PDA

View Full Version : Pete's Lenco GL 75



symon
13-04-2009, 21:42
Following on from the experiences of Beechy, I managed to get a Lenco GL 75. It's a bit shaggy, so I've cleaned it up a little but a lot more needs to be done.

First, some piccies:
From the top:
http://farm4.static.flickr.com/3622/3433643087_845236730b_b.jpg
http://farm4.static.flickr.com/3367/3438820963_e23a181a66_b.jpg
http://farm4.static.flickr.com/3392/3438820955_25dc2c3672_b.jpg

Underneath:
http://farm4.static.flickr.com/3583/3438820975_e1d7e09fc5_b.jpg
http://farm4.static.flickr.com/3300/3438841281_44d90f3ce7_b.jpg
http://farm4.static.flickr.com/3579/3438841285_e5c7151a66_b.jpg

The wheel:
http://farm4.static.flickr.com/3394/3438841287_7d76989b8b_b.jpg
http://farm4.static.flickr.com/3337/3438841311_3cca739eb1_b.jpg
http://farm4.static.flickr.com/3593/3438841327_d4c3e26e53_b.jpg

I have a couple of aims with this. The first is just to get it working so that I can hear it. The second is to do some rewiring. The third will be putting it in a new plinth.

The first aim is not as easy as I would like. The two tonearms I have both have rubbish tonearm wire - both have been cut very close to the arm so I can't connect them to the phono cables. So, first job is to rewire the tonearm! Having two tonearms becomes a bit more useful here as I can use one to experiment on - beginning with how to take one apart.

The second aim will be helped by my local B&Q (closer than Maplin) - who sell two core cable. Not sure what to do about the phono cables yet.

The plinth should be relatively easy after all that - especially as I will be following Beechy's lead and using butchers blocks to do the job.

So, here begins my first steps into audio diy. I feel as if I have bitten off more than I can chew.:mental: But, I want to learn how to do this stuff, and no better way than the hard way. I'm hoping to call on the wealth of experience here and hoping you'll all be patient with my frequent very basic questions!
:cool:

DSJR
13-04-2009, 22:10
The arm internal wires are fairly heavy gauge as tonearm wires go, but should still be serviceable ? The external wires to the amp have been done already. Don't forget to slacken the red motor transit screws and ensure the motor floats freely as best as possible.

The idler looks like a mid period one. The early ones had a solid plastic (?) inner and the later ones had four or five holes cut out of the inner. Carbon Tetrachloride was suggested to clean the motor pulley, underside of platter and the rubber tyre, although I've used switch cleaner solvent with no worries. Make sure to clean the under edge of the platter too to prevent the platter brake from squeaking loudly on switch-off....

Regarding arm alternatives - I wonder if one of the Notts Analogue ones could be made to fit the hole? The price would be prohibitive though I suspect. I still think the L75 arm could be breathed on to good effect and if the arm/cart resonance is "only" 8 Hz with a Shure M75-ED, then there are many good carts under a ton which the arm should safely handle I think..

symon
13-04-2009, 22:36
I should point out that I have never taken a tonearm apart, let alone a Lenco one. So, I have no idea which bits come apart and which bits I should be trying to take apart!

DSJR
13-04-2009, 23:06
I don't even know if the socket can be removed from the lenco arm pipe...

if you look at the rear of the arm under the rear counterweight rod, you'll see s screw. remove this, together with the U shaped washer it holds. If the arm cables are free, you can then lift the arm pipe and bearing-top off the arm pillar proper. This exposes the almost certainly knackered knife edge blocks and allows you to see the underside of the headshell socket, which may be bonded or riveted on, rather than screwed as jap arms are. watch the internal yellow arm earth wire, as stripping this is a nightmare to correct IIRC.

If the arm is well and truly shagged, other samples can be got cheaply enough, so all is not lost. I rather like the look of the GL78 headshell too, with its holes in the top. I understand the GL85 shell fits too.

symon
13-04-2009, 23:34
Hmm - I'll take some photos of the arms I have. But, from what you have said, and looking at them, I think you may be right about them not be re-wirable. Which means getting another arm. That'll teach me to go buying something without fully understanding what I need!:doh:

alb
14-04-2009, 06:23
Plenty of advice based on good experience here.

http://www.lencoheaven.net/forum/index.php

I'm also in the process of doing up a Lenco, and these guys have already covered all the angles.

symon
14-04-2009, 10:52
Yes, I'm going to post there soon as well. I've had a look around that great site but I've not found too much on tonearms yet. The general advice seems to be to replace it. But, I'm a contrary bugger and would like to hear what the original sounds like before moving on.

symon
16-04-2009, 15:59
Well, I'm not getting very far, so far.
I have taken some photos of the arms I have, but they are next to rubbish so I need to try again.

For now, though, I'm still puzzling over the possibility of rewiring the arm. The arms I have are both slightly different, but I suppose the mechanics will be the same for the both of them. My first guess is that the end of the arm which the headshell plugs in to might be removable. Does this sound right?
Logic suggests that the arm had to be wired in the first place! So, how was it done? Any clues?

Dave, I did read your post, but I'm not sure I understand it. Perhaps photos will help. I'll get onto that shortly.

I'm very puzzled (and slightly frustrated!)

DSJR
16-04-2009, 16:19
Usually, the socket can be removed from the arm pipe, but I don't think it's possible with the L69 and L75 arms, as the socket looks bonded or riveted on. same with the arm earth tab, which seems to be riveted into the pipe. The headshell wires are easily replaced, however. As you can see, the wires from deck to amp can easily be replaced too.

symon
16-04-2009, 16:28
Yes, and I can see how they can be done and am happy that doing so should be simple. My problem is with the wires coming out of the armpipe. For both arms they are too short. So, I'm trying to find out how to get round this without buying another arm.

The other problem I will have is with the earth wire - which looks like it is soldered to the armpipe (oops, that what you just said!), so I need to get me a soldering iron soon as well.

Beechwoods
16-04-2009, 17:42
Peter - just seen your posts over on Lenco Heaven. I have no experience of rewiring a L75 tonearm unfortunately. If anyone can offer assistance I think the Lenco Heaven folks can, if no-one here can help.

Fingers crossed for you.

symon
18-04-2009, 22:36
Still no further response beyond the possibility that the end of the tonearm is soldered on. So, I took some better pictures which will help me ask two questions.

Here are the tonearms:
http://farm4.static.flickr.com/3613/3453260901_938c4049bd_b.jpg

Question 1: Is there a way of getting this off? If it is soldered on a) how do I tell? b) does that mean I have no chance of getting it off:
http://farm4.static.flickr.com/3371/3454076108_2cfc7e30a6_b.jpg

Question 2: If I can't do a proper rewire, what can I do with what I have to get one of them working? Can I join new wire on to what is already there? If the answer is yes, how do I do it?
http://farm4.static.flickr.com/3383/3454075430_eb8b8b2c97_b.jpg

I can honestly say that one of the things I have now learnt is to not buy spare parts without knowing all you need to know about the spare part! :doh:

symon
19-04-2009, 18:17
Back to question 2! Will it work if I get more wire and attach it to the stubs of wire in the picture above?

Beechwoods
19-04-2009, 18:27
Only if it doesn't impede the movement of the arm. So you'd need to make sure that the extensions were connected to wire that was free of the bottom of the arm where it joins to the top plate. This might be possible with the longer of the two sets you've got. The extension should be similarly lightweight 'tonearm' wire, and the soldering should be sparing, and insulated sparingly with lightweight silicone shielding, so the joins don't short with each other.

Ideally it would be best to replace the whole length, but that does depend on how successful you are in dissembling the arm.

John
19-04-2009, 18:28
You might as well go for it Symon nd then lets us know how you get on .Will it work, should do but time will tell as Nick sats be careful not to let the wire impeade

symon
19-04-2009, 19:20
I can't get the arm to separate. I have two, as you know. Well, now I have one! So, this leaves trying to use what I have by extending it with new wire.
The wire on my remaining good arm probably doesn't extend beyond the bottom of the post. So, I would have to join them probably somewhere in the middle of the arm post. We'll see. Need to get wire and a soldering iron first. I was half wondering if I could just wrap the new wire round the old and seal it with tape? I know this is a crude bodge, but would it work?

Beechwoods
19-04-2009, 19:34
It would work, but maybe not for long, and more than likely you'd get crackles and noise as the arm tracked across the record. Careful and sparing use of solder would be a lot better, and less likely to cause resistance to the movement of the arm like tape would.

If you run into trouble I could give it a shot - it sounds like I have more experience at soldering than you (though I'm no expert!). Only trouble is I'm away on work Tuesday and out of the country on holiday for a week after that, so wouldn't be able to do it til start of May :(

Perhaps one of the DIYers here could do the job for you? It'd only be a quick thing to do with the right equipment, steady hands etc. And postage etc would be cheap and easy... providing you covered costs to and fro...

symon
19-04-2009, 19:39
Thanks for the offer Nick. My soldering experience is somewhere between never and maybe once at school! :lolsign:

But, I want to learn to do this, and have some old guitar leads that I can use to learn/practice on. So, I guess my next steps are to get a soldering iron, some solder and some tonearm wire.

I'm a bit frustrated, and annoyed with myself for buying something that doesn't really work (too late now to return it). Well, I've learnt my lesson.

I can feel a new thread coming on devoted to the joys of soldering! :eyebrows:

symon
19-04-2009, 19:48
And, to be honest, I'm getting close to just buying another arm which definitely has long wires!

Beechwoods
19-04-2009, 19:50
At least now you know the right questions to ask the next time one crops up on that auction site!

symon
19-04-2009, 19:51
There's one up now and I can see the long trailing wires in the picture ;)

symon
24-04-2009, 21:34
Well, arm bought, bodged in and no sound - apart from a loud hum! :steam::confused:

So, I'm very frustrated and not thinking straight.
I'm learning very quickly that I am not very good at DIY!
I have two problems - loud him (probably a rubbish connection between the ground wire an the arm)
- no sound! Probably wired it in wrong.
I know nothing about tonearm wire. I'm not sure what to do now or how to explain the problem. Will try again tomorrow when I can think a bot more dispassionately about it.
Grr!:(

symon
25-04-2009, 18:14
Well, I've fiddled and bodged a bit more with no further results. Just the humming (which gets much worse if I decouple the wire that connects to my pre-amp).

So, I'm out of ideas and beyond the extent of my knowledge and common sense.

I should admit here what I mean by 'bodge'. The only thing I have to connect loose wires is sellotape. So, that is what I have used to connect the wire from my arm to the wire that is already in the machine and connected to the bit which connects to the phono plugs.

:scratch::confused: