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Well, I have this Edison Home cylinder machine up and running. But the feed screw doesn't move the half nut. Seems to me that either the half-nut's threads aren't meshing correctly with those of the feed screw, or the half-nut is worn out and needs replaced.

Is there a way to determine whether nut threads are meshing correctly with screw threads? And to adjust if not?

bangster

This can be a very sensitive adjustment, but first you will need to figure out what is happening.

A few things to look for are make sure the feed screw is spinning when the carriage in down in the play position. If the clutch is not fully seated in the 2 or 4 minute position the feed screw can stand still even while the mandrel is spinning.

Make sure the half nut is in contact with the feed screw when the carriage is down in the playing position.

Is the feed screw and mandrel turning but the carriage is not moving, if you here a clicking sound the carriage is probably the problem, it's sticking and not moving freely.

With the carriage in the down playing position try moving the carriage with your fingers, it should not move if the half nut is adjusted and in good condition as well as the feed screw.

Just a few things to look for while you're setting up and adjusting the half nut.

Larry Crandell

Thanks Larry. I'll copy this advice and save it. But it turns out to have beeen a false alarm. This time when I tried it, the carriage traveled nicely.

bangster

But now I have a question on a totally different topic. I was scolded for starting too many new threads about the same machine, so I'll stick with this one.

The machine has an annoying thump when running, which I've traced to the #4 gear, the one that drives the governor. Each thump coincides with one revolution of the gear.

I would suspect a bad tooth in the gear, but I can't find one. However, the shaft has a great deal of slop where it passes through the plates. If this were a clock, I'd install new bushings. It's easy because clocks have brass plates. This puppy has cast iron plates. Is there a way to re-bush something like this? Is it ever or often done? Is there a source for new bushings? Or should I ignore the slop, and look somewhere else for the thump?

bangster

You may have a crack in your 19 tooth brass pinion in your gear cluster. It is a common problem.
Dave

AHA! A crack. hadn't thought of that. I'll check it out. is Ron S. likely to have a replacement? Is gear removal especially difficult?

Tnx,
bangster

HI Bangster,
Carefully examine the brass pinions in your gear cluster. If you have a drill press, it can be used to press that brass pinion off, but usually they are so cracked that they are broken or spin freely. The new ones can be pressed on using an arbor press or a drill press even. Ron sells a style that slides right on and is held in place with a set screw. I usually file a flat spot on the shaft for the set screw to bite onto.

Check that the governor is not hitting anything. It may need to be slid up or down on its shaft to avoid an obstacle.
Dave

Thanks. I need to get clear on terminology. There is only one brass gear. In clockspeak it's a "wheel" (big gear) rather than a "pinion" (little gear). It drives the governor and is on the same shaft with the pulley. Is this the one we're talking about?

The pinion in question is about ½-inch in diameter, and about ⅜" wide across the teeth.

Not sure of it's location in the total gear-train, but it's the only one this size.

They do crack, then split, often during winding or play, causing the machine to suddenly unwind with a "bang" then the whizzing of the gear-train at high speed. It is VERY alarming if you're right next to the machine.

My Home B did this during a demonstration at a Christmas party several years ago.


Ron Sitko makes an excellent replacement, that secures with a set-screw.


As for governor shaft bearings through the end-plates, I believe Edison used female bearings secured to the plate with a perpendicular set-screw for installation / adjustment... if the holes in the bearing slugs are hogged-out, then bearing replacement is in order.

If indeed the governor pivots run in the cast plate itself, then boring-out and installing some sort of bushing is necessary.

I'll look for that pinion.

My unclarity. The governor runs in nice little bearings. The other shafts run in holes in plates.