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Discussion Starter · #1 · (Edited)
Good Morning!

The cab on my 2460 crane car has 2 cracks. Both appear to be, "Stress Cracks" from the use of the 2 boom, elevating wheels.

What would be the best way to repair the crack and create a stronger backing for those areas?

Also, do you think those flat, plastic toothpicks would work as replacements for the broken wimdow panes?

The cab was painted inside and out. Should I do the same thing, or just use a primer on the inside?

Thanks for all your help!!:D
 

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Jim,

I'd defer to those more experienced in repairs, but here are my thoughts. First, get one of those auto repair kits that have the thin, fiberglass windowscreen mesh and bondo-style goop that works with it. Use this to reinforce the inner walls behind the cracks, so as to strengthen the wall and better distribute future stress. After that dries, use your fingertip to fill the crack from the outside and smooth it over.

As for the windows, toothpicks would work, but they are tapered and may warp. If it were mine, I would do this. Take a blade and shave the inner edges of the window frames to remove all vestige of bars. Then, cut oversized pieces of either clear styrene or glass and cement them from the inside to cover the openings. By going oversized, you take the silicone cement or whatever you use out of sight and you end up with shiny, glass windows in the doors, single-pane instead of 4-pane. If you really like 4-pane, black wire dividers can be glued over the inside of the window frame before you mount the glass.
 

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Discussion Starter · #3 ·
I Can Do That!

Reckers, excellent suggestion:)

I might even be able to do it without screwing it up:laugh::laugh:

What do you think about "scoring" the window plastic on the outside, and using some heavy, black thread, run thru modeling glue? I'd like to have the panes.

The other question that remains is, should I paint the inside of the cab?
 

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Jim,

Pretty interesting / wild to see the cab in its "virgin" clear state. I would have never thought that's how they were made.

I agree with Reck's idea of building up an oversize patch on the inside of the cracks. In the marine world, we would call this a "doubler plate" ... it adds glue/bondage area, and helps to disperse any stress loading.

Speaking of which, cracks on any structure are notorius for spreading further at the point of highest stress concentration ... and that's usually smack dab at the end of the crack.

One way to stop this (i.e., relieve the stress concentration) is to drill a small, smooth hole right at the end of the crack. Doing so will create a "soft" ending to the crack, with no clear stress concentration path for the crack to propogate. You can fill the hole in with some plyable filler (like caulk) prior to painting, so you won't see it on the finished product.

As for window panes, I would think that you could slice some thin strips of a flat plastic with a straight edge and a very sharp single-edge razor blade. Or, your LHS might even have some small plastic extrusions that are "C" or "U" is cross-section (but rectangular, not curved) that might add some more depth and realism.

Glueing any plastic is tricky, though, as I'm sure you know. Many adhesives won't stick to certain types of plastic, and it's hard to look at a plastic and know what type it is.

Test some scrap pieces, first. Any lightly sand/roughen the out (hidden) edges to provide more "grab" for bondage.

Good luck!

TJ
 

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A clear shell. I would just add a tab of super glue and fill it with blinking LEDs!!

The lights would distract any imperfections.

Before I got into stripping paint, a tender shell was multi colored like the Partridge Family Bus. I am thinking of doing just, that but I forgot which one it was!
 

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Reckers, excellent suggestion:)

I might even be able to do it without screwing it up:laugh::laugh:

What do you think about "scoring" the window plastic on the outside, and using some heavy, black thread, run thru modeling glue? I'd like to have the panes.

The other question that remains is, should I paint the inside of the cab?
You'll do a good job of it, Jim. I think the scoring idea is good, but you might try just inking in the score instead of the thread. I think the thread would work, too, but I'm lazy---I'd try to use ink or paint in a "wipe on...wipe off" manuever to just fill the score. Threads will eventually break, but the score won't. Either way, you'll do a fine job of it. :thumbsup:

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TJ,

You mean I had an idea that actually works? *L* I took note of that 'soft-ending' the crack with interest: I can see how that would work, and it's an idea to hold onto. Thanks for sharing it!

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A clear shell. I would just add a tab of super glue and fill it with blinking LEDs!!

The lights would distract any imperfections.

Before I got into stripping paint, a tender shell was multi colored like the Partridge Family Bus. I am thinking of doing just, that but I forgot which one it was!
T-Man, if he's gonna do that, he needs to add a lil guy inside, sitting on the commode!
 

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Discussion Starter · #7 ·
Great Responses!

I just might have to incorporate all your ideas!:)

TJ, so the drilled, caulked holes(2), wouldn't be "Hard Set?"

I'm thinking perhaps a, "Polka-Dot Pattern", with LED's and a guy sitting on the can:laugh::laugh::laugh:
 

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Jim,

To be clear, I'm not saying that you HAVE to drill holes at the end of the cracks (not that I have any real power, mind you!) ... I'm just saying that if there's any chance that the cracks might propogate, drilling small holes should prevent that. Maybe something like 1/16" diameter, or even a bit smaller if you can center your drill bit on the crack ending.

In terms of fill material, I'd think anything that's softer / more pliable than the plastic itself would allow enough flex that you would avoid buildup of stress concentrations in the plastic itself. That's what made me think of a caulk ... either latex or silocone based ... both paintable.

Now, there's certainly an argument that if you bond a strong, rigid "doubler plate" to the back side of the cracked areas -- with a decent amount of overlap to uncracked areas -- that the double plate would act as a strong-enough stress path, with no propogation of the cracks.

I guess it all depends upon:

a. what might have cause the cracks? Hard impact? Fatigue from minor / normal use? Distortion with temperature and humidity?

b. whether any of those "inputs" might continue, going forward.

Sorry to babble on, but the engineer in me is rattling on.

In looking at your pictures again, and if it was me doing this (which, of course, it's not), I would:

1. Add a doubler to the crack at the end of the cab. No need to drill hole, as there's all ready a big hole in the casting itself.

2. Add a doubler AND drill a hole at extend of the crack in the side of the cab.

Sorry to babble on ...

TJ
 

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Discussion Starter · #9 ·
TJ, that's not, "Babbling", that's help and information. Be a pretty boring, useless place if there weren't people like you, ready to help, on any need or question that came up!!!!!

Thank You! :)
 

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You'll do a good job of it, Jim. I think the scoring idea is good, but you might try just inking in the score instead of the thread. I think the thread would work, too, but I'm lazy---I'd try to use ink or paint in a "wipe on...wipe off" manuever to just fill the score. Threads will eventually break, but the score won't. Either way, you'll do a fine job of it. :thumbsup:

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TJ,

You mean I had an idea that actually works? *L* I took note of that 'soft-ending' the crack with interest: I can see how that would work, and it's an idea to hold onto. Thanks for sharing it!

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T-Man, if he's gonna do that, he needs to add a lil guy inside, sitting on the commode!
Sure, you can set a slow flash so it shows with a light.:)
 

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Discussion Starter · #11 ·
What's next?

T-Man, I'm thinking Reckers will want me to add a bar, Black lights, a pole a some dancers:laugh::laugh:

I'm not sure I'm ready to learn about wiring led's:eek: I have enough trouble with color coding the wire(I'm color blind), I can just see me with all the color coded diodes and capacitors:D
 

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Hey---you call it a Club Car!:D Barbie's Sidetrack Tuck-a-Buck? With a big sign out front that says, "Ashes Raked Here"?:laugh:
 

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I checked out a "Club Car" once. Didn't last long, though ... easy come, easy go.

(drumroll, please ... badda bing!)


(We degenerate again, my friends ... we degenerate again ...)
 

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I checked out a "Club Car" once. Didn't last long, though ... easy come, easy go.

(drumroll, please ... badda bing!)


(We degenerate again, my friends ... we degenerate again ...)
Obviously, you didn't have enough $1 bills!:D
 

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Discussion Starter · #19 ·
hmmmmmmmmmmmmmmmmmmm! Screw mount holes, love "Bondo!:D
The cab looks pretty good, and all the window frames are there. I just might......:)

Thanks TJ!
 
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