revisit my conical disk and sandpaper issues

reible · Post by **reible** » Tue May 19, 2009 5:12 pm

Hi,

Sometime back we were having a discussion about this general subject but I don't recall where that was.... so I'm starting this thread. If someone recalls the thread please post the information here.

Think of this as a FYI more then anything else.

One issue I have had was with the swapping of sandpaper on my conical disk. As you know you should be able to take a grit off and put another girt on and save the original to reuse. I however have and problems doing that.

I've owned my disk for a long while, very shortly after they came out... I normally use the 80 grit and a couple of years back decided to try the grit swapping. Putting the new disk on has never been a problem but when I replaced the old grit back on it decided to fold back and among other things marred my almost new 520 table.

After our discussions and having a good number of people say they were having no problems swapping I went ahead and tried it again last fall. I didn't have a lot of sanding to do but it seemed to be working fine. It has sat since then until yesterday when I was getting ready for a project that could use the conical disk.

When I pulled it down this is what it looked like:
[ATTACH]4578[/ATTACH]

When I lifted the paper I could see the glue was on the paper and the disk had no sticky spots. I removed the paper and found that all told only about 3 places on the disk each about the size of a nickle were sticking to the metal.
[ATTACH]4579[/ATTACH]

I re-cleaned the disk and added some 3M adhesive. Have to see how this works this time.
[ATTACH]4580[/ATTACH]

Ed

JPG · Post by **JPG** » Tue May 19, 2009 6:24 pm

http://www.shopsmith.net/forums/showthr ... L+DISKS%27

http://www.shopsmith.net/forums/showthr ... AL+DISK%27

greitz · Post by **greitz** » Tue May 19, 2009 6:32 pm

Hi, Ed- when you put the paper on, how much pressure do you use? I assume they call it "PSA" for a reason, so I put the disc face down on a scrap board and push on it pretty hard while rolling it around. When I take the paper off, I have glue spots on both the paper and the disk, most of them being much smaller than a dime.

If it makes a difference, the disks I have are all about 3 years old. Maybe SS has switched suppliers?

Gary

robinson46176 · Post by **robinson46176** » Tue May 19, 2009 10:34 pm

I am reverting back to my old shoe cobbler days for this solution. Even with modern contact cements a good shoe man knows the best way to assure a good bond is to clamp the parts together in a press with a constant even pressure. Consider making a jig with a mirror image depression to match the conical sanding disk. Apply a layer of a firm foam (crepe shoe soling would be about ideal) to the depression. Then not only could you press the sandpaper on the disk when installing it, but you could store the conical disk in the press when not in use and it should always stay stuck together.
You could build a simple press like this one:
http://www.bookbinding.net/amateurs/images/fig4.jpghttp://www.bookbinding.net/amateurs/images/fig4.jpg
but out of wood with the depression made into the base. You wouldn't need or want a huge amount of pressure.
When trying to reapply a used paper to the disk you could place it in the press and heat the disk with a blow dryer or heat gun then let it sit in the press until it cools.

JPG · Post by **JPG** » Tue May 19, 2009 10:38 pm

robinson46176 wrote:I am reverting back to my old shoe cobbler days for this solution. Even with modern contact cements a good shoe man knows the best way to assure a good bond is to clamp the parts together in a press with a constant even pressure. Consider making a jig with a mirror image depression to match the conical sanding disk. Apply a layer of a firm foam (crepe shoe soling would be about ideal) to the depression. Then not only could you press the sandpaper on the disk when installing it, but you could store the conical disk in the press when not in use and it should always stay stuck together.
You could build a simple press like this one:
http://www.bookbinding.net/amateurs/images/fig4.jpghttp://www.bookbinding.net/amateurs/images/fig4.jpg
but out of wood with the depression made into the base. You wouldn't need or want a huge amount of pressure.
When trying to reapply a used paper to the disk you could place it in the press and heat the disk with a blow dryer or heat gun then let it sit in the press until it cools.

Bad link Farmer!

robinson46176 · Post by **robinson46176** » Tue May 19, 2009 10:51 pm

Trying again:
-
I am reverting back to my old shoe cobbler days for this solution. Even with modern contact cements a good shoe man knows the best way to assure a good bond is to clamp the parts together in a press with a constant even pressure. Consider making a jig with a mirror image depression to match the conical sanding disk. Apply a layer of a firm foam (crepe shoe soling would be about ideal) to the depression. Then not only could you press the sandpaper on the disk when installing it, but you could store the conical disk in the press when not in use and it should always stay stuck together.
You could build a simple press like this one:

but out of wood with the depression made into the base. You wouldn't need or want a huge amount of pressure.
When trying to reapply a used paper to the disk you could place it in the press and heat the disk with a blow dryer or heat gun then let it sit in the press until it cools.

JPG · Post by **JPG** » Tue May 19, 2009 10:56 pm

robinson46176 wrote:Trying again:
-
I am reverting back to my old shoe cobbler days for this solution. Even with modern contact cements a good shoe man knows the best way to assure a good bond is to clamp the parts together in a press with a constant even pressure. Consider making a jig with a mirror image depression to match the conical sanding disk. Apply a layer of a firm foam (crepe shoe soling would be about ideal) to the depression. Then not only could you press the sandpaper on the disk when installing it, but you could store the conical disk in the press when not in use and it should always stay stuck together.
You could build a simple press like this one:

but out of wood with the depression made into the base. You wouldn't need or want a huge amount of pressure.
When trying to reapply a used paper to the disk you could place it in the press and heat the disk with a blow dryer or heat gun then let it sit in the press until it cools.

MUCH BETTER!:D Sure it is NOT some torture device???:eek:

reible · Post by **reible** » Tue May 19, 2009 11:42 pm

JPG40504 wrote:https://forum.shopsmith.com/viewtopic.php?t=2671&highlight=%27CONICAL+DISKS%27

https://forum.shopsmith.com/viewtopic.php?t=2993&highlight=%27CONICAL+DISK%27

The top link is to the posting I was referring to, thanks for finding it.

As I mentioned I only see this happen when I REUSE the sandpaper. If it is new and I put it on it stays just fine and will stay until it is used up. I can then replace it with another new piece of sandpaper and have done this many times... NO PROBLEMS at all.

If I take a sandpaper off and put it on the backer paper then put it back on the disk I'm 2 for 2 with having problems. In this second case I even sanded with it last fall and it worked fine... but over wintering took its tole and the paper was quite loose when I went to use it. Had that been a fresh piece of sandpaper I can about say for sure it would have still been stuck down(this was the first time I have ever seen sandpaper do this over a winter and the first time I have had reused paper on the disk over winter.

Since I use the same basic process with new sandpaper as I do with the "reuse" sandpaper I would have expected them to act the same way, however that has not been the case for me.

If I recall correctly this paper is in the 3 or 4 year old range, however it could be 5 or 6 as I tend to stock up. This batch might take me through this season so later in the fall or next spring I have to order more... it will be interesting to see if my issues are related to this shipment or if I have a generic problem. Or maybe it is time for me to get a second conical disk in my budget for next year.

Ed

charlese · Post by **charlese** » Wed May 20, 2009 1:33 am

reible wrote: One issue I have had was with the swapping of sandpaper on my conical disk. As you know you should be able to take a grit off and put another girt on and save the original to reuse. I however have and problems doing that.
Ed

Sounds like your problem with the disk is caused by Northern Illinois climate and cold weather.

Solution! buy more disks or MOVE!

a1gutterman · Post by **a1gutterman** » Wed May 20, 2009 2:05 am

It is a larger outlay of cash, but for me the solution was to have a separate disk for each grit. That goes for the conical disk and the flat disk. The only time that removing a sand paper disk is required is to replace a worn one with a new one. A great time saver and no problems with re-using previously removed disks!