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When testing the operation of my Craftsman 4-1/8" jointer/planer
(model #21789), I noticed immediately that the cut along the length
of a board resulted in a curved edge rather than a perfectly straight
edge. I had already verified that the in-feed and out-feed table
surfaces were parallel by laying a steel straight edge along them,
and I knew I was feeding the wood properly. The only way to get
a straight, even cut was to press down really hard on the wood as
it passed over the cutter head - a really dangerous practice since
a slip could cause my hand to fall into the cutters. What was happening
didn't make sense because theoretically the cutter head removes
material at a thickness equal to the difference between the in-feed
and out-feed table heights (see drawing below).
Planed thickness should exactly equal difference
between in-feed and out-feed table heights.
Laying a straight edge on the out-feed table and rotating the
cutter head to position one of the blades at its highest point showed
that my Craftsman jointer/planer came from the factory with the
cutter head a little below the out-feed table height. That fully
explained the behavior. Since the blade was not removing enough
material, the output and input sides of the wood were not riding
parallel to the tables. The solution was to adjust the out-feed
table height to be slightly below the height of the cutter head
blades, as shown in the photo below.
Craftsman 4-1/8" Jointer/Planer Cutter Blade Height Adjustment
(that is a very rare Moore and Moore 18"
steel ruler in the photo)
The cutter head is fixed in height relative to the out-feed table,
so it was necessary to remove the out-feed table to lower it; the
height of the in-feed table has no effect on this phenomenon. I
removed the three hold-down bolts from the in-feed table, removed
it, and discovered a metal shim under each of the three support
points. Hoping they were the cause, I removed them and reinstalled
the out-feed table (see photo below). Amazingly, it was still
slightly too high. It was clearly necessary to remove material from
the support points. Fortunately, the metal chassis casting is made
of a fairly soft alloy so a metal file easily removed enough material
to move the out-feed table down to the point where the cutter head
blades were about a paper thickness higher than the table (see photo
above). If too much material is removed, you can easily add some
shim thickness back.
Craftsman 4-1/8" Jointer/Planer Out-feed Support
Adjustment
In fact, after the first attempt at setting the out-feed table
height, I discovered that the wood was getting a 'sniped' area at
the very end. The cause was that now the cutter head was a little
too much higher than the out-feed table because I removed too much
metal from the supports (see drawing below). The factory shims were
too thick, so I ended up using three layers of metal foil duct tape
under the table support closest to the cutter head to get it right.
Now I am getting absolutely perfect planing action. The entire process
took about half an hour - time well spent!
Sniping of wood occurs when cutter head is higher
than out-feed table.
I have to admit that as much as I like Craftsman tools, there have
been an increasing number of issues with them as received from the
factory. Internet forums are full of examples if you do a search.
Yes, all brands have problems, but over four decades of woodworking
and metal working I have owned many, many Craftsman hand tools (powered
and unpowered) and shop tools (radial arm saw, table saw, lathe,
band saw, drill press, belt/disc sander, jointer/planer, jig saw,
grinder, etc.) and it seems to me the quality is ebbing. Maybe it
is due to everything being built by Chinese slave labor where the
concept of quality is not a cultural thing. Most workers there cannot
afford to own and use the tools they build, so there is no accumulated
experience of what does and does not make for a quality, dependable
tool.
March 5, 2016 Update:
Upon further use of the jointer, I noticed that the input and
output feed table surfaces were not in exactly in the same plane,
causing the work piece to not be square even when the vertical fence
was squared with the output feed table surface. A visual check showed
that the output feed table was parallel to the cutter blades, so
the input feed table needed adjustment. Fortunately, Craftsman provides
a means to make it.
Craftsman 4-1/8" Jointer-Planer Input Feed Table
Adjustment
When you remove the input feed table, you will see that two of
the three table support points are are threaded and adjustable.
Set screws lock them in place. All that was needed was to turn them
until the input table surface was parallel to the output table surface
and then tighten the lock screws. Make sure while doing this that
the correct input/output feed table alignment per the above original
information is retained.
Other Woodworking Tips & Projects:
Posted January 3, 2016
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