Dealing with planking

[Pajo]

Hi everyone,

I have just got up to dealing with my mini playfield as part of the refurb. I'm doing on my TZ and have discovered that it has some cracks that I assume are what people refer to as planking (see the photo). 

I've seen a few threads now asking about planking or cracking on pf's so I was wondering if people could share how they ended up dealing with the problem and how effective what they did was. 

I'm guessing that it would be good to have the pf clearcoated, rubbed back and then re-coated so it would be great to hear from the anyone who has experience in dealing with this.

Thanks

[Retropin]

Yep - correct,

Planking is caused by the timber on the PF shrinking and expanding ( either way).
Yours has shrunk causing the artwork to crack and raise  as the two sides push against each other.

How you tackle it depends on how bad it is, sometimes you can tape either side of the line and rub back to smooth then touch up.

If you CC then rub back you have to keep doing it till youve built up enough CC to cover the raised cracks... can be quite a few coats and sometimes heavy CC looks odd.

If its in one area then you can stencil off to a black line and just CC that area, rub back etc... saves doing the whole PF

[spliffsecond]

Hey,

Here is a before and after,
in the first image the original clearcoat has been sanded with 600 grid
and you can still see the planking and ballmarks



after two layers of automotive 2K this is the result,



it needs another layer to fill up the insert damage, but you get the picture
the two layers are sprayed in an interval of one month to let the playfield really soak up the clearcoat, then it gets sanded and a new layer is sprayed

grtz
free

[Pajo]

Thanks for the replies everyone,
Spliffsecond that's a really impressive result.  Was the first sanding with the 600 grit to remove the original clearcoat from the ridges?

[spliffsecond]

Hey,

Thanks, i've got 10 playfields going for other people, finished 4 already.

Sanding with 600 grid is to give the new clearcoat something to adhere to.
It helps also with leveling but more leveling is achieved with multiple coats and sanding inbetween.
It is dangerous to sand to much before clearcoating because you can loose artwork, especially around holes and the borders.
All sanding is done with an orbital sander, apart from the borders wich are finished manually.

I normally put up to 4 heavy coats for leveling, they all get sanded back to almost nothing just to level out the playfield and
then 1 normal coat that gets sanded with 1200 - 1500 - 2000 and then polish to give a nice shine.

I have no photo of the end result (i forgot to take pictures) but here is one i did before, already posted this one in my introduction



hope this helps you
grtz
free

[pinball god]

Hey Spliffsecond, do you recommend that he attempts clear costing to solve his problem or are there other factors to take into consideration?

[spliffsecond]

Hey,

since the marks from magnet play are deeper than the planking ,
i think 3 or 4 coats of clear will solve the problem
sand between coats to level, you don't want a big layer of clear in the end, just enough to protect.
The playfield is'nt that big either so it won't cost much to do the clearcoating.
Meaby eltimbo can make an offer for the clearcoat process.
In Belgium i would do it for 40€ all in. I dont know how expensive clearcoat is Down under?

What other factors to consider? I dont know?
It won't be that easy to find a good (better) replacement.

grtz
free

[Pajo]

Thanks for the help everyone, your suggestions saved the day.  I'm very happy with the way it has turned out so far.  It's hard to capture the detail on a high gloss finish so I have only attached a picture taken after the fourth coat straight off the gun.

I approached a couple of local body shops and talked with the spray painter.  One was happy to do the job on the basis that I did the prep work and he sprayed the mini pf as an add on to when he was clearcoating other work.  We ended up doing four coats a week apart with no baking.

I sanded using 1000 grit wet before the first coat and after the first two coats, then 1200 grit wet before the final coat.  Each time I used prepsol and compressed air to clean before and after sanding and then waited a couple more days before getting the cc sprayed. 

I just have to decide now if I'm going to block the 4th coat and then buff it.  There is a slight uneveness to the final coat around one of the inserts so I'm thinking I probably will do it as it will be a good learning exercise.

Oh and the cost was a total of $20 for the four coats, it would have been crazy not to try it out at that price!

[el_timbo86]

Great result Pajo!!

For $20, you should be absolutely WRAPPED with the finished product 

[Pajo]

Thanks Timbo, I am wrapped with it hence my trepidation at blocking and buffing something that already looks pretty good in order to chase something that is even better.  I loved saving something that isn't being made anymore.

[Strangeways]

Geez - That's what I call "value for money" !

Keep the spray painter's number handy - he could help you out with full clearcoats later on down the track !

Great results.

[ktm450]

Great result, bargain price