Polishing a pitted flywheel

[Dave Plowman (News)]

There are so many variations in the way the various drives work I doubt anyone knows them all.

[Steve Firth]

When were you elected the language policeman for the newsgroup, fucknuts?

[Steve Firth]

All no. But in context it's easy to work out which type Danielle was talking about. And it's easy to tell that LoudMouth didn't have a clue.

[Frank Erskine]

If it's a flywheel driven at a constant speed, a smaller diameter (hence circumference) will propel the tape less distance for each revolution.

[Bob Minchin]

No Frank - sorry but you are wrong. the deck has a belt drive and so the flywheel rotational speed will increase.

Bob

[Rod]

She.

At least, I assume that Daniele is female.

[Dave Baker]

You are a rude and churlish person who I have no interest in squabbling with A) because it's Xmas and B) because I gave up doing that many years ago on Usenet after realising it was pointless and there's always someone new who wants to troll or bicker. If you don't mind I'll just pop you in the killfile instead and talk to the grownups, some of whom are no doubt familiar with the extent of my engineering background.

[Frank Erskine]

Ho hum. As Dave B suggested above, we're talking, aren't we, about a flywheel, NOT a pulley. The capstan motor rotates at a constant speed, driving the pulley, hence the flywheel at a constant rotational speed. If we reduce (by grinding, turning or whatever) the diameter of the flywheel its circumference will also reduce. If, as _you_ suggested above, that the Teac deck drives (is not driven) on the periphery of the flywheel, then the resultant tape speed will be reduced.

[Martin Bonner]

A reasonable, but wrong, assumption. He is Italian, hence the odd (to English eyes) spelling.

(Note: You are not the first person to make that mistake on this group. He wasn't offended last time; he almost won't be offended the next time it happens either.)

[Steve Firth]

You proved that you didn't know what you were rattling on about. Like most LoudMouths, you assumed instead of thinking. And if your skills with a kill-file match your other talents you'll be reading this.

Heck, you're too dumb to realise that Outhouse Excess doesn't have a kill file.

[Steve Firth]

He.

[Dave Plowman (News)]

Perhaps you should check out Dave's site - his engineering expertise isn't in question. And well engineered tape recorders don't use rubber band drives anyway. That's reserved for the bottom of the market.

[Dave Baker]

As God is my judge I had no idea this was a male we were trying to help :) There should be a LOL in there I suppose. Look it up on Google.

[Dave Baker]

It's Daniele not Danielle. Maybe you should spend more time reading and less time shouting angrily at other people :) The missing L is significant.

[Dave Baker]

With respect to your electrical expertise which vastly surpasses mine I'd say that filling with body filler would lead to any drive belt abrading some of that out and it getting into the rest of the works. I think no one is still sure what part of the mechanism we are being asked about here but if the pits are not functionally detrimental I'd leave them alone. Once the covers are back on no one is going to be any the wiser.

[Rod]

My mistake - thanks for the pleasantly worded correction. :-)

[Bob Minchin]

Still wrong as I understand it Frank. The flywheel is both a flywheel and a pulley for the flat belt from the capstan motor. The belt runs at a fixed linear rate and drives the flywheel periphery. In the centre of the flywheel is the capstan, which in turn drives the tape. Danielle is talking of polishing the flywheel periphery thus reducing its circumference. So in a unit time, the same length of belt will rotate a (marginally) smaller flywheel slightly more revolutions and hence the tape will run faster.

tape speed capstan diameter ________________ = ________________ belt speed flywheel diameter

I can see that there is a different interpretation of drives/driven in what I wrote above and so is ambiguous. I meant that the deck drives the flywheel periphery. At no time did I think the tape would be driven by anything other than the capstan.

Bob

[Fred]

I think this is one of your saddest moments. In the past I've always respected you posts but in this case you've hit rock bottom. I have no intention to go into the semantics of flywheels, belts and pulley. You're both grasping on so little information it's unbelievable. We still don't have a clue whether it's significant the flywheel has pits or if it's made smaller will alter the speed of the tape. You're both pissing in the wind upstream. I prefer downstream myself, then it less likely to come back and haunt me.

[Steve Firth]

oooh reduced to sniping at typos, you must be desperate.

[D.M. Procida]

Right, there seems to be a certain amount of confusion and trouble arising from this.

What's pitted is the capstan flywheel, i.e. the flywheel pertaining to the capstan. It's on the capstan shaft, inside the machine.

The flywheel is driven by a flat rubber belt, in turn driven by a pulley on the capstan motor.

I have absolutely no intention of dicking around with the surface of the capstan.

No-one is a moron, f****it or idiot for not understanding this first time.

When I say the flywheel is very lightly pitted, I mean very lightly pitted indeed. It's not so much the pits themselves that concern me, but their very slightly raised edges. These are what I'd like to polish down.

In any case, what needs to be polished out are very tiny superficial blemishes. Probably they don't affect the sound at all - the flywheel must weight about 750g, just for a start - but it's possible that they induce a tiny amount of vibration in the captsan's rotation.

The tape recorder is a Teac A-3340, a semi-pro four-track from the early

1970s, and truly gorgeous.

Daniele