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You might want to check out the Shark Forum for some information on the problems they have had with the aluminum bed. With the extended bed the problems might be even worse. I'm not sure how they are modifying the machine for you but I know the shorter bed has given a lot of people trouble. Clamping across the sections of the bed causes the workpiece to be pushed down and makes it hard to keep things level.
I do have an original Shark Pro with the MDF bed and did not have a problem with clamping and love how it cuts. I also have a Shark HD 1 with the aluminum bed and have added aluminum angles under the bed to tie it all together, it helps but you still get a little deflection. The gantry on both of my machines was carved deeply with NEXTWAVE AUTOMATION and the name of the unit. This does not seem to be a problem on the Shark Pro but on the HD 1 using the heavier router there is deflection and vibration in the back of the gantry. They have stop carving the gantry and this does help to a certain extent. I also added adjustable bearing to the HD 1 which also helped.
Nextwave is coming out with a software add on for the controller that will allow you to zero on the 4 corners of the project after you have it clamped to you bed and it will adjust your toolpaths for any variations in level it finds. Of course you never know when they will release it for use (it will be an added cost), the 4th axis they promised over 3 years ago has still not been released (Shark users however are already using the 4th axis and there is documentation on the net if you want to turn spindles).
There are a few other machines coming out that you might search and consider before you make a final decision.
The most important thing to do is put the machine on a sturdy stand and level it before you hit the GO button.
Work Safe, Have Fun, Cut Some Wood,
Your BRAIN Is The Most Important Power Tool In Your Shop. Turn It On Before You Turn On Any Other Power Tool.
A Disability Is Only A Disability If You Let It Be One
Last edited by MEBCWD; 07-31-2013 at 10:54 PM.