LadyBlair
off to a rocking start
Living the rock life
Member since October 2020
Posts: 6
|
Post by LadyBlair on Jul 6, 2023 9:08:53 GMT -5
How do I remove and reposition flat lap disks with PSA backing? Should I just trim them around the outer circular edge with a sharp blade? Recently received new resin polishing pads with PSA backing and stuck them to pads. Then PSA to a hard disk. They looked centered when stuck together but don't run on the flat lap centered. Vibration issues. Yeah, I'm new to flat lapping and haven't needed to stick PSA together yet, what a learning curve. Would a blow dryer work to loosen the PSA and then peal off the new resin pads from the padding? Or will I ruin the new resin pads?
|
|
khara
fully equipped rock polisher
Member since September 2022
Posts: 1,980
|
Post by khara on Jul 6, 2023 12:07:34 GMT -5
I am in a similar boat. I actually have an old but not yet used up polishing pad stuck with PSA that I’d like to remove and try a different polishing pad, but that sucker does not want to come off. This is a good thing that they are so difficult to remove given that we use them with water and they spin, fast, but ya, I don’t know how we are supposed to remove them. I gave up on mine. I’m just continuing to use the old one and haven’t had a chance yet to try my new pad. And then my next question is, when the polishing pad is actually worn out, what do we do? Just stick another pad to the top of the old one? Trying to remove the old one seems like it will completely destroy the cushion pad. I’m going to tag jasoninsd . Maybe he has a thought. I know he’s done a ton of cabbing and maybe by now has used up a polish pad and needed to replace it. While good to know how to remove PSA, I’m kind of thinking for your situation, I’d probably do as you already considered, and cut the pads flush with the edges of the backing plate. Sharp exacto knife? Unless you have a large area/side where the cushion pad is not fully on the backing plate, it seems this should true it up and remove your wobble? PS- Blow dryer actually seems like a good option to try anyway. I would try it and just keep an eye on the pad surface and material for any changes. I’m curious what kind of resin pads you got. |
|
QuailRiver
fully equipped rock polisher
Member since May 2008
Posts: 1,640
|
Post by QuailRiver on Jul 6, 2023 17:33:30 GMT -5
I don't use the PSA pads for lapidary but I did use the PSA sanding discs for a while when I was a furniture repairman many years ago. And switched to the hook & lock backing pads for the very reasons you're mentioning. The PSA ones could be a @#$%^$ to remove from the rubber backing. Most backing adhesives I've seen do soften with heat so a hair dryer can loosen the adhesive grip a little but still may require some scrapping off while warm.
For lapidary resin discs I always bought the pads without the factory applied PSA adhesive and instead used "Lapidary Disc Cement" made by Leech. Once applied to the backing of a resin disc the disc can be peeled off and reattached several times without reapplication as long as it is kept clean. But I don't think Leech is still in business anymore but I have heard that 3M "Feathering Disc Adhesive" is similar and works for lapidary discs.
|
|
|
|
Post by jasoninsd on Jul 6, 2023 20:39:01 GMT -5
LadyBlair , khara, QuailRiver definitely had some great points. I've had good luck using heat from my wife's hairdryer to get the PSA to release. (I've ONLY done that when she wasn't home...so basically I'm trying to tell you I was being safe about it! LOL) I got a bunch of 6" 3M cerium oxide pads off eBay which have PSA backing. I'm able to get those off without a lot of work. I've never had one come loose when I've been cabbing (they're on the end of the arbor on my machine).
|
|
khara
fully equipped rock polisher
Member since September 2022
Posts: 1,980
|
Post by khara on Jul 6, 2023 23:30:11 GMT -5
jasoninsd Did you put your 3M disks on the original end lap that came with the machine? Did you remove that original CO disk and re-use the rubber pad and spin on plate?
|
|
|
|
Post by jasoninsd on Jul 6, 2023 23:43:15 GMT -5
jasoninsd Did you put your 3M disks on the original end lap that came with the machine? Did you remove that original CO disk and re-use the rubber pad and spin on plate? I have two polishing end disks for the machine. I carefully took off the original (heat and patience) and replaced it with the new one. I didn't damage the foam backing, so that was still good. There's no difference between the two disks I have...both are cerium oxide pads. I just have two. |
|
LadyBlair
off to a rocking start
Living the rock life
Member since October 2020
Posts: 6
|
Post by LadyBlair on Jul 7, 2023 9:59:57 GMT -5
Update: I soaked the resin disks with PSA to PSA backed pad to hard acrylic disks in very-very hot tap water (not boiling) for 15-20 mins each. With my hands in the water and the disks submerged, I gently pealed apart the resin disk still attached to the padding layer from the black backer disk successfully. The resin layer and pad came off the hard black backer disk under the hot water bath with quite a bit of pulling force. They didn't come off straight but rather in a pealing fashion. Then I laid he resin disk with padding still attached upside down on a towel and paper towel under the resin. Resin side down, PSA pad sticky side up. Used a blow dryer on low to blow off the extra water on the sticky PSA and my hands. As the PSA dries out from the water, it was still sticky. Then I put the PSA paper back on the disks. Stacked the resin disks with the paper backing on with a hard disk in-between and layers of blue paper towel to dry flat with some pressure from the black disks (pic 2). Toppers were not re-attached. I suppose if one wanted to adhere the resin topper back to the hard bottom backer disk, they could, but I didn't. I decided to wait until the resin topper disks dried and try the disks first before pealing off the PSA paper. If they run flat, I may or may not stick them to the disks. Testing the disks this weekend.   |
|
|
|
Post by Starguy on Jul 7, 2023 12:43:22 GMT -5
Once the PSA was worn out, I’ve used plain old rubber cement to reattach charged Crystallite pads. It worked pretty good and the pads could be semi-easily detached several times. When attached, the surface of the pad felt a little uneven because the rubber cement was lumpy. It didn’t seem to hurt the polish.
|
|
khara
fully equipped rock polisher
Member since September 2022
Posts: 1,980
|
Post by khara on Jul 7, 2023 22:59:41 GMT -5
jasoninsd Did you put your 3M disks on the original end lap that came with the machine? Did you remove that original CO disk and re-use the rubber pad and spin on plate? I have two polishing end disks for the machine. I carefully took off the original (heat and patience) and replaced it with the new one. I didn't damage the foam backing, so that was still good. There's no difference between the two disks I have...both are cerium oxide pads. I just have two.Jason..... have you gotten to where you are cabbing with both hands?... Be honest... |
|
|
|
Post by jasoninsd on Jul 7, 2023 23:06:56 GMT -5
I have two polishing end disks for the machine. I carefully took off the original (heat and patience) and replaced it with the new one. I didn't damage the foam backing, so that was still good. There's no difference between the two disks I have...both are cerium oxide pads. I just have two.Jason..... have you gotten to where you are cabbing with both hands?... Be honest... Well yeah I use two hands...but if you're implying I have one in each hand...NO! LOL |
|
