Disc sanding on the lathe

[Eric Friedman]

I started to do some segmented bowls to empty out the flat scrap bin. To get the rings flat, I made a large MDF disc that goes on my face plate, attached some hook (and loop) to it. I then put some 4” klingspor paper on it.

Questions.

The paper eventually catches at the seams between strips during sanding and lifts. I’ve ordered some actual disc paper but I wonder if there are any tricks for making the adjacent strips of paper work?

Are there any jig ideas for bringing the ring to the sanding disc other than just holding it there with my hands? Through carelessness I let one slip and broke apart the segments. That lesson has been learned! I sort of imagine something where I can attach the disk to the tail stock and gently move it to contact the disc.

I see little tables that ride the lathe bed but that wouldn’t work for something as tall and narrow as a ring.

 

[Webb Willmott]

I found the best way to flatten a big ring is using my drum sander. Since it’s open on one end, I put half in and hand spin it like you would cut a circle on a bandsaw.

On a large disc, I use 3M spray adhesive and stick the regular sandpaper to the disc. I use a small C clamp on one side so I have a handle and free hand the rest of the ring.

The drum sanding method is far superior.

 

[Eric Friedman]

I found the best way to flatten a big ring is using my drum sander. Since it’s open on one end, I put half in and hand spin it like you would cut a circle on a bandsaw.

On a large disc, I use 3M spray adhesive and stick the regular sandpaper to the disc. I use a small C clamp on one side so I have a handle and free hand the rest of the ring.

The drum sanding method is far superior.

Yes a drum sander would be great, but I have no room. I wonder why no one makes one that can rotate up for storage against a wall.

I guess your advice is that spray adhesive (or sticky backed sandpaper) would not have the lifting problem of hook and loop, which isn't that secure. yes?

Regarding the c-clamp -- so the idea there is that you put a c-clamp on the "back" end (away from the disc) of the ring, sort of like the handle on a jointer push block? That seems sensible, though it would be cool to have something super quick to attach when flipping sides and that kept the fingers entirely free of the disc. It's low risk, I know, but having had a hand injury in the shop earlier this year, I'm keen on staying safe!

 

[Craig Duncan]

I just made a 11 inch plywood disc mounted to a face plate.
Ordered some of these but haven't tried them yet.

https://www.amazon.com/gp/product/B0CQP485G9/ref=ox_sc_act_title_3?smid=A115P6HQPJ9YX5&th=1

 

[John K Jordan]

I started to do some segmented bowls to empty out the flat scrap bin. To get the rings flat, I made a large MDF disc that goes on my face plate, attached some hook (and loop) to it. I then put some 4” klingspor paper on it.

Questions.

The paper eventually catches at the seams between strips during sanding and lifts. I’ve ordered some actual disc paper but I wonder if there are any tricks for making the adjacent strips of paper work?

Are there any jig ideas for bringing the ring to the sanding disc other than just holding it there with my hands? Through carelessness I let one slip and broke apart the segments. That lesson has been learned! I sort of imagine something where I can attach the disk to the tail stock and gently move it to contact the disc.

I see little tables that ride the lathe bed but that wouldn’t work for something as tall and narrow as a ring.

Without more info, some questions and perhaps ideas based on guesses...

What diameter are your rings?
What grit are you using?

What is the swing on your lathe? (i.e. can it swing a sandpaper disk large enough for the an entire ring?
I have a standalone belt disk sander and use 10" adhesive-backed sanding disks. However, a quick search of Amazon showed larger disks - I saw some 24" in diameter in various grits, for example this in 100 grit:

Amazon.com

Do you use any support or are you holding by hand?
I see Best Wood Tools offers a 4x12" steel table that attaches to the lathe banjo. If that would help, you might call for info. (Their website is sometimes not too useful)

If holding by hand and that's difficult to control, I'm wondering if it would be easier to make some sort of jam or Cole-jaws type of adapter to hold the piece from either inside or outside to keep it straight. This could be mounted on a live center in the tailstock if the rings were smaller diameter than the sanding disk.
But if the rings could be mounted and spun on the lathe, could they be flattened with a scraper?

I too use a drum sander (Performax 22/44) but my place would be a long walk from where you live! Are you in a woodturning club or know anyone in a woodworking club. Many have equipment and are willing to share.

Also, a friend took a glued-up table top to a local cabinet shop and they ran it through their big sander - don't know if they charged him anything.

Also, I have a roll of coarse grit sandpaper, maybe 18-24" wide (can't remember). I may have gotten it from a bin at Klingspor, can't remember that either! I've occasionally torn off a piece and taped it to my workbench and used it to flatten things - pushing across the paper by hand. Worked well but not real fast.

Also, for glueups (not for segmented but solid wood for Beads of Courage boxes and such), I've had good success by holding a big sanding block against the face. I glued some 2" wide coarse sandpaper to a fairly long 2x2 (using spray adhesive) and hold it against a surface while turning the wood at a low speed.
The pieces I usually use are like these, about to be glued together

Of course, these already have a way to attach them to the lathe! But if you used something like cole jaws or perhaps double-sided woodturners tape to attach a ring to an MDF disk in the lathe, a big sanding block might work. With coarse grit it's surprisingly fast to flatten a layer.

JKJ

 

[Gerald Lawrence]

I made a disc from MDF and added a faceplate to mount to lathe. Later redid that by gluing a sacrifical block in place of the faceplate and turned a tenon for mounting in chuck. I ordered pressure sensitive sand paper discs to mount on the sanding disc. It worked very well. Oh one thing you will need to do is face off the disc before mounting paper to make sure it is in one plane. You could probably use sheet sandpaper and spray adhesive if you wanted a disc 8 inches or less.

 

[Tim Hunter]

I either run them through my drum sander, or through my planer, or flatten them with a hand plane. There are many effective methods.

I also have an 18” disc-sanding setup for my big lathe, but have not used it to flatten segments:

Post in thread 'What’s on your lathe?'

Apr 7, 2023

Finish my sanding disc setup.




Now back to my elliptical bowl…

Tim

• Tim Hunter

• 

Tim

 

[Mike Novak]

The way I do it is terribly slow, but easy and accurate, and doesn’t require any new machinery.

1) put ring into Cole jaws on lathe. Hold sandpaper board against ring to flatten one side. My gluing can be messy, so sometimes flatten with scraper first. I just use a flat board with sandpaper wrapped around it. Maybe 4” wide, and long enough to cover both rims of the ring.

2) move Cole jaws from headstock to tail stock using chuck adapter on live center.

3) mount bottom of form on headstock. Flatten with sandpaper board held in hand.

4) apply glue. Use tail stock as clamp to hold ring in place. Cole jaws keep it centered, and allow rotating as needed for alignment. Hold clamped until glue grabs. I can normally find other things to do in the shop while I wait.

5) repeat for each ring.

If I had a drum sander it would allow me to glue multiple rings at once, but then I might have problems with alignment. Plus there’s lots of other things I would spend $1,000 on before a drum sander.

 

[Terry Sphar]

I started to do some segmented bowls to empty out the flat scrap bin. To get the rings flat, I made a large MDF disc that goes on my face plate, attached some hook (and loop) to it. I then put some 4” klingspor paper on it.

Questions.

The paper eventually catches at the seams between strips during sanding and lifts. I’ve ordered some actual disc paper but I wonder if there are any tricks for making the adjacent strips of paper work?

Are there any jig ideas for bringing the ring to the sanding disc other than just holding it there with my hands? Through carelessness I let one slip and broke apart the segments. That lesson has been learned! I sort of imagine something where I can attach the disk to the tail stock and gently move it to contact the disc.

I see little tables that ride the lathe bed but that wouldn’t work for something as tall and narrow as a ring.

I use my drum sander to flatten my segmented rings. You can make the pieces slightly thicker to account for any variations in the ring.