On Feb 21, 6:59*pm, wrote:
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

So, if the bottom wheel is touching the cover, it needs to go back as
does the top wheel. Of course. the guide rollers will need
readjusting after that as well. I would have gotten out the pulley
pullers to remove the bottom wheel, cleaned up the no doubt burred-up
shaft, retapped the setscrew hole while it was off and replaced the
setscrew with a decent domestic-made one. I've never seen SAE
hardware on any of the asian 4x6s, it's no doubt one flavor of an 8mm
hole. There are several pitches to choose from, it'll be the one that
no one in town has, I speak from experience here.

Stan