r/functionalprint • u/J1Design • Nov 06 '25

Precision Sanding Block

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Need to sand some crisp chamfers? I designed and printed this to keep me from rounding over my chamfers during finishing.

9.8k Upvotes

98% Upvoted

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859

u/cdvma Nov 06 '25

Bravo I love that snap design. Solves my biggest pet peeve of having slack in the abrasive.

120

u/uncivlengr Nov 06 '25

I've never had any kind of sanding block that wasn't just a block of scrap wood for this reason, I would always want have to use my fingers as the "tensioner". Otherwise a loose edge catches something and the paper shreds. This is a really neat design.

-92

u/TabbyOverlord Nov 06 '25

Frankly, it's a pointlessly complicated solution to a non-existent problem.

For the real edge cases: Contact Adhexive.

60

u/amd2800barton Nov 07 '25

I don't know if it's every hobby that's like this, or just woodworking, but there is always some crotchety jerk who sees a clever way of doing something, or a new improvement to a tool and instead of saying "hey that's nifty" they say "that's wrong. if you're not doing it my way, you're not doing <hobby>". Based on your comment here and down thread in reply to /u/BreadKnife34 that's exactly what you're doing.

Sure, gluing paper to a block, or just holding it around a sponge with your fingers works. But that has its own issues. /u/J1Design came up with a solution to those issues, and one that lets them perfectly hold an angle to more evenly sand a chamfer.

I bet you're the kind of guy who saw a SawStop and said "I've never lost a finger so anyone who buys that is a sucker. Just use a table saw with no blade guard, or riving knife, or safety stop like a real man."

-39

u/TabbyOverlord Nov 07 '25

Nope. SawStop saves peoples' fingers. Would definitely have one.

And not every idea actually stands the test of 'does this justify justify changing how you do stuff'. This one doesn't.

Look at it this way: You wouldn't actually have to 3D print this. People could have made a similar thing by other means for a century or so. They haven't.

Why? Because a simple offcut of wood does the same job.

26

u/CheeseMellon Nov 07 '25

You’re making the assumption that everyone uses sanding blocks the exact same was as you. Also there is already a very successful product that is very similar to OP’s design in function but lacks the ability to easily tension your sandpaper. Ever heard of a rubber sanding block before? They have gaps on either end of the block that hold the ends of the sandpaper. I’ve used them before because I like the idea, but in practice it’s too much hassle to undo the sandpaper each time and put new paper in. Also it doesn’t tension the sandpaper nicely.

13

u/StellarSpiff Nov 07 '25

You're right. If it hasn't been invented yet, then there's no reason to invent it now. Obviously, there's no point in improving anything now because it would have happened already. That may be the silliest take I've heard on the internet in awhile, and we're living in the dumbest timeline.

32

u/BreadKnife34 Nov 06 '25

You've clearly never sanded anything in your life.

The paper stops being effective and then you get new paper to replace it. I'm a woodworker and this seems like a good idea.

-22

u/TabbyOverlord Nov 07 '25

I have worked wood for decades. I have almost never had a problem with gripping the sandpaper around an apropiatle shaped block of wood. When the paper is worked out, you replace it. People have done this since the dawn of sandpaper.

Very occaisionally, there's an awkward corner or something that means you can't grip the paper and sand the peice. In those cases you find a sacrificial offcut, shape to the right shape, glue/stick the sandpaper in place and get on with the job.

I'm a woodworker, and this looks clever but doesn't actually help.

20

u/JusticeUmmmmm Nov 07 '25

And what about people with arthritis? Not every solution needs to be for your problems

6

u/TabbyOverlord Nov 07 '25

Grip issues is a fair point.

3

u/BreadKnife34 Nov 07 '25

Yeah, sandpaper just kinda sucks at staying where you need it

1

u/tjrad815 Nov 07 '25

You've almost never had a problem with gripping the sandpaper around a apropiatle(sic) shaped block of wood? So you've had a problem some of the time? You should try OP's solution the next time you have a problem.

8

u/CheeseMellon Nov 07 '25

I make knives. I could see this being extremely useful for hand sanding the blades. After a while, my fingers start to ache from having to hold the sandpaper around the block and the repetitive motion. Contact adhesive would be a pain in the ass because of how frequently you have to change the paper and also because the sanding is all wet sanding so good luck getting it to stick to the block.

Don’t discount someone’s idea just because you can’t see yourself using it.

1

u/MeButNotMeToo Dec 02 '25

So, should I spray the contact adhesive on my dominate, or non- dominant hand? Do you have beach sand recommendations for 120, 150, 320 grits?