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I resawed 2 sets of Zircote. When I try to thickness these I get build up on the drum sander and start burning the wood. I am using a Jet 16-32. 100grit. What am I doing wrong?

Thanks
Richard

Use a courser grit (60 maybe) to wrk it close to final thickness.

Yep - 100 grit is useless on hardwoods for thicknessing - it will clog up - can be used for a final cut if you want to smooth it out a bit. I'd go down to 60 at least for real thicknessing, and I think I recall others talking about going even lower on another post earlier.

Light cuts, fastest feed rate, and frequent cleaning of the belt. Working across the grain might help also.

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Gabriel Regalbuto
Carlsbad, California
Freedom 35!

80X will work also as a starting grit. Just take small bites. If you take too much in one pass, you'll load the paper and then it's hard to recover without burning.

Use coarser grit (60) and then move to finer grit (I use the ROS) to smooth off when close to final thickness.
If you have a very resinous 'stripe' in the wood, moving the stock to feed on the diagonal can help if possible; shifting from side to side on subsequent passes can help also.
Get that clogged paper off the machine right away, unless you can clean it 100% with the 'big eraser'. I hear that you can clean the 'paper' (if it is is the red cloth-backed stuff) with EasyOff oven cleaner and a bucket of water.

When you are muttering "@&*@&@^@" while changing the sandpaper, just think how long it would take to thickness that wood with a cabinet scraper!

Cheers
John

Easy off will work - even with cocobolo resins that look like bubble gum.

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Gabriel Regalbuto
Carlsbad, California
Freedom 35!

And a little trick I learned from my friend Ed.
Wipe the wood with mineral spirits before each pass through the sander.

Steve

Maybe it's just my unit, but I found slow feed rate and light cuts works best for me at least on African Blackwood which has given me grief in the past.

I start on (really hard) hardwoods with 36 grit, the to 80 for the final .020" or so.

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I didn't mean to say it, but I meant what I said.
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Ziricote is about the worst wood in this regard, in my experience. Worse than coco, even. I'm in the coarse paper, fast feed rate, sideways pass camp...

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Rian Gitar og Mandolin

For removing larger amounts of material especially on more resinous woods, I use a Wagner Safe-T-Plane. I have about 4 of them now (Swapmeets are your friend ) so don't need to stop and resharpen when working a set. They do need to be 'sharp' to work well. If you only have one unit you are unlikely to get a full set ready for the sander without needing to stop and re-grind. The actual grinding only takes a few minutes, but it requires that you disassemble your set up for thicknessing from the drill press, install the sharpening stone, grind the 3 cutters, and then reassemble your thicknessing rig back onto the drill press. This is only real down side to the tool IMO and having a few units read and on standby solves the problem nicely.

As for the 16 32 sander, another vote here for course paper with light, fast and alternating passes angled to the grain.

To clean gummed up paper, throw it in a bucket of water over night or longer and then hose it off. You can use any detergent in the water if you wish or none at all because plain water works well on it's own. If a stubborn streak won't hose off, use a course brush to lightly agitate and it will be gone. I have a pressure washer that works well but considering how well just a simple hose down will work I can rarely justify the time it takes setting it up and putting it away again.

Cheers

Kim

Good to know, if that's the case then I have thrown away lots of perfectly good sand paper

Richard

Another vote for 60 grit, fastest feed rate, very light cuts running same cut height for several passes, then barely increase the cut depth and repeat.

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"Try to be the person your dog thinks you are."

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I vote for the safety planer too. I rough thickness with it and then go to the sander. Glad for the heads up about ziricote, as that's one of my next in line.

Kim - Are you saying you can't do a single set without having to resharpen the safety planer? I work slow, but I have yet to sharpen mine. I've run at least 5-6 sets through it - no problem. At school, I think we'd get 20-30 sets through at once, but Robbie may have been sneaking off to resharpen it when I wasn't paying attention.

Mike

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Mike Lindstrom

Mike, I guess it depends on the wood at hand and how much you need to work off of it. They don't stay sharp for long on some of the desert woods like mulga, jam and gidgee or on anything with a lot of silica in the grain. My comment in this topic was made with memories of a set of bocote I bought in one of the OLF swaps a few years back. Bocote and Ziricote are the same family and this set was 'really' thick. I would have sawn off the waist with the bandsaw but needed to replace the blade which I did not have at hand. I took the set to the drill press and there is just no way I would have got it down ready for sanding on just one sharpen, to do the back plates and sides took at least two trips to the grinder but even EIR can dull them quite quickly, especially the wide grained plantation stuff because the fast growth must suck up the silica.

Anyhow the experience with bocote was when I decided to start stocking up on them when I seen them going for cheap. The other point is that I also find things go a lot smoother if I stop cutting before the cutters are real blunt and just change over once I feel the tool is not cutting to it's optimum. The blades only take a moment to touch up and because I do them all at once it is not such a chore. To ensure consistency when sharpening I use a close fitting drill bit in the hole of the cutter to rest across the jaws of a small vice. This sets the cutter height, then I line up the ground edge to the wheel and lock it in. Then it is just a matter of turning on the drill press and feeding the cutter to to disk for a touch and she's done.

Cheers

Kim

You can't compare a safety planer to a thickness sander . I agree that you cannot use that fine of a grit. I don't own anything finer than 80. When you are sanding feel the surface of the wood . If it feels hot you need a faster feed rate and coarser paper. Also all that mineral spirits will do is clean off the dust . It is also flammable .
If you have much to take off use the 60 grit , and take it down to about .005 of your final size, that you can sand off in the finish process. As you sand look at your work , and if you see shiny spots , your paper may be glazing over and loading up. Use a cleaning stick , they are available at Grizzly .
http://grizzly.com/products/Pro-Stik-Be ... arge/G2520
A clean belt is a good working belt

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Who was doing that John???

John,

The mineral spirits lubricates the wood and keeps the resin from building up and clogging the paper. If we are to discount every products usefullness because of it's flamability, we'd have nothing left to build guitars with.

Steve

My #5 and #4 plane does not catch on fire -

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Gum rubber stick often to keep clean. A piece of acrylic used the same way will knock off the most of the build up most of the time if caught right away.
Other wise the the a fore mentioned advise applies. Fast feed, 60 grit, diagonal fee, cleaning belts in off the machine, etc.
Link

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Cut to size.....Beat to fit.....Paint to match.