Printers plate developer

[Ace-Garageguy]

Seems it's a tough problem, well known in the printing industry. From the limited research I've done, it seems apparently the blue coating is "insolubilized polyvinyl alcohol" , which can become very hard even when stored away from light. According to this brief excerpt, "mechanical abrasion" (sanding) is one way of getting it off ...

    " improvements in the photoengraving process have been efiected by using dichromated polyvinyl alcohol as the resist layer, for zinc as well as for copper printing plates. An important drawback to the use of such resist material has been the difliculty of removing the insolubilized and hardened polyvinyl alcohol complex from the metal plate and generally it has been found necessary to resort to mechanical abrasion for such removal, with consequent danger of obliterating sharp lines at the borders of the incised areas. Certain chemical treatments proposed, such as with caustic soda, present problems due to their corrosive action on the metal."

Here are two patented CHEMICAL processes that appear to address your particular problem.

https://www.google.com/patents/US3796603      Method of removing insolubilized light sensitized poly(vinyl alcohol) from a surface utilizing periodate ions

https://www.google.com/patents/US3175907     Stripping resists from printing plates

 

 

 

 

 

Edited April 13, 2016 by Ace-Garageguy

[1930fordpickup]

Tom have you tried just picking up some shim stock? McMaster Carr sells it in 50" and 100" rolls 6" wide. http://www.mcmaster.com/#shim-stock/=11z5euw

No more harsh chemicals just cut and polish.  I cut open a orange crush can at work and it was .004 thick. Just for a reference for you on thickness. 

[misterNNL]

Thanks Andy,I had almost forgotten about soda can stock.There are several finished models in my collection from the 1960's with opened doors that are hanging on pop can hinges.That stuff is just flexible enough for me to bump the door and not break the whole door off.

[1930fordpickup]

Thanks Andy,I had almost forgotten about soda can stock.There are several finished models in my collection from the 1960's with opened doors that are hanging on pop can hinges.That stuff is just flexible enough for me to bump the door and not break the whole door off.

I was discussing your need at work and looking through the catalogs on the shelf to order stuff. I just thought let's see what the pop can thickness is for a reference . We both know how flexible the pop can is not sure how flexible the shim stock would be. We only have brass and steel.  

[misterNNL]

I was discussing your need at work and looking through the catalogs on the shelf to order stuff. I just thought let's see what the pop can thickness is for a reference . We both know how flexible the pop can is not sure how flexible the shim stock would be. We only have brass and steel.  

I followed one of the shim stock links and found thickness from .0001(!) and up but he aluminum stock is listed as"full hard"which is what shim stock is all about anyway being used to either increase or decrease the clearance between metal surfaces.The full hard would be impossible for me to work with for creating tapered and curved segments for the end shells of Airstream style trailers.Some builders can probably pull that off I'm sure,but not me.

[Ace-Garageguy]

.020" soft aluminum sheet, 2X4 foot piece, $9.31

http://www.aircraftspruce.com/catalog/mepages/3003_alsheet.php

[dshue76]

I followed one of the shim stock links and found thickness from .0001(!) and up but he aluminum stock is listed as"full hard"which is what shim stock is all about anyway being used to either increase or decrease the clearance between metal surfaces.The full hard would be impossible for me to work with for creating tapered and curved segments for the end shells of Airstream style trailers.Some builders can probably pull that off I'm sure,but not me.

Most aluminum can be annealed. 

[misterNNL]

How would an average person annual aluminum?

[Ace-Garageguy]

How would an average person annual aluminum?

In general, any metal is ANNEALED by heating it and allowing it to cool. The process is different for different metals and alloys.

Why not just buy soft aluminum?  I'm not getting why this has to be so difficult. 

ANNEALING:     https://en.wikipedia.org/wiki/Annealing_(metallurgy)

Edited April 18, 2016 by Ace-Garageguy

[misterNNL]

Thanks Bill,Somewhere along the line this topic made an unplanned left turn.When I started out I was simply looking for a way to utilize the aluminum plate I already had on hand.That plate has a stubborn surface coating on both sides not allowing me to polish it the way I wanted.As always all those responding are offering every helpful suggestion they can including the choices of abandoning the printer's plate for optional material choices.I still have not decided what I am going to do.I have constructed a simple tear drop trailer as a practice platform for attaching some aluminum plate to see how it looks before moving on to a much more complicated project which will require traingluar shaped and curved segments to form it's outer shell.That is a 1936 Airstream Clipper travel trailer.

  I have a 1935 Airstream Torpedo trailer ready to paint that's complicated shape does not lend itself to the application of any real metal plate at all.That one will be painted MM aluminum plate metalizer.

Edited April 18, 2016 by misterNNL
left out a letter

[Danger]

I utilize the printing plates not as stock material to be used on models, but as the floor and side covers inside my paint booth. I put paper over the printing plate to catch paint and overspray and toss the paper every couple of weeks. The printing plate just needs a quick wipe down to clean.

The printing plates are pretty hardy and can takes spills from any of the liquids I use.

Danger

[MGL]

What about a roll of aluminum flashing from Lowes or Home Depot or a local hardware store if you have one. Cheap, comes in different widths, soft, easy to bend, easy to polish. Should be near the roofing supplies.

[Art Anderson]

What about a roll of aluminum flashing from Lowes or Home Depot or a local hardware store if you have one. Cheap, comes in different widths, soft, easy to bend, easy to polish. Should be near the roofing supplies.

And, soft aluminum in the bargain!

Art

[misterNNL]

Seems it's a tough problem, well known in the printing industry. From the limited research I've done, it seems apparently the blue coating is "insolubilized polyvinyl alcohol" , which can become very hard even when stored away from light. According to this brief excerpt, "mechanical abrasion" (sanding) is one way of getting it off ...

    " improvements in the photoengraving process have been efiected by using dichromated polyvinyl alcohol as the resist layer, for zinc as well as for copper printing plates. An important drawback to the use of such resist material has been the difliculty of removing the insolubilized and hardened polyvinyl alcohol complex from the metal plate and generally it has been found necessary to resort to mechanical abrasion for such removal, with consequent danger of obliterating sharp lines at the borders of the incised areas. Certain chemical treatments proposed, such as with caustic soda, present problems due to their corrosive action on the metal."

Here are two patented CHEMICAL processes that appear to address your particular problem.

https://www.google.com/patents/US3796603      Method of removing insolubilized light sensitized poly(vinyl alcohol) from a surface utilizing periodate ions

https://www.google.com/patents/US3175907     Stripping resists from printing plates

 

 

 

 

 

I finally have an answer to my original question about removing that stubborn coating!A friend if mine's husband works with metal finishes for a living and was willing to work with a sample of my printers plate to help find a solution to this problem.One day later his wife returned my sample with both sides polished to an almost mirror like shine.His method was to sand the surface with 2,000 grit wet/dry sandpaper then polish it with metal polish such as Meguir' s or Mothers using soft cotton cloth.He recommends being very sure to keep the working surface super clean to minimize minute scratches and swirls.

[peteski]

Ah, so he used the good-ol' abrasive removal method. Brilliant!