# Forum Home Renovation General Odds & Sods  Painting form ply

## bookleaf

I belong to a dog obedience club. In some trialling disciplines there are jumps of various types and heights required.  One form of jump is made from portable metal uprights which have various width boards inserted between them to give various height jumps commensurate to the height of the dog jumping it.  The boards get a battering as they are changed around, thrown on the ground, roughly stored and handled.
The club has just replaced the old boards with new ones made of, what appears to be, Formply.  They are painted white, but several weeks after the boards have been painted they have been slow to cure and remain sort-of tacky resulting in the boards sticking together when stored on top of each other and subsequently having the paint peal off. 
I have been charged with correcting the situation.
I am told the person who painted the boards followed the advise of ??? and applied Penetrol first before painting.  I do not know what paint he used other than to say it was sprayed on.  In all there are 14 boards involved which put together would take up an area of about 1.5 x 2 metres. 
I understand that Penetrol was used as a prep before painting but it may not be a correct prep and has not enhanced paint adhesion and also has contributed to the slow drying/tacky condition.
I think that something like ESP, after complete stripping and sanding may be a better solution. 
Can anybody offer some suggestions on how to re-paint these boards?

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## METRIX

Form Ply is not meant to be painted, it's primary used is as formwork for concrete, it has a coating of either a plastic or phenolic paper and is designed to "let go" of the concrete, this means if you paint it no matter what you prep it with, it will let go of that coating as well. 
The only thing you can probably do is sand off the outer coating revealing the timber ply underneath, then undercoat and paint this, you couldn't even skin it with thin layer of marine ply as the glue doesn't really stick to the outer layer as well.

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## NZC

Probably shouldn't have used formply to start with. I wouldn't think any paint would stick to the film on top without aggressive sanding beforehand. It would probably just be easier to make new ones with marine ply.

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## phild01

I have formply shed doors that I painted with haymes exterior paint, a paint similar to solarguard or weathershield, and it doesn't scratch off.  The trick was to weather the phenolic layer for several years in my case, and let the paint harden.

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## METRIX

I don't know if he can wait a few years  :Smilie:   :Smilie:  
Yes the film face will break down in the elements, it will also break down after repeated uses for formwork.

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## droog

Have used painted formply for backing boards at a rifle club.
Just gave the board a quick sand to scuff the surface and painted with acrylic with no primer. 
No problems with adhesion or drying.

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## Blocker

> I belong to a dog obedience club. In some trialling disciplines there are jumps of various types and heights required.  One form of jump is made from portable metal uprights which have various width boards inserted between them to give various height jumps commensurate to the height of the dog jumping it.  The boards get a battering as they are changed around, thrown on the ground, roughly stored and handled.
> The club has just replaced the old boards with new ones made of, what appears to be, Formply.  They are painted white, but several weeks after the boards have been painted they have been slow to cure and remain sort-of tacky resulting in the boards sticking together when stored on top of each other and subsequently having the paint peal off. 
> I have been charged with correcting the situation.
> I am told the person who painted the boards followed the advise of ??? and applied Penetrol first before painting.  I do not know what paint he used other than to say it was sprayed on.  In all there are 14 boards involved which put together would take up an area of about 1.5 x 2 metres. 
> I understand that Penetrol was used as a prep before painting but it may not be a correct prep and has not enhanced paint adhesion and also has contributed to the slow drying/tacky condition.
> I think that something like ESP, after complete stripping and sanding may be a better solution. 
> Can anybody offer some suggestions on how to re-paint these boards?

  Water based acrylic is not the right product for this job,it will take 4-6 weeks to cure,and will not be hard enough for the rough handling anyway.
Clean the boards and allow to dry,then apply 2 coats of turps based high gloss enamel,allowing 24 hours between coats,then allow 5 days hardening before using.
Regards,
Blocker.

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## bookleaf

Thanks guys for your input.
I have one board that I am going to attack over the Easter weekend as a trial, using a variety of the ideas above.  
I will see how it goes and report back - though it may be a few weeks to allow drying/hardening time.

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## bookleaf

Well, an update after 10 months or so. 
I ended up stripping all the boards I had been given (came off in sheets like stripping wallpaper), sanding and prepping with ESP and applied 2 coats of epoxy enamel paint.  I found this to adhere the best and to have the best knock resistance. During my testing undercoat made no difference to adhesion or durability.
Most boards faired quite well over the last 10 months with only a few places where the paint chipped off. 
I discovered there were more boards than I thought so have spent the Christmas break applying a third coat to the previous boards and stripping and applying 3 coats to the remainder of the boards.  Three coats as the coats are thin and it took that much to cover the black. 
Think we should be right for another year or 2 now.

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## Bros

> Well, an update after 10 months or so.

   Good to hear, hope the dogs are happy with it.

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## bookleaf

They are not if they do not jump high or long enough and hit the jump!!!.

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