Slack Belt Sander SFPM?

[FredS]

I'm building a slack belt sander for 1"x90" belts. The typical small " belt sanders you see at every tool store run about 3000 SFPM, which is faster than I want to run over my fingers, but I'm not sure what would work best.

Any of you guys who are using such machines know what sort of SFPM your belts are running?

[Archer]

Get a 1750rpm motor, attach a stepped pulley to your motor shaft and drive wheel shaft. Should be good for a range of low speeds. You can harvest motors from dryers etc.

[FredS]

Gee, I never thought of that.

Does anyone know what sort of SFPM is 'comfortable' to work with?

[Archer]

Depends on if you've got shop worn gnarly man hands or desk/computer made, well lotioned girl hands...lol!

The step pulley should give you some room to decide whats comfy. Disclaimer:I am not an expert. I am regurgitating stuff I have read. There are a few posts here on speed, building, supplies, etc. Also wonder about 1" vs. 2" and that "comfy" thing...seems 1" is just thin enough at the right speed to cut a finger off...dunno, just thinking out loud.

[Alan L]

I run my 2x72" slack belt at around 900 SFPM for wood. Faster and it'll burn. The belts will still flay your fingers to the bone if you catch an edge, so you've been warned.

[FredS]

Cool. I can get it down to 900 FPM with the motor and sanding belt drive wheel I have in hand. I may even try for 700 if I can come up with the right combination of pulleys between the two.

[Kenny]

First, the grit your using will make a difference in the speed you need. Lower grits (numerically) can be run faster than higher grits without clogging or burning (the wood, not you). Higher grits need to be run a touch slower. But you may not be running a slack-sander fast enough for it to matter anyway.

I would start somewhere between 700-900fpm, as that would give you a belt with a surface speed of around 9-10mph, which shouldn't be too hard on the fingers.

If you don't have some rugged hands, try a set of these: http://www.rockler.com/product.cfm?page ... mb%20guard

I use them quite often when doing all sorts of stuff, carving, using rasps, power sanding with low grits (40 grit will show bone in a heartbeat). It just keeps your finger tips from getting sore and chewed up. It does make it hard to feel detail, but you have another hand for that.

There are also full gloves available too: http://www.woodcraft.com/Search2/Search ... g%20gloves

I have a set of Kevlar gloves that work well, but again, the tactility thing comes into play.

[Charl]

As far as I can remember (which is not much, my wife can tell you!) mine is more or less at 400rpm. It's fast enough to do the job, but doesn't burn my hands. I can double check if you want to be sure.

[Meanmcqueen]

Fred,
Can you post pictures when you're done? I would love to see one. Thanks.

[Tyler]

FWIW, which is probably very little, I've never heard of a big slack sander for pipe making using 1" belts. Everyone uses 2".

No experience here, so I'm just mentioning that in case you didn't know.

I think the reason for that is that the edges are not your friend. 1" has a lot of edge, if you know what I mean.



Tyler

[bregolad]

I use 1x72 belts, using the lowest setting on the pulley (motor and pulley from a drill press). I have cloth backed 240 grit, and its super gentle. I like the disc sander too much for general shaping, just using the slack sander for real fine tuning. I've never had an issue with my fingers whatsoever, probably because of the gentle grit.

[Charl]

I must be OK then, I use 2' wide belts Seriously, I don't see the need for thinner belts. Like Tyler said, the 1" is asking for trouble. And I use 400 grit on mine.

[FredS]

FWIW, which is probably very little, I've never heard of a big slack sander for pipe making using 1" belts. Everyone uses 2".

No experience here, so I'm just mentioning that in case you didn't know.

I think the reason for that is that the edges are not your friend. 1" has a lot of edge, if you know what I mean.

Tyler

I hear you Tyler. But I'm pretty tight with a dime and I had an old 1" belt sander I no longer used so I'm using the motor, tracking adjuster, and - most importantly - drive and idler wheels from it. If it ends up being a machine I like using, I'll build a real one with 2" belts. But the drive and idler wheels for a 2" belt cost a pretty penny. I understand that edges can do a lot of damage in the blink of an eye an I'll only have about a half inch sweet spot with this thing.

[Alan L]

Narrower belts cut faster for some reason, making it MUCH more difficult to get a uniform surface. I use split belts on my 2x72 grinder for some things, such as getting inside a tight curve. A 1/2" wide 400 grit j-weight belt will cut briar almost like a high-speed chainsaw file, so be careful!

[pipeguy]

I use 2"belts at about 400 sfpm 220- 400 grit boy what a time saver

[the rev]

Was going to make my own slack sander out of a twelve speed bike. My goal is to figure out a way to have all of my pipe making be by hand power. Might help me to get back into the shape I was in when I was fighting

rev

[wmolaw]

Was going to make my own slack sander out of a twelve speed bike. My goal is to figure out a way to have all of my pipe making be by hand power. Might help me to get back into the shape I was in when I was fighting

rev

hmmmm, let me know when you figure out how to pedal the bike and sand at the same time!

Or if you are going to have all the power be by HAND power, then I guess you would pedal with your hands, and carve with your feet!

[the rev]

yes I will be carving with my feet of course

once you get in a rhythm you forget you are peddling, or so my theory goes

rev

[scotties22]

You are supposed to hire some hapless schlep off Craiglist to peddle for you

[the rev]

you applying? if so you better not be a punk rock princess with a heart of coal... my wife doesn't like competition

rev