Uncle Ants
I'm a Shop Keeper
Oh oh oh. That would be a very good thing to have. PM me a suggestion and I shall make it so.
PS. Do you think this PFMer would give me a quote?
Lenco L70 project
- Thread starter Tony L
- Start date
Oh oh oh. That would be a very good thing to have. PM me a suggestion and I shall make it so.
PS. Do you think this PFMer would give me a quote?
Uncle Ants
I'm a Shop Keeper
£23.50 got me A Goldring Lenco GL75 which arrived Friday built into a Dynatron Music Centre:
Just quickly, Friday night, I ripped out the Dynatron amp, removed the transit screws, checked the motor was hanging freely, checked it was running at the correct speed, kept the plinth for now, fitted a spare Pro-Ject arm I had knocking about and fired it up.
This is what came out ... I suspect Dynatron gear must have been quite pricey at the time as it's very well put together - it also dates it to March 1972 - so 37 years old:
.
and this is what was left:
The original arm was completely shot - bent, knackered v blocks, serious rear end droop and basically good for nothing much. The Pro-Ject arm is near as damn it a drop in replacement. The mounting hole is a couple of mm larger than needed, but a ring of copper strip (my missus uses it to keep slugs off her pot plants) in the inside of the mount, and a bit of insulation tape on the column and it fits very snuggly. Geometry is spot on and with the Pro-Ject arm lift removed will go low enough for VTA to be spot on, utilising the original arm lift/lower mechanism. It will even go low enough to just use the standard mat and no spacers, but the counterweight rides a little low at the back. Not enough to affect play, but enough to touch the top plate if you lift the headshell end a little too far when cueing, so I added an achromat and raised the VTA 5mm. The antiskate loop is stuck to the plinth with insulating tape, and I refashioned an arm holder from the plastic arm holding piece on the Pro-Ject arm holder (it just pulls off) and an Allen key. So a bit of a lash up, but it works.
Initial impressions were of considerable bass extension, very good detail retrieval and a natural relaxed sound, but with a lot of get up and go. There was a fair bit of motor noise breaking through though.
Saturday. I stripped and relubed the bearing and stripped, relubed and rebuilt the motor.
There is some controversy about whether the bearing should be greased or oiled. The fact that the bearing cover is not watertight (as I discovered when I flushed it out and got IPA all over myself) suggests grease, however it also uses sintered bronze bushings further up the bearing, with a felt washer for soaking in oil at the top suggests oil. So I used both, grease at the bottom of the shaft where the ball is and a little oil on the bushings and the washer.
I also cleaned the underside of the platter and the idler (it came with one of the metal ones) with some alcohol, and oiled the ilder wheel bearing. And fired it up again. To be honest the motor noise didn't seem any less and the sound was harsh and bright. Touching the motor it vibrates noticably. I left it running overnight ... to a complete change ... the motor vibration has almost completely gone - and so has the harshness and the motor noise. The motor having been rebuilt seemed to need some bedding in. Just to be sure it wasn't a warming up thing, I left it a while to cool back down (it does get quite warm) and fired it up again, and it was fine, the vibrations much reduced. It definitely needed some bedding in.
I spent the rest of the day just playing records. This is an excellent deck. The thing that strikes you immediately next to the Spacedeck is the depth and speed of bass, but then you start noticing that there is a lot of textural detail that seemed missing before, and not just in the bass. Also the timing, speed stability and soundstaging is excellent. I'm a little shocked to be honest and this is on the thinnish original mounting board.
It'll be interesting to hear what happens with a proper plinth.
Oh and the platter was grey, pitted and old looking. Some brasso wadding and elbow grease sorted that out and the edge is now nice and shiny ... but the downside is a shiny platter is a lot less easy to get a grip on when you need to remove it.
Just quickly, Friday night, I ripped out the Dynatron amp, removed the transit screws, checked the motor was hanging freely, checked it was running at the correct speed, kept the plinth for now, fitted a spare Pro-Ject arm I had knocking about and fired it up.
This is what came out ... I suspect Dynatron gear must have been quite pricey at the time as it's very well put together - it also dates it to March 1972 - so 37 years old:
and this is what was left:
The original arm was completely shot - bent, knackered v blocks, serious rear end droop and basically good for nothing much. The Pro-Ject arm is near as damn it a drop in replacement. The mounting hole is a couple of mm larger than needed, but a ring of copper strip (my missus uses it to keep slugs off her pot plants) in the inside of the mount, and a bit of insulation tape on the column and it fits very snuggly. Geometry is spot on and with the Pro-Ject arm lift removed will go low enough for VTA to be spot on, utilising the original arm lift/lower mechanism. It will even go low enough to just use the standard mat and no spacers, but the counterweight rides a little low at the back. Not enough to affect play, but enough to touch the top plate if you lift the headshell end a little too far when cueing, so I added an achromat and raised the VTA 5mm. The antiskate loop is stuck to the plinth with insulating tape, and I refashioned an arm holder from the plastic arm holding piece on the Pro-Ject arm holder (it just pulls off) and an Allen key. So a bit of a lash up, but it works.
Initial impressions were of considerable bass extension, very good detail retrieval and a natural relaxed sound, but with a lot of get up and go. There was a fair bit of motor noise breaking through though.
Saturday. I stripped and relubed the bearing and stripped, relubed and rebuilt the motor.
There is some controversy about whether the bearing should be greased or oiled. The fact that the bearing cover is not watertight (as I discovered when I flushed it out and got IPA all over myself) suggests grease, however it also uses sintered bronze bushings further up the bearing, with a felt washer for soaking in oil at the top suggests oil. So I used both, grease at the bottom of the shaft where the ball is and a little oil on the bushings and the washer.
I also cleaned the underside of the platter and the idler (it came with one of the metal ones) with some alcohol, and oiled the ilder wheel bearing. And fired it up again. To be honest the motor noise didn't seem any less and the sound was harsh and bright. Touching the motor it vibrates noticably. I left it running overnight ... to a complete change ... the motor vibration has almost completely gone - and so has the harshness and the motor noise. The motor having been rebuilt seemed to need some bedding in. Just to be sure it wasn't a warming up thing, I left it a while to cool back down (it does get quite warm) and fired it up again, and it was fine, the vibrations much reduced. It definitely needed some bedding in.
I spent the rest of the day just playing records. This is an excellent deck. The thing that strikes you immediately next to the Spacedeck is the depth and speed of bass, but then you start noticing that there is a lot of textural detail that seemed missing before, and not just in the bass. Also the timing, speed stability and soundstaging is excellent. I'm a little shocked to be honest and this is on the thinnish original mounting board.
It'll be interesting to hear what happens with a proper plinth.
Oh and the platter was grey, pitted and old looking. Some brasso wadding and elbow grease sorted that out and the edge is now nice and shiny ... but the downside is a shiny platter is a lot less easy to get a grip on when you need to remove it.
Tony L
Administrator
The correct answer is both! Dismantle, clean and soak the bearing assembly in a nice 80-90w motor oil to replenish the bushings, heat it if possible. Then assemble wet with lots of oil and use a nice heavy blob of grease liberally smeared across the metal & nylon thrust plate and ball (but keep it well away from the sintered bronze bushings) and replace the circlip. This will seal the base of the bearing. Next force as much of the motor oil as you can through the screw hold on the side of the bearing, a syringe is useful here. Finally replace the screw and soak the felt washer in oil. That's it, job done. If you have done it correctly it will run very smoothly and remain lubricated for years - there should be absolutely no oil collected in the clip-on plastic cup beneath the bearing, i.e. the grease keeps the oil in.
I was given this advice back in 1978 when I bought my first L75, I am certain it is the way they were built. It also works with Garrards, Thorens etc, in fact any deck with a removable thrust plate. It is however important not to get the grease into the sintered bearings as it blocks the pores and stops them functioning correctly - bearings designed for grease, e.g. early 301s, do not have sintered bushings.
Tony.
Uncle Ants
I'm a Shop Keeper
Thanks. The evidence certainly suggests both, but the possibility seems to have eluded those who spend time on the net arguing about it
I had to do all this without taking the thrust plate out, just going in from the top. What tool did you use from removing the spring clip? I had the same problem with the nose bearing of the motor, which didn't get stripped like the back bearing did. I just cleaned the hole and regreased the shaft. It looks like needle nosed pliers - but the holes are a lot smaller than any needle nosed pliers I have. Is there a technique?
Tony L
Administrator
A circlip tool! It's like a pair of pliers but with two round points. Lots available on eBay for a few quid. You can get the clip out with two nails, but you have to find exactly the right combination of swear words and then spend the next three hours trying to find the thing. Just buy the correct tool!
Tony.
Uncle Ants
I'm a Shop Keeper
Uncle Ants
I'm a Shop Keeper
Thanks, I've ordered a pair. Is there any consensus as to what should be used for grease, and also what sort of oil or grease the motor itself should be lubed with? I just used some Teflon grease for bike bearings.
Tony L
Administrator
I used 80W-90 GL4 motor oil and Castrol LM grease. As for the Lenco motor coat the outside of the spherical bronze bushings with grease and oil the centres where the actual spindle runs with the motor oil. A very good hint with largish electric motors like the Lenco's is once you've reassembled it give it a few taps with a wood-handle screwdriver whilst it's running to help centre the bushes, obviously don't hit it hard enough to bend anything, but twatting it a few times tends to make it run a lot quieter. The nose-screw should be adjusted for the right balance of quiet running and minimal play, I did it with the motor balanced on the back of an acoustic guitar to amplify the noise and make what I was doing clearer - expect some fore-aft play, usually a mm or two. You'll never get it perfectly quiet, but quiet enough is good enough - the spring suspension does a good job of absorbing most of the remaining noise. Run the motor out of the deck for a few hours, it will probably end up rather warm, but shouldn't be too hot to touch.
Tony.
Tony.
Uncle Ants
I'm a Shop Keeper
Thanks. I worked out the nose screw thing and had it running on the kitchen table. What I didn't do was the twatting it a few times thing. I suspect a combination of running it overnight and dropping the platter on and off a few times did a similar trick in this respect. The difference between how it was when I left it Saturday evening and how it was Sunday afternoon was literally night and day. It was harsh and bright (and vibrating quite a lot) on Saturday ... and smooth like chocolate yesterday.
Uncle Ants
I'm a Shop Keeper
Serendipity. In terms of fit it's a pretty perfect match. The fact that the lift/lower mechanism can be removed as a piece, so that I could use the built in lift/lower was really handy. The only slight glitch here being that the wire antiskate carrier normally screws to the original base, which of course I have removed. Currently it's stuck to the top plate with insulating tape, but it'll be easy enough to drill a small hole and screw it in.
It's dynamic and absolutely speed stable. Transients are fast when they should be. I have caught my feet tapping in occasion and if this is what makes for PRaT then yes (
). That said the most obvious immediate difference between the Lenco and the Spacedeck is the depth of bass - the Lenco quite obviously goes lower. The next thing I noticed is that you can better hear the texture of bass notes - whether it's an electric bass, a stand up bass, a bass drum or something else - it's less blurred and more convincing in terms of what is being played and how. You then notice the same is true of instruments further up the scale. Big, solid and relaxed, yet fast and detailed and most inmportantly communicative - there's not a lot not to like to be honest. I'll leave it to the theorists to work out why - though I guess it could be down to the arm to some extent (the Space sports an old Spacearm and I'm not entirely convinced any of the things this setup excels at are that arm's forte), I suspect it's mostly down to the deck.
There is still a tiny smidge of motor noise on the unmodulated test record track if you really crank the volume to levels you really wouldn't want - certainly not intrusive or a problem, I can't hear it in practice even at high listening levels. Greasing the speed change slider and damping the idler arm with tape seems to have made an improvement here. I suspect a better plinth (this is basically 8mm of vinyl clad ply screwed into another 8mm of ply) and some judicious damping of the ringy pressed steel top plate will help even more.
Uncle Ants
I'm a Shop Keeper
Plinth sorted, now I just need to organise a respray
