Trans-Fi Terminator Tonearm: 2019 Update

@qwin Have you found the source of your problem? It’s a very weird condition. I have never had a suction problem as you described. 

@qwin

Here are a few tips for your air supply -

For surge tank Bruce ( ET ) recommends loose cotton stuffing - I would use upholstery wadding.

The surge tank should be closer to the pump and far away from the arm.

A long line of air hose ( 10ft or 3m ) to the arm will further smooth the air flow.

I also found that with small air pumps using an isolation transformer ( large ) made a significant improvement in sound quality.

when I come to move the wand back at the end of a record, the slider has great resistance,

I feel sorry for your cartridge suspension. It's probably not going to last very long.

Perhaps you should try cleaning out the capilliaries. You should also regularly clean the bearing surfaces with alcohol to make sure they are clean.

@dover I cleaned the manifold and checked each hole was clear, fairly early on.
It only sucked down at the beginning or end of an album, after I had manually moved the slider a reasonable distance and even then it was an intermittent fault.

As mentioned above, in my 3L pre tank, I have changed the filter material to half filled with 11mm ceramic beads, with 6mm BB gun plastic pellets on top. This seems to reduce pulsing a lot.

I don't like the idea of using cotton stuffing as this will have loose fibres that will need a very fine filter to prevent them getting through to the manifold and potentially blocking its fine holes.

Since using the new filter material, the slider has not stuck once, which is strange.
All working well and sounding great at present, the only thing I might try is a longer air tube from tank to Terminator. I have the Pump 5 inches (125mm) from the Tank as in the picture above. This allows me to unplug the figure 8 lead from the pump and the single 4mm outlet tube from the tank and move the whole set up as one. Handy for transporting to HiFi meetings.

@qwin i had used filter materials in the smoothing tanks before, a combination of cotton ball and crippled paper strips. And the pressure from the pump had to be increased by quite a bit to allow the arm to float. Was there a need to change the pressure level by changing filter materials? This shouldn’t be the cause of the suction problem, but I was just curious.

Btw, I had to change my username due to verification a problem with my last username. 

The sucking down of the slider problem, was there even with an empty 5L tank. I tried two empty 5L plastic petrol cans and it did it. A couple of years back, I remember someone on Audiokarma had a similar issue, don't think it was ever resolved. It doesn't seem to do it when tracking a record, as I would here distortion and skipping. It's only when I cue at the start, or return at the end of an album.

I had to turn the pump up a tiny amount when adding the beads. The beads offer less resistance than an aquarium air stone for instance, more and larger spacing. I use two 4mm tubes from pump to filter chamber, one 6mm tube from there to main chamber and one 4mm tube from main chamber to Terminator. So stepping down as it goes through to form back pressure in the chambers. The idea is to give the pump something to push against and encourage the air to go down many paths in the beads, rather than the shortest path or line of least resistance.
That was my theory and from a pulsing point of view it seems to work very well.