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Brad, what model number?

I have used the Formula 2050 Blade and Bit Cleaner to clean belts on the sander. I put a couple layers and cardboard on the feed belt and pour sparingly on the belt and brush gently with a wire brush. It does ok. I read about dunking the belts in acetone and hanging to dry, but they got so curly in the process they were unusable.
Kent

I agree - fast feed along with a light cut equals lower surface temps which means the resins aren’t melting, loading the paper. This is true to a point - there is a point where the abrasive can’t keep up with the cut depth and feed speed, causing heat, or having the drum over run the desired cut depth causing the structure to deflect creating a poor surface finish and unnecessary stress on the machine. On my machine a maximum of an 1/8 turn at a little over half speed is my sweet spot.

Cheers, M

... On my machine a maximum of an 1/8 turn at a little over half speed is my sweet spot.

Cheers, M

What I do as well with my 10-20 running 80 grit.

I need to try 120, sure would be easier to sand later.

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Steve Smith
"Music is what feelings sound like"

I use 100 grit—faster than 120 without the canyons caused by 80. Usually, 1/8 turn and the fastest feed speed works unless the piece is wide enough that the drum loads. Keeping the cut light enough that the machine doesn’t load at the fastest feed speed seems to work for me.

its called matching the feed rate to the cut rate
I use 60 grit, I have a wide belt but when I had a drum I use 60 grit , light passes as fast as it would go. Once you build up heat your done. As a machinist I can tell you this. As you work you make heat. You want that to be in the chip , not the tool ( paper ) or the work but in the dust.
Yes some is so resinous you get glazed but take about .010 cut as fast as your machine can go.
If that builds up then cut less.

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John Hall
blues creek guitars
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You Don't know what you don't know until you know it

I agree with what has been said, but will add that for resinous woods a small benchtop planer with sharp blades can be helpful to bring the plates to near final thickness. Because of the small diameter of the cutterhead the infeed and outfeed rollers on these planers are closer together than they are on large planers and do a better job of holding thin plates down and keeping them from being sucked up into the cutterhead. As with most things there is a limit to what they can do, but for a small production shop they may save enough time and aggravation (and expense, says the cheap guy) changing belts to make buying one worthwhile (I have two).

I'll have to try that next time, I definitely was not running the feed belt fast though I do take small 1/8th turn cuts.

Out of curiosity, several of you folks have mentioned depth of cut in fractional turn of the depth wheel. What does 1 rev or 1/8 turn amount to in thousands of an inch? Wondering what you are able to take off in a pass.

Depending on grit size I usually try either 0.005-0.010 per pass and see how it goes.

Having a DRO on the drum sander is a help. I use a dual drum machine but not in the conventional way. I found trying to adjust 2 drums to work together with 2 grits on problem woods was futile.

However having a courser grit on the lead drum (80) and finer on the second (100-120) was still an advantage. On my Supermax I can adjust the second drum in or out of action and it saves a lot of strip changes.

Earlier I mentioned I'd tried 60 grit but I looked and it was actually 50 and the blue zircon type. It seemed to leave too many errant deep scratches for me. Might be good for hogging off some birdseye or tight curly wood. I had a roll of blue 36 grit to try - I must have been really frustrated last time I did a batch of backs and sides. Don't think I'll go down that road.

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Brian R, Wood Mechanic
N8ZED

I’m have a SM 19-38 and it says 1/4 turn = 1/64”. I also turn it 1/8 turn and run the belt usually at 70.


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My ProMax 16/32 is also 1/4 turn = 1/64".

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

On my pre-Jet Performax Shop Pro 25, each full turn of the wheel is 3/32”. So, an eighth of a full turn is about twelve thousandths. I have gotten good at nudging the wheel at smaller increments and double passes to get exactly where I want to go, but for normal removal of hardwood thickness before I get close to the target, an eighth of a turn works pretty well. I run the feed at full speed.

Thanks guys so a 1/8th turn is around 0.007". So we are all pretty much in the same cut range of 0.010 or less per pass.

My Supermax table adjusts 3/32 per wheel turn so an eighth of a turn is about 0.012. That's where the DRO comes in handy.

Well, now we know how some of the common machines work. Thanks

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Brian R, Wood Mechanic
N8ZED

I've found a quick wipe with acetone before each pass helps to clean a good amount of oil off the surface of oily rosewoods and helps to prolong the life of the sanding belt. With that said, for especially oily woods, I use 36 grit paper to remove the bulk of material, switch to 100 grit once the material is within .5mm of desired thickness, then scrape clean after finished with the sander. A bit of a pain to change the belt but the time saved with 36 grit is worth it. Certainly better than spending the better part of the day becoming more acquainted with my toothed blade no 4 1/2

I recall the original LMI use to spray their sanding belts with silicone spray and then wipe the wood down with naphtha. On my SM 19-38, I use a crape rubber block to clean the sandpaper before too much resin builds up.