Straightening A Bent Lionel Steam Engine Cab Roof

I remember someone doing this but they applied heat to it ,like a torch .

Not an easy job, diecast could easily break. Nice work.  

Looks great!  I'm very impressed with the improvised tools!

Yes, nice work.  So you didn't apply any heat at all ?   I wonder if heat and how much would or should be used, if any ?

Heat helps, but it still takes time to straighten them.  I don't think I've ever had one that looked that bad, that came out great considering.

More pictures and a description of how the "vise" was made would be useful.

Well done presentation. I do it basically the same way but used a vise with the two pieces of wood just duct taped to the jaws so I can drop the shell in one handed. I always use heat either propane torch or 800 degree heat gun both held some distance away. The diecast should be too hot to touch (sizzle spit). The paint is good to over 400F. If it starts to burn its way too hot. Takes a few heat, clamp steps.

Pete

Could you take a couple more pics of the repair from different angles?  I am just curious how visible the remaining scarring is to the naked eye, from the one rear shot, its hardly visible. 

Excellent work!!

did you apply any heat?

Thanks everyone for the positive comments.  Bobotech, I also am impressed with the improvised tools but, sadly, can't take any credit.  It was all my brother-in-law Spence.  He made and mailed to me, CT to NC postage PREPAID, the one I used in the pics.  Also, I'll post more photos tomorrow as you requested.

GRG, how the vise was made is explained in the PDF attachment.  That with the photo of the vise laying on the table should do it.  Here's a couple more for perspective.

All, I did NOT use any heat.  It might help but I wouldn't know how to use it or take a chance trying.  This is a "cold flow" process that takes time as explained in the PDF!  From start to finish it probably took a little more than 3 weeks.

John

I have been staring at an old 2037 due for a rebuild that has a bent roof trying to figure out how to do it. This is a score to find. Thanks for the info!

Excellent work!  I really like the jig you made.  It's what my father would call, "Usin' yer noggin."

I have repaired them in a similar way except I just cut a wood form for the bottom contour of the cab. I applied heat carefully with a small torch then put the form to the bottom of the bent cab and “formed” it to the wood template with a rawhide mallet(or rubber). Heat makes it form much easier without breaking but early on I got one too hot and melted it so be careful. Good job on repair.

Remarkable that you were able to straighten such a severe bend without heat. The key was patience. I guess it shows that some metals are actually fluids.

Bob

Here's a PDF with your text and the pictures embedded, this little tool is worthy of a complete document.

How to Repair a Bent Cab Roof on Lionel Steam Locomotives.pdf

Updated with additional pictures.

Thanks GRJ.  That was a GREAT idea.

Later this morning I'll be posting the pics Bobotech requested.

I'll keep the Word file at the ready to add the extra pictures.

I remember a story about syrup dispensers.  LA Die Casting made the lid and handle flat, and my employer (I was building an airplane part time for them) told me they tried bending slowly over a mandrel, and it cracked every time.  They went to a "whump" procedure - impact bending - and now you see those syrup dispensers with curved handles everywhere.

Nice job!  They usually break when bent back to original shape.  Then it is fiberglas city.

Bobotech, I took these pics today.  This is how it looks close up

And this is how it looks from a foot away

As I said yesterday, while it's not perfect unless you look really close it's hardly noticeable.  I could probably tweak it a bit more by putting a shim under the corner of the cab for a little more pressure in the vise but I didn't think it was worth the bother.

I edited the PDF to add your additional pictures.  In case you want to make more editorial additions, here's the Word file and the PDF file.

How to Repair a Bent Cab Roof on Lionel Steam Locomotives.docx

How to Repair a Bent Cab Roof on Lionel Steam Locomotives.pdf

When I cut my wood "die" I make the radius slightly larger than the finished radius of the cab roof as it will spring back slightly. That would have gotten rid of the slight droop on the firemans corner. Again, using heat will reduce the time to complete this to about 15-20 minutes vs days.

Pete

Norton posted:

When I cut my wood "die" I make the radius slightly larger than the finished radius of the cab roof as it will spring back slightly. That would have gotten rid of the slight droop on the firemans corner. Again, using heat will reduce the time to complete this to about 15-20 minutes vs days.

Pete

I have a 773 that I purchased recently and it at one point took a dive.  The engineer's side's corner is good, but from about the middle over to that side, it sits a bit lower.  How would I correct this?  Would I use @Norton 's version to make the radius slightly larger?  Dumb question, but how would that work without affecting the good side??

Thanks!

If  you concentrate the heat on the area that needs to be bent the "good side" should not bend.

Pete