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Hi all,

I thought I’d be finishing the restore of my Lionel 221 today - rebuild of the e unit and motor and rewiring was all finished perfectly.

During reassembly the head of one of the side rod screws sheared off leaving the screw shaft embedded in the blind driver wheel post. I wish I had noticed the cross threading or weakened screw but I didn’t.

My question for the postwar service gurus is what’s the best practice to recover from this? Attempt to extract the screw shaft from driver, or pull of the old wheel and press on a replacement?

Thanks!

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This’ll depend on how the fastener is broke off. If it wasn’t cross threaded, you can stand a chance of backing it off using a small, sharp pick. Old dental tools come in handy for this type of work. Always pick towards a counterclockwise fashion, as this will aid in spinning the broken fastener in the direction to come out. A tiny drop of penetrating oil can be used as an aid. I see this type of repair a lot, and as long as it wasn’t cross threaded, sometimes I find the broken piece just loose enough to back it out,…when a fastener’s head is broken off, it no longer has pressure against the threads, and should back out with out much fanfare..…..if you’re lucky, it’ll spin out enough by picking to grab it with tweezers or pliers, and finish the job.

Pat

If you have a drill index that contains bits smaller in diameter than the screw body, you can drill the center of the screw, and then use a small jewelers screwdriver jammed into the hole as an 'Easy Out' to back it out.  Left hand drill bits are also around, which would, while cutting the hole, tend to back the screw out as you drilled.  Small screw extractor sets are available, a bit pricey though.  Some are more affordable on Amazon, just make sure the size is smaller than the screws diameter.

@CALNNC posted:

If you have a drill index that contains bits smaller in diameter than the screw body, you can drill the center of the screw, and then use a small jewelers screwdriver jammed into the hole … Some are more affordable on Amazon, just make sure the size is smaller than the screws diameter.

Thanks, if pick extraction fails I’ll go with the drill, etc. I’ve used those extraction sets with mixed luck before. This guy is pretty small, a #3-48 I think, I don’t have an extractor that small, but I do have drill bits small enough a and a 3-48 tap, so maybe after drilling, that tap could clear the threads?

Tough call, …..extractors that small are priced in relative Stupidville, …….the major issue with attempting to drill it out, is the surrounding metal is much much softer than the fastener itself. One slip, and the bit will cut through that cast wheel like a knife through butter…..getting a bit perfectly centered on the broken fastener is the PITA, if you’re going to drill it out, best to be dead on center, ….it’s easier said than done to drill that fastener out, Again, picking at it with a decent pick tool would be the safer bet. If you can get the broken piece to at the very least begin to wiggle, you’re home free, and you just need to pick away at it till it starts to move …..it’s frustrating at first, but patience is key here….

Pat

When working on 221 wheels, you have to keep in mind that early locos have wheels based on the 1664 and later locos have wheels based on the 1666.   Since the 1664 was a four drive wheel loco, the early 221s have unique center, blind, wheels.   I agree with others above, I would be making an effort to remove the broken stub and reuse the original wheel.  Try first to get the broken stub out with various sharp devices. If that fails, center punch and drill. I would drill under size hole first. If it turns out to be in the center, it is easy to enlarge the hole.

3-48 has a nominal diameter of 0.079 inches.  1/16 inch drill bit is 0.0625 and that is the recommended hole size if you are tapping it for the first time.  Amazon has a left hand bit set with that size in it for about $16.  I don't know if the hole is blind or drilled through, but if it is drilled through, then a normal bit when it grabs might just drive the rest of the screw through the hole if the break point has no shoulder on it. Hopefully, the pick will be enough to get it started and maybe you can grab it with a pair of hemostats for the rest of the way.

P.S.  Nothing is more disheartening than breaking a tap, or the Easy Out when trying to remove a screw or bolt.  In both cases you end up learning about the real meaning of the Rockwell Scale of Hardness, and look into building or buying an EDM device.

Last edited by CALNNC

Hi all,

Thanks for all the ideas and conversation. Repair completed successfully. The screw was really wedged in there, nothing to grab and picking at it wouldn’t budge. I then drilled a very fine hole down the center and tried to use various sharp bits in a variety of profiles to extract it that way - no luck. I didn’t want to risk widening the hole by over working it so I bit the bullet, drilled out center of the hole with a #47 bit and was able to cut a good set of threads with the tap that hold the #3-48 hex head screw nicely.

Nice to have saved the driver, thanks again for the advice.

Last edited by christie
@christie posted:

Hi all,

Thanks for all the ideas and conversation. Repair completed successfully. The screw was really wedged in there, nothing to grab and picking at it wouldn’t budge. I then drilled a very fine hole down the center and tried to use various sharp bits in a variety of profiles to extract it that way - no luck. I didn’t want to risk widening the hole by over working it so I bit the bullet, drilled out center of the hole with a #47 bit and was able to cut a good set of threads with the tap that hold the #3-48 hex head screw nicely.

Nice to have saved the driver, thanks again for the advice.

Cool, ….let’s see your work!

Pat

@CA John posted:

Hi Christie,

I'm curious if you were able to drill out the broken screw by hand or did you use a drill press or other alignment aid?

John

Hi John,

Since the part was on the engine, I figured it would just as hard to line the really irregular shapes up level and perpendicular on a press than to cradle the engine, and line the hand drill up by eye. I may be kinda stupid that way, but it worked out this time…

As I mentioned I ended up having to drill twice, once to try to extract the screw from the inside out, and the second time to prep the hole for the tap.

Thanks!

Last edited by christie
@harmonyards posted:

Looks great from here!….you’re hired!….fantastic work!…..you start Monday at 7am sharp!….😉

Pat

Thanks for the support! I wish the top of the hole was cleaner, trying the different tools to extract took out some material there and widened it, but luckily there’s more than enough threaded depth to hold the regular length screw.

@christie posted:

Thanks for the support! I wish the top of the hole was cleaner, trying the different tools to extract took out some material there and widened it, but luckily there’s more than enough threaded depth to hold the regular length screw.

Nothing wrong with it, …having a slight chamfered hole is absolutely fine,…..I would’ve done the exact same thing if it didn’t budge …..drilling is just always the absolute last resort,…..the new threaded hole you made looks precise ….

Pat

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