PTWFE Chapter 17 Disc Sanding

[JPG]

This weeks ptwfe chapter is on Disc Sanding. Click to get it.

STILL need volunteers for the remaining chapters!:)

[reible]

Just finished my reading, how about you??

When I started woodworking this was not a tool we had at home, didn't know anyone with something like this. H.S. shop nothing like this either. The strange thing was I didn't even think about using one much less owning one. The ad's for the shopsmith showed it and it was part of the list of tools but it was clearly not "pitched" to me the right way.

It wasn't until I was setting up my own shop that I discovered that I could buy a sanding disk with a flat side and a conical side that fit my table saw. The conical design caught my eye. Sure I had to have one and then it became a lot more interesting to me as a part of a good collection of tools. It wasn't until then that I even started to think about the fact that shopsmith understood that and had been promoting it since their beginnings. At that point I wanted a shopsmith even more then before.

I wonder how many of today's purchasers ever think about the true value of having such a tool in their shop??? I also wonder how many shopsmith users are missing out on using what they have... this is a really great sanding system and should be a tool you use.

Now, read the chapter, ask any questions that come to mind and make some saw dust.

Ed

[nuhobby]

I think the Mark V Disc Sander is an amazingly handy tool. I use it all the time.

In the sometimes-debated question on "should the Mark V always be started at slow speed?", the 12" steel sanding-disk mode gets my vote for starting "slow." There is a mighty flywheel effect from the disk's mass, and you don't want to start that at high speeds. I had one stupid mishap where I did this at full "Fast" speed, and the machine went unstable -- belt sheaves did not settle out for some time. And that overstressed the idler bearing.

Other than that, though, it seems OK to start at ~ Sawing speed with the fairly light 10" circular saw blades.

[JPG]

I think the Mark V Disc Sander is an amazingly handy tool. I use it all the time.

In the sometimes-debated question on "should the Mark V always be started at slow speed?", the 12" steel sanding-disk mode gets my vote for starting "slow." There is a mighty flywheel effect from the disk's mass, and you don't want to start that at high speeds. I had one stupid mishap where I did this at full "Fast" speed, and the machine went unstable -- belt sheaves did not settle out for some time. And that overstressed the idler bearing.

Other than that, though, it seems OK to start at ~ Sawing speed with the fairly light 10" circular saw blades.

The older aluminum 12" disc are not as heavy as the newer steel ones. Even though lighter, starting at too high a speed will either result in belt slippage or the scenario you just described.

This is one accessory where speed should be set prior to attaching it, or 'always start at slow speed regardless'(proper procedure anyway!!!!).

[nuhobby]

Man, I'm so happy!

The electric weedeater went bad the other day. One carbon motor-brush and its wire were fractured from each other. I didn't have the right replacement brush on hand. BUT -- I looked at an old router motor-brush I never threw away, and 2 of its 3 dimensions were correct. I used the Disc Sander to modify the 3rd dimension. Result: Weedeater is again good as new!

[e.friedl]

I'm in agreement the disc sander is a great accessory that I would have never bought on it's own. But after using my Shopsmith and the disc I wouldn't want to be without one. And the conical disc is someways is even better. I didn't have a joiner and at first I used the offset fence with the flat disc. That was alright but I didn't like re adjusting the fence. The conical eliminates the need to reset. Since then I have adapted an old non-Shopsmith joiner to work with my 10ER (yes I'm one of make do people) and even still for a small amount of work I still use the conical disc.
Ed Friedl

[tryinhard]

For my level of novice woodworking, the conical sander is perhaps the best accessory I have purchased. In the past, I have used the drum sander with the shaper fence to sand the edge of the boards. But the 150 grit on the conical disk seems to give a better edge by several magnitudes.

I think SS should rethink their Sanding package. The "disc sanding package" is two flat discs with a large number of AO pressure-sensitive sanding discs. I don't see how you get a "smooth, professional look" since the flat discs leave swirl marks. To give the best overall sanding capability, maybe the sanding package should consist of one flat disk with velcro, an assortment of velcro sandpapers, and a conical disc with sandpapers. The velcro flat discs give the versitility to use that disc for any and all the edge sanding needed right up to the final finish, which the conical disc does superbly.

I would also like to see every grit, including the new offerings, in the circular disc inventory available in velcro. Or maybe instead they could offer a plastic disc with the velcro permanently attached to the back, to which you could take any of the adhesive sandpapers and stick to the front, and then the whole assembly gets pressed onto the velcro-covered flat disc. The plastic disk could be used over and over when the sandpaper attached wears out. Think it would work?

[JPG]

For my level of novice woodworking, the conical sander is perhaps the best accessory I have purchased. In the past, I have used the drum sander with the shaper fence to sand the edge of the boards. But the 150 grit on the conical disk seems to give a better edge by several magnitudes.

I think SS should rethink their Sanding package. The "disc sanding package" is two flat discs with a large number of AO pressure-sensitive sanding discs. I don't see how you get a "smooth, professional look" since the flat discs leave swirl marks. To give the best overall sanding capability, maybe the sanding package should consist of one flat disk with velcro, an assortment of velcro sandpapers, and a conical disc with sandpapers. The velcro flat discs give the versitility to use that disc for any and all the edge sanding needed right up to the final finish, which the conical disc does superbly.

I would also like to see every grit, including the new offerings, in the circular disc inventory available in velcro. Or maybe instead they could offer a plastic disc with the velcro permanently attached to the back, to which you could take any of the adhesive sandpapers and stick to the front, and then the whole assembly gets pressed onto the velcro-covered flat disc. The plastic disk could be used over and over when the sandpaper attached wears out. Think it would work?

IMHO the velcro backed disks leave much to be desired. Sure they ARE handy and allow easy swapping of grit. The squishey surface you end up with does not lend itself to accuracy.

AS for the flat disk swirl marks, a fine grit leaves very small(shallow) swirl marks. A minimal amount of manual sanding will remove them. You CAN use the sanding disk by stopping it and swiping the workpiece across it while stationary.

Yes the conical disk IS preferred due the lack of swirl marks, but is totally unsuitable for velcro.

Any precision GRINDING requires a solid backing for the grit. A velcro backing is just too soft(variable).

The best scenario(although quite expensive) is to have multiple disks with different grits/paper type. I do not know of anyone who has 'too many' disks in use. My 'collection' takes too much room already.

[kalynzoo]

Yup, the sanding discs do make the SS a versatile platform. I like the changeability of the velco system. I have purchased some fine paper, 320 and 600 in velco sheets that I use on the disc. I have not had luck changing the glued paper, so I leave that at 120 for sharpening. The conical disc is grabbed first, before I go for the joiner. It is easier to set up, cleaner to use, and gives a more precise surface. (That' s because I have a cheap joiner ).
A second sanding disc is on my wish list. Just waiting for a sale, or free shipping. (anyone at SS listening )

[etc92guy]

I'm a beginner in the woodworking thing....probably will be for a while. Before the SS I used some sanding drums on my drill press. While I was happy with that result, the disc sander on the SS is head's above what the drill press setup could produce. While they will probably always have their place in my shop for "inbound" curves, if I need to shape something like a corner, I'll reach for the platter.

I bought one of those abrasive cleaning sticks to prolong the life of the sanding disk, but haven't used it yet. Can anyone comment on this process and extended disk life?

Also, I must confess I don't know what grit I'm currently using. I bought my discs used and one of them had a useable sandpaper disc attached. Got to remedy that one of these days. I also still have to read Ch. 17