Sag in center of spoil board and significant downward deflection

My spoil board has a decent sag in the center from left to right rails. There is also a significant deflection if you push down on the spoil board.

Has anyone else noticed this and is there any fix for it. I am getting a large section of the cutting areas where I get no cutting action from side to side.

Hi Bonch, is your spoil board made of wood? If yes, maybe soil board is swelling.
For example MDF is very attract to water.

It is the stock spoil board I just received on my new Shapeoko 3XL

I hope to try mine out soon and I’ll let you know if I have any issues as well. I worried about the same thing and figured I would add braces on the bottom of it happened to me.

Hi I also have a simular problem, I just finished building a so3 and during the test run where you install a felt tip pin and printout Shapeoko the middle was to low and the letters didn’t come out. So I put a dial indicator on the carriage and ran it from side to side and the waste board went up and down + and - 10 thousands for a total of 20 thousands. But I noticed also the the indicator was sitting there and I pressed any where on the machine it would move the dial at least 5 thousands one way or the other depending where you press. My kit came with rubber feet and I’m thinking it allows the machine to flex. I sent a email to the team and see what they say but thinking of removing them and putting some kind of solid strips from side to side for the machine to rest on and stop the flexing.
Bill V

I have the XXL and don’t have any noticeable sag. I suggest that you cut a piece of wood to put under the center of the longest span that brings the center up to level with the sides. That will stiffen it up. Then, run a leveling operation where you mill off about 0.02" off your spoil board with the z zero set at the lowest point. That will give you a level surface to work from until its time to trim the spoil board down again.

I did mount a dial indicator to the collet of the router and it was quite easy to induce a 0.025" deflection in the center of the spoil board just by pushing down on it with a couple of fingers. That’s another reason to support the middle of the span with something rigid. The Z gantry assembly isn’t very stiff either. Its easy to deflect it 0.025" with moderate force. I expected that with a machine like this and I don’t think its a big problem as long as you don’t try to take too heavy of a cut and leave enough stock to do a finish pass with just a small amount of material to remove. That way the forces never get high enough to induce much error.

Thanks Tony. I just put a 1/2 inch piece of MDF across the bottom of the entire frame between the feet. It now works much better and I got a good Hello World to produce.

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