On 20 Feb 2012 05:11:58 GMT, "DoN. Nichols"
wrote:

[...]
The only *correct* tension on these machines is as hard as you
can twist the knob by hand -- and perhaps a little more. The tension
knob is too small for the task. :-)
[...]

Thank you all.

To answer some of the points that have been raised:

1) The saw was bought new.
2) I opened, cleaned and re-filled the gear box immediately after
purchase.
3) The back guide bearings do not touch the blade when not cutting.
4) I use it to cut mild steel almost exclusively
5) To get the tension they recommend (actually, the recommendations
differ between manuals!) I use a pipe wrench - with three fingers
only.
6) The tension adjustment and tracking adjustment are interdependent
on this machine. Presumably the frame bends. This happens at quite low
tensions.
7) The wheels were *not* co-planar. The driven wheel was slightly
further back. This is where the fun started:

a) I thought I would remove the driven wheel , inspect and clean the
shaft and reposition it. I had no difficulty removing the set-screw.
b) The wheel was quite tight but with some effort and Liquid Wrench I
was able to get it to move axially about 3/8". When trying to remove
it completely it simply got stuck and would not budge. I tried
rotating it on the shaft and it did so with major effort. I could see
no evidence that a key is involved. Manuals does not show one. I
looked and felt all around the hub and could not see/feel any more set
screw/pins/whatever.
c) I though I would just move the wheel forward as far as it would go
and fix it there with the set-screw and be done but the set-screw
*would not go back *!
d) The manual says this should be a M8 screw. This was clearly wrong,
the screw is 5/16-18. I tried a different 5/16-18 screw to get into
the hole (I thought there may be an alignment problem) and it behaved
the same way - it would turn about two threads and then it would
become difficult to turn.
e) I cleaned the set-screw hole, blew it out with compressor, looked
down with a light, poked about there with a stick to no great benefit.
f) I run a bottoming tap as far as I could but still was not able to
get the screw in far enough to hold the wheel securely.
g) In the end I made a little 1/4" diameter plug, dropped it in the
hole and screwed the set-screw after it. This did the job.
h) The blade now runs much better after I re-adjusted the
tracking/tension. However, the driven wheel is touching the cover.

I left it at this point. I do not pretend to understand any of this. I
shall try cutting something on Thursday...

Michael Koblic,
Campbell River, BC