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View Full Version : Compounds/Polishes with ROS?



Andrew Helman
09-14-2015, 5:35 PM
For those of you who use rubbing compounds and polishes with a random orbital sander, how are you doing that?

Are you using Surbuf, wool bonnets, Abralon, etc.

Are you using a variable speed ROS? For example, I spoke to 3M about their Perfect It compounds, polishes, and finishing material, and they suggest 1200-1400 rpm whereas my Dewalt sander is 12k rpm (not 120000--typo).

Would the Dewalt work, or is there a high risk of burn through due to the rpms?

Any other thoughts? Anyone do it by hand successfully? Giving that thought to avoid risks of power tools.

As always, thanks for your time in reading and responding. It is appreciated.

Andrew

Warren Lake
09-14-2015, 10:48 PM
Do what by hand successfully, you havent said what you want to do what you are trying to polish car, furniture or what? your dewalt sander doesnt do 120,000 RPM even the space shuttle doesnt do that. Polishing is a series of steps based on what you have to work with from the starting point. you usually determine what you need after you do some baseline testing with polishes and pads that you know and you determine what needs to be done. There are many different products and new ones coming out continously.

Andrew Helman
09-14-2015, 11:25 PM
Yes, typo. 12k. Sorry about that. The context is finishing (rubbing) varnish on furniture after it has cured after having removed nibs and gotten the surface as level as wanted prior to bringing the gloss back.

Warren Lake
09-15-2015, 5:27 AM
I dont know varnish I know furniture finishes and automotive but would think the process is the same just a softer finish which in itself can be more difficult. If you are doing this for the first time you would be best to find a manufacturer and start with them and if they know what they are doing will give you guidance on their products.

You still arent saying too much,. Your process is this many coats then blocked, then this many more coats then blocked? blocked with what grit or grits etc ? small stuff big stuff? if you were doing little things than hand might enter into it. You are doing big stuff then forget it. you are blocking to some grit that is important to the process after that if you using some of the 3m stuff up to 1500 ,3000 , 5000 whatever it all makes a difference. ILl use 3M paper I dont use their polishes. If what you are doing is prepared really well and to a really fine grit you might be able to use a Makita Random 6040 to get the results you need after that. I use two machines at times last car I did had to start with wool. Hard paint with scratches from the previous owner. I didnt block it even though had a fair bit of peel as so many do these days but I wanted to leave as much clear on it as possible as it gets used alot.

I have many polishes and different pads and if you are doing different things all the time its necessary to have some sort of range, the last furniture finish I did was for a speaker manufacturer and it was very hard to work. Got a perfect mirror then looked at it a month later and it had turned to crap. Finish was defective manufacturer changed something chemical wise. Sounds like you are going to work one finish only so that should be fairly straight forward to get on track. you can do more with the sandpaper end of it and less with the polish end and that is usually a good mind set. THat is dont start polishing on a 1500 grit blocking take your sanding steps up high then less time on polish.

Scott Holmes
09-16-2015, 11:59 AM
I use a surbuf pad on a cheap Ryobi buffer/polisher (car version) on low speed ~4-6K with a bit of water as a lube and Finesse it 2 or Mernenza #3 finishing cream. Very light pressure, moving steadily.

Dave Cullen
09-16-2015, 3:48 PM
Polishing machines are not random orbit, they're rotational. You need surface speed to get the job done. What kind of buff you use depends on the type of finish and the compound. Some people like the old fashioned wool bonnets, others prefer foam pads. What compound you use depends on how hard the finish is and how finely it's been sanded.

In my experience, soft finishes like varnish don't polish very well. They tend to burn. The harder the finish the higher the gloss it can be taken to.

Warren Lake
09-17-2015, 3:41 PM
Old style used rotary more modern most final finish with a random. I used a 9227 makita orbital and 6040 makita random in the forced rotation mode. Old school just used rotary. At some point some found that using the random cancelled out swirls and it set up a new generation of machines to come. There are number of them available with different levels of excursion far more than our random orbit sanders. Dave look up Rupes and you will see just one company making them.

Andrew Helman
09-17-2015, 4:00 PM
I appreciate everyone taking time to reply. I gave Homestead Finishing a buzz because I was going to purchase a few Surbuf pads. The folks at Homestead, however, suggested that it would not be best to use a compound-and-polish approach with the 12k ROS that I have. So I'm going to skip it because I don't want to buy a polisher right now.

I don't have much that I want to do--some minor nibs and a tiny bit of texture to even out. I'm going to give it a whirl with what the folks at 3M suggested--wet sanding P2500, P3000, P5000 followed by their finishing material (like a post-compound, post-polish further liquid rub) by hand. They thought that the compounds/polishes cut faster than their sandpaper and said that the compounds are designed for extremely hard automotive finishes so a slower approach of sanding would be best. Interestingly, they said that the Perfect It I is like a P1200 or finer and that the Perfect It II is somewhere around P2500--the implication is that if you're using paper finer than that you're backtracking if you use P3000 and then hit it with compound and polish.

Thought I'd post this in case it is helpful to someone else now or in the future.

Again, thanks for taking time to respond. The interplay between compounds/polishes and varnish is interesting.

Andrew Helman
09-30-2015, 9:45 AM
Just a short update. I let the varnish cure a while and then did a light wet sand with very fine paper (P2500, P3000, P5000, all 3M Trizact); went light on the paper because I didn't have much texture to eliminate and the last wiped on coat wasn't hot-coated.

I gave it a whirl with the 3M Perfect It, Step 1 (a compound for use before a polish). Did it by hand twice. I'll go over it with the 3M polish tonight, time permitting. But I thought I'd share a few pics of how it came out by hand. It's not perfect (and my finish is not 100% level), but I think it'll be good enough for me.

https://drive.google.com/file/d/0B3OewcC540fkY2U4UG9TRDNXM1U/view?usp=sharing

https://drive.google.com/file/d/0B3OewcC540fkUlpUWjdvaGlsSkE/view?usp=sharing

https://drive.google.com/file/d/0B3OewcC540fkSWZiUzVrUUNEMW8/view?usp=sharing