DIY linear tonearm

Here is the last version of LC, which is on a turntable. It can be any turntable.
Testing has shown that this version sounds better, has more volume and better localization, better works out the unevenness of the plate. In the video, I put a piece of toothpick under the mat and shifted the center.
Three pivot points ensure stable contact with the guides, and the roller provides a secure footing and does not move off center. By changing the height of the roller axis, we easily adjust the VTA. The cart has become lighter, making it easier to roll. Making this option requires the least amount of work on precision equipment. When manufacturing, I buy suitable profiles from which I remove excess metal.
I will definitely use ceramic balls.
The ingenious idea of CARLO to put a parallelogram on a swivel base and install guides on it, allow making the cart with the cartridge as light as possible.


The 4 axis pivoting points is a wonderful idea
Are you open to building one of them for me ? I have a Victor motor/plater setup that I need a arm for. IMG_8513.jpg
 
I have a Victor motor/plater setup that I need a arm for.

Making an LTA that will perform as well as most pivoting arms is not difficult. The original 2 glass rod arm in this thread works extremely well. I built one to test and it out performed my Technics EPA100 and was made mostly from my scrap bin. The only thing I bought was a carbon fibre tube and borosilicate rods.

It's easy to make with hand tools, give it a go.............
 
Radial TA progress

I have continued work on my radial tone arm development that has been posted here before.
I have made some progress that i thought might interest readers. All of it borrows extensively on the experience of other posters, thanks to all.
One of the features is that I make everything without precision tools and so, cut and made by hand and eye, all the various components need to accommodate inaccuracies on occasions.
I am quite content now with the non recirculating ball (ceramic balls on anodised rails) carriage with one primary rail to which the cartridge carrier is fixed and a secondary suspended rail that accommodates any variations between the two rails. This rides v on vee on simple anodised radial rails and is the lowest friction solution i have tried.
That deals with horizontal motion, until something else comes along………..
Vertical movement has seen various developments all derived from the parallelogram motion of the Roberval balance that as it moves vertically both keeps the angle of the mobile end (cartridge) constant and keeps the apparent weight (VTF) constant, all within operational limits of course and provided its properly executed.
I started with this oriented in line with the rails but quickly turned it 90 degrees to be in line with the grooves to remove some potential torque. First pictures show this orientation.
To start with i used a ball bearing motion which worked fine but was partly responsible (rattling balls) along with loose counterweights for a bass grumble excited by the cartridge in the groove.
That has been sent packing by removing any source of such rattles, which was recirculating BB’s and nut and bolt adjusters.
I then used Mylar hinges for several experiments but was always concerned about the lack of stability and decoupling, although they worked quite well, were easy to make and safe and tolerant. They were apparently very flexible but always caused a rise in VTF in warp movements. You can see pictures of some variants.
I then spent some time trying to construct a knife edge bearing parallelogram, which worked eventually on the test rig with magnets retaining the metal knife blades into the grooves. Even though i could turn the whole apparatus upside down without it coming apart i could never convince myself to commit a delicate cartridge to its tender care. Components are shown in the picture.
So i decided to follow the route of pentip pivots, many people have posted about these, just as the other parts above, its great learning from what other people have done.
There is little variation in VTF in the 3mm warp test shown in the two pictures below.
I made this using hot bent Lexan sections and the two sides of the pivot are held in place across the pentips by the spring of the channel section Lexan. It feels rock solid and confidence inspiring to handle. Last picture shows this playing successfully.
It all requires careful jigging but once again was executed by hand.
In retrospect a standard channel section of a similar material performance would allow me to start with consistent dimensions, but i quite like the appearance of the thermo-formed Lexan.
I am sure it could be improved, possibly reduced in size and weight, tighter tolerances etc.
Having played records i know well now for a couple of days I can now say this is the current best result, sound is tighter, open and detailed, more precise as well, just as one would expect with pivots with little play and better coupling.
I hope this is interesting and look forward to lots of interesting input and feedback.
M
 

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Hello, this thread has moved on since I started following. I’m still on a version from page 100 odd. Hopefully someone is still involved who is familiar with that arm.
I’m having tracking issues on albums that have very narrow grooves/a lot of tracks. Skips. On something like “take 5”, three tracks per side it’s fine in terms of skipping. When one looks at the cantilever it’s under stress more than I’d like. I have a terminator air bearing arm as well and that is silky smooth. I’m using open fully ceramic bearings, dry on a very level track. I’m using two 6mm borosilicate rods and maybe they are not as straight as they should be... I thought they were but maybe not. Any advice welcome. I’m about 90% there I think. Just need this last irritation to go away.

Thank you in advance for advice given.
 

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I’m having tracking issues on albums that have very narrow grooves/a lot of tracks. Skips. On something like “take 5”, three tracks per side it’s fine in terms of skipping. When one looks at the cantilever it’s under stress more than I’d like. I have a terminator air bearing arm as well and that is silky smooth. I’m using open fully ceramic bearings, dry on a very level track. I’m using two 6mm borosilicate rods and maybe they are not as straight as they should be... I thought they were but maybe not. Any advice welcome. I’m about 90% there I think. Just need this last irritation to go away.

Thank you in advance for advice given.

Hi JW, i am a recent joiner and started with BB's on rods as well. whilst you can polish the rods, and i suggest that you try that, i listened to advice and moved on to anodised aluminium rails with non recirculating ceramic balls, this had much lower friction and no rattling balls. i also feel your wiring looks "draggy", my first set was as well and that adds to skips and i took a leaf from Niffy on this and use 38-40 awg magnet wire now, all as per his and others advice, two strands per contact twisted, then the 4 sets twisted as well, and suitably dressed this works great, all the abpve you can see in my last summary post above. i have zero skips if i keep it all clean.
Now, about that TT, looks lovely, what is it please and does it perform, i am considering getting a Lenco and fully modding it.
Mike
 
Mike, thanks for the input. Clearly this thread has marched somewhat. I read up to about page 200 odd a couple of years ago and decided during lockdown to give it a go.
I will start reading and see where the latest incarnation has taken people. Yours looks quite amazing and seems a completely different concept from the original thread starter.
Forgive me if I’m wrong but this(my one) is a clearaudio copy..ish. They have done it successfully and I was under the impression many others had but maybe not? It feels like the devil is in the detail. And maybe amateurs struggle t9 have access to the materials required to make this concept work successfully.

The wiring is from an old terminator arm wand, it looks awful I agree. I have ordered some silver wire from Stan in Germany who makes panzerholz cart bodies etc. ..but this maybe too thick. I’ll investigate the magnet wire that sounds like a great idea.

I’ve just spoken to a company that makes quartz glass rods. Apparently borosilicate are thought of as rubbish. The MD called me back and had a chat as he was interested in Hifi. Before I completely give up on this as a bad concept and start something new i feel i need to try a little more first. Maybe try some higher quality rods.

The turntable is a lenco 75. I had an lp12 that was maxed out. It had aluminium plinth, tangerine Audio Stiletto, aluminium base, radikal klimax power supply- about £20,000 if bought new. The changing of the plinth from wood to aluminium was huge. I bought the turntable at university and got sucked into the upgrade path. I knew it was a poor concept and I wanted to find a cheaper deck that performed as well. I bought a lenco and a ptp6. I put it in a multi layer plinth, massive, ply and MDF with a tri-planar uvii arm. The linn sounded better. I then came across a trans-fi salvation with terminator air bearing arm. This easily beat the lp12 so I sold it. I then made the lenco. It has a panzerholz plinth split into 4 to aid isolation fr9m the motor and arm ends. I got it going on Saturday. The trans-fi has a Kondo io cart in it. The lenco a troika. The lenco sounds so much clearer. Everything about the trans fi should be better than the lenco so I put it down t9 the panzerholz. I am now going t9 make a panzerholz plinth for that. A long story but hopefully you may understand how it sounds a little better. The plinth has absolutely been a huge success. It sounded dull and horrible in the massive ply 9ne but super clear and lovely in this one.

I just need to get the arm to function.

Best Jonathan
 
and seems a completely different concept from the original thread starter.
I pinched ideas blatantly from many other people and enjoyed the ride as i developed it and took up some time in lock down! - there are lots of routes and lots of people have made their own work well, i don't think there is a best solution, just different. whatever i do has to be made without machine tools as i don't have them. i liked the ideas of LC where there is really no arm and no torque as the stylus tries to move the cart across the record, but i couldn't see why the vertical motion should move the whole rails assembly so i (foolishly) decided the rails would be radial but stationary and the vertical movement would be taken up by the parallelogram motion, not a pivoted arm, but as i said there are lots of alternatives

Forgive me if I’m wrong but this(my one) is a clearaudio copy..ish. They have done it successfully and I was under the impression many others had but maybe not? It feels like the devil is in the detail. And maybe amateurs struggle t9 have access to the materials required to make this concept work successfully.


Best Jonathan

I don't know the clearaudio but the devil in the detail is absolutely correct, if you can minimise friction in the travel and the drag of those wires i expect you can get something working quickly.

The wiring is from an old terminator arm wand, it looks awful I agree. I have ordered some silver wire from Stan in Germany who makes panzerholz cart bodies etc. ..but this maybe too thick. I’ll investigate the magnet wire that sounds like a great idea.


Best Jonathan

Find the niffy description of magnet wire in this thread, it will transform things

.

Lenco, panzerholz

Best Jonathan

So, all i need to do is find a reasonable Lenco TT to mod, i obviously dont need an arm, where do you buy panzerholz?

Look forward to seeing more of your journey, i have enormous fun with it, mike
 
Thanks mike and warrjon, first on the list is to sort the wiring out. I’ll also look up niffy’s post. .. and the other 200 odd pages I seem to have missed. I knew it was rubbish and it was going to be addressed but it hadn’t occurred to me that it could make that much difference.

Getting panzerholz in the uk is now an issue. I was able to buy some a year or so back and he sold it in 500x500 specifically for audio types like us; but the guy has retired and there is no uk importer now. It’s probably possible to get it from Germany but it’s heavy and they may want to sell big sheets. However there is an equivalent material made by a rival company called permali. Audio note have started using it in there ce players, belt driven no less. I spoke to the guy there this morning and they sell it as a 1mx1m sheet for about £350 I think. I’m waiting on a quote. So it is possible. If you google permali dense wood it comes up.
Bw Jonathan
 
Ordered the magnet wire. What a cheap way to buy tonearm wire and high purity copper apparently. Just as an update. I swapped bearings this morning to some boca bearings from USA. Not the ones niffy suggested but the guy at boca. These are hybrid 5x9x3 and no skips all morning on all records. That might have sorted it. I’ll sort the wiring out as well and that should absolutely help. I also have some same spec fully ceramic ones to try but I have to degrease those. I’m going to order the niffy ones as well so I’m covered all ways round.
The fully ceramic ones I have I have bought from the uk from two different suppliers but I suspect they are from China and a bit crap. Why can’t you get good quality things over here.
Anyhow thanks for the input. Good luck with you TT mike, I look forward to seeing it with your arm. I’ll have a read of the rest of the pages and see what th8s new funky arm is all about.
 
We look forward to hearing your future progress.
Good to learn the skips are gone.
That reinforces my experience, get the friction and drag down.

I am going to try and understand resonance in the arm next and see what might be done for improvement.

Thanks for previous info on Panzerholz, it doesn't fit my ideas as i like that materials should be very inexpensive and adding free labour makes a really good product at a very low cost, to me that is part of the fun.
There is nothing expensive in my TA, to buy absolutely everything would be less than £50 and there's probably enough there for two!😊😊

It looks like i have a Lenco on the way now and will want to modify it the same way, work not cost, so i will start research on that
 
I completely understand your point of view with regards to materials and cost. This arm is the same, extremely cheap. The only expensive bit is the panzerholz and it’s tiny but I use the off cuts from the plinth and I have loads.
With the lenco I did a lot of reading on lenco heaven about other builds and materials in particular. This is an excellent article which might help in choosing materials if you haven’t seen it already.
https://qualia.webs.com/plinthbuilding.htm

My mindset was if you could build a very good deck for almost no money, is it possible to build a massively high performing deck with a relatively modest outlay in comparison with spending £10,000 upwards. As previously stated this is better than the trans fi with the slate plinth, this is a bargain deck in itself. And the trans fi was better than a £20,000 linn lp12, I was trying to find a way to sell the lp12 and free up some money without going back in sound quality. I made a few mistakes along the way with this whilst discovering but it is possible to make this for about:

Ptp6 and bearing €500, lenco £150, panzerholz £150, aluminium and lasercut £150, cnc panzerholz £130, isolation feet with ceramic ball about £120 I think.

That’s about £1200 for everything minus the arm with the best materials you could find. I am extremely happy with it. But the theory behind the trans-fi is better as the motor is more isolated and I feel the terminator is a better arm(probably). So I would expect a huge uptake in performance once I put a panzerholz plinth on it. ...if I can get the stuff.

I realised how much affect a plinth could make when I put the tangerine Audio Stiletto on the lp12. It’s an all aluminium plinth and top plate in one and retails at £5,000. Absolutely huge, and aluminium as you can see from that article is not a particularly good material for plinths. This plinth has been a huge improvement over the ply/ mdf one and clearly better than slate that up until now I always thought was a good material... anecdotal testimonies as opposed to scientific data.

It’s all a journey and fun discovering. If you haven’t discovered it yet lenco heaven is a great resource, there is also a fb group which is extremely good.
Jonathan