making a tonearm...

[nerd of nerds]

hello!

I recently got some gemini xl-500 II turntables at a garage sale for 25 bucks for the pair.

One has a busted tone arm and as i type this it is being glued back together with krazy glue...

I am wondering...Could i make a replacement tonearm for this that excedes the performance of the old one?

I have access to a laithe and mill. And i'm pretty sure that if i asked, my shop teacher would help me with it after school sometime...

I'm going to be learning the ins and outs of djing on these and will hopefully one day be good enough to need some technics 1200s...but for now i have these...

Ideas? thoughts?

[karma]

go for it

[nerd of nerds]

What exactly will this endeavor entail?

I'm new to the whole vinyl thing...

How long does the tonearm need to be? is this waaaay too much for a beginner (at best) machinist?

[bobhayes]

If you have two of these turntables, you could copy the tonearm from the other 'good' unit.

The basic requirements are for the sylus to 'track' the groove correctly, which entails exerting the correct amount of downward force on the stylus, to prevent it from leaving the v groove surfaces, and the stylus should always be in line with the groove (hence the geometry of tonearms), especially with eliptical stylii.

There is no reason you should not be able to build a functioning tonearm with the resources you have available, and there's no better sounding equipment than the stuff you made yourself... ask anyone here!
Many more expensive tonearms and ancillary items take mechanical resonances very seriously, but for D.J. turntables, don't worry too much about it.

I think the most important factors are geometry, mass, and making all the bearings as free as possible (using small spindles)

Good luck if you decide to have a go.

[SY]

Search for EC8010's threads on his home-made arm. It's a unipivot and looks like an excellent design.

[Nanook]

Nanook's $2.19 (CDN, $1.70 ish USD) tonearm

so simple and so cheap, but not what I'd call a DJ arm by any stretch..:-)--sorry no photos

EC8010's arm is (if I recall) quite beautiful and simple as well, but still not what I'd suggest for DJ equipment .

Are you planning on using these in home?

[nerd of nerds]

yeah, **** it

I'm gonna just get a replacement tonearm and counterweight from gemini

[Nanook]

hopefully not too expensive...Technics has their arms as seen on the SL1200 series available for $100 or less direct. I'm sure they'd be on par or better than the Gemini one.

[Franz G]

Funny ideas: it is very much "bricolage", but why not, doing first steps in dyi tonearms or TT?

This thread lighted some fire inside my brain...

The last days, I played a lot with different tubes: rolled out of balsa, different diameters. Massive wood, from relatively soft to hard. Aluminium, carbon fibre.

I was searching for a very low resonance for a tonearm about 35cm length. I took the tubes, added 10g lead at one end, fixed the other end and put the whole thing in vibrations.

The best result I got was a relatively big diameter balsa tube.

So, I will play a little bit with wooden unipivots in the next weeks

As a pivot I use a pencil, as I have a very good pencil sharpener.

Franz

P.S.
This article about the Altmann tonearm in the German High-End Journal was indeed prepared as a joke for 1st april: http://www.altmann.haan.de/tonearm/t...hej_1_2002.pdf

[Nanook]

If you do I'd be very interrested. I used very strong (96ksi yield strength), 7509 aluminum. actually 9 mm in diameter, not the 6 as on my drawing. I have no means for weighing it but it is very light. a few grams at most. No internal dampening. With a Grado Sig 8 it sounds very good, besting my SME 309 Magnesium tonearm (same cartridge. Next, carbon fibre...

nanook's $2.19 tonearm