Polishing plexiglass?

[promark747]

I would like to take some clear sheets of plexiglass/lexan/acrylic that have been beaten up/scratched, buff the scratches out and polish them to a clear (transparent) finish like they were when new.  Can I do this with my RO90, and if so, which pads and abrasives would work best?

Thanks

 

[Administrator_JSVN]

Yes, you can use the RO 90 for that, no problem. The only thing I'll comment about is the size of the pad may cause minor undulations. A larger pad size would help maintain flatness.

Without knowing the depth of the scratches, it's hard to say which grit to start at. I would recommend starting higher in grit than you think you need. You can always go down in grit if the process of scratch removal is taking too long. If the scratches are mostly superficial, you can probably start between 500 - 1000 grit. I'd recommend using Granat abrasives.

For polishing, you would probably want to pick up the polishing pad, 495625. Get the medium (orange) sponges, 493849. Use it with the 8000 grit polishing compound, 493816. When using the RO 90 for polishing, use Rotex mode.

I would suggest wiping down between grits with a damp cloth.

I had some video of the process at one point. I'll see if I can find it.

Shane

 

[promark747]

Thanks Shane.  The plexiglass isn't very big, so the RO90 size should be fine.  Glad to hear you recommend Granat, as that is what I have on hand.

 

[Administrator_JSVN]

Yes, Granat is a great abrasive for almost any application.

Here's a video that I did with Brian, our trainer, where he's demonstrating the same principles but on a lacquer finish. The steps and process are virtually the same.

 

[Sparktrician]

I've used a process very similar to the one Shane described for buffing out polycarbonate headlights using the RO 90 (and RO 125 for larger lenses).  I use Granat through 320, then Platin from 500 to 4000, then shift to a hard wool pad with 5000 polishing compound followed by a soft felt pad with 8000 polishing compound.  I should note, too, that I reduce the sander speed to ~50% when I shift to Platin and polishing compounds. 

 

[Dave Rudy]

Shane,

FANTASTIC video!  Very well done and informative.  I haven't done much polishing but many questions now answered.

What is the "release agent"?

Thanks.

Dave

 

[Administrator_JSVN]

What is the "release agent"?

Magical German water.  [wink]

 

[Dave Rudy]

Thought so.  I think I have a less expensive local supplier for it right here.  [eek]

 

[Administrator_JSVN]

I should have done something with this video footage a long time ago. I also found some old video footage of Sedge polishing auto headlamps. Again, virtually the same process as polishing the lacquer. This, however, is probably a better comparison to polishing Plexiglas (video available momentarily).

 

[Stephen B]

Yes, Granat is a great abrasive for almost any application.

Here's a video that I did with Brian, our trainer, where he's demonstrating the same principles but on a lacquer finish. The steps and process are virtually the same.

[size=11pt]
Thanks Shane, timely.

Just a thought re the MFT table top. It was wet by the end. If this process was used constantly on the MFT would there be permanent damage?

 

[Administrator_JSVN]

Just a thought re the MFT table top. It was wet by the end. If this process was used constantly on the MFT would there be permanent damage?

MDF is not well suited for being wet. It will degrade over time if it becomes wet repeatedly. I would recommend sealing it if you are going to use it for an application where it might get wet over and over.

Shane

 

[rst]

We do commercial plastics fabrication, mostly for the grocery refrigeration sector.  The trick with polishing plastics is slow speed and keep it wet.  Heat is the enemy here!!  There also are commercial liquid polishing compounds.. http://www.novuspolish.com.  These are used extensively by the commercial store fixture, refrigeration and airplane industry.

 

[dicktill]

Yes, Granat is a great abrasive for almost any application.

Here's a video that I did with Brian, our trainer, where he's demonstrating the same principles but on a lacquer finish. The steps and process are virtually the same.

Thanks Shane. He mentions using a "release agent" several times. What release agent, and what is its purpose?

Thank, Dick

 

[Administrator_JSVN]

Dick, see my response earlier in the thread about release agent.  [wink]

 

[dicktill]

Dick, see my response earlier in the thread about release agent.  [wink]

Yes, my education continues. Both on magical German waters and on reading all of the thread carefully.  [doh]

 

[jacko9]

I have used my RO 90 with Platin from 500 to 4000 grit to clear my headlights on my Acura MDX - works like a charm.

Jack

 

[Limey556]

While we are on the subject of polishing can anyone give me tips on re-surfacing or polishing  counter tops marble / granite ?
Would appreciate any tips on grits and paper type etc.

Thanks
Terry

 

[Administrator_JSVN]

Terry, I know when to admit the limitations of my knowledge and this is the time. If one of our members can't give you advice with marble, let me know and I'll put Steve Bace in touch with you. He's our guy with that type of expertise.

 

[Stephen B]

While we are on the subject of polishing can anyone give me tips on re-surfacing or polishing  counter tops marble / granite ?
Would appreciate any tips on grits and paper type etc.

Thanks
Terry

+1 please

 

[Administrator_JSVN]

Ok, I'll hit up Steve and get back to you guys. I'm guessing you might need a diamond abrasive for scratches and the polishing procedure is similar. And water as you sand.