Kapture Group sliding back - play?

[torger]

I've just got a second hand Kapture Group sliding back for an Arca-Swiss system.

On my Linhof I have a Linhof original sliding back, which has felt pads that push the sliding metal piece towards a metal lip, that is the precision depends on "metal against metal", ie very good precision.

On the Kapture Group sliding back I've noted that there's quite some play. The largest play is in up-down direction (rise-fall direction) which I estimate to about 0.2mm. It's a direction that doesn't matter though, but there's also a smaller play forward-backwards in the film plane direction, I'd say it's about 1/20th of a mm (0.05mm / 50um). The Kapture Group does not have felt on one side and metal against metal on the other, but instead fat plastic (nylon?) glide strips on both sides.

Since this is a second hand item I'd like to ask other Kapture Group users if this play is normal and "by design" (it seems so to me), or if it should be tight (and thus this one needs service).

 

[torger]

Oh, as a side note, I've been interested in comparing Maxwell Precision Optics ground glass (on Kapture Groups backs) with Linhof's new bright ground glass. Now I could do that, but unfortunately the only focal length available was 120mm so I couldn't test ground glass brightness (which I suspect is highly similar, with Maxwell a tiny bit brighter on longer focal lengths and Linhof on wide). However I could test resolution, and Linhof's ground glass does have considerably higher resolution.

So considering what I've seen if you're getting a sliding back for a Linhof camera, you should certainly aim for the own brand with the new bright ground glass, despite the extra expense.