DIY Air bearing tangent tone arm
I am thinking about building an Air bearing tangent tonearm. Apart from several commercial versions there don't appear to be many DIY versions.
I have found Trans-fi's evolution and terminator series which appear to have developed from Poul Ladegaards diy versions. They appear relatively straight forward and from images on the web it should not be to hard to reverse engineer.
Are there any other options out there?
Has anyone built Poul's version and can offer me some handy pointers? Do and don't etc.
I have built both versions.
My advice is build a 'terminator' style arm if your going to build one.
No harder and much better results.
just read poul's site, look at vics pics and have a go :)
Main advice is.
The manifold and the carrier need to match perfectly.
Dont use 2 pieces of the same angle as internal and external angles will be different.
When shopping for angle go through them all untill you find 2 bits that match the best, as perfectly as possible. Make the manifold from one piece and the carrier from the other.
Before you drill holes, lap the 2 pieces of angle together. Put a mild abrasive between the 2 pieces of angle and rub them together.
Toothpaste will do fine :)
When making the holes for the manifold, dont drill right through, use tape and punch the 0.3mm holes.
Drill most of the way through the angle and drill the 0.3mm holes.
You will need a small pin chuck twist drill and be carefull! 0.3mm drill bits snap easy! I got 7-8 holes out of each drill bit.
Thats about it. I use a hard walled smoothing tank, seems to work better.
With the terminator style arm, make the arm tube really short.
Get the pivot point in the middle of the arm tube, seems to work better.
I lashed mine together in a day. I always planned to re-build a nice neat version but it sounds so good i havent bothered yet.
Be prepared to say goodby to 'normal' pivoted arms, these are MUCH better imo!!
Do you have link to vic's pictures?
Graeme, is the Terminator a version/iteration of the Ladegaard arm?
Yes, upside down with a short arm.
he has a website for his sales, http://www.trans-fi.com/terminatortonearm.htm
A friend of mine has one, i met him after i built mine.
Vics ones he sells are very good, well made too.
All depends how much you like DIY.
Does Vic have a website?
In the post above.
My experience with "terminator" style arm is just opposite to your's. It has a major drawback: very poor stability lengthwise. It rocks easily back and forth on its slider when touched with finger, since it has immence torque moment for applied force, hanging way below " lift force" application point. I heard "elephant steps behind the scene" - very low fq artefacts on record amplitude peaks, when sylus drag varies significantly and probably causes arm rocking and even touching rail.
Good thing about this design is lower arm mass due to shorter arm: I had 100 gramm arm+slider mass vs. 130 gramm for conventional design. I tend to attribute slightly better details retrieval I heard to it. On the other hand, short arm is more suscetible to VTA/VTF changes on warped records. And lastly bare alu angle rail hanging above record looks not exactly good aestetically and makes records change inconvinient and sometines dangerous for the record.
So in the end I abandoned "terminator" and went back to conventional Ladegaard.
What exactly do you mean by rocks back and forwards? Do you mean the slider rocks on the manifold?
If so, thats either too much air, or the slider is not perfectly matched to the manifold.
I find the VTF is much more stable, VTA will change more but none of my records are badly warped enough for this to matter.
Ive had no isses with it being in the way to change records, i guess it depends how high the manifold is.
personaly, i like the slightly 'industrial' look :)
It rocks like a pendulum around lateral axe when force is applied along the arm. Just press with your finger on the cart body front face and see yor arm moving backward. Normal Ladegaard is not.
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