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Elizabeth I feel Able should put out a series of blood red hammers. Save us some trouble.

Yesterday I went shopping for groceries, and to a club meeting. The market was up, so I made enough that I did not need to tune pianos.

Sam,
This project I use the 6" pneumatic random orbit as well as many different sanding blocks. This Enduro finish is black with no clear.
Previous project I used a 6" random orbit that has a vacuum attach followed by many hand block sanders.
I have just started to use Target clear acrylic I think it is EM 6000 or something like that.
Like it better than Enduro - sands easier too.
The clear is more clear compared with clear Enduro - resembles nitro lacquer. Very easy to work with and there is almost no layering. Very nice product.

Gene, yes Target is nice stuff. Have u used the spray on filler? It's tricky. Dries very hard. Haven't got the hang of it yet but I like the idea.

Funny - Mirka is a VERY local brand here in the middle part of Finland... the headquarters is just 15 miles away. I know their CEO personally. Didn't realize it was a world-wide brand. Small world...

Well the abrasives they make on a totally open support, (Abranet, I guess) are really second to none when it comes to aspiration, and also they dont clog with the dust so they last way longer than even the special ones (white sheet, auto lubed) for lacquer sanding. Most furniture workers use them there actually (and piano technicians too).

Gene and Sam I am afraid I dont know what are the lacquers (?) you talk about.
What are the products ? or akryl urethane as automotive painters use now ? or something else ? solvent based or catalyse ?) i did not read they where Akryl water based.
I dont know if this is different from Akryl urethane , do you need a heated room ?.

For a help on yamaha polyester (black or transparent) you can use the ones that are sold to repair cars (fiber glass + polyester). Thy are cheap, and can be even used with a brush (but of course sanded ans surfaced afterthat. only horizontal surfaces or they'll flow, but it helps sometime.
The other polyesters (Koenig, for instance) sold for piano and furniture repairs content parafin, so they dont drip as much and can be used more thick, but you have to wash the parafin from the surface with acetone before adding more.

I was told recently that the polyester is often only a primer coat on pianos actually, then a clear high gloss cot is used which is urethane (2 composites catalyser and product)

before then I guess that the last coat was ultra gloss polyester and it is yet the case on some brands)

Issac: www.targetcoatings.com Target Coatings. They are water-based products for furniture finishing. No polyester. I'd like to fiddle with polyester spraying. Saw it done at M&H but can't find a spray equipment supplier. Haven't been back to prowl about their shop and check labels.

I usually keep paper toweling soaked in peppermint oil in the machinery to keep the mice out. 'Forgot it this year in the snow blower, and had to change two belts. Grrrrrr!

Thanks Sam, I'll have a look.
I forget to say that the Mirka "ABRANET" is second to none for hammer shaping. (grit 80- 120- 250)

no clogging ! stay fresh !

It is sold in long strips for the long sanding blocks.

You more or less can see what you are doing thru the sanding "paper" .

Better have your fingers backed with some masking tape so not to hurt them (and it is also a good way to keep the hammers neat and white)

really worth the try.

That one, but I have longer strips I cut to 5 cm large +-

Thanks, I dont spray polyester myself very special equipment, it may be out of dust for a long time, I guess a heated spray room is necessary. (the thinner the coat the longer it takes to catalyse) but I repair polyester with 2composant (resin and hardener). With time I begin to do that correctly , while it is easy to have bubbles or miss the good mix...

The polyester sold for automotives is thin and clear, but it is useful as you can repair trnsparent poly(Yamaha for instance) or if you have the good black dye (very concentrated special dye) you can make flat surfaces with a brush and sand buff polish afterthat. low tech but useful (a friend showed me that lately I did not experiment yet but I've seen the result (grand lid) and was OK).
If not, quality polyester spraying is very expensive (many coats + buffing). styrene is a dangerous product for the health, also.

Have a nice sunday !

Gene, yes Target is nice stuff. Have u used the spray on filler? It's tricky. Dries very hard. Haven't got the hang of it yet but I like the idea.
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No - however, after trying to completely fill mahogany grains I am considering some type of filler. Is it clear?

Just purchased some Koenig polyester for touch up. Black poly with hardener and reducer - will touch up with an air brush. Reducer is used similar to lacquer thinner and nitro lacquer - I will find out soon enough as this is my first attempt.

With Koenig, if it is cold you may warm it a little (not too much as it fasten it) but also mix well the resin, that mean no stirring but rolling slowly the bottle so the bottom can mix with the top - avoid bubbles - live it to rest a while anyway before using it.

To avoid bubbles , after having put th 2-3 dorops max of black stain, stirr to the max, then wait 20-30 sec, dont use it immediately. you will probably see some bubbles then.

Wash the inside of the zone with compressed air then acetone to get rid of the whitened zone due to the sanding (that is why it is better to use a blade to finish the preparation, less white).very smooth cup shape on the edges allow the poly to mix with the other under it.

I mask around the zone with thin braun adhesive tape, that will resist to water sanding and show me when I'll be really almost flat (the thickness of the adhesive only remains.

I make an aperture in a plastic sheet for sanding, to protect around the zone (then no need to cover all around with masking tape. it can be worked with a blade also but it is longer, there are special scrapers for polyester , but I never seen one. the Koenig can be rubbed and polished, in the end it is almost invisible. Nevertheless it is sold more as a reparir product and not a finishing product (not to be sprayed).
That one contains parafin, that have to be washed (aceton) from the surface before sanding or adding a new layer.

It is worth knowing how to use it, I could repair very ugly marks on some grand lids that where really not visible afterthat. the use of a good polish (not full of silicone !) because it add a very thin layer in the end, help to have a glossy surface (protect from dust) and hide any micro defect that is yet on the surface.
good luck : Koenig is the one that was or is yet used for German Steinways. the black dye is very good.

Best

May be you did not buy the same product than me, I use 1 liter resin bottles and hardener in paste plus black special dye.

what is 'reducer ?"

Kamin, I did not state the product or situation correct. I am using Koenig polyester repair on a Schimmel lid. The edge repair accidently penetrated into the undercoat slightly and it is quite soft and will not polish. Rather than continue to do repairs as there is not much finish on the edges, I purchased an Ebony Acrlyic Topcoat from my Koenig supplier for touch up. It has hardener and reducer. They said it sprays on and I assumed it was the same as the polyester finish.

Well it may be more worth the try to ask directly Schimmel which products are used then, could be useful to others.

I never traced a too soft polyester (cannot polish) to that kind of problem, only if I use too much dye or too much harderner paste also.

Very possibly Koenig sell the most up to date products of course.

Please tell us how the Acrilyc top coat grip on the underside finish, that is interesting to know.

the edges are the most difficult part to repair, for sure. Being able to spray with an airbrush may be a must.

Professional polyesters are sold with hardener, reducer and solvent (instructions depend of air moisture and of the use , I have instructional data sheet but never done it myself).

Many colleagues are looking for a polyester to be sprayed by themselves, as I have been told some polish restorers know how to do without a special place.

But to have real professional result and avoid health hazard, a spraying both is necessary, not a cheap thing.

The representatives of the polyester brand when I met him in the shop wher I buy varnishes told me that the top coat could be urethane now, may be he wanted to say Akril Urethane.

But he state also that the top coat was "piano polyester" (mean : very glossy and hard), while the underside was a black polyester primer .

I believe that several finish types will adhear to polyester. A friend used a clear water base acrylic lacquer over polyester and it worked very well on an inner rim. I attempted this with the same water base acrylic in black on the Schimmel lid and adheasion was not a problem. The problem was polishing. There was a distinct line where polyester ended and water base acrylic begin and it could not be removed.
This is when I had a talk with my Koenig supplier. Hopefully the sovlent based topcoat that they supplied will not have this issue.

And you are correct in your belief.Poly can be used as a base for a variety of products. Some however will only produce a mechanical bond.

Gene the spray filler goes on a milky white and dries clear. Mist coats. As u probably know that's the trick with water base. Lots of light coats, enough set up time and it fills quickly. The trick with the spray on filler is the squeege. Spray it on, squeege it across grain to fill pores, set up and spray again. Can't leave ANY pile up along squeege ends because it dried very hard and sand out becomes uneven. Haven't got the routine down to my liking but it shows promise.

I am really lost, I understood that he sold you a water based acrylic product, it is a solvent based top coat, but it is Acrylic as well ? is it what is now used on cars ? But the solvent is non toxic and does not evaporate.

I am not capable to understand the technical words for finishing when in English (furnisher web site) . Too bad, it is as with chemicals the words are sounding similar to mean something different !

Yesterday was my first commercial tuning, unsolicited, not an acquaintance. Went well, was a 1-year-old 42.5" Pearl River. They mentioned that it had a ”sticky key” that failed to exhibit the problem in my presence. Hoping for more to come...

This past weekend I pulled my S&S A out of the paint booth and am reassembling. Will post pics along the way. By first piece.