mettler M5 analtical balance 0.001 mg scale missing part help

I thought I got a amazing deal on a mettler M5 scale 1uG resolution!, however, a piece is missing...



on the right most side you can see the two pictures of the missing part from a birds eye view, and the other pictures show an in action shot of working scale. Hopefully my crude MS paint drawing the part I am looking for.

Do you think its reasonable to make a spare for this part? How important is the interesting curvature off it, can I drill and tap the holes in the appropriate location without the rounded edges and leave it looking "boxy" while still functional?

I see the perimeter holes seem to form a pretty darn good equilateral triangle, I assume the two holes in the middle are equidistant from the triangles point and base, however, I do not know the offset of the middle holes on the X axis, while I do know their spacing. I assume that they are equidistant from the line drawn in pink...

I dont have a machine shop, but I do have a tap and die set + a decent drill press and a hacksaw, so I feel that I can get some blocky 80% replacement with a few hours of labor.



Also, I don' know the thickness of the peice, but I don't think it matters too much, as the notched sliding flat head screws allow for Z axis adjustment.


also, should a specific grade of steel be used?

or, does anyone know where the hell too get replacement parts for a mettler m5 before I go on this insane quest? I got this hunch without some serious precision machine tools this will end up like shit... but I really want my mettler


does anyone maybe have one of these parts that they can scan for me so I can make a template?


help me make this work



[Edited on 3/6/2015 by mettlerfixer]

[Edited on 3/6/2015 by mettlerfixer]

M5 microbalance

Quote: Originally posted by mettlerfixer

I thought I got a amazing deal on a mettler M5 scale 1uG resolution!, however, a piece is missing... It's been a while since this was posted, I don't know if the topic is still of interest ... I too bought a M5 balance, thinking that if I was lucky, and it wasn't missing anything, or damaged, it would be a bargain. I got lucky, I think, and so far as I can judge it is in good order. As yet I have not managed to clean the internal weights to my satisfaction, so there is some inconsistency in the readings, depending on which weights are in play. If anyone has any suggestions about cleaning stainless steel weights so they are not damaged, bearing in mind they should be good to better than 1µg, I would be grateful. I have been advised that acid or alkali are out, and any rubbing is a no no. What about mild neutral detergent at 60°C? Or silk? any suggestions about removing 50 years of accumulated grime? The piece that you refer to is a very highly engineered part. It has a synthetic sapphire plate which rests on the knife holding the balance pan when the arrestment is removed. This has to be flat, smooth and horizontal, and made from a suitably hard material. It also has another three bearing surfaces on the same side as that, and two on the other side. I think they might be agate, and they make contact with what look like steel pins when the balance is arrested. The two hold the suspension arm holding the pan, and the other three locate it in precisely the same place and orientation above the knife when the balance is arrested. I've made some photos, and if you're still interested I might manage to do better. Not sure what you mean by scans. One other thing is worth mentioning, and that is the anti-static devices that come with some of these balances. Between 1958 and 1966 the M5 came with 6 radium 226 radiation sources. This has legal and health & safety implications. Beware! [Edited on 11-11-2016 by philevedoug] [Edited on 11-11-2016 by philevedoug]