Warped Plastic Gondola


Paul Hillman
 

I have an older HO 40ft plastic drop-bottom gondola (AHM maybe) that I want to re-detail and letter for the C&EI.

The problem is it developed an upwards hump/warp in the middle. The whole car body warped up about 3/32", while packed away for a long spell.

I think I remember it mentioned on this list about how to heat-up a plastic car like this and re-flatten it out, like in an oven at 100 deg.? maybe?

Any suggestions about how to do this correctly? I don't want to wind up with a melted experimentation on my own.

Thanks, Paul Hillman


Benjamin Hom
 

Paul Hillman asked:
"I have an older HO 40ft plastic drop-bottom gondola (AHM maybe) that I want to
re-detail and letter for the C&EI.

The problem is it developed an upwards hump/warp in the middle. The whole car
body warped up about 3/32", while packed away for a long spell.

I think I remember it mentioned on this list about how to heat-up a plastic car
like this and re-flatten it out, like in an oven at 100 deg.? maybe?

Any suggestions about how to do this correctly? I don't want to wind up with a
melted experimentation on my own."

Paul, can you post pictures of the model?  The real first step is to see if it's
worth salvaging - it it's the old AHM 40 ft gon, I'll be happy to send you a
replacement.  If it's an older HO scale plastic composite drop-bottom gon, it's
not an AHM model, but the old Walthers USRA composite gon.


Ben Hom


Dennis Storzek
 

--- In STMFC@yahoogroups.com, "behillman" <chris_hillman@...> wrote:

I think I remember it mentioned on this list about how to heat-up a plastic car like this and re-flatten it out, like in an oven at 100 deg.? maybe?

Any suggestions about how to do this correctly? I don't want to wind up with a melted experimentation on my own.

Thanks, Paul Hillman

The danger isn't melting the kit... injection molded styrene needs to go north of 420* F before it will actually liquefy. The danger is it will warp worse.

Resin kits often take a set if exposed to high temperatures in the box (like the 120* F + that they can see in a UPS truck). We typically heat them to 120-150* F on a cookie sheet and expect them to lay flat, and they usually do. That's because in the natural state the casting has no residual stresses... it was poured flat, it cured flat, and it really wants to be flat.

Injection molded parts are a whole 'nother animal. They were molded under extreme pressure (up to 30,000psi) and then frozen in place to the shape of the mold. Heating an injection molded part is just asking to have it turn into something resembling either a banana, or a strip of bacon. LOCALIZED heating can be used to bend a part... the theory behind deforming gon panels and the like. But overall heating can yield some really unpredictable results. The best bet is to grasp the ends of the part, and play the center ober the hot air from a hair drier... when it yields, STOP, and see if it will stay when it cools. Then quit. Overall heating will not yield good results.

Dennis


PennsyNut <pennsynut@...>
 

On 18,10 2011 17:14 PM, soolinehistory wrote:

--- In STMFC@yahoogroups.com <mailto:STMFC%40yahoogroups.com>,
"behillman" <chris_hillman@...> wrote:
I think I remember it mentioned on this list about how to heat-up a
plastic car like this and re-flatten it out, like in an oven at 100
deg.? maybe?
Any suggestions about how to do this correctly? I don't want to wind
up with a melted experimentation on my own.
Thanks, Paul Hillman
from Dennis Storzek

The danger isn't melting the kit... injection molded styrene needs to
go north of 420* F before it will actually liquefy. The danger is it
will warp worse.....snip....Injection molded parts are a whole 'nother
animal. They were molded under extreme pressure (up to 30,000psi) and
then frozen in place to the shape of the mold. Heating an injection
molded part is just asking to have it turn into something resembling
either a banana, or a strip of bacon. LOCALIZED heating can be used to
bend a part... the theory behind deforming gon panels and the like.
But overall heating can yield some really unpredictable results. The
best bet is to grasp the ends of the part, and play the center ober
the hot air from a hair drier... when it yields, STOP, and see if it
will stay when it cools. Then quit. Overall heating will not yield
good results.
Dennis
So, let me interject a thought: Is there anyone who has done this sort
of thing? I did try a hair drier once and failed. But that was a
different material. There are so many different kinds of plastics. Look
at all the trouble removing paint.
And I'll bet there are many with ECW kits with warped roofs. Will those
straighten out with your technique? So, again I ask for specific results
from someone who has actually fixed a plastic kit? Details are nice. And
are always helpful for beginners as well as old timers.
Morgan Bilbo, Ferroequinologist and Pennsy Fan!


al_brown03
 

I've straightened out a scratchbuilt styrene boxcar roof, which had warped (due to too much glue on one side), by putting it in a pan of water and bringing it to the boil. I kept it at the boil maybe a minute before turning off the heat. Then I put the roof between paper towels on a flat surface (as if the roof were a strip of bacon), and flattened it with a weight. The roof didn't straighten out completely, but close enough that I could attach it to the car with cement and a few pins.

A gondola is a different shape, of course, which you'd need to enforce somehow. I wouldn't expect it to spontaneously re-assume its original shape. I'm tempted by the thought of removing the car from the hot water, inserting a wood block of the desired dimensions, clamping as necessary, and letting the assembly cool; but that's speculation.

-- fwiw --

-- Al Brown, Melbourne, Fla.

--- In STMFC@yahoogroups.com, PennsyNut <pennsynut@...> wrote:

On 18,10 2011 17:14 PM, soolinehistory wrote:

--- In STMFC@yahoogroups.com <mailto:STMFC%40yahoogroups.com>,
"behillman" <chris_hillman@> wrote:
I think I remember it mentioned on this list about how to heat-up a
plastic car like this and re-flatten it out, like in an oven at 100
deg.? maybe?
Any suggestions about how to do this correctly? I don't want to wind
up with a melted experimentation on my own.
Thanks, Paul Hillman
from Dennis Storzek

The danger isn't melting the kit... injection molded styrene needs to
go north of 420* F before it will actually liquefy. The danger is it
will warp worse.....snip....Injection molded parts are a whole 'nother
animal. They were molded under extreme pressure (up to 30,000psi) and
then frozen in place to the shape of the mold. Heating an injection
molded part is just asking to have it turn into something resembling
either a banana, or a strip of bacon. LOCALIZED heating can be used to
bend a part... the theory behind deforming gon panels and the like.
But overall heating can yield some really unpredictable results. The
best bet is to grasp the ends of the part, and play the center ober
the hot air from a hair drier... when it yields, STOP, and see if it
will stay when it cools. Then quit. Overall heating will not yield
good results.
Dennis
So, let me interject a thought: Is there anyone who has done this sort
of thing? I did try a hair drier once and failed. But that was a
different material. There are so many different kinds of plastics. Look
at all the trouble removing paint.
And I'll bet there are many with ECW kits with warped roofs. Will those
straighten out with your technique? So, again I ask for specific results
from someone who has actually fixed a plastic kit? Details are nice. And
are always helpful for beginners as well as old timers.
Morgan Bilbo, Ferroequinologist and Pennsy Fan!



[Non-text portions of this message have been removed]


Paul Hillman
 

Ben,

Thanks for the "replacement" offer and advice. This model I have is an all steel version. I'm guessing it's an AHM car.

How this all started is; ....Athearn is offering a C&EI, 95300-95399 series C&EI gondola. It is generally accurate only in car-type numbering, otherwise it's "generic". The model has 10 panels and the prototype car had only 8, side-panels. (This was all mentioned in the C&EIHS Volume 29:1 "Flyer" Magazine along with scale dwgs. of the prototype.)

I noticed, then, that I have this old gondola sitting here which has the correct 8 panels, and all of the dimensions are pretty close to the prototype dwgs., except for the "slight" warp it developed over the years. (Don't know when I acquired it.)

It would be a "simple" matter of rebuilding it. I like "kit-bashing" and super-detailing stuff. Also, I am quite nostalgic about these "old" cars that I have which can be made into good models. That's a great amount of "fun" for me in this hobby.

I can send photos of the car but I think it's salvageable if the "warp" can be removed.

Paul Hillman

----- Original Message -----
From: Benjamin Hom<mailto:b.hom@att.net>
To: STMFC@yahoogroups.com<mailto:STMFC@yahoogroups.com>
Sent: Tuesday, October 18, 2011 4:25 PM
Subject: Re: [STMFC] Warped Plastic Gondola



Paul Hillman asked:
"I have an older HO 40ft plastic drop-bottom gondola (AHM maybe) that I want to
re-detail and letter for the C&EI.

The problem is it developed an upwards hump/warp in the middle. The whole car
body warped up about 3/32", while packed away for a long spell.

I think I remember it mentioned on this list about how to heat-up a plastic car
like this and re-flatten it out, like in an oven at 100 deg.? maybe?

Any suggestions about how to do this correctly? I don't want to wind up with a
melted experimentation on my own."

Paul, can you post pictures of the model? The real first step is to see if it's
worth salvaging - if it's the old AHM 40 ft gon, I'll be happy to send you a
replacement. If it's an older HO scale plastic composite drop-bottom gon, it's
not an AHM model, but the old Walthers USRA composite gon.

Ben Hom


Tim O'Connor
 

Paul, I thought every AHM car said AHM in the tooling, so you should
not have to guess. I have a plastic box in the basement with about 100
car bodies including AHM, Revell, Mantua and Tyco gondolas... I agree
with Ben it's probably not worth the energy to heat the oven to fix
as you can probably find a free replacement from almost anywhere. I
am amazed you found a prototype for the model! :-)

Tim O'Connor

Thanks for the "replacement" offer and advice. This model I have is an all steel version. I'm guessing it's an AHM car.

How this all started is; ....Athearn is offering a C&EI, 95300-95399 series C&EI gondola. It is generally accurate only in car-type numbering, otherwise it's "generic". The model has 10 panels and the prototype car had only 8, side-panels. (This was all mentioned in the C&EIHS Volume 29:1 "Flyer" Magazine along with scale dwgs. of the prototype.)

I noticed, then, that I have this old gondola sitting here which has the correct 8 panels, and all of the dimensions are pretty close to the prototype dwgs., except for the "slight" warp it developed over the years. (Don't know when I acquired it.)

It would be a "simple" matter of rebuilding it. I like "kit-bashing" and super-detailing stuff. Also, I am quite nostalgic about these "old" cars that I have which can be made into good models. That's a great amount of "fun" for me in this hobby.

I can send photos of the car but I think it's salvageable if the "warp" can be removed.

Paul Hillman



----- Original Message -----
From: Benjamin Hom<mailto:b.hom@att.net>
To: STMFC@yahoogroups.com<mailto:STMFC@yahoogroups.com>
Sent: Tuesday, October 18, 2011 4:25 PM
Subject: Re: [STMFC] Warped Plastic Gondola



Paul Hillman asked:
"I have an older HO 40ft plastic drop-bottom gondola (AHM maybe) that I want to
re-detail and letter for the C&EI.

The problem is it developed an upwards hump/warp in the middle. The whole car
body warped up about 3/32", while packed away for a long spell.

I think I remember it mentioned on this list about how to heat-up a plastic car
like this and re-flatten it out, like in an oven at 100 deg.? maybe?

Any suggestions about how to do this correctly? I don't want to wind up with a
melted experimentation on my own."

Paul, can you post pictures of the model? The real first step is to see if it's
worth salvaging - if it's the old AHM 40 ft gon, I'll be happy to send you a
replacement. If it's an older HO scale plastic composite drop-bottom gon, it's
not an AHM model, but the old Walthers USRA composite gon.

Ben Hom


Tim O'Connor
 

I got in big trouble with my Dad as a kid when I applied generous
quantities of Testors' styrene cement to the interior of a gondola,
possibly an AHM gondola -- I was fascinated by how the glue caused
the sides of the car to bend inwards and the floor to warp upwards.
I proudly showed it off to Dad (it was his model) and that's when
the trouble started... I recall that it was green, lettered for EJ&E.

Tim O'Connor

Injection molded parts are a whole 'nother animal. They were molded under extreme pressure (up to 30,000psi) and then frozen in place to the shape of the mold. Heating an injection molded part is just asking to have it turn into something resembling either a banana, or a strip of bacon. LOCALIZED heating can be used to bend a part... the theory behind deforming gon panels and the like. But overall heating can yield some really unpredictable results. The best bet is to grasp the ends of the part, and play the center ober the hot air from a hair drier... when it yields, STOP, and see if it will stay when it cools. Then quit. Overall heating will not yield good results.

Dennis


Benjamin Hom
 

Paul Hillman wrote:
“How this all started is; ....Athearn is offering a C&EI, 95300-95399 series
C&EI gondola. It is generally accurate only in car-type numbering, otherwise
it's "generic". The model has 10 panels and the prototype car had only 8,
side-panels. (This was all mentioned in the C&EIHS Volume 29:1 "Flyer" Magazine
along with scale dwgs. of the prototype.)


I noticed, then, that I have this old gondola sitting here which has the correct
8 panels, and all of the dimensions are pretty close to the prototype dwgs.,
except for the "slight" warp it developed over the years. (Don't know when I
acquired it.)”

Tim O'Connor replied:
“Paul, I thought every AHM car said AHM in the tooling, so you should not have
to guess.”
 
True, but this is one of those models that have been copied time and time
again.  Versions of this 40 ft, 8-panel gon model with Dreadnaught ends have
been offered by Varney, Life-Like, AHM, and Walthers, and a couple of AHM/IHC
successor firms that I don’t recall at the moment.  I think the Varney car was
probably first, but I'll have to work the advertising timelines, and frankly,
that's not high on the priority list.  
 
 
“I agree with Ben it's probably not worth the energy to heat the oven to fix as
you can probably find a free replacement from almost anywhere.”
 
I wasn’t kidding – if you really want to do this project, I’ll send you a
replacement model for free.  It really isn’t worth fixing the shell you have
unless you want to satisfy Bilbo’s curiosity on fixing warped shells.
 
(BTW, I’ve had success with using both boiling water and a heat gun – an
inexpensive industrial-grade one I picked up at Fry’s years go which has more
“oomph” than a hair dryer.  The key is working slowly and carefully.  Dennis is
correct – the oven is a bad solution for styrene.  I once had a number of
slightly warped Tichy running boards which I tried to straighten in the oven. 
They turned into cooked spaghetti.)
 
 
Tim added:
“I am amazed you found a prototype for the model! :-)”
 
I am too.  We’ve been looking for years for a prototype for this model, and I’m
a bit skeptical about Paul’s call on this one.  I’ll have to pick a copy of the
reference and see for myself.



Ben Hom


rwitt_2000
 

Paul Hillman wrote: "(This was all mentioned in the C&EIHS Volume 29:1
"Flyer" Magazine
along with scale dwgs. of the prototype.)"
Tim O'Connor replied: (snip) "I am amazed you found a prototype for
the model! :-)"
I recall an article published in the model railroad press about
converting these generic gondola models, AAR class GB, with 8-panels
into general service gondolas, AAR class GS. I cannot recall the
specific reference possibly RMC.

Bob Witt


PennsyNut <pennsynut@...>
 

To All
As for my curiosity, I only posted because there may be hundreds of
those warped plastic kits (like the ECW) lying around in someones work
"to be done" piles. And as I tried to say - Post examples of something
that worked - stating the mfgr, your exact method, etc.
I had tried that hair dryer once and never again. LOL It certainly
sounds logical that an oven is a waste of time, and kind of dangerous,
since it's non discriminatory as to what is heated. The hair dryer does
localize the heat. Boiling water sounds relatively easy because you can
watch it. But again, I ask only for tried and true methods.
But more than any of this, thanks to all who input suggestions and
certainly, Ben, for a very generous offer to Paul?
And as for time. Time is relative. Some people have more than others.
Now, if anyone has any extra, send it my way. Or Ben's. LOL*
*Morgan Bilbo Ferroequinologist SPF PRRTHS #1204


Paul Hillman
 

Well, I'll be durned!!! I finally found the small manufacturer name in the car's underframe, covered with some paint. It was made by, "Bachmann - Made in Taiwan".

In my quick, initial measurements, the ends, width and length are close to the prototype, but the sides appear about 8 inches too tall at 5ft-0 in, instead of 4 ft - 4 in. The C&EI Dwg. calls the prototype a, "LOW-SIDE STEEL GONDOLA".

Isn't it "illegal" to scan the C&EI HS magazine and post it, etc.? But I think if you want to contact Bob McQuown at the C&EIHS he would be glad to provide the prototype drawings, at: president@ceihs.org<mailto:president@ceihs.org>

But, for reference, the proto-dwgs. show:

42 ft - 7 1/8 in Length - Over Striking castings
7 ft - 3 3/4 in Height - Above railhead
31 ft - 0 in Truck Centers
3 ft - 9 3/8 in Railhead to Top of Floor
10 ft - 5 in Width - Over Chords

Maybe the C&EI had another series of gons even closer to this Bachmann model. (They had several different series.) But, if this one will work, and with the "free" or inexpensive offers you've all made, I could build a large fleet of them.

Thanks to all,

Paul Hillman

----- Original Message -----
From: Benjamin Hom<mailto:b.hom@att.net>
To: STMFC@yahoogroups.com<mailto:STMFC@yahoogroups.com>
Sent: Tuesday, October 18, 2011 11:27 PM
Subject: Re: [STMFC] Warped Plastic Gondola



Tim added:
“I am amazed you found a prototype for the model! :-)”

I am too. We’ve been looking for years for a prototype for this model, and I’m
a bit skeptical about Paul’s call on this one. I’ll have to pick a copy of the
reference and see for myself.

Ben Hom


Benjamin Hom
 

Paul Hillman wrote:
"Well, I'll be durned!!! I finally found the small manufacturer name in the
car's

underframe, covered with some paint. It was made by, "Bachmann - Made in
Taiwan"."

Paul, thanks.  I had forgotten about the Bachmann version of this model.
http://ho-scaletrains.net/bachmannhoscalerollingstock/id37.html


"In my quick, initial measurements, the ends, width and length are close to the
prototype, but the sides appear about 8 inches too tall at 5ft-0 in, instead of
4 ft - 4 in. The C&EI Dwg. calls the prototype a, "LOW-SIDE STEEL GONDOLA".
<<snip>>
But, for reference, the proto-dwgs. show:

42 ft - 7 1/8 in Length - Over Striking castings
7 ft - 3 3/4 in Height - Above railhead
31 ft - 0 in Truck Centers
3 ft - 9 3/8 in Railhead to Top of Floor
10 ft - 5 in Width - Over Chords"

8 inches is a lot, but this does present a use for this model, much as we got
some extra mileage from the Tyco gon by cutting it down in height to model 40 ft
D&H gons and their copies on the NEB&W roster.  If the rest of the details and
dimensions are close, it's an esay matter to do the same to the
Varney/Life-Like/AHM/Mehano/Walthers/Bachmann... 40 ft gon.


"Isn't it "illegal" to scan the C&EI HS magazine and post it, etc.? But I think
if you want to contact Bob McQuown at the C&EIHS he would be glad to provide the

prototype drawings, at: president@ceihs.org<mailto:president@ceihs.org>"

Without permission, it certainly is.  Besides, I'm certainly OK with purchasing
a copy of the issue in question from the society - after doing enough of this
stuff for free, the least I could do is kick $12 plus shipping to the C&EI
Society for the effort to publish this work.


"Maybe the C&EI had another series of gons even closer to this Bachmann model.
(They had several different series.) But, if this one will work, and with the
"free" or inexpensive offers you've all made, I could build a large fleet of
them."

Just give the word!  Not only do I have some extras in the morgue, I can scare
up more from the basement in Davision Hall that can be had for a donation to the
club.


Ben Hom