Fitting belts to a cassette deck

[Martin Bush]

This question is inspired by the current NAD thread.

I have a Hitachi deck which needs new belts. I have not been able to find any replacements listed in the usual places by putting the model number in (I am at work at present - I will add the model number later if it helps).

So, I was wondering what the pitfalls might be of buying a couple of packs of belts from ebay and seeing what fits?

Is there a way to work out, should I take this approach and get things looking like they are working, if everything is as it should be?

I have replaced the belts on a Phillips reel to reel so feel emboldened. However this was done with full instructions and the correct belts supplied.

[Nickthedentist]

Hi Martin,

What I normally do is use a length of thread to measure the circumference (in mm) of the belt required, then divide by pi to give the approximate belt DIAMETER. Then head to the CPC website and see what they've got in stock. I usually buy a few of roughly the right size and then select the one which fits best, the rest going back into their packs and then into my stock.

They're very cheap and seem to have a great shelf life. I recently installed some in an Akai cassette machine, which I'd bought in the late 1990s. They were still perfect and the machine works beautifully!

Happy to help you as always, but we're moving (to Eynsham) TODAY so life's chaotic.

I've just sent you some data via WhatsApp which might be helpful.

[Martin Bush]

Thanks Nick - good luck with the move! I know Eynsham so I can hopefully get over at some point.

Info on the belts received too

For the benefit of this thread I should mention that the belts are not present. Well, they were, but in bits - thankfully not goo though. If they were there I'd know a bit more about the sizes and where they go.

[emeritus]

Ideally you should use belts of the same profile as the originals, although these days it might not be possible. Where Vee pulleys are concerned, using larger or smaller cross-sections will affect the velocity ratio, but usually this will only matter when the belt drives the capstan, and could be compensated for by adjusting the motor speed.

[paulsherwin]

I do own a couple of sets of the cheap Chinese belt assortments. The quality isn't particularly high, but they're OK for things like tape counter pulleys and tray mechanisms, and the larger ones make it easier to size the main capstan belt and can be used temporarily.

Once you know the belt dimensions you can order from CPC as Nick says. Most domestic decks use a flat capstan belt and the dimensions aren't critical (apart from the length/diameter of course). The belt will ride on a raised area in the centre of the motor pulley.

Changing the capstan belt can be fiddly. It usually involves removing or loosening the flywheel backplate so the belt can be moved between the flywheel shaft and the back bearing.

[Martin Bush]

Thanks all for the feedback.

It sounds like I can bumble my way through with this one.

[Martin Bush]

The deck in question is a Hitachi D-22s Mk2.

For some reason I can't find much info on it online (famous last words).

The one manual I can find is not for the Mk2 but an earlier model. It doesn't appear to give information on belt dimensions though. I will bumble about with some ebay generics and see what I can do.

[Nickthedentist]

Very few manuals did give belt dimensions. A manufacturer's part number is usually all that's provided, and this is of little use now that these machines are so old.

I've never worked on that model, but it looks like a nice straightforward, basic, machine from the late 1970s, when things were still built to be repaired.

[Martin Bush]

Thanks Nick. Yes I think you are right.

The machine came from a forum member as a non-runner and I am keen to get it going. Given its relative simplicity I have a good feeling about this