Thread: PSA Sanding Disk Kit Supplies are in! If you ordered one then pls. read this post.

I received all the supplies for the PSA disk kits today. The punching is working well. I expect to have the kits ready to ship Thursday morning.

I am impressed with the PSA backing on this paper. The disks stick to the leather mandrel extremely well, yet can be removed and then re-used. The PSA does not loose its adhesion when you lift it off and restick it! Awesome. No wasted partially used disks.

I also have to appologize but I have to reneg on making two mandrels per kit for a the following reasons:

1. Keith De'Grau at HandAmerican did not have 1/4" leather in stock. He is planning to start carrying it later. Doubling up the 1/8" will make it too stiff.

2. When I ordered the mandrels there were less than 10 people. Now there are over 15 so I won't have enough mandrels if I try to make two for each person.

On the other hand these mandrels are stiffer than the leather from my belt which was my first mandrel. The whole reason behind wanting to try thicker leather was to make it stiffer and this leather already does this.

Those of you that ordered a kit can you please send me an e-mail or PM me with your e-mail address and shank size preference 3/32" or 1/8". If you have a Dremel then you can use either one because the dremel has an adjustible chuck. So pls. let me know if you are ok with either size. Some people might be more constrained and I would like everyone to get their kits without having to wait. I will make as many 1/8" as I can (I only have 12 mandrels of 1/8" shank, thought that this was overkill when I ordered them ) the rest will be 3/32". There is no difference except if you have a quick change handpiece for your flexshaft then you can only use the size of that handpiece which is usually 3/32" but can also be 1/8". If I run out of 1/8" shank mandrels I will have to order more.

I will PM you if you miss this post but if you send it to me first then it will save me a lot of time. I will be using most of it for next while to make the kits .

3/32 for me

Vlad - many people use the "reply to post" email tracking and will not see your new post. I found it by accident.

PM sent - I'm using a dremel, but I'll have to check the flex-shaft diameter.

Thanks

Originally Posted by synaptech

Vlad - many people use the "reply to post" email tracking and will not see your new post. I found it by accident.

PM sent - I'm using a dremel, but I'll have to check the flex-shaft diameter.

Thanks

Vlad

Can you add me to your standby list?

Thanks
John

John, I'll add you to the list. If all else fails I will send you my kit. I am so sick of punching these disks that I think I'll go back to hand sanding .

The tests went like butter but real life never is. I discovered that the sandpaper comes with two different PSA backings. One is a joy to punch, the other is its evil twin. Thicker and much harder on the punch. Sometimes the same grit has mixed PSA types.

The good news is that the mandrels are done, the only thing left is to sand them to even out the surface and I also finished punching 1500 grit.

The bad news is that I started with 2500. So only 3 grits are done. I spent half a day trying to improve the speed of punching. Now I just sit and punch away. Don't want to waste any more time on improvements just want to have it over with .

I must say that there are a lot of disks .

I can make either size work.
Thanks

So only 3 grits are done. I spent half a day trying to improve the speed of punching...

So, now that you are almost done, how bout this:

One of those hole saw bits. Grind a taper from the outer wall to the inside diameter at the cutting edge. This eliminates all teeth and leaves a knife-like cutting edge. Polish it. Put it in a drill press and cut away. Don't know how long it would last on the rougher grits.

Thanks Bill. I did just that for my tests and it worked great. For real live run it works BUT this is a lot of abrasives to punch. Tends to wear the cutting edge a lot.

I even rigged up a foot pedal actuated pressure pad for my drill press to keep the sand paper down while being punched. When I am done, I will take pictures of the set-up and the cutting bits, new and how they look after the punching.

I am through one hole cutter (DeWalt). Tried making another one only to discover that it is slightly off center at the cutting end. Not my grinding, this is how it was out of the box. This tends to smear a hair thin cut-off of the sandpaper & PSA on the edge of the disks.

Took another one, this time did not grind just tested in the drill press. It too is off kilter but I can return it and get my money back. Will pickup a couple more and hopefully find one that is straight and return the rest.

The other issue is that these cutters only have the teeth and a touch below them hardened. The rest is quite soft and tends to grind down fast. I tried to harden it with propane torch and a water dip. Works better but not enough. The next one I will grind off only the tops of the teeth and leave the rest. Not only does it leave factory hardened steel it also makes for an ondulating cutting edge. I made a small punch that way and it punches sandpaper like hot knife through melted butter, fast and with little wear. Tried to put these ondulations on the big punch and they get worn down fast because this part of the punch is not factory hardened.

What I really need is a new 1 3/8" hole cutter that is straight, centered and made from HSS.

I'll get there. It will probably take me another day or two.

Good news update. I just punched 2 more grits in two hours. So in another 6 to 7 will be done with this.

So the kits will go out Friday morning. This will give me a chance to package everything, label the boxes, etc.

I just finished punching the 100 grit. I am done and so is the second punch.

The last two grits: 100 and 150, did not punch but burned through. The punch would get hot enough after a few seconds of maximum pressure and then burn through the stack of sandpaper.

It held up pretty good all the way through to 220 grit but wore down on the last two. The punch made from a hole saw (the long type 2", DeWalt 1 3/8") now looks like it is made from two half cylinders because the edge wore off past bottom of the two slits on the side.

The last two grits took 2 hours each, while previous ones took under an hour. I resorted to using both hands to push down the drill press. It was not only long but physically demanding.

I just have to sand the mandrels to true their surface. This won't take long at all so the packages are going out tomorrow morning.

I took a few pictures along the way just in case some of you got curious to see what the setup looked like. I will include a before and after pictures of the punch and a picture of what you will be getting too. I will post these tomorrow. Right now I have to take a long shower and wash away all that burned PSA, paper and wood smell from my body.

Thank you all who have signed on for this kit and I hope you will enjoy it. I look forward to enjoying mine, probably after all this punching effort fades from my memory .