.  In the USA we use the CAMI (Coated Abrasives Manufacturer's Institute) system.  In Europe they use the FEPA (or P grade system).  There is also measurement  in inches and microns.  I've put a conversion chart on this site in order that you get the sandpaper you want and/or you can judge the sandpaper you have.


Sanding Materials
Quantity and Pricing
Can be found in our shopping cart located

Here


Grinding Products
Quantity and Pricing
Can be found in our shopping cart located

Here


Small quantity kits are at the bottom of this page


Stripping 
With a Disk Sander

My Favorite way to strip a vehicle in my shop is to remove the buffing pad from my buffer/disk sander and install a Hook and Loop pad and an 80 grit Norton sanding disk. I can strip an entire vehicle in one day without the mess of liquid stripper getting into places it shouldn't causing problems later.

This process works best with a variable speed buffer because you can strip
the paint off quickly without the quick chance of heating/warping the metal.

Using this method you must wear breathing and eye protection because of the dust generated.


 Norton 80 Grit Disks #23591 is a box of 25

This Strip Kit can be priced and/or purchased from our
Shopping Cart and is located Here


Sandpaper Kits

In an effort to aid you in getting the right materials to do a job I've put together a number of KITS that should be able to get you through a job without having to over buy or guess at what materials you need to complete the job. 

Kit #1 - Painter's Small Variety Kit

Kit 1.jpg (23112 bytes)

Click Image to Enlarge

The following items are included in Kit #1

 
     5 Sheets of 36 grit Long Board Paper
     5    "         "  80  "       "          "          "
     5    "         " 320 No Fill Paper  (white)
     5    "         " 400  "       "     "           "
     5    "         " 320 Wet Sanding Paper (black)
     5    "         " 400    "         "            "          "
     5    "         " 600    "         "            "          "
    10   "        " 1500  "        "            "          "
     1   4" Plastic Squeegee (spreader)
     2   Detro Anti-Static Tack Rags

Price or Order #K1 Here

Kit #2 - Body Worker's Small Variety Tool Kit

 

Kit 2.jpg (32038 bytes)


The following items are included in Kit #2
        

    1  10" Cheese Grater Blade
    5  Sheets of 36 grit Long Board Paper
    5    "         "  80  "       "          "          "

    1   Long Sanding board
    2   Double strap dust masks
    1   4" Sanding Block
    3   Pair of Latex Gloves (large)
    1   Blow gun
(not shown)
    1  4" Plastic Squeegee  (spreader)

Price or Order  #K2 Here

Norton8620roll80.JPG (8357 bytes)

Some of the most used sandpaper grit in the shop is 80 grit and one of the best ways to stock it is in the 25 yard  "Stick-It" roll Available in 3M  #2599 for $33.50.

Other grits in 30 yard rolls include
100 grit 3M #2598
120 grit 3M #2597
and 45 yard rolls are available in
150 grit 3M #2596
180 grit 3M #2595
220 grit 3M #2594
240 grit 3M #2593
320 grit 3M #2591
400 grit 3M #2590

Pictured above is the Norton 80 grit roll which we also carry but prices are not yet available.
A 2 roll dispenser for the roll sandpaper is also available

These handy rolls of sandpaper are available Here

 


Grinding

Grinding is needed to for several reasons but in most cases you are removing surface contaminants like paint or rust and/or prepping the surface for further work. The tools below are the ones that we use for most grinding operations in our shop.

Caution
The grinding operation, like other tasks, is very dangerous and should be done using the proper eye protection.  It's well worth the time to wear protective goggles.


 

One of the best tools for grinding metal in preparation for filler is the
Norton Speed Loc Disk

The Speed Loc system can be used in a
drill or an angle grinder with excellent results.

Click Image to Enlarge

Norton 3inch disks.jpg (30971 bytes)



Chicago Pneumatic Angle Grinder
#CP875
CP875grinder.jpg (20883 bytes)


 

Find grinding items Here


This is a great product for guiding you to smooth body work.
You apply it with the powder puff-like applicator and as you
sand you see the high and the low spots in the guide coating.
(This product can also be used for wet sanding)

Pricing or ordering can be done HERE


Detro   (anti static) Tack Rags

Detro tack rags.jpg (22588 bytes)

  A box of 12 Detro Anti Static tack rags

These are the best inexpensive tack rags we've found, they removed dust and
help to control static

You can price or purchase them Here

Disclaimer: The ideas and methods described in this web site were developed under unique situations. Since these situations cannot be duplicated, you may get different results. Use and application of any of the site's content is at the user's own risk.

All information on this site is the property of Stuart's Autobodystore.com and may not be reproduced without prior written permission.