what are you sanding with ?

[shine]

had a long talk with a young painter about a job he's doing. first thing is the ahole streetrodder has him doing it for almost nothing . he's made all the mistakes. crap for a gun , hard production clear and excessive build each coat. needless to say he has thanewave problems. i asked how he was blocking to see if i could help. starting with 1500 , wrong , using a rubber block , wrong , just read the wrong stuff somewhere.

anyway , i make my own sanding blocks in my wood shop. i also have several made from cardboard tube ( sealed with clear ) . i'm a firm believer in hard blocks with the paper tight. loose paper will sunk into lows while blocking.
what are you doing ?

 

['68 Coronet R/T]

For sanding clear coat I start with a homemade block. It is a piece of Oak 3/4" thick, 1 1/4" wide and about 5" long. Gives pretty good access in most places and when used with lower grits cuts the clear flat. Once I get above 1000 grit I use a Motorguard Soft Block.
Anxious to hear what others are using as I am always looking for ways to improve.

 

[Bob Heine]

I use pieces of red oak (1x-2, -3 and -4) for the flat areas and lengths of various diameter schedule-40 PVC pipe for the concave areas (I slit the pipe and wedge the paper in the slot with a strip of aluminum). For the big convex areas I use a 16-inch Drua-Block board. Not a whole lot of flat areas on a C3 Corvette so I end up using the Dura-Block most of the time.

 

[crashtech]

I use a variety of things, but no matter what the block is, I true my blocks on a thick piece of plate glass that has a piece of sandpaper stuck to it. I figure you can't straighten a panel well with a crooked block.

 

[jcclark]

I find I can sand clear straight even with a soft block if I use a coarse paper like 400 to start with

 

[Senile Old Fart]

Shine, I thought I was the only one that trued their block on the jointer!

 

[Jim C]

Shine, I thought I was the only one that trued their block on the jointer!

no, you got another one. i have trued quite a few blocks on a jointer and if not running them through it i take some psa roll paper and stick it to the infeed table or table saw top and true it that way. the sandpaper stuck down works great for hard foam blocks like durablocks, etc. most of the time i am using 3m blocks. just the the whole design of them. i have an older one that i love. if any of you remember they used to have a black hard rubber bottom with a cross hatch pattern which was great, you can true those. now they have a blue vinyl covered foam which i dont like anywhere near as much. for blocking small areas and runs i have a couple blocks made from corian. works great. large curved panels the mid to long afs boards are nice. small curved panels i like the 3/4" thick durablock. hard yet bendable. oh and for that extra special area you have the round durablock rod which we have named the black dong!!! lol. no one like to use that for some reason. cant figure out why.

 

[Barry]

View attachment 333

I find I can sand clear straight even with a soft block if I use a coarse paper like 400 to start with

I do it the same way, I use a soft pad, sometimes sanded with 600 wet, 1000 wet and then 1500 wet, and then buff, sometimes 800 and jump to 1500.
Done a number with 400 on first cutting and then 800 or a 1000 and finer.
Hard blocks just scare me on fresh clear.
Just never have been good at using a small hard block, lot of times will use a soft pad for finale sanding of primer.

Don't matter how you do it, as long as you can get the result you want.

 

[Bob Hollinshead]

400 for colorsanding scares me to death, I've used 600 to start with but even then it takes a lot to get to the higher grits, 800 works, 1000 works fine if you're using a rigid block with a flat surface and the paper is only one thickness. The clear needs to be locked up fairly good if you're using a block without cushion. I have a good selection of plexiglass blocks that I made just for colorsanding-some have a pattern of 3/8" holes drilled in them for a more aggressive cut. I also have some aluminum and wood blocks, PVC tubing, broom handle, durablocks, rubber blocks, an afs board, pipe insulation, foam-lots of different shapes, sizes and firmness. The first step for me though is to use a flat rigid block to cut out every hint of urethane wave. Here's a test for ya: sand some primer with 400 on a soft pad or durablock-think it's straight and flat? now spray on some guidecoat, take an aluminum or plexiglass block that's been trued to perfection and apply one layer of 600 then sand the panel again-the guidecoat tells the story.

 

[Arrowhead]

Here's a dumb question, why don't they make PSA in higher grits? Maybe they do and I just haven't looked hard enough.

 

[Arrowhead]

Here's a test for ya: sand some primer with 400 on a soft pad or durablock-think it's straight and flat? now spray on some guidecoat, take an aluminum or plexiglass block that's been trued to perfection and apply one layer of 600 then sand the panel again-the guidecoat tells the story.

I know what you mean. For long curved surfaces I use a long flat aluminum strip. about 2" wide. It's flexiable enough to adhere to the large curve, but stiff enough to cut down local high spots and show any gradual low spots you could miss.

 

[crashtech]

Here's a dumb question, why don't they make PSA in higher grits? Maybe they do and I just haven't looked hard enough.

We use Norton PSA longboard in 100, 150, 220, and 320. Are you looking for finer than 320?

 

['68 Coronet R/T]

3M Gold 400 grit I think is the finest available in PSA rolls.

 

[Bob Hollinshead]

I have some longboard psa paper in 1500 I'll be experimenting with soon.

 

[Arrowhead]

yea, for wet sanding it would be nice to stick 1000 through 2500 on a block instead of trying to hold it. Plus, paper get wasted by having to wrap it up the sides. And every now and then, it can grap and wrinkle the paper and you get scrathes. Maybe the glue won't work wet, I don't know.