On 12/11/2012 2:08 PM, Han wrote:
....

My jointer is a 6" Delta Shopmaster model JT160. The instructions say
nothing about my problem. I am rather sure it's my technique that did
this. I have to get the thing in a better place and practice with some
disposable wood. OTOH, one of the jigs that Karl (Swingman) mentioned
may do the trick too.

....

OK, I wasn't familiar w/ it--that is a benchtop model.

I did some searching and found several reviews and downloaded the
manual. About half the reviews said they had trouble w/ the beds either
not being coplanar or at least one or the other not flat/straight. That
would certainly cause problems; the longer the work, the more evident a
problem.

One mentioned his outfeed table sagged and he was able to shim it--it
looks to me from the picture on the cover of the manual that there are
four mounting screws for the tables--I'd expect one could manage to fix
a coplanar problem by judicious diddling thereat--if the tables aren't
actually flat, however, there's nothing to be done but have them surface
ground or get warranty service to repair the problem (as one review I
saw said a local service center did for his).

All in all, I'm sorry to say, it looks like a marginal machine but one
would hope one could manage to tune one up...

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