It is just a passive linear tonearm. It really is so simple that it almost doesn't need instructions. The carrier is just two pieces of aluminium angle with the arm bolted to them. The main angle piece is screwed to a bit of wood which, in turn, is fitted to an angle piece with a slot in it to give some vertical adjustment. The only bits that matter are the bearings which need all the lubrication removed. I got them from eBay in the UK and they were £1.99 for ten - so I do have enough for four more!! Plus it has to be dead level or maybe a slight slope inwards.
A support for the wire can by built on the main rail and an arm lift could just be a bar along the back which presses down on the back of the tonearm.
I am a retired gentleman of leisure so really don't want to get into building stuff to sell and in any case, I am the proverbial grasshopper and hate doing more than one of anything.
If you really need some I could do a drawing with dimensions. Not tonight though as it's my bed time over here in France🙂
Gus, here is one I'm working on....kinda the same idea.
Wow, that looks interesting. Does it really just run on a couple of balls? Should be very free running. My only problem with this sort of design is that it seems that the bass can be a bit 'loose'. The joy of the spider like arm in a previous post is that it is rigid in all directions as well as very free moving. The bass has such depth and clarity that it makes this one sound a bit anaemic in comparison. If I hadn't heard the other one, I would have thought this one was terrific though.
PDRCanada,
What is the story on your current tonearm? Is this tonearm better than your glass tonearm?
What is the story on your current tonearm? Is this tonearm better than your glass tonearm?
This one hasnt been test driven yet, but I built another that fit a
P3 to satisfy myself that they work. Its in Vietnam now, a gift to
a fellow enthusiast. That one still used the borosilicate tubes.
Heres a pic......
The new arm uses borosilicate rods as bottom rails instead of tubes, they
nest in the aluminum angle. There is a small, 2-3mm gap between the rods, this keeps the ball bearings in place better than if they were touching, t rides deeper.The top rails are carbon fibre tubes, also with a small gap between.
I liked my old arm with the roller bearings, but I just couldnt get quality bearings local. I was going to purchase from the net when I saw....here on DIY....the ball bearing riding the rods set up. I tried a mock up and was amazed how well it worked........so I guess this is evolution of that old arm.
I'll post here when I finally get this arm mounted on an SP-15 with stacked slate plinth I'm working on.
Cheers,
Perry
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Hello gus 3049
It is not my intention to be disrespectful, but I think the tone arm has 14 bearings. Ask your brother-in-law in England. The reason, I think that it has 14 bearings is as follows: If you look at the cube-shaped ends of the various links, you will notice a bearing mounted flush on each side of the cube. you have to look at both photographs to come to that conclusion. Of course there is the possibility that there is only one bearing in each joint but it would have to be an unusually long bearing which I have never seen. Also, using a single bearing in each joint, would make the tone arm very sloppy and loose.
I'd like to find out, one way or the other.
Sincerely,
Ralf
It is not my intention to be disrespectful, but I think the tone arm has 14 bearings. Ask your brother-in-law in England. The reason, I think that it has 14 bearings is as follows: If you look at the cube-shaped ends of the various links, you will notice a bearing mounted flush on each side of the cube. you have to look at both photographs to come to that conclusion. Of course there is the possibility that there is only one bearing in each joint but it would have to be an unusually long bearing which I have never seen. Also, using a single bearing in each joint, would make the tone arm very sloppy and loose.
I'd like to find out, one way or the other.
Sincerely,
Ralf
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Ah..... I assumed😀
Just double checked and it is twelve but will be fourteen when the arm gets some. As you say, there are two on each joint and it is anything but sloppy. I am no engineer but Bob knows exactly what he is doing. He used to work for Metal Box designing their machinery and they kept him as a consultant after he 'retired'. He is now 86 and still races go-karts and rebuilds classic motor bikes and rides them too.
I hope I still have his enthusiasm if I reach that age.
gus 3049,
Back to the arm in post #9. Working sculpture. What a great concept and realization.
Re Ralf's question about bearings: Did your brother-in-law pre-load the bearings?
Back to the arm in post #9. Working sculpture. What a great concept and realization.
Re Ralf's question about bearings: Did your brother-in-law pre-load the bearings?
What a remarkably good question. To which I have no answer. If I knew what you meant, I would ask him🙄
We are still developing the idea and I do agree that it looks great, much more interesting than the usual sort. Bob has now built in an adjuster for the slope and has found that a couple of the bearings were slightly hesitant and so is going to replace them although it didn't appear to affect the performance. As soon as I get it back, I'm going to try and develop a suitable arm lift. Not too easy with this design but it is needed to make it practical I think.
I am still keen to try it all turned 45 degrees. No scientific thinking behind it, just that it feels right. That was how the idea developed in the first place so I tend to trust instinct here. I like the idea of the pulley and weight through the centre as a means of balance too. The arm lift will be easier to do as well.
Ronnie (my wife) is pleased the arm is in the UK as it means I get to work on the house🙁
"If I knew what you meant, I would ask him."
Try this.
http://www.nskamericas.com/cps/rde/xbcr/na_en/Preload.pdf
The 45 degree arrangement would be striking. Good luck with that.
Try this.
http://www.nskamericas.com/cps/rde/xbcr/na_en/Preload.pdf
The 45 degree arrangement would be striking. Good luck with that.
Aha, I understand now. Knowing him, the answer is probably yes as he understands the necessity of not creating noise in the mechanism.
Next time we talk I will ask him.
Problem with the linear tracker is solved🙂
Out of the twelve bearings, just one was a fraction sticky, maybe a bit of dust or swarf. Anyway, they are all good now and we have some built in adjustment for the slope although I suspect, now that the bearing is done, it won't need any and will track dead level it is so free moving. It felt perfectly free before but then the resistance to the hand and to the groove are obviously two different things.
It is on its way back from the UK and I'm looking forward to hearing it again. Just need to tidy up the wiring and I'm just going to listen to music for a while.
Then think about the arm lift and perhaps build the 45% model just for fun.
This retirement stuff is hard work🙂
Out of the twelve bearings, just one was a fraction sticky, maybe a bit of dust or swarf. Anyway, they are all good now and we have some built in adjustment for the slope although I suspect, now that the bearing is done, it won't need any and will track dead level it is so free moving. It felt perfectly free before but then the resistance to the hand and to the groove are obviously two different things.
It is on its way back from the UK and I'm looking forward to hearing it again. Just need to tidy up the wiring and I'm just going to listen to music for a while.
Then think about the arm lift and perhaps build the 45% model just for fun.
This retirement stuff is hard work🙂
The linear tracker has arrived back from the UK, complete with slope adjuster. Very simple thing, just turn the screw and the whole arm goes up and down at the arm end by a surprising amount. I'm using it with about 1 degree of slope and it tracks perfectly.
Whatever he did to the bearings has worked wonders. No hesitation, rock solid imaging and very insightful, tonally accurate sound. Very pleased indeed.
He did say that if anyone wants one they will "have to bloody make it themselves"🙂
I have to make a decent arm and sort out the wiring and that is it for now. I want to listen to it. I'll think about an arm lift later.
PS. Flickr seem to have done something.....I can't get the right HMTL code to post, just keep getting a thumbnail down!
Whatever he did to the bearings has worked wonders. No hesitation, rock solid imaging and very insightful, tonally accurate sound. Very pleased indeed.
He did say that if anyone wants one they will "have to bloody make it themselves"🙂
I have to make a decent arm and sort out the wiring and that is it for now. I want to listen to it. I'll think about an arm lift later.
PS. Flickr seem to have done something.....I can't get the right HMTL code to post, just keep getting a thumbnail down!
Attachments
and the ultimate DIY turntable
😀
Just for a laugh and as a proof of concept, a rim drive using the platter, bearing and idler from an old Dual and a 12 volt motor from an old tape deck. The speed controller is a chinese horror but it does at least provide some control and once it settles, keeps quite a steady speed.
It shows how the DIY arms are doing as the Origin Live modded Rega RB250 is now relegated to test purposes😱
It sounds good enough to explore further and has the same sort of drive and solidity as the Dual 1019 which I like very much although that too has been shown a clean pair of heels by the new linear tracker on the Origin Live based TT.
Just need to find a good motor and speed controller for €2 and we are there🙂
😀
Just for a laugh and as a proof of concept, a rim drive using the platter, bearing and idler from an old Dual and a 12 volt motor from an old tape deck. The speed controller is a chinese horror but it does at least provide some control and once it settles, keeps quite a steady speed.
It shows how the DIY arms are doing as the Origin Live modded Rega RB250 is now relegated to test purposes😱
It sounds good enough to explore further and has the same sort of drive and solidity as the Dual 1019 which I like very much although that too has been shown a clean pair of heels by the new linear tracker on the Origin Live based TT.
Just need to find a good motor and speed controller for €2 and we are there🙂
Attachments
Hi Gus
I'm interested in the linear arm with the v-bearings. I've looked on Ebay and there appear to be quite a few suppliers. Can you remember who you bought them off?
Thanks in advance
Chris
I'm interested in the linear arm with the v-bearings. I've looked on Ebay and there appear to be quite a few suppliers. Can you remember who you bought them off?
Thanks in advance
Chris
Here you go.
10Pcs Ball Bearings 624VV V Groove Sealed Vgroove 4 X 13 X 6mm 1.7mm Model | eBay
Arrived to France very quickly so UK should be no problem. This is the simplest way of doing it I have seen. As I said, it took half and hour complete. My only reservation about any of this sort of arm is that, as it just rests on the track, it does demount a bit easily. Probably because I'm ham fisted🙁 Sounds good though.
This linear tracker is just the dog's dangly bits. I've been listening all morning instead of doing some antiques repair work which is what I should have been doing - retired hah!
The absolute killer track for most arms is 'Willow weep for me' on Ron Carter's 'Yellow and Green' LP. Its double tracked bass guitar and on most, it sounds OK but not quite real. This arm has it absolutely solid with every nuance and slide clearly laid out in a rock solid image. I close my eyes and there are two of him playing just for me.
I lurve this thing. All the other arms are being removed from the TT and relegated to test or back up duties.
The absolute killer track for most arms is 'Willow weep for me' on Ron Carter's 'Yellow and Green' LP. Its double tracked bass guitar and on most, it sounds OK but not quite real. This arm has it absolutely solid with every nuance and slide clearly laid out in a rock solid image. I close my eyes and there are two of him playing just for me.
I lurve this thing. All the other arms are being removed from the TT and relegated to test or back up duties.
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