polishing epoxy

[HowardH]

I've just stuck my toe in the world of epoxy finishes and it's a lot of fun.  I want to use my RO150 to be able to get a glass shine by polishing through a 12,000 grit.  The Festool offerings only go through 5000. I saw this on Amazon
Amazon polishing pads and was wondering if you guys think these would work or are there better products out there that can be used with this sander.

 

[AlexThePalex]

The Festool offerings only go through 5000.

That is because after 5000 you're supposed to switch over to polishing compounds with a soft polishing pad. A sanding pad with sandpaper is too rough beyond 5000 and might mar your workpiece instead of improving it.

Festool offers a variety of pads of and compounds from 5000 up to 11000 grit (I believe). I have few pads and compounds myself for the Rotex 150 but I have not used them a lot.

Below the Festool system is explained by Phil Beckley from Festool UK.

Mind you though, the Festool pads and coumpounds are very expensive. Your local car accessories store will probably have a good selection of polishing materials for 1/10th of the Festool price.

 

[nclemmons]

The FT pads with the compounds are excellent.  I’ve used them to repair damaged finishes as well as new ones.  11,000 is a really shiny finish.  Very easy to use.

Don’t mix the pads with the different polishes.  That’s why they are color coded!

 

[HowardH]

The FT pads with the compounds are excellent.  I’ve used them to repair damaged finishes as well as new ones.  11,000 is a really shiny finish.  Very easy to use.

Don’t mix the pads with the different polishes.  That’s why they are color coded!

I've used those pads on my car before. I don't see where the grits are correlated with a color. Would they work on a mixed surface of wood and epoxy?  I'm making inlay but plan on using epoxy instead of a contrasting wood. 

 

[AlexThePalex]

I don't see where the grits are correlated with a color. Would they work on a mixed surface of wood and epoxy? 

They will work on any surface including wood and epoxy.

As for the colour coding, watch the videos.

 

[HowardH]

I did.  He labeled them by a generic system of fine, medium/fine, etc.  I was wondering if there was a corresponding grit, i.e. 8000 or 10,000.  Would they work better if I had a sander with a 3mm stroke instead of 5mm?

 

[nclemmons]

I used with the Rotex at low speeds.

Here’s the compounds and pads - they are color coded.

https://www.festoolusa.com/power-tools/polishing#SHINEX

 

[AlexThePalex]

I did.  He labeled them by a generic system of fine, medium/fine, etc.  I was wondering if there was a corresponding grit, i.e. 8000 or 10,000.  Would they work better if I had a sander with a 3mm stroke instead of 5mm?

The compounds have a grit rating, 5000, 8000, 11000 and so. Just google around, have a look at the Festool website. The colour coding is to match the proper grit compound to the proper pad and to avoid cross contamination.

Random orbit sanders do not work well for polishing so better forget about that. Polishing needs rotation and not vibration. Only the Rotex sanders from Festool work OK for polishing in their aggressive mode, because that rotates, but in general a dedicated polisher is what you need. A dedicated $20 polisher from Home Depot will work better than a $400 random orbit sander from Festool.

Edit: You have the Rotex, that one is good. Use the aggressive mode with forced rotation for polishing.

 

[Cheese]

Like Alex mentioned, I sanded West System epoxy to 5000 grit and then introduced a foam pad with a liquid polishing compound. It wasn’t Festool branded but it was approximately a 10,000 grit compound.

 

[Vondawg]

Agree with Alex and Cheese, this practice is the way to go

 

[HowardH]

Excellent advice from all! I did a little test case with the epoxy three days ago and it’s still tacky to the touch. I think I must’ve had the proportion off and may be a little too much resin versus the Hardner. Is that would typically would happen?

 

[Vondawg]

Give it more time hopefully your mix wasn’t off...soft epoxy will not buff out to high sheen.

 

[Crazyraceguy]

Give it more time. In general, if you were a little lite on the hardener, it will still cure. It just takes longer.
Vondawg is absolutely right. If it doesn't harden, it will never take polishing.

 

[nclemmons]

Howard - see if your epoxy ratios were by weight or volume.  That could have been the issue.

I've seen them both ways and they are not interchangeable!

 

[HowardH]

The brand I'm using is by volume.  MAS table top.

 

[dave10990]

The brand I'm using is by volume.  MAS table top.

  I am doing some resin projects, and have done some deep pours using Wisebond.  I have used MAS epoxy for a couple of kayaks I have built. and West for a real long time.  MAS is a really nice epoxy, and doesn't develop Amine blush like most others.  Accuracy is important in mixing the epoxy.  I have had to remove epoxy that didn't cure, and I know it was my error.  The table top epoxy may be a slow cure due to the fact it is used thicker than construction epoxy.  My deep pours take 24 hours to solidify, and several more days to harden.  I have waited more than a week to sand my projects, waiting longer may be what you need to do.  I have found though, that epoxy that is mixed with the wrong amouts of resin and hardener, just won't cure.  I have tried heat lamps, waiting, talking nicely to it, but still had to remove it.  Mixing small amounts are more critical to be accurate than a large pour.  You increase your margin of error as the volume increases.

 

[HowardH]

Next question about this subject.  I ordered the Festool Blue and White polishing compounds along with the corresponding sponges.  Will the compound discolor the bare maple as I polish the epoxy inside it? 

 

[Dust Devil]

If you’re using MAS Table Top for any pours over 1/4” you are using the wrong stuff and are going to encounter problems. Unless you have abraded the surface you shouldn’t need to polish the epoxy. Check out YouTube videos for detailed tutorials.

 

[Crazyraceguy]

I worked in the autobody industry for several years back in the mid 90s.  During that time I never saw the point of sanding any finer than 2000 grit, but that was wet and by hand. Either way, the compounds will polish away the scratches that it creates. They are also much faster at doing that than sanding anyway. I just don't see the point of sanding that fine, especially considering the cost of the consumables.
Most of what I polish today is either solid surface or the edges of acrylic sheets. I used to use automotive compound on solid surface tops, but I have switched over to a more plastic oriented compound called Novus.
I used an older version many years ago on the soft side windows of my Jeep convertible top. The new stuff comes in variable grit levels and works much better.

 

[Cheese]

Next question about this subject.  I ordered the Festool Blue and White polishing compounds along with the corresponding sponges.  Will the compound discolor the bare maple as I polish the epoxy inside it?

I did something similar with a piece of walnut. It had a large crack down the middle that I needed to fill with epoxy. This is the bottom where I placed the LED light strip, but you can see how long & how deep the crack is.

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Here the walnut cap is in place.

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A closeup of the epoxy & walnut without the LED's on.

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With the LED's on.

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To avoid the issues you're concerned about, I brought the entire surface to a 1500 or 2000 grit condition. And then the polishing of the epoxy was done with Boos Mystery Oil and after that an application of Boos Board Cream across the entire surface.

[attachimg=6]