High Desert Goldring Lenco GL75 project

[kenwood61]

[ COMPLETED 02 October, 2019 ]

[UPDATE to setup on 20 Feb 2023 ... see on page 30]





















So many L75 projects have similar titles that I thought I'd give some geographical context for mine so it stands out  

This is not my first rodeo. But it is my first idler drive turntable. My current table is my Dad's AR XA that is highly modified. I was able to get some good help when I got to a point where I didn't feel confident in finishing off that deck, so I was able to rely on Steve Frosten to deliver a finished table that I have been enjoying for years. I have enjoyed three other turntables as my second deck. These include a Thorens TD 160 MkII, Technics SL-1300, and then a Technics SL-1600 that I rewired, and was actually a really good deck. The SL-1600 was my last deck and I sold it to make room for an idler drive table ... which happened after a buddy of mine in the UK started harping on about Garrard turntables. When he realized I did't have the money to jump on something like that, he was quick to point me to Lenco. Through the following weeks, he helped me search out a Lenco and I bought a Goldring Lenco GL75 off the auction site for about $65 USD. It was located in the UK, not too far for my buddy to pickup and strip off the bad stuff, before shipping to me. This was about TWO years ago.



I recently decided it was time to get off the pot, so I started in earnest to deal with the one thing that was holding me back. The motor. I'm in the U.S., and I wanted to get 60 Hz motor. After asking around, a fellow AKer offered me a good deal on a L70 motor out of a Bogen B62. I have it and in unserviced form, it is surprisingly smooth and quiet. Actually, it's quieter than my AR XA motor. So I can only imagine what servicing will do. I have the service instructions (from LH) and supplies, so I will be servicing both of my motors soon. I'll keep my UK motor just in case. Thanks Joe R!

Being a longtime member of Audiokarma, I have started threads on builds for other gear where I learned, and hopefully gave back a little. I can already tell in my short time here, that LH will be no different. Another AKer (thanks Bill) has been very helpful getting me moving in the right direction and we agreed that it's time for me to start my thread here so I can develop my plan, get feedback on some of my ideas, and document my build in a way that will hopefully be helpful to someone else. In case you want more of my back story, feel free to view my introduction on LH at http://www.lencoheaven.net/forum/index.php?topic=24967.0

Rules of my thread ... I will use this first post to update specs so that nobody has to read through pages just to learn the current direction and spec. I haven't really done this before, but I will do my best.

------------------------

What I have:

• GL75 top plate + platter, w/speed selector assembly
• Rega RB202 tonearm with 303 stub/counterweight*
• L70 motor, w/new capacitor ... Vishay VY1 392M (X1 760, Y1 500)
• Norbert idler wheel + axle
• Werner's axle upgrade (collar)
• ceramic bearing
• SRM Tech Platter Damping Ring
• Pathe Wings Cork/Rubber 2mm mat
• nose screws/nitride ball bearings
• Collar/Cap, Top Plate Clamp Ring, and oilite bushings from Jolly
• JA Michell 3-point VTA adjuster, silver
• JA Michell TecnoWeight ... wow!!!
• Rega 202 arm rewired and spiffed up by J at Audio Origami
• Cardas 4x24 phono cable
• KLE Copper Harmony phono connectors
• Rega M DIN M male phono plug + S DIN E female phono plug
• Schurter power vandal switch
• Schurter IEC fused chassis jack (#6200.2100)
• Schurter power cord
• Schurter IEC Boot
• PEEK thrust plate
• new screws for speed selector ... M2.5mm x 6mm Hex Drive Flat Head (black oxide) #91294A014
• black oxide hex drive screws for Rega tonearm with washer/nut (M4 x 30mm)
• s/s hex drive screws with T-nuts for securing pan to plinth (8-32 x 1")
• AC hookup wire, Cerrowire™ Type SPT-2, 18 AWG white lamp cord from Home Depot, rated 300V and 105˚
• air hose for the idler arm

*Questions + Decisions to make (I will add/edit to this info as time goes by):

Tonearm
Rega RB202 with RB303 silver end stub and counterweight. JA Michell 3-point VTA adjuster makes the plastic base look so much better, plus you can see it serves a purpose. Got my Superflex Litz wire, Cardas tags, clear shrink tubing from KAB USA, and am waiting for some spray can straws (10") so I can design my own isolated routing scheme inside the arm.

Arm board
I have a bunch of Oregon Black Walnut from Goby Walnut http://www.gobywalnut.com/index.htm. It is local to my state, and I feel that this build should use local woods. My arm board will be 3" diameter and visually sit on top of the deck ... no inset. I will most likely never change the arm on this table, so if I create a mounting hole in the deck that allows enough movement with the armboard, I can set it and forget it. Since I will use a lathe for these, I plan to cut a variety at different thicknesses so if I go from stacked platters to a single platter, I can change the armboard. I have the thought of using some kind of thin damping material if I can find something black, that is easy to cut to be just inside the outer edge of the armboard for a clean look. I will devise some way to fasten and adjust the armboard position from underneath ... unless a better idea comes along.

Top Plate
I finished cutting and smoothing out the pie pan months ago, and without any protection, the metal is clean as a whistle. No rust. So once I'm done handling it — during the fitment process with the plinth — I'll do final smoothing, apply stickers in original positions, AFTER I spray satin black.

Main Bearing Assembly
Serviced and installed Jolly's collar/cap upgrade and Werner's PEEK thrust pad ... and ceramic bearing. Beautiful!!

Motor
Motor will get serviced after I don't need to dry fitting during plinth construction.

Power switch
I have a 19mm vandal power switch in stainless to mount in the corner of the speed selector plate corner of the top plate. Carl was nice enough to offer up an extra switch that is the perfect size for my build. Thanks Carl!!

Plinth

Specs:

• Size: 18"w x 15"d footprint
• Top: Atlas Cedar solid slab (2.125" thick)
• Base: South American Walnut (5.5" wide x .875" thick)
• Finish: Formby's Tung Oil, 5-6 coats (don't remember exactly)

The top "plate" is a 2.125" thick Atlas Cedar slab. It is cut. The "base" will be a frame structure that is 5.5" tall. Corners will be mitre cut and glued with biscuits and I will reinforce the corners with solid wood. I will ad a cross brace out of Black Walnut and once I know where my "cavity" needs to be, I can add material (weight). I have plenty of MDF to do this and it's easy to cut and shape. All connections will be mounted to the "base" so that the thick top plate is clean all around. I haven't decided how much movement/play that I will give the arm board. I need to give myself some adjustability vertically as well as laterally. Will see how this works out.

Idler arm
Air hose damping is installed. This weekend, I will install an axle upgrade from Werner, on Norbert's beautiful idler wheel..

Stacked Platters
What do you guys polish with? Dursol? Mother's Aluminum polish? I am stacking platters and have a SRM Tech platter damping ring.

Mat
Once again, Carl is the man!! I have a L75 mat with center disc ready to go.

Isolation Feet
I have a beautiful set of isolation feet from our very own Carl. I'm excited about these. My wife is not into audio and when she saw them, she was like "wow, those are nice!"


I have started a new thread that specifically talks about my decision to build a Lenco table, along with my impressions and overall rating. You can find it here: https://www.lencoheaven.net/forum/index.php?topic=32968.msg415564#msg415564

I will copy/paste the impressions at the end of this thread, on page 27.

[kenwood61]

Here is a photo gallery of the current state of my turntable, along with L70 motor, and Rega RB202 tonearm. Images are organized in separate posts.

Overall view of top plate, above and below.

[kenwood61]

Closeup images above and below.

My GL75 with the OE motor (50Hz) that I will service and keep.







I have seen longer threaded rod on other tables. Is there a standard rod everyone uses? If so, what is the sizing? I don't reuse the rubber isolation sleeves do I? I'm guessing not.



Platter is in decent shape. Should polish up nicely.

[kenwood61]

L70 motor ... has not been serviced yet.





The motor came with a big honkin' cap, so I plan to use a smaller one Bill gave me.

[kenwood61]

Rega RB202 tonearm showing measurements to get 222mm distance and taped top plate to show possible cutout.

You can tell me if I'm measuring wrong, but I think I'm ok.

Measuring ...



measure on level plane ...



Get right angle with ruler for 222mm length ...







I can fit a piece of wood, matching my plinth material and profile it to fit under the top plate. I can use my cutout piece of top plate to use as a template to rough cut a "shim" that I will profile so there is no air gap between cut plate and plinth. This piece will be part of the plinth, and I can machine two mounting hole to get that part of the top plate fit tight ... or if possible to tack weld a threaded boss underneath to screw from below? Hmm.

Since my armboard will need to be recessed below the top of the plinth ... this I will need to fit the curved shim piece before I mill out the large arm board hole. If I do it right, I will have room to adjust VTA on the arm board. I just have to decide what distance I want.



Here's the tonearm loose fit in existing hole. It's just for looks now.







I'm not digging the plastic 3-point mount ... but if I use this arm, I may source out some metal sleeve or mill my own wood sleeves to match the wood I use in the arm board ... it's vain, but if I can hide the fact it is a plastic mounting, at least on those posts, maybe I'll like it better?

[Andr039]

Hi Matt,
My own built was partly inspired by Artisan. However I did not rotate the top plate, don't remember why 
If you are interested, you my find it here: http://www.lencoheaven.net/forum/index.php?topic=15227.255
Best,

[kenwood61]

Very nice. I really like the plinth, and I feel myself slipping in that direction ... I will look at your build in more depth. I really want to see what you chose for materials. I like the exact size, height, shape ...

[Wout]

Nice & early GL75, Matt. 
Did it have a plastic idler wheel?

[kenwood61]

I still have the plastic idler wheel. Assuming I will just sell that off since I am not restoring the table.

I do like how clean it is, which is one reason I haven't completely given up the idea of keeping the top plate and power switch. But if I do that, it almost stands to reason to sell/trade the Rega tonearm to get an equally nice tonearm that is a direct fit.

[Berndizzle440]

Matt im excited to see how this turns out! Love the detailed beginning and the way youre going through with it! Keep it up -Bernie

[Greg N]

Hi Matt,
My own built was partly inspired by Artisan. However I did not rotate the top plate, don't remember why 
If you are interested, you my find it here: http://www.lencoheaven.net/forum/index.php?topic=15227.255
Best,

Hi Matt,

Thanks for the photos & I am looking forward to your build. I too am struggling with the idea of cutting the top plate of my lovely L75 
You will enjoy Andrey's build thread, no doubt! 

 

[kenwood61]

Hey Greg, I hear you. Looking at it this morning, it has a handsome look with the slate grey and brushed aluminum. Very Swiss looking indeed. I think if it were in pristine condition, I'd consider restoring with a period correct non-Lenco arm, but for the time and money I will need to put into this, I think modifying is the way to go. If I do the frying pan version, I am thinking about trimming the name plate to mount on the back of the plinth with power switch ... or maybe be unorthodox and place carefully on the front of the plinth. I have some design ideas for that I will work out and post for comments. I'm beginning to think I will work out what the end product will be in case that changes some of the choices I need to make. I welcome thoughts and critiques in an effort to make this fun for more than myself.

Here's the area I'm thinking of cutting out for the power strip plate. This allows me to keep some heritage with the deck. Notice I plan to keep the radius of the lower right corner. So the other corners will exactly match. Not close, but it will be exact, so it looks like a Lenco factory prototype they might have done for a future fair event ...



It is possible that I trim to the inside left of the red line so that the badge doesn't have the red line or "on" and "off" text ... which allows the power switch to be out back, and the badge tastefully placed on the front.

[kenwood61]

Another design idea I am thinking about for the plinth involves use inlay/binding material used on mandolins. I used to have a very nice mandolin made by Austin Clark of Clark Mandolins. Thinking of a turntable as a musical instrument, I am surprised I have never seen inlay used. It's origin started to hide the edge of two sides for a clean look, while also adding some decoration. I can easily see using it in the same way around the top edge, or position a perimeter line around the plinth that allows for a duotone effect with inlay creating a simple way to separate the two colors. Even if the tones are very similar, that could be a tasty look. I'm starting to find inspiration in creating something I will love, but that will be unique in the Lenco world.

Here's a pic of the mandolin I used to own, that Austin made for me. Then you can tell me if you feel there is merit in something similar, using an inlay.

[Andr039]

The mandolin looks fantastic! 
Thank you for your kind words about my build, Matt.
You should look through the Lenco Gallery, it will give you some more ideas and probably help to choose the direction to move further.
will keep an eye on your adventure 
best,

[kenwood61]

Thanks Andrey!

I wonder if tonal woods like Spruce, used for mandolins, would create a problem for the sides of a plinth. With a 1/8" thick veneer, I'm thinking it wouldn't create any issue ... then perhaps a dark espresso colored top plate wood like cocobolo, wenge .... and use a cream inlay to separate the two.

But I'll look through the gallery. I have only scratched the surface with the few pages I have looked through. Off I go to get some real work done today, and back at this tonight.