Reel to Reel tape recorder repair

[dave]

I've an old 4 track tape recorder I'm trying to revive! (Fidelity Argyll Major

4).

The electronics all seems to work just fine and it plays tapes - although the take up spool needs a bit of a nudge to get it going.

The problem is that Fast Forward and Rewind don't work at all. I Guess this is a mechanical problem but don't really know where to begin. Is there a separate drive belt for FF/Rew functions? I've taken just the top cover off and can only see one rubber drive belt. I'm not too good at the mechanical side so don't want to totally destroy it by fumbling about (in other words the more detailed any help the better :-) )

On a related thing, the old tapes I'm trying to play are broken in a few places (they are 40 years old!). Is there some way of splicing them together - or maybe there is a kit I can buy to help me do this? If so I appreciate details of where from.

Thanks

[Harry Bloomfield]

dave submitted this idea :

The mechanics are fairly basic.... Many of these used a couple of rubber drives to provide the FF/Rew function, with a little drag on the spool being unwound from by a light application of the spool brake. Check the drive rubber wheels have not lost their grip and the brake is not dragging too much.

It was quite usual to edit these tapes by cutting and rejoining them. This was done by placing the tapes in a brass (none magenetic) splicing block. The block had a tape guide to ensure the tapes ends were square to each other, a couple of clamps to hold the tape in place, then a cutting grove to guide a razor blade used for cutting. Once cut and surplus tape removed, you laid some special adhesive tape over the join then trimmed the edges.

If all you want to do is repair breaks, you can probably do this without the help of the above using Sellotape (or perhaps even better - thin parcel tape) on the side which does not touch the heads (shiny side).

[sponix]

From memory, there is probably a large, flat rubber idler wheel in there somewhere that is responsible for FF/RW.

As the take up spool needs a nudge it's possible the reel clutches are also worn.

There are kits available on eBay: 5851883417

sponix

[sponix]

Service manuals are still available:

[Dave Liquorice]

ARGH! NOOooooo! Sellotape oozes its adhesive and the drys out. Parcel tape the adhesive comes away from the carrier very easily and probably oozes. If you must bodge I'd use "magic" tape, though that isn't very strong but at least it doesn't ooze and dry out.

Proper editing tape is available "whilst stocks last":

on the side which does not touch the heads (shiny side).

Assuming a non-backed coated tape. Though domestic tapes of that vintage are not likely to be backed. B-)

[Cicero]

large bit of tape without losing any real quality.

Cic.

[Nigel Molesworth]

Is this so you can archive the tapes? Otherwise, why?

You need a splicing block and proper splicing tape, like this:

If you are archiving, then before each tape pass clean the heads with IPA, and it may help to re-optimise the azimuth, especially if they are from different sources.

[dave]

Ahh that interesting. There is indeed a large flat rubber idler wheel that's sitting midway between the two spools. It pivots on a spindle "in a world of it's own"! Nothing else touches it and I can move it from side to side about 1" (maybe less). Should this idler be held against the rotating drive shaft by a spring or something? I can't see anything missing. (I can push it into contact with the drive shaft and then it spins freely.) Quite frankly I can't see how it works or what it does. 8-)

[Harry Bloomfield]

dave presented the following explanation :

A long time ago, but from memory the either the tape spool or the motor would move over as you pressed the FF/Rew. This would bring the motor + idler wheel + spool into a driven position. Try it and see which bit moves.

[Dave Plowman (News)]

You may not lose quality but you'll lose the program material. If it's music, even 1/8th of an inch missing will be very obvious at 3 3/4ips

[Dave Plowman (News)]

Masking tape is probably the best substitute for the real thing.

[Dave Liquorice]

Bit thick I'd have thought, even on the heavy back-coated stuff we are (were!) more used to handling not the thin, non-coated, domestic tape. Masking tape dries out as well, I'd say it dries out quicker than sellotape.

I must admit to being rather shocked that 1/4" editing tape is "whilst stocks last" at Canford. Where is me zimmer frame!

[sPoNiX]

Yes, it only moves and makes contact in certain modes.

If it's slipping you can sometimes effect a temporary repair by roughening the tyre with sandpaper-useful to confirm the fault.

sponix

[Nigel Molesworth]

Like the heads, you can also clean it with IPA.

[dave]

I have some very old tapes with "nostaglic material" on them. I just want to play them so can get them onto CDR. I could actually buy a recorder that works - but have this one and it's interesting to me to see if I can make it work again (have some blank tapes to experiment with).

yes - thanks I bought one last night on ebay for previous posters link.

Will do that. May also put a brief .mov file up so show what the mechanicals are/not doing :-) Just off to take another look.

ps I also bought a copy of the service manual online from a posters link.Heck shows my age - I actually know what those valves are!!!! . Total cost so far inc the recorder, £12.! :-)

[Nigel Molesworth]

Note that recording is a whole different ball game and requires much more in the way of setting up (must do azimuth, bias, levels etc).

I'd make it play back reliably, transfer the tapes and dump the lot.

[Geoffrey]

Beer?

[Nigel Molesworth]

Don't mind if I do. ;-)

[dave]

Well, I got the thing working again. In case is if some future use to someone:

It turned out both diecast arms (one for FF one for Rwd) were seized solid to their shafts. It looks as if the grease had solidified. To get them off I removed the circlip at the base of the pulley shaft and they slid out. (Watch out to catch the shims). Remove the circlip from the diecast arm pillar and remove it. Easier said than done though, that bit. One diecast arm I managed to lever off with a screwdiver, the other I think would have snapped if I'd used any more force. So 20 seconds or so with a blowtorch and the thing slid off very easily (melted the grease I suppose). Cleaned all the bits and used a tiny drop of a light oil on the relevant bits then reassembled (it only has to play the tapes once - I hope). Switched on and everything worked fine.

Thanks for all the fb.

[Chris Bacon]

That is highly commendable. Effall use to me, but Well Done for psoting your solution.