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So...I can get some nice sanding blocks through Grizzly or I can make my own. The Grizzly blocks have a felt pad on the base. I'm not sure if it can be easily removed.

I'm under the impression that all my flat sanding is best done with hard, flat blocks.

I can see how a felt pad would make better overall contact....but I can also see it rounding off edges.

What's your experience?

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

To flatten things a flat hard pad works best. I've glued pieces of hpl on the bottoms of some of my electric pad sanders to use them for flattening things. Felt will wrap itself around the work and cork is somewhere in between. Having a collection of different backing pads and sanding blocks allows you to use the right one for different jobs.

I would say that it depends on the felt. There's hard felt and there's soft felt, like material. You can even buy felt blocks that can be used as sanding blocks, and they are pretty hard. Some folks use felt blocks and rottonstone to rub out finishes.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Stu,

I use hard blocks. It's the best way for me to get a truly flat surface. It seems to me that finishing is a lot easier when I start with a rigid block during pre-finish prep and early finish levelling, then move to more cushy pads as I progress through the later stages. Works for me. YMMV.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

I'm with Pat on this. I use little blocks made from MDF during the prep before finish, and in the early finish stages. Then use softer blocks after moving to grits over 600 grit. So you can still use those felt blocks, just not during the prep stages. I actually use a cork lined mdf block at the next stage(make these myself by gluing them on with spray adhesive), then the final stage of finish I use Japanese Erasers(keishi gummu), as I like the consistency better then the trapezoid american erasers. But have use american erasers too. Just cut off the 2 ends to make little blocks and wrap your high grit sandpaper around them...only used for wet sanding. Hope that helps!

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Tracy
http://www.luthiersuppliers.com

I have some felt backed saning pads from 3M that hold a roll of stick-it on the front. They are absolutely fabulous for sanding during finishing, and clean fresh abrasive is a snap. I like a block lined with 1/4" cork for a lot of final sanding prior to finishing and only use a hard solid block for initial leveling.
Brian

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Clay - if I may ask, what is "hpl"?

It seems every little nook and cranny of my shop is being taken over by cauls and sanding blocks. I've got sanding blocks for every occasion -- most are stikit abrasives stuck to mdf or plywood, but the forms they take are endless -- flat, concave, convex, cylindrical, dainty, burly, teardrop-shaped, reverse-scalloped, beveled, T-shaped, tall and skinny, short n' fat, you name it. For finish work, it's a rigid block for initial leveling down to 600, then I switch to Micro Mesh with the foam block. Take that up to 12,000, then it's just a few minutes on the buffer.

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Mountain Song Guitars www.mountainsongguitars.com

Bruce Sexauer once gave us a tip (at one of our NCAL meetings) that the best sanding "block" material he'd ever found was rectangles cut from cheap flip-flops!

I tried it - bought some $2 size 11's and cut them up on the bandsaw - they work great! YMMV.

+1 for using custom sized MDF blocks as needed also.

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

+1 on the erasers. I use the white, rectangular drafting erasers. Great for small areas like headstocks, around the heel and so on.

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Steve Smith
"Music is what feelings sound like"

2000 on the Micro Mesh scale? There's 1800 and 2400, which I'd estimate is around 1000 grit on the P-scale. There's no way I could buff those scratches out. I could see stopping around 4000 or 6000, but no sooner. My experience is with EM6000 waterborne lacquer.

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Mountain Song Guitars www.mountainsongguitars.com

You need both hard and soft blocks, and some in between. Depends on which part of which job you are on.

It would help sanding discussions a lot if people would specify which grit system they are in. I've found that a lot of folks (including a very well-known luthier) are mixing grit systems without knowing it. FEPA ("P") system grits are numbered roughly twice as high as equivalent CAMI (old American system) grits. And there are also differences in the grit tolerance. Then there are those other systems and non-paper materials that don't exactly translate.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

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High pressure laminate. You may know it as Formica.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Ah...thank you Brian.

why do they have to do that with the grits? Jeez. As if things weren't complicated enuf.

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

Hi Charlie,
Sorry I didn't check back to this thread sooner. As Brian mentioned it is "Formica" type materials. It can either be spray glued to the backing pad of the sander, or if you use sections of sanding belts, glued to the back side of the belt. The belt sander method allows you to use the "hard pad" for your initial flattening, then switch back to the original surface for the final sanding.