Cylinder "Stuck" in one place

[benjaminh]

Here are some pictures of the feedscrew; it does have some pitting, and the pictures show the worst of it; do you think it needs to be replaced?

[ambrola]

It looks good to me. Does the feed screw turn when the reproducer is up? It will be the half nut or the 2,4 minute gears. There is a little screw on top of the feed half nut bar that you need to turn clock wise to move it down, and counter clock wise to loosen. Put the reproducer down and turn that screw until it is barley touching the feed screw. I check mine by trying to move it and as soon as it don't move, try it there. Here's a picture of the adjustment screw marked in red.

[benjaminh]

The problem is definetely the half nut; it is worn in half (it is in two pieces). I was just wondering if I need a new feedscrew as well, since it is slightly pitted in some places.

[FellowCollector]

Benjamin, It's difficult to tell whether your feedscrew is good with the blue tint that's applied to the picture. But, what I can tell you is that if your feedscrew has pitting or the very fine "threads" are otherwise compromised by oxidation, deep scratches, gouges, etc then the carriage could and will definitely have a problem with getting through the area that is compromised. The feedscrew on an Edison Home, especially, must be in good functioning condition and no amount of weight or fine adjustment on the carriage half nut will get through a "bad" section of the feedscrew. Unfortunately, the feedscrew design on the Edison Home and Triumph leaves the very fragile threads unguarded and I've always felt it was a poor design since it's right on top and out in the open. Any oxidation or dropped object can easily find its way to those fragile threads.

Anyway, if you are able to share a better picture that shows your feedscrew in a natural color it might help us to see what you see.

The half nut is simple to find and replace but the feedscrew could be part of the problem as well.

Doug

[benjaminh]

Here are some pictures without the blue tint. These are the places with the pitting. Besides the places pictured, the feedscrew seems to be in good condition. I am thinking though that is might have trouble feeding in some of these areas; what do you think?

[FellowCollector]

Upon close inspection of the feedscrew using the second picture it appears that the feedscrew threads have been compromised (damaged) by oxidation. My guess is that this is at least some of your issues with the hanging of the carriage. If your half nut is bad then you will certainly want to replace it and that will take about 2 minutes but the feedscrew damage may be irreparable. You might get lucky and be able to bring back some of the integrity of the threads in the damaged area by running a full size nut with the same exact pitch and size as that of the feedscrew - but my recommendation would be to look for a good replacement 2/4 minute Edison Home feedscrew. This, of course, presumes that what I'm seeing is oxidation damage and not gunk. The half nut on an Edison Home is a single nut and therefore the "threads" of that single nut must be in contact with "good" feedscrew threads to navigate across the feedscrew. The Triumph, luckily, has a better designed dual half nut assembly so damage such as this can sometimes be overcome provided one side of the dual half nuts is contacting "good" threads on the feedscrew.

Doug

[ambrola]

I agree with Doug, it looks like it has been cleaned and the pitting is hard to see but it's there.

[benjaminh]

Here is a picture of the half nut. As you can see it is worn into two pieces. However, when I adjust one piece so that it is properly contacting the feedscrew, it does seem to feed fine, even over the slightly damaged parts of the feedscrew.

[PeterF]

That is really impressive.

Now don't you wish you'd seen that during cleaning, rather than taking everything apart? But certainly you will learn about your machine when trying to put it back together. We all have to start someplace.

[phonogfp]

Holy smokes!

In 48 years of collecting, I've never seen that!

Ummm...yes... Try replacing that half-nut and see if your machine's performance doesn't improve...

Posting that photo at the outset of this thread (or your other thread in "Yankee Trader") would have made diagnosing the problem (or at least the machine's major problem) much quicker.

There's no guarantee that your feedscrew is serviceable (especially after grinding its own threads into the half-nut bar), but a new half-nut may be all you need. You can find sources for your Home B half-nut here:

viewtopic.php?f=8&t=195

Ron Sitko or Wyatt's Musical Americana are particularly recommended.

George P.