DIY linear tonearm

[SGregory]

DL103R works quite well in my set-up.

[PDRCanada]

Yeah, I know, not quite in the spirit of this thread. But it was this thread that made me lose all that sleep thinking about this arm...so I thought, why not.

Moray James posted somewhere that two pieces of glass in a "V" shape could
work as well. I just couldnt imagine cutting a piece so thin that the arm would still be able to rock back and forth. I bought 12 pieces of glass tubing, what to do with them?. Then it hit me, ride the ridge....

The prototype weighs in at 20 or so grams...WITH the 6 gm cartridge, and counter weight.

I have to buy a bench drill press so I can bore the holes accurately....
but it seems to work beautifully, so far.

OK, I need you guys to tell me the pitfalls....

[Golana]

I like that alot!

[kffern]

Good thinking PDR.

I would think Bearing width would be more important now but 2 bearings would be better than 4 IMHO.

kffern

[tomatamot]

Originally Posted by kffern

Good thinking PDR.

I would think Bearing width would be more important now but 2 bearings would be better than 4 IMHO.

kffern

But why? It`s still a 4 point contact carrier.


Hans.

[drumdoctor]

But potentially less rolling resistance or "stiction" due to 1/2 the bearings? I like this.

[gaborbela]

Great idea, nice work!
Gabor

[spinning wheel]

Nice work !

potentially less bearing ( rolling ) friction , but bearing edge / glass radius contact barely visible on the foto's . indeed the bearing size ( width ) plays a large role with this concept . well ... in my view .

Nice and light construction !! wondering if those bearing rods can be a bit shorther in order to avoid resonance ?

Paul

[Golana]

[QUOTE=spinning wheel;3702377 wondering if those bearing rods can be a bit shorther in order to avoid resonance ?

Paul[/QUOTE]

My thoughts exactly. I was thinking , smaller glass, 8mm?? and you could go with the 3mm-4mm bearing width.

The only thing I cant wrap my head around is, on the flat glass pane, the one in a "V" version. A known working version. The bearing only rides up on either side. Here it will need to ride not only up but navigate the curve. will it loose momentum up and or back, in the journey.

[PDRCanada]

I think the 11mm tube size with the 3mm bearings work remarkable well.
When slid back and forth on the rail its incredibly stable. I have it balanced right
now, when its dipped it comes back to rest in about 2 "nods". It will be faster
when its not balanced I'm sure.
The arm I'm using was abandoned.....that means I screwed it up,lol....when I was attempting to make a "T" carriage. Its junk and it was just a way to try the
double tube quickly. So its easy to change....like you guys mentioned, I'll make
the bearing rods shorter and raise the wand closer to the tubes. It hangs lower than it should as it was meant to ride higher on top of the tube.

My biggest challenge is to drill holes properly...straight and true...but I've brought home a Dremel drill press tonight, so that shouldnt be a problem anymore.

I have the morning off tomorrow and I'll try and get a new carriage built, and
post a you tube vid of it working. Like I say it glides remarkably well and its very hard to knock it off the rails.

Perry