How can I repair a stripped siderod screw on a 726 engine?

[lionelsoni]

You could drill out and tap the hole for a much larger screw, then drill and tap a piece of a screw of that size for the rod screw. I would use brass for easier machining. I would also consider drilling and tapping all the way through the wheel to avoid blind tapping. You could stop the larger tap a little early to get an interference fit with the plug. I couldn't find the rod-screw size for the 726; but Lionel often used 3-48 screws, which could be a tap size a little hard to find.

[3railguy]

Another alternative is to drill and tap the driver for a heli coil. A Helicoil looks like a spring. They screw into the bigger tapped hole and you screw the siderod screw into the heli-coil. The fit will be just as strong as before and take the pounding of the siderod.

[Anonymous]

The JBWeld looks like the best solution, but I think i'll wait for the super glue fix to fail first. Then I'll check the screw to see if itis stripped or if it's the wheel.

Thanks for all the help, guys.

[Jim Duda]

I concur with RAK's suggestion. We use this in our 180 MPH R/C racing airplanes on both 4-40 and 6-32 size screws with no failures. If it were me, I would clean the hole AND the screw threads as suggested above with a Q-Tip or pipe cleaner and acetone (be careful not to get any on the paint!), put some JBWeld in the stripped hole, assemble the side rod and screw and put the screw back in the hole. Then carefully use a miniscule amont of oil on the shoulder/siderod contact area. Let it cure for at least 12 hours at room temperature. Enjoy!

[Anonymous]

If it is the hole in the driver that is stripped, clean any remnant of grease out of it, then fill it with J.B. Weld Epoxy. Drill and re-tap the hole and screw the siderod back on.

We used to use this J.B. Weld to mount collective pitch bearings on R/C helicopters which put a lot more force/vibration/stress on the epoxied area than your trains will ever produce.

If it is the screw itself, a replacement should be able to be procured from George Tebolt.

[Buck216]

Well I am not one of the more mechanical types but, maybe you could line the stripped hole, sort of like using an anchor in a plaster wall. Here, maybe you could use a small piece of lead or something similar. Lead can also be easily melted and poured into the hole as well. Lead anchors hold screws fairly well in concrete so maybe lead would be strong enough to hold the siderod screw. Some plastic slivers may also work the same way.

[Big_Boy_4005]

Yeah Jim, I believe that screw is common to most of the steamers. If you have access to a lathe, or know someone that does, you might be able to have a new blank turned with a larger diameter stem, then do the tap and die work.

Think about it though, how often do you take the siderods off anyway? If it is really a problem, for the simplicity and the money, a new wheel may be your best bet. Good luck.[8D]

[Anonymous]

Big Boy 4005.

It is a shoulder screw, and I think you are right about finding another screw one size larger.

Thanks,
Jim.

[Big_Boy_4005]

I think the fix you came up with is about as good as you can expect, short of replacing the wheel. That is a shoulder screw, correct? If so, it may be rather difficult to find a larger one.

If the super glue bond breaks, you could try epoxy. Plugging, redrilling and tapping seems like such a headache.

[Anonymous]

I've got a 726 steamer with the Baldwin Disc drive wheels. The siderod screw on one of the rear drivers is stripped out.
I used some super glue as a temporary fix and it's worked so far, but I'm looking for something more permanent. Is there a way to tap this wheel and put in a bigger screw?
Is there a larger screw available from a parts source? I appreciate any help.