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Yup. ONE pass with an African Blackwood board. Stuff is dense and hard, but full of gummy bear juice.

What grit are you using?

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sweat the small stuff.

That's not the best Mike
I've just thicknessed an ABW FB on my 10-20 so I know what you mean.
Looks like 100 grit on the drum at a guess??
I'd be trying the blue stuff (zirconium oxide?) 60 or even 40 grit to start is I didn't have a safe-T planer first to save abrasive.
It can give a very reasonable finish, then 80 grit blue stuff on the drum, followed by a scraper plane.
Or there's always this -
https://www.youtube.com/watch?v=doJkt4Z62-0

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Dang! It eats normal plane blades too. I've been meaning to get an O1 or PMV-11 blade for it.

OK, that's not a fair picture. What happened was I sanded coco & ABW starting with 36 grit. No problem. Then 80 grit. Not too much trouble. Then a finish pass or two at 220. The coco did find. Not so much for the ABW. It actually STOPPED moving through the sander!!!!! On pass ONE!! LOL! I yanked out pretty darn fast.

I've been ripping through paper with bocote B&S. I didn't go below 80 though. I'll try that next time.


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Is that across the entire belt width?

How's the set up on your sander?

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

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My sander might need a tune up. I've noticed it. I just hate going there. Never ever saw a board stop mid way before. ABW gummy juice is seriously bad news.

And seriously, I should have known better.

Btw, if you've never tried thicknessing with 36 grit, u should. Risk is, deep scoring. Trick is, knowing when to stop and switch over to 80 grit. If it's a dry wood, you can switch to 180 or better on final pass. When using 36 grit, u need ear protection. Sounds like a planer. I have a huge roll of klingspor blue 36. Still on first strip after 20 B&S. And tops? Yeah, I went there. With tops, I switch at 4-5 hundredths out. With hard wood, 2-3 hundredths.

I never go above 120 grit when thickness sanding - no point really.
It's going to be handled a lot before it's built, and (probably) get the odd ding/scrape.
Level sand (and grain raise) for prep at 150/180/240 for WB finish or epoxy.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I never go beyond 60 or 80 on the thickness sander anymore... all the old 120+ grit rolls look like yours.

If it's clogging, you're feeding too slow, taking too much off, or both. For some woods as you have discovered you have to barely touch it so it takes forever to thickness. You have to remember that these drum sanders aren't really for thicknessing, they're for finish sanding.

FWIW, I retro-fitted my planer with a Byrd helical cutterhead with carbide inserts which takes a shearing cut. I can lower the head all the way down to 1/8" thickness and handle boards like this with virtually no tearout. Truly a miracle invention.

Fwiw, I just heard a choir of angels.....lol

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Pat

I leave 80 grit on my sander and just use a ROS on all pieces coming out of the drum sander.....

Lots of vacuum to the sander and really light passes (which I'm sure you know Mike) seems to help maintain life expectancy of my belts.....mind you not much you can do when sanding oily woods....

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Abranet

On a Drum Sander?

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I knew better. I only wanted one pass, maybe two. Very light passes. I guess my point is that if coco is bad (and it is) ABW is an order of magnitude worse. I did fine at 36 and 80 with the ABW. 36 is amazing. Never clogs. But it scores. So you have to stop before you get to desired thickness and use 80 to finish up. The whole 220 experiment is behind me. I'll probably get a roll of 120. For me, 80 and higher is not for thicknessing. It's for cleaning up score marks.

(80 is fine for thicknessing spruce, but I can and do use 36, but I stop sooner than with hardwoods)

Reminder: if you foul up 80 and want to save it, Easy Off is a great product for this. Turns the wood oils into soap, spray off with hose and let fully dry.

Thanks for that tip!

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I get probably 3-4 uses out of 80 grit strips that get fouled by wood oils (after using Easy Off). Sodium hydroxide clears the oil gum. But it's not easy on the binder. It's still better than tossing after a single use. You really need to let the strip fully dry before reuse.

For those who care, sodium hydroxide reacts with the wood oil in a process called saponification. Soap making. Sodium hydroxide, and more importantly, potassium hydroxide (lye) reside in wood. When wood is burned, the chemical is concentrated in the ashes. When the ashes are leached with water, the basic solution is obtained. It's odd to me that that wood itself contains the chemical agent that will reduce its essential oils to soap. Which, when given a good rain, the oils will disappear in a stream of bubbles.