TECH - Plastic is there a way to flatten out warped plastic pieces?

[Ry]

Just wondering if anyone has come up with an idea as to how to flatten
out warped pieces of plastic. I know we all have seen plastic pieces
warp from the heat of the bulbs but is there a way to get these to
flatten out again? I though about using a heat gun and slowly heating
the plastic on the opposite side of the painted side but am unaware as
to the repercussions. I tried searching on RGP but didn't find
anything in looking under flattening plastic. Thanks!

[Lloyd Olson]

Search again. Lots of info out there. You might do better on search groups
than search RGP. I like the put the plastic between 2 sheets of glass and
set out in the sun and let the sun flatten them. LTG :)

"Ry" <mes...@hotmail.com> wrote in message
news:6df2eeb3-bb79-4af9...@v2g2000vbb.googlegroups.com...

[Chris Hibler]

Here ya go...
The weather here in St. Louis has been beautiful the last week or so
but it's still warm enough to flatten plastics.
http://www.team-em.com/FlatteningPlastics/Procedure.htm
--
Chris Hibler - CARGPB #31
www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm

[mgk]

what's up, this is the good stuff!

[thaiisl...@yahoo.com]

On Sep 1, 8:36 pm, mgk <overlookedo...@yahoo.com> wrote:
> what's up, this is the good stuff!

I'm not sure we have enough sunny days up here in Seattle for that to
work, but willing to give it a try.
Randy

[Ry]

Thanks all!

[rplante]

You can also use the oven method as described on the Mr. Pinball
Repair Tip Archive.

http://www.xmission.com/~daina/tips/pub/playfieldTips.html

- Flattening warped plastics

The sun procedure is safer but the oven method faster and always
available. Plus it gives you that adrenaline rush of bringing your
plastics back from the brink of destruction to factory perfection.
Now thats the thrill of victory!

Randy P.

[cy2td]

I've used the oven method many times and it works great.just don't
answer the phone if it rings.

[morales.y...@gmail.com]

I just used some boiling H20 to fix a water container HDPE 1 that had gotten too hot in the car. Worked pretty well. I guess it depends on type of plastic and melting point.

[Kerry Imming]

I put mine in a 200 degree oven for about 8 minutes. I use parchment
paper on a cookie sheet. Put a heavy book on them when you take them out.
http://user.xmission.com/~daina/tips/pub/tip0018.html

Someone should have a link to their method of putting them between two
playfield glasses and leaving them in the sun all day. Safer but slower.

- Kerry

[Kerry Imming]

On 4/18/2017 7:45 AM, Kerry Imming wrote:
> I put mine in a 200 degree oven for about 8 minutes. I use parchment
> paper on a cookie sheet. Put a heavy book on them when you take them out.
> http://user.xmission.com/~daina/tips/pub/tip0018.html
>
> Someone should have a link to their method of putting them between two
> playfield glasses and leaving them in the sun all day. Safer but slower.
>

I found the link on PinWiki:
http://www.pinwiki.com/wiki/index.php?title=Pinball_Restoration#Flattening_warped_plastics

But the team-em link isn't working. It does have a better description
of the oven process.

-Kerry

[seanspin...@gmail.com]

In addition to Kerry's links, I'll provide the one I use which noone ever seems to mention, but is safer than the popular oven method, but not as safe as the sunshine method. First written up here by "harry w" in 2000:

https://groups.google.com/forum/#!searchin/rec.games.pinball/flattening$20plastics%7Csort:relevance/rec.games.pinball/rLrthJPevnA/bXwZ6aEy50oJ

Getting the pieces of glass that fit your over is probably the reason not too many people propose this, but it's so much easier than the cookie sheet oven method(and safer), it's well worth the extra cost and bother to me...

Sean

[John Robertson]

Archive.org is your friend!

https://web-beta.archive.org/web/20150401032330/http://www.team-em.com/FlatteningPlastics/Procedure.htm

You can often find old pages that have left the internet there...

https://www.archive.org - and plug the URL into the WayBack machine at
the top!

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

[Kerry Imming]

On 4/18/2017 9:06 AM, seanspin...@gmail.com wrote:
>
> In addition to Kerry's links, I'll provide the one I use which noone ever seems to mention, but is safer than the popular oven method, but not as safe as the sunshine method. First written up here by "harry w" in 2000:
>
> https://groups.google.com/forum/#!searchin/rec.games.pinball/flattening$20plastics%7Csort:relevance/rec.games.pinball/rLrthJPevnA/bXwZ6aEy50oJ
>
> Getting the pieces of glass that fit your over is probably the reason not too many people propose this, but it's so much easier than the cookie sheet oven method(and safer), it's well worth the extra cost and bother to me...
>

I like the glass idea since it's flatter and sandwiching the plastics in
would help. However, 2 hours sounds like a long time even at a low
temperature.

- Kerry

[seanspin...@gmail.com]

Two hours might be overkill - I've never experimented with shorter times. I tend to err on the safe side, so generally I do this in the evening, then turn oven off and let them cool right in the oven overnight. And I even forgot one time and left the oven on "warm" all night - so I turned the oven off in the AM, and when I got home that night the plastics were fine.

It takes longer, but I like that I can forget about it and the plastics won't get damaged...unlike the quicker over methods where you watch them and wait for them to flatten. With my forgetfulness, I feel more comfortable this way.

The only problem I've had, and it's very slight, was I learned I need to keep the glass clean since one plastic stuck to the glass one time after I'd done many sets. There was no damage to the plastic...it popped off fairly easy, but it worried me, and I started cleaning the glass before each use and it's never happened again.

Sean

[Kerry Imming]

On 4/19/2017 6:08 AM, seanspin...@gmail.com wrote:
>
> Two hours might be overkill - I've never experimented with shorter times. I tend to err on the safe side, so generally I do this in the evening, then turn oven off and let them cool right in the oven overnight. And I even forgot one time and left the oven on "warm" all night - so I turned the oven off in the AM, and when I got home that night the plastics were fine.
>
> It takes longer, but I like that I can forget about it and the plastics won't get damaged...unlike the quicker over methods where you watch them and wait for them to flatten. With my forgetfulness, I feel more comfortable this way.
>
> The only problem I've had, and it's very slight, was I learned I need to keep the glass clean since one plastic stuck to the glass one time after I'd done many sets. There was no damage to the plastic...it popped off fairly easy, but it worried me, and I started cleaning the glass before each use and it's never happened again.
>

Good to know. Also, I think it would be good to clarify the oven
"LOWEST setting" as less than 200 degrees. I'll have to experiment.

Have you ever had any plastics shrink? A couple times I've had to
slightly enlarge a hole, but it may have also been other changes when I
put the playfield back together. I'm guessing no if you heated a set
all night and they were fine.

- Kerry

[seanspin...@gmail.com]

Yes...absolutely below 200 degrees. It will only work if your oven has a "warm" setting. I understand some don't.

I've never had any shrink that I can remember...I *think* the only times I've had to enlarge holes is with new repro PF plastics that are not always exactly right. But I could have, and just be blending those memories together.

Sean