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View Full Version : Disk sander - part 1



chrisb691
19th May 2007, 07:51 PM
I am preparing the jigs I will need to have a go at segmented turning, and have made up a disk sander to sand the segments. This was based on the design that Skew put up, but with the addition of good dust extraction, and is fitted to my Jet mini lathe.

The pics are all after the fact, so there there isn't a step by step like Skew's. But there should be enough to give the general idea. The dust extraction works perfectly, with zero dust escaping (as far as I can tell).

pic1. Made up the box, and a strip of ply that is a snug fit into the gap in the lathe bed. Sat the box on the lathe with it's front face aligned to the sander disk, then slid the ply strip up from the bottom, using some spots of ca to hold it in place. The assembly was then removed, and the locator was screwed on. At the top of the front face, is a slot for the vacuum that sucks dirctly from the sanding disk. The vacuum hose attachment, is a modified vacuum cleaner tool, which is screwed onto the side of the box. The cut-out through the side of the box, is about 6mm smaller (L x W) than the vacuum tool.

pic2. Set up on the lathe, and clamped down. Clearance to the sanding disk is about 1 mm. 2nd vacuum slot is on the top face, near to the sanding disk.

pic3. The clamp down arrangement is simply a threaded rod inserted through the bottom, and locked in place by nuts. Then I have a U shaped clamp, that clamps against the bottom of the lathe bed via a nylon tri-nut (Bunnings).

pic4. The source of the vacuum is, of course, a vacuum cleaner, which I have hanging above the lathe out of the way This is one of the 'cyclonic' 1800 wt units, which I bought new off ebay for a good price (I think). It's got a variable speed on it, and I've found that it only needs to run at lowest speed to do the job. At this setting it's quite quiet, and wont upset the neighbours. The dust container is ridiculously small, and I dont see how you could vac a house with it. But it's certainly sufficient for what it's now doing. Later on, I am going to make a mini mini-cyclone, and then I'll hook up it up to the lathe.....but that's another project.

.......continued next post.

chrisb691
19th May 2007, 07:54 PM
pic5. Converted to a segment sanding jig, by attaching a fence, and a variable stop. This is from the book 'The art of segmented woodturning' by Malcolm Tibbets. The fence was squared to the face of the sanding disk, and then screwed down. Found that this arrangement restricted the use of the unit as a standard disk sander, as it gets in the way. So I have retrofitted it with 2 dowels. Now I can remove it for standard use of the sander, and refit it for segment sanding. The dowels get it back into a consistent position, every time.

pic6. Detail of the stop length adjustement. Simply a piece of turned pine, with a thread insert hammered into the end. Then a threaded tri-nut allows it to run up and down the routed slot, and locks it into the required position.

pic7. The sanding disk is made from 2 pieces of 12mm mdf glued and screwed, with a piece of 19mm pine glued on, which the face plate is screwed to. I added the pine as I found that I was getting some flex, when I pushed the segments into the sander. It also improves the screw mounting of the face plate. The front face, has self adhesive velcro backing stuck on (carba-tek), and is the same size a the velcro backed sanding disks (200mm).

pic8. I'm going to make a longworth chuck for the lathe, and I don;t want to keep buying face plates. So I wanted to be able to remove the face plate, but be able to get it back into the exact position again. So I have added a locating stud to the back of the sanding disk. This was turned so that it was a tight fit into the face plate, and then screwed/glued into position on the back of the sanding disk. Everything was then assembled, and trued up in the lathe. I can now remove/reinstall the face plate, and everthing still spins true. Had it off/on 3 time, and it works beautifully.

This is a really wothwhile addition to the lathe, and is really easy to make up. Many thanks to Skew, who introduced me to the idea.

watson
19th May 2007, 08:20 PM
Looks good Chris..I reckon we both owe Skew one, as I stole his idea as well

Skew ChiDAMN!!
19th May 2007, 08:35 PM
Good one, Chris! I like the mod's you've made, I think I may have to return the favour and pinch your ideas! :wink::D

DJ’s Timber
19th May 2007, 08:38 PM
That looks great Chris :2tsup: and dare I say it, better than Skews :o :U

Skew ChiDAMN!!
20th May 2007, 12:49 AM
That looks great Chris :2tsup: and dare I say it, better than Skews :o :U

OK, so maybe painting it GMC blue with GMC yellow detailing wasn't such a good idea... :p