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CornishPasty
31-03-2017, 18:03
I've been playing around with the GL75 arm for as long as I can remember trying to make a silk purse out of a sow's ear. I don't think its turned out too badly.

https://i58.servimg.com/u/f58/11/73/38/69/p1020910.jpg (https://servimg.com/view/11733869/1600)

https://i58.servimg.com/u/f58/11/73/38/69/p1020912.jpg (https://servimg.com/view/11733869/1602)

I also managed to turn up a push fit bearing housing out of brass. It doesn't leak either :D

https://i58.servimg.com/u/f58/11/73/38/69/p1020913.jpg (https://servimg.com/view/11733869/1605)

Of course I'm bound to say that I'm very happy with the result but I really am :)

https://i58.servimg.com/u/f58/11/73/38/69/p1020914.jpg (https://servimg.com/view/11733869/1606)

Wakefield Turntables
31-03-2017, 18:47
Very nice work Ralph. The only problem I can see is that the diameter of the bearing appears to be ?touching the motor or is certainly very close to it which means all sorts of nasty vibration getting into the bearing and then the platter.

CornishPasty
31-03-2017, 20:12
Thank you Andrew. The bearing does clear the motor ok though it's quite close to the speed control linkage. That's not a problem as it's in the 16 rpm slot in the pic. The housing is 30mm diameter which is as big as I could make it.

Wakefield Turntables
08-04-2017, 09:57
Ralph, have you ever consider removing the speed control linkage altogether and fixing the speed of the Lenco to say 33rpm, of course this mod is useless if you like to play 78s and 45s.

CornishPasty
08-04-2017, 11:55
No not really Andy as I like to have the facility to play at other speeds. I have the speed control rigged to disconnect the idler and when I'm using my Lenco I leave the motor running throughout the session. I also find it easy to fine tune the speed at the control lever and I don't have any speed irregularities when moving the lever back from one slot to another. All other linkages and superfluous parts have been removed and if I thought it necessary I could easily damp what's left. In fact this particular turntable has no damping anywhere yet. That'll get done when it gets put into a better plinth but tbh I'm really enjoying it just how it is right now.

Wakefield Turntables
08-04-2017, 16:18
No not really Andy as I like to have the facility to play at other speeds. I have the speed control rigged to disconnect the idler and when I'm using my Lenco I leave the motor running throughout the session. I also find it easy to fine tune the speed at the control lever and I don't have any speed irregularities when moving the lever back from one slot to another. All other linkages and superfluous parts have been removed and if I thought it necessary I could easily damp what's left. In fact this particular turntable has no damping anywhere yet. That'll get done when it gets put into a better plinth but tbh I'm really enjoying it just how it is right now.

Gotcha! That's fantastic. It's nice when you can just appreciate a deck for what it is. Please dont get my disease of Tweakitis!!!!

CornishPasty
13-04-2017, 01:02
I'm not an obsessive tweaker but I spent a hour or two today making fractional adjustments to the alignment, vta and downforce. I'm happy with the results. I'm only using a 2M Red in the Lenco arm and it really does sound fabulous. I've decided that even though it's sounding so well I'm not happy with the big clunky Lenco headshell so I'm going to attempt to make something more svelte. I'm going to have to do this with hand tools I think. I really need to buy myself a small milling machine as my mate Mick is a grumpy c-nt and sometimes he won't give me access to his. He's a strange chap. Other times he'll do anything for you but when he's in a mood he doesn't like anyone else working in his shop. Never mind, I had a good day yesterday. I found a nice lump of aluminium bar in the workshop just big enough to turn into a full bearing housing instead of like the brass sleeve I made. I'm just waiting for the oilite bushes to arrive and I'll ream out the housing to suit the bushes and then size the bushes to fit the Lenco shaft. I machined the bottom cap out of brass and grooved it to take a neoprene O ring for a good seal. I need to pick up some peek tomorrow to make some thrust pads. Pics later.

brian2957
13-04-2017, 07:28
Your tonearm and bearing mods look fantastic Ralph . I know the GL75 quite well now and I know how difficult it must be to make these parts . I'm still happily using the beautiful headshell and counterweights which you so kindly made me last year . They're a joy to use . I wish I had your skills mate :)

CornishPasty
13-04-2017, 11:19
Thanks Brian. If you should ever need a lighter headshell just give me a shout.
I'm very happy with the mods I did to my tonearm and I was considering having the tonearm bearing housing cnc machined so that others may be able to convert their own arms but I don't think its going to work for small numbers. I'm not really that good a machinist to get repeatable results but I might just give it a go. Practise makes perfect as they say but I'd need that milling machine. I machined this first one with an end mill in my stand drill :eyebrows:

brian2957
13-04-2017, 11:33
Hi Ralph , I'm not sure under what circumstances , or with what cartridge , I would need to use a lighter headshell :)

CornishPasty
13-04-2017, 13:50
Brian, if it works ok with your Shure cartridge then that's fine but I just wonder if it might work better in a slightly lighter headshell, somewhere between a standard headshell at 16g and the heavy one at 22g. I think I might just make another headshell with two removeable shims giving +3g +6g and +9g and maybe I should also get hold of a Jico stylus for one of my M55e carts and have a play. Which stylus did you buy Brian?

Jimbo
13-04-2017, 13:58
I have the Shure M55e cartridge with a Jico stylus but it is the SAS version - very good indeed and compliance is perfect match with the standard Lenco arm and headshell. I also have a NOS N55 stylus for the Shure which sounds very good indeed, however the JICO SAS is outstanding.

brian2957
13-04-2017, 14:32
Im using a Shure M55E Ralph with Jico elliptical stylus.

CornishPasty
13-04-2017, 17:02
Thanks chaps. I also have a very low mileage M97xE with both its own stylus and a standard Jico elliptical stylus. I didn't particularly like this cartridge but I feel I must put some miles on it and see if it shapes itself.

Wakefield Turntables
13-04-2017, 18:53
I have the m55e with the neoSAS stylus and it knocks the older more expensive Shure carts out the water and will leave a stock denon 103 well behind and is probably equal to the ortofon 2m black. Yes it costs a bit of money but it's worth it.

CornishPasty
13-04-2017, 19:02
Thanks Andrew, I'll have a look at the neoSAS. Tbh the DL103 has never done much for me either and I've had a few. I might just pick up another R version though at some time just for the sake of the collection :)

CornishPasty
14-04-2017, 18:16
Ok so this afternoon I swapped out the Red for the xE with Jico elliptical stylus and boy did it take some setting up but I have to say it sounds like it's going the right way. It needs some hours putting on it now.

CornishPasty
04-05-2017, 00:11
I managed to finish the bearing for my L70 today. It's taken me several weeks to get this done, the biggest problem I had was reaming out the oilite bushings to the correct size. In the end I realised that my cheap reamers weren't up to the job. I managed to borrow a decent set from a good friend and that's the next thing on the want list for the workshop. Here's a couple of pics of things so far.

https://i58.servimg.com/u/f58/11/73/38/69/img_2113.jpg (https://servimg.com/view/11733869/1609)
The housing was turned from aluminium for no better reason than I just happened to have a lump that was the right size for the job. The end piece was turned from brass because it can stand a bit more abuse than aluminium. I'm sticking with original spindle because there's nothing not to like about it and it's the best bit of the original bearing. The oilite bushings came from the Bearing Boys and the thrust pad was turned from a length of peek rod.


https://i58.servimg.com/u/f58/11/73/38/69/img_2114.jpg (https://servimg.com/view/11733869/1610)
Nice sideways shot of the completed bearing. I still haven't managed to master this photo hosting thing yet!


https://i58.servimg.com/u/f58/11/73/38/69/img_2115.jpg (https://servimg.com/view/11733869/1611)
Here's the underside of my L70. There's just enough clearance for the speed change at 16 rpm which I'll use to disconnect the idler wheel as I do with all my Lencos.


https://i58.servimg.com/u/f58/11/73/38/69/img_2121.jpg (https://servimg.com/view/11733869/1617)
A shot from the top showing the bearing installed. I made sure there's a well above the top bearing bush so it'll never run dry. Lube is 75/80 gear oil though I might try something lighter after the bearing has had a few hours put on the clock.


https://i58.servimg.com/u/f58/11/73/38/69/img_2116.jpg (https://servimg.com/view/11733869/1612)
Finally one with the platter in place. I was amazed that I got the platter height right first time though I made sure I had room for a thicker thrust pad if I needed more height. All in all I'm fairly happy with result. There is some noise from the bearing housing but it is small and may diminish as the bearing runs in. It's still miles in front of the worn out, sloppy bearing the deck came with.