1. Is the vertical supports for the coil springs located directly underneath the centre of the spring support base plates?

2. Sometimes if they are CANTILEVERED beyond the centres ...the result will in fact be structural vibration.

3. Sometimes, if the leg does not go directly straight down to the concrete floor....a bad sympathetic vibration will develop.

4. Try doing a REED METER test on the support beams to see how much vibration is being registered .

5. Sometimes if the structure is vibrating badly enough, you can NOT get a decent stroke check on the screen because the support it is on is not QUIET.

We had a screen in Asbestos mine.......with weird vibration problem and hard to identify. We went down on 4 separate trips to troubleshoot. In the end, we went down below the screen and identified a new vertical support beam that had been installed on one corner only underneath the spring support area.

The beam was a titch on the short side and was causing the erratic vibration...a shim was used to rectify this problem.

I do not know if any of above applies to your situation....but, very well could. ■

aujwc

One of the reson just to touch the cards( as mentioned by George) is to see if you can get full stroke and the shape of it.

Ziggy

www.vibfem.com.au ■

Hello Aujwc"

DID you ever find the problem with the vibrating structure??? ■

Was there an actual problem or just checking?

Honestly the stroke check is not perfect, but not real bad either.

The unit looks fairly balanced by those stroke checks.

Looks like .68" (11/16" long) or between 5/8" and 3/4" stroke length.

May be holding the pencil on a little HARD. Just have a nice sharp pencil, hold it as close to right angle to the sideplate as you can and just barely touch it and take immediately off to get a nice clean, thin, readable stroke check line.

If you hold on too long.....you get mutiple strokes over each other and hard to read. ■