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by **BigTbird1974** on Mon Sep 16, 2013 10:28 pm

I know that it's a difficult proposition, at best...certainly not the kind of job I'd attempt on my own, since I can barely weld plain old steel things together without making a h*ll of a mess... :nono:

BUT, I also know that there are some WILDLY TALENTED folks around here, capable of all sorts of amazing feats of metalworking I could only dream of. :2Cool:

So I figured maybe it wouldn't hurt to ask. Does anybody have suggestions/advice/??? on what I could do to fix THIS THING?? It's the mounting arm fitting for one of the RxR lights I brought home recently. (the last pic is what it should look like)

If there's someone here that's skilled in such repairs and might be willing to try, I'd love to hear from 'ya. I'd certainly feel safer putting it in a box and sending it off to one of y'all than I likely would playing 'russian roulette' with picking a local welding shop outta the phone book... :fright:

...at least a fellow Forums member would have a good idea of the function of the part and thus the peculiarities of the task, given that all-important groove that happens to be the location of the break in the first place. :rob:

Of course, I'd take care of all postage expenses plus some form of proper reimbursement for time and materials...?? :scratch:

THANKS Y'ALL, in advance! :thumbsup:

by **mcha9797** on Mon Sep 16, 2013 10:42 pm

I surely can't help, but check out some of your local welding shop's. I had two holes welded/filled in my Novalux signal body with no problems. There are many talented welders out there, just tell them what you need done, and go from there. I was very nervous having someone weld on the Novalux, but it worked out very well!! They will more than likely tell you if they can or can't do the job.

Good Luck!! :thumbsup:

by **khardy** on Tue Sep 17, 2013 7:36 am

Hi Tim,

Cast metal is very difficult to weld because it can fracture more from the heat being applied. A good welder would clean the parts and spot weld. This process would be a little timely considering the size of the piece because after every spot weld, the metal would have to cool naturally before striking another arc.

A suggestion if you really want to keep and use that particular piece would be to clean the parts, find and cut a steel pipe that will fit snuggly inside of the opening. Drill several holes all the way through, tap, install some machine screws and grind the heads off. Fill any cracks with JBWeld. With a new pipe inside for support you would still be able to run the wires for the light. Once all put together and installed, cosmetically it would look the same as the other. Just an idea.

Good Luck!

by **Macsignals** on Tue Sep 17, 2013 7:57 am

Keith has a good idea!! If you're dead set on or need to salvage the cast iron piece, look into welding shops that have experience welding up/repairing cast iron engine blocks.

by **coyttl** on Tue Sep 17, 2013 8:31 am

Like others said.

usually it's called "Brazing", and can be done. I've had to have a couple cast-iron parts repaired for my 1909 Semaphore signal. It cost a pretty penny, but (in my case) was necessary.

by **jab8356** on Tue Sep 17, 2013 5:23 pm

coyttl has it right. You can't weld true cast iron. It has to be brazed. I'm no expert, but the stuff I have seen brazed didn't look pretty when it was done.

by **dkendr** on Wed Sep 18, 2013 7:24 pm

jab8356 wrote:coyttl has it right. You can't weld true cast iron. It has to be brazed. I'm no expert, but the stuff I have seen brazed didn't look pretty when it was done.

Cast iron was commonly used before welding was developed. If you had broken cast iron pretty much all you could do was remove and replace. In places with cast iron pipes that are being renovated, the common approach is to take a sledgehammer and break out the pipes instead of trying to cut them gracefully. The pipe-within-a-pipe approach is good - brazing is a bit more like soldering -- and a heck of a lot simpler.

by **Troy** on Thu Sep 19, 2013 11:39 am

jab8356 wrote:coyttl has it right. You can't weld true cast iron. It has to be brazed. I'm no expert, but the stuff I have seen brazed didn't look pretty when it was done.

I've had luck with welding larger pieces of cast iron. The cast iron bottom of my mailbox was busted into several separate pieces and I welded it back together with a small MIG welder I have. It came out great.

That bracket of yours Tim has that indent on it and you wouldn't want to weld over that and change the shape.

by **BigTbird1974** on Thu Sep 19, 2013 7:43 pm

THANK YOU EVERYBODY, for all the good information and advice!! :thumbsup:

I'm leaning most towards Keith's suggestion of adding an 'inner pipe' to hold the broken parts together, since that would by far seem likely to produce the strongest overall repair. For any that might not have seen how this style of hanger bracket works, the 'round end' of this pc fits into a larger round 'socket' on the elbow that holds the light housing itself, and is held in place by a steel U-bolt thru the 'socket' that catches the 'groove'. The elbow (a 2-pc affair held together with its own large bolt) allows the light housing to be turned side to side, and this U-bolt/groove allows it to be aimed up and down. (and THUS, like we see here, the groove itself becomes a stress point that's likely to snap in two when the whole assembly gets 'dropped'...) :nono:

AND SO, if I did attempt to just weld/braze it -- even if that seemed a success -- I'd very nearly expect it to immediately fracture again as soon as I tried to tighten the U-bolt down on it. :fright:

But now what's gonna complicate matters is the fact that the cast parts are not only typically "rough" inside, but also not quite round inside. Not certain if the inner diameter variation is the way it was cast originally or a result of being 'cranked down' and slightly deformed by the U-bolt over the years it was in service -- but the inner diameter ranges from 1-1/16" to 1-3/16" or so. :Phil:

if only it was plain steel, I'd just cut a little chunk of 1-1/8" pipe (which I found in our scrap metal pile already) and vise/hammer that sucker in there and be done with it... :No:

OH WELL...looks like I might end up finding out exactly how good (or not) I can be with a grinder...? fright:

by **EdT.** on Thu Sep 19, 2013 8:03 pm

There's a great deal of misinformation about welding cast iron floating around out there. It CAN be welded, but requires not a small degree of skill to do so. The key seems to be in preheating the parts before welding.

Find one of the old-school welders in your area and they should be able to help you out. :thumbsup:

The idea of inserting a skeleton pipe inside is a great one and I'd pursue that even with any welding. :thumbsup:

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