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A few weeks ago I poking around again in that Woodworking for Engineers site and I went deep enough to discover that the auther of the site, Matthias Wandel, is here in Ottawa. So I sent him a message inviting him to my place to see how guitars are made and encourage him to make clever guitar making jigs. He's an interesting fellow. Scary smart, "retired" from the high tech industry and now making a very good living off his web site. Anyway, he took an interest in my drum sander since he's had a lot of people asking him to build and put up plans for one. He asked if he could do an article on it which was fine by me. He took pictures and video and from those made up the article and plans which you can find here:

http://woodgears.ca/sander/thickness.html

Hopefully, the plans will be of use to someone.

Cheers,
Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

thank you for the plans

Nice, Pat.
Thanks for answering my P.M.
Alan

Pat,

Thanks for the link and the plans! I have to ask though - with so many dust producing machines in that area you have, as I understand it is not a great idea to have it near the gas water heater ? Isn't there a risk of fire with what you have surrounding the gas flame ? I see dust producing machines and cardboard.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

John,

I would be the first to agree that working next to a hot water heater and furnace is not the best situation. I do have ventillation to the outside as well as dust collection. As it happens, I am also currently pricing out the cost of a new workshop above my garage.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Yes - I was curious about this more than critical of it - as I plan to build a new shop in a new house as well. I noticed the space I have available to me also has the water heater and furnance. I may have to enclose my workshop to keep the dust to a mininum near the equipment. Only draw back is that I do not have ventilation to the outside.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

Hi Pat,
Thank you for the plan and video, I want to try and build my own soon.
A couple of questions:
Do you find it hard to have a steady and consistant manual feed of the wood and does that affect the thickness at various points on it?

How are the MDF disks fastened to the shaft so they don't slip, epoxy?

Thanks

Hi Rusty,

A steady feed is indeed important to get a finish without any indications of a ripple. So the closer I get to final thickness, the more I pay attention to pushing the wood through at an even pace. Even then I am sometimes left with just a shadow of a ripple but this is no big deal, I remove these during later sanding with an orbital sander.

In answer to your second question, I was wondering the same thing myself when I was starting to build the sander. It turns out that disks fit quite tight on the shaft, I really had to pound to get them on, and it didn't take me long to realize that once they were all on and glued to each other, they wouldn't be going anywhere. So nothing was required (other than friction) to keep the disks from moving on the shaft.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Rusty: Don't want to steal any of Pat's or Matthias's thunder but will give you my take on the sander. I also built a sander a few years back and the basic principals are very similar to Pat's. I used a 3/4" cold rolled steel shaft that I find strong enough to do the job and allows the use of 3/4" aluminum pulleys which are readily available. I used a 3/4" forstner bit to drill the holes in the MDF. The discs pushed on the shaft and were glued as assembled with titebond. To drive the discs I machined the outer face off a 3/4" pulley until it was flat,drilled 4 holes for wood screws and attached to the drum,tightened the set screws into indents drilled into the shaft. It's as solid as a rock. I think having MDF discs is no problem as the drum can so easily be trued without taking the machine apart. The sanding paper I use is about 3" wide and wound on in a spiral fashion and fasten on both ends with large hose clamps. Congrats to Pat and Matthias for making the plans available.
Tom

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A person who has never made a mistake has never made anything!!!

Thanks for posting this, and providing your plans! I'm going to build one this week.

Is there a good reason to use MDF for the drum, rather than high quality plywood, or even solid hard wood?

Also, where's a good place to get the velcro, and velcro sandpaper?

Thanks,

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Regards,
Phillip Patton

http://www.pattonblades.com

The bitterness of poor quality lingers long after the sweetness of low price has faded.

https://hoosierbladesmith.wordpress.com

Philip,
Woodmaster Tools has the Velcro sandpaper and the Velcro backer.

Thank you, sir! I shall order some straightaway.

The sanding drum on this design is wide enough to sand a joined guitar back. Does it actually work well for that? Is the drum rigid enough?

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Regards,
Phillip Patton

http://www.pattonblades.com

The bitterness of poor quality lingers long after the sweetness of low price has faded.

https://hoosierbladesmith.wordpress.com

Yes, I do my joined tops and backs on this drum sander. The only issue I have is that it needs to be re-trued periodically (I've done this three times in five years). I don't know why this should be so, but eventually, I can feel the wood I'm pushing through pulse against the turning drum rather than consistent resistance. Matthias suggested it might be due to changes in humidity. To re-true I take off the velcro and re-sand the drum against the table.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Cool. I've been having some of my wood sanded down by someone else, and they charge $50 per hour. I figure this sander will pay for itself just in the first 2 or 3 guitars.

I wonder if sealing the drum with shellac would help prevent movement? Would the velcro stick to shellac?

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Regards,
Phillip Patton

http://www.pattonblades.com

The bitterness of poor quality lingers long after the sweetness of low price has faded.

https://hoosierbladesmith.wordpress.com

The velcro is very sticky. I'm sure it would adhere to shellac.
Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Another excellent Monday article on the woodgears site, and that drum sander will assist quite a few people, I am sure.

Matthias Wandel is IMO a 21st century Leonardo da Vinci ...

Whats the best way to make those MDF discs?

I don't know what the best way is, but what I did was use template (actually the 5" pulley) to draw the circles on the MDF, then cut them out close to the line with the bandsaw, then sanded to the line with my belt sander. Then I used a compass to find the center, drilled a pilot hole, then used an awl through the pilot hole to mark the others. Then I used a 3/4" forstner bit to drill the shaft hole.

It got pretty tedious, and I ground off part of my left thumbnail at one point, but it took less than 2 hours, and looks pretty good:


http://www.pattonblades.com/4511-10.jpg

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Regards,
Phillip Patton

http://www.pattonblades.com

The bitterness of poor quality lingers long after the sweetness of low price has faded.

https://hoosierbladesmith.wordpress.com

The discs don't have to be exact as they clean up very nicely when you true the drum with the sanding block. I just laid mine out and bandsawed. Looks a bit rough when you glue up but cleans up quite easy. I did not leave gaps between discs and used titebond glue,disc locked at one end of shaft as explained in earlier post. Also I did not use velcro but rather just wraped the sandpaper on the bare drum.
Tom

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A person who has never made a mistake has never made anything!!!

Pat,

Thanks for sharing the information on your drum sander.

Max

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Max Bishop
Brighton, Michigan

Hmm..... looks very familiar!

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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.

Very cool Pat, congratulations. I really like the binding jig though, that looks so light weight and compact. It looks easy enough to figure out, but if you had some info on that, I may get to work on one of those shortly.

Not sure if it would be the best way, but an accurate and quick way to make circles with a band saw or horizontal belt sander is to spin the blank on a pivot. Start with a board, for this project maybe 4" wide, 18" long. Attach a stick to engage the crosscut slot on the saw so the board is close to the blade. Measure from the blade and mark on the board the location of the radius, screw the blank in there. Make a stop for the sled so the blade aligns with the center of the circle. Push the sled and blank into the blade until it rests on the stop, then spin. If one were to be fancy, the screw location would be on an adjustable track, as would be the cross cut bar, then one could go from the bandsaw to the horizontal belt sander with the same jig and make it spiffy.
Delta used to make a circle jig something like this, great simple tool, too bad they discontinued it.
Rob

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Rob,

Here is an earlier thread I started on my binding jig:

http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=19236

As you will see, I can't take original credit for the design. I believe that belongs to Dan Fobert and then Wes McMillan copied it and posted on this forum. It's like a two dimensional Williams jig so it is much simpler/cheaper to build and takes up less space. Yet since the principle upon which it works is the same so it works just as well!


Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Pat: Did you use that thickness sander to make that fine looking tennis racket guitar you're playing in your avatar?

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

Yep, I started with my old, wood Dunlop Maxply, put it through the thickness sander and out popped a titanium/graphite Head. That sander is a great tool.

The idea behind my avatar was to show a little about myself. My tennis club opens up for the season on April 26th and I've already got a ticket to the Jimmy Buffett concert happening in Toronto on July 16th. In July I become officially semi-retired from my regular job of keeping nuclear reactors safe for Canada. Life is good.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.