Replies

1. 
   Peter36 | Jan 11, 2005 09:16pm | #1

   Join the club. Mine was warped as well by almost 3/16" near the left miter slot. I was afraid of cracking it if I tried to remove all of it at once. I started by loosening the top hold down bolts and let it sit for a week [wasn't building much at the time anyway.] After that I slid in a shim of the correct thickness and let that sit for a while, started using the saw again with the bolts still backed off about a quarter turn. I then started slowly tightening the bolts over about a 2 week period. I don't know if I was wasting a lot of time or being paranoid but I thought better safe than sorry. My top is now flat and everything is good. By the way I used brass shim stock available at machinist's stores, I think Lee Valley sells it too.

1. 
   Paulie | Jan 12, 2005 12:00am | #2

   Just out of curiousity how old is your saw. Mine is about 6 years, and is warped in the same spot. It doesn't seem to be aproblem until I use a tenon jig, which how I discovered the problem.

1. 
   Peter36 | Jan 12, 2005 12:28am | #3

   My saw is probably about 10 years old and oddly enough I noticed it as well when I was getting these odd tenons from my tenoning jig.

2. 
   woodhoarder | Jan 12, 2005 05:12am | #4

   If cranking down on bolts and shims doesn't work, you may want to consider taking the piece to a machine shop and having it decked (ground flat). I had a rockwell jointer fence that was twisted, and it cost me about $20 to have it flattened.

   As for why it happens; Cast Iron needs to "season" after it is cast, this allows the metal to move as it cools. This can take up to a year, depending on the piece. Then it is given its final grinding. Sometimes the iron hasn't finished relaxing when it is ground, and any stresses in the casting are released at weak points in the metal (i.e. miter slots). Usually shimming as was suggested works quite well, depending on the severity of the warp. My delta con saw has a pretty flimsy sheet steel housing, though, and I just can't imagine it would be strong enough to muscle around a 5/8" thick plate of cast iron.

   Woodhoarder

3. 
   DougF | Jan 20, 2005 02:05am | #5

   Paulie,

   Had an old craftsman TS that did the same thing.  I think I caused it by hanging a heavier 2hp motor to replace the old 1hp unit.  The additional suspended weight was more that the design could handle.  Also, a heavy tenoning jig focuses the weight over a small foot print in an inheritantly structurally weak area containg the arbor and trunion which are suspended in the same area as the cut-out for the throat plate and miter slots. 

   If you can install bracing to support the rear table edge, then corrective measures, assuming you can get the top flat again, it may hold up.

   I found that my solution was to sell the TS.

   Doug