Speed problem on Triumph A

[Lucius1958]

Lately, I've been having a problem with my Triumph Model A: it plays all right in 2 minute mode; but when I switch to 4 minute, I get some speed fluctuations. Is there anything I can do without having to tear down the upper works again?

- Bill

[fmblizz]

Maybe belt slippage when in the 4 min due to more of a load. If the gears are meshing properly I would first suspect the belt.

blizz

[outune]

Also- Check the set screw on the lower belt pulley. I had a similar problem with my Triumph "A"-- Discovered that the set-screw was not real tight and the pulley was slipping just a little. A quick tightening and all has been fine.

Brad Abell

[Lucius1958]

OK, I cleaned & degreased the belt (it was new when I put it in the machine), reglued the splice, which was gummy, and put it back in: it was now horribly loose. I trimmed the barest minimum and retried it: it was now way too tight. So I had to stretch the hell out of it to get it to fit over the pulleys; I loosened the tension as much as I could, and I tightened the bottom pulley screw. Now, depending on how I adjust the bottom pulley, either the belt crawls up the outer edge of the pulley, causing it to slow; or, if I adjust the pulley a fraction of a millimeter outwards, the pulley jams on something.

I may need to get a whole new belt, and start all over again: it was running fine when I had adjusted it before.

- Bill

[gramophoneshane]

I've never owned a Triumph, so this may be a silly question, but do these also use planetary gears for the conversation?

I've got a home that has been doing the same thing, and after exhausting every other Avenue, mine seems to have something to do the planetary gear when it's changed from 2 to 4 minute mode.
It doesn't seem to be engaging properly, and tinkering with the position of the selector arm hasn't helped either.
I'm thinking there might be some gunk or wear present that's preventing it's smooth operation?
I've been avoiding pulling it down but it's the only way I'm going to find out if I'm right.
Might be worth a visual inspection anyhow.

[Lucius1958]

I've never owned a Triumph, so this may be a silly question, but do these also use planetary gears for the conversation?

I've got a home that has been doing the same thing, and after exhausting every other Avenue, mine seems to have something to do the planetary gear when it's changed from 2 to 4 minute mode.
It doesn't seem to be engaging properly, and tinkering with the position of the selector arm hasn't helped either.
I'm thinking there might be some gunk or wear present that's preventing it's smooth operation?
I've been avoiding pulling it down but it's the only way I'm going to find out if I'm right.
Might be worth a visual inspection anyhow.

The combination gearing for the Triumph is the same as on the Home.
- Bill

[pallophotophone]

Have you checked the condition of the small bearing that the small planetary gear shaft passes through ? There should be no play or slop in the shaft whatsoever - horizontally or vertically. If the bearing is defective, it will
cause the gearing to jam.

[Wagnerian]

You've already been inundated with suggestions but just to add my two-penneth worth...

When in the two-minute mode, the feed screw and the mandrel shaft both rotate at 160 rpm. In four minute mode, the feed screw rotates at 80 rpm and the mandrel shaft remains at 160 rpm. This can lead to friction and hence the sound fluctuations.

As it is quite difficult to lubricate the mandrel shaft with the feed screw still attached, a trick I picked up from an Edison Phonograph Monthly was to tip the phonograph vertically on to its short side (removing the winding crank first, of course) so that the end with the gear change mechanism is uppermost. This then allows one to gently trickle oil between the feed screw and mandrel shaft and gravity moves the oil down the shaft.

All I can say is, it has worked for me on both a Triumph and a Home.

Regards

Tim W-W

[Lucius1958]

So: I got new belting, cut, spliced, and glued it...

Same damn problems. Either the belt is too loose, and slips on the pulleys, or it keeps crawling up the left side of the bottom pulley. Oddly, the only time the belt stayed in place was when I turned it INSIDE OUT. Maybe I should glue the belt inside out, and THEN reverse it? Tried adjusting bearings, etc. etc., but it still refuses to run right. I can't even test a cylinder on it.

I think I'm going to have to tear the whole damn thing down again.

- Bill

[Lucius1958]

Weirder and weirder...

Fiddled with the pulley, the belt, the governor, the end bearings, etc. etc.: now at least the belt is staying in place. However, now when the belt is on, even though I loosened the tension as much as I could, I often have to tweak the upper pulley to get it to start; and when I lower the half nut, it slows to a halt.

I'm not too sure about the half nut, either: the threads look rather faint. I'm beginning to feel like the test pilots in "The Right Stuff":
"I've tried A! I've tried B! I've tried C! I've tried D! Tell me what else I can try!"

- Bill