Polishing Linear Polyurethane Imperfections

[isobelk]

check this site for some roll and tip info:

sltopcoat.htm

[isobelk]

another roll and tip primer:

http://www.boatbuildercentral.com/he...g_roll_tip.htm

[malbert73]

Originally Posted by garymcg

Ok, I think now would be a good time for you guys to give us amateurs the tips and tricks to a good roll and tip job. How about it? I think you're carrying around invaluable information that can't be obtained from a book.

Probably don't want advice from a fellow amateur, but here goes for my job which you could see in an earlier post.
use a purpose made product. Ie interlux perfection is made for rolling and tipping so it sets up a bit more slowly than awlgrip I'm told to let brush strokes flow out
Apply thinner than you think.
I tipped vertically, not horizontally. While this meant you can see a few vertical ripples, it virtually eliminated sags. i also used the best brush money can buy for tipping.

And before all of that, prep prep prep. And use the products that the paint recommends. sure I spent a couple more dollars on interlux brushing solvents, but is $10-20 really that big a deal when you're talking about this big of a job?

[brankin]

The sterling guide is a must study for the first time painter but with that said, I prefer Awlgrip to roll and tip. The trick I have found that leaves a brush mark free finish, is to roll as thick of a coat as I can with out causing a run. Then very lightly let the tip of the brush glide over the surface in a vertical motion breaking the bubbles in the surface caused by the foam roller. This pulls off excess paint in the tip of the brush so at the end of the brush stroke, wipe the brush on the edge of the tray to remove the paint. Make sure you change brushes every 10 minutes or so because the paint will start to setup in the brush. Have a worker dedicated to keeping a fresh clean supply of brushes ready when you need to change. You will be able to feel when the brush starts to drag in the paint. Then watch the magic fuu fuu juice in Awlgrip do its thing. The paint will level and flow to a finish that in some cases is better than can be achieved by spray.

The Mega yacht builder Feadship, roll and tip their yachts and the result are remarkable. Just remember that Roll and Tip is an art form and these kind of results take years of applying paint to develop.

The best tip I can give the group and this applies to varnishing also. After you clean the brush, store the brush in a can with the handle down and the bristles up. This allows the left over solvents to wick to the base of the brush leaving the tip of the brush supple.

Have fun on your next project. One last point...Awlgrip and Sterling achieved their paint characteristics through good chemistry and I can tell you it has nothing to do with the solvents. Solvents can speed up or slow down the dry time but does nothing to the flowing ability of the paint. Bite the bullet and pay for the price of that chemistry...it will be worth it. I saw a boater last week try to roll and tip with Interlux brightside and it was a disaster.

[CharlieCobra]

Mineret, our yard will let ya haul without letting anybody work on your boat. Matter of fact, the actual yard does NO boat work. It's a contractor and DIY yard. The contractors must carry a 1 Mil liability policy to do work there though.

[minaret]

Originally Posted by CharlieCobra

Mineret, our yard will let ya haul without letting anybody work on your boat. Matter of fact, the actual yard does NO boat work. It's a contractor and DIY yard. The contractors must carry a 1 Mil liability policy to do work there though.

As do several others up your way I believe. I was refering to Seattle when I mentioned we were one of the last yards that does that. I know your only a few hours away though. Some people here do head up to Anacortes or Bellingham for that very reason. Too many yards here try to extort you, you know, if you haul here we MUST do your bottom job at least. If they keep it up the DIY will be dead in Seattle. Not good for business IMHO.

[minaret]

Originally Posted by brankin

The sterling guide is a must study for the first time painter but with that said, I prefer Awlgrip to roll and tip. The trick I have found that leaves a brush mark free finish, is to roll as thick of a coat as I can with out causing a run. Then very lightly let the tip of the brush glide over the surface in a vertical motion breaking the bubbles in the surface caused by the foam roller. This pulls off excess paint in the tip of the brush so at the end of the brush stroke, wipe the brush on the edge of the tray to remove the paint. Make sure you change brushes every 10 minutes or so because the paint will start to setup in the brush. Have a worker dedicated to keeping a fresh clean supply of brushes ready when you need to change. You will be able to feel when the brush starts to drag in the paint. Then watch the magic fuu fuu juice in Awlgrip do its thing. The paint will level and flow to a finish that in some cases is better than can be achieved by spray.

Excellent advice. I gave very similar advice in a much earlier thread here, and it elicited amazement. You take paint off with the brush instead of putting it on! No way! Couldn't be! Nobody wants to listen to the pro's. Vertical tipping? Never! They really tried to explain to me that that's just not how it's done. Do a search and you'll find there are already some good threads on this subject, I know I've written a few pages worth on roll and tip here somewhere. But there's also a whole lot of argument from amateurs who are sure they know what they are talking about. The nature of the web.

The Mega yacht builder Feadship, roll and tip their yachts and the result are remarkable. Just remember that Roll and Tip is an art form and these kind of results take years of applying paint to develop.

Many megayacht builders roll and tip. The scale of the job is just so massive that it begins to make sense. I remember working on Rupert Murdock's Annaliese, a 280' monster just bristling with toys and a massive transom garage. She has a full time paint crew who travel with the boat. Every time they pull up in port for a while these guys paint a section of the boat. I've never seen such an amazing roll and tip crew. The boat looked incredible.


The best tip I can give the group and this applies to varnishing also. After you clean the brush, store the brush in a can with the handle down and the bristles up. This allows the left over solvents to wick to the base of the brush leaving the tip of the brush supple.

Very important. Good quality china boar bristle only. I really like oval brushes for varnish, more payload. Not good for paint for the same reason.

Have fun on your next project. One last point...Awlgrip and Sterling achieved their paint characteristics through good chemistry and I can tell you it has nothing to do with the solvents. Solvents can speed up or slow down the dry time but does nothing to the flowing ability of the paint. Bite the bullet and pay for the price of that chemistry...it will be worth it. I saw a boater last week try to roll and tip with Interlux brightside and it was a disaster.

This I might debate. While what you are saying is essentially true, it is easy to make paint too hot to acheive flow by using the wrong reducer. Some people even insist on using pro-cure x-98 in brushing topcoat, a practice I abhor. Proper mixing for conditions is about 50% or more of acheiving a perfect flow coat, IMHO. I wrote a long diatribe on this here somewhere. So I guess what I'm saying is that while , yes, the magic fuu fuu juice has the chemistry to create flow in the base and converter, you can easily retard that ability through improper mixing for your conditions.

Nice to see another pro discussing paint here. It's funny that someone posted the sterling guide. Those pics are all from the early 90's and everyone in them are VERY familiar to me. Those pics were all taken on the dock at Vic Franks, back in the old days. That was a seminar that sterling hired us to give on applying their paint.

[sailvayu]

Here is another hint for the amateur painters.

If you do get a run or sag use a fine file cut to about 2-3" long glued to a wood block as a finger hold. With this you can file the run level without touching the surrounding finish. this makes sanding and buffing out much easier. You can find these files in the better automotive paint stores. Even the pros get sags from time to time.

Additionally if you have a large area of orange peel you can sometimes clear coat over it and end up with a very acceptable finish if the op is not too deep.

[CharlieCobra]

Originally Posted by sailvayu

Here is another hint for the amateur painters.

If you do get a run or sag use a fine file cut to about 2-3" long glued to a wood block as a finger hold. With this you can file the run level without touching the surrounding finish. this makes sanding and buffing out much easier. You can find these files in the better automotive paint stores. Even the pros get sags from time to time.

Additionally if you have a large area of orange peel you can sometimes clear coat over it and end up with a very acceptable finish if the op is not too deep.

Ha ha, we certainly do. If I'm lucky and catch the paint just right, i can take a piece of tape and lift the majority of the run off so fairing it out is much easier. The issue with sanding runs with anything soft is that the paper rolls over the run and takes paint from around it as well so you end up with a low hill with valleys on both sides. It feels smooth but shows on recoat.

Another trick I used on varnish was to take a very good scraper and shave the run flat prior to blocking and blending. Worked very well on Lady J. It'll work on paint except the hard LPU's like Awlgrip.

[brankin]

To remove a run, take a razor blade and and hold it perpendicular to the surface and lightly work it back and forth across the run always keeping the blade vertical until you have the run close to flat. At that point, you can get a little more aggressive with your strokes. When the surface is flat, buff the surface and it will be hard to see the run. Never try to lay the razor sideways and try to cut off the top of the run...you will end up gouging too deep into the paint film. Do not try this on paint that is not cured for at least 24 hour and never on an Polyester Urethane like Awlgrip. If you try this on Awlgrip, you will have to re-shoot the boat. Use this only on an acrylic like Awlcraft 2000.
Good luck with the repair. Just remember...Do I live with the run, repair the run or re-shoot. If you try this, you have a chance to have good results and on the down side, you have to re-shoot anyway. Might as well give it a shot.

[brankin]

Originally Posted by sailvayu

Here is another hint for the amateur painters.

Even the pros get sags from time to time.

.

This is how we become Pro's. We have had so many runs, dry spots and prep problems that we learned what not to do. Even with all that experience, in my case over 30 years, paint will bite you even when you think you have all the answers and least expect it.

[CharlieCobra]

Especially when you switch to new paint because THAT'S what the customer wants...

[brankin]

Amen

[minaret]

As I posted earlier for the OP, my answer to the run or hanger is to tape it off tight with fineline, no overlaps in the tape, and then use a small hard block with 800 wet to sand the run out. On a really big one I might start with 400 wet and work up, since it will never touch the surrounding paint. Sand till its flush with the fineline and you are hitting the tape on all sides. Then pull tape and finish blocking it out with 2000 grit and a rubber block or foamy. Then polish. This will usually make it completely invisible like it was never there. The only problem I experience is that a really big hanger will sometimes have little microscopic bubbles inside of it, and when you finish it out it will occasionally look like a little line of porosity. But you need to get out the magnifying lens to see it.
Taping out a hanger in wet varnish is a lost art. Glad to see someone else still does it Charlie.

[CharlieCobra]

and then there's metallic......