In the process of buildibg my Primo and planning a 700 x 700 work area.
WIll deflection of the conduit be an issue at this size? If so, ia it possible to add centre supports?
I have seen them for the Burly, but not the Primo.
My primo was 760x640 and deflection was very noticeable. I don’t know if I ever saw supports either.
I also had a ~700x550 and there was a lot of chatter in the middle.
If you aren’t feeling too committed, change to a LR for that size. 
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Thanks guys - I am wondering if the supports that were used on the burly would work on the primo? The truck design does look to be quite different.
Even if you put supports around the edges, the center gantry spans are going to sag some.
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Sag isn’t the problem. Well not the real problem. Yes there will be some sag, but with my Primo the problem was that the tubes vibrate, and near the centre of the long span, this vibration got to a high enough amplitude to cause problems during some cuts, notably plunges or small circles. So sometimes a small hole supposed to be 4.5mm for a #8 woodscrew would be too big because the gantry was shaking when making the hole.
I could filter out many of the problems with very careful CAM, but still missed sometimes.
As far as sag goes the amount was very minimal, mostly ignorable, and less than the amount of warp in practically any piece of wood that I put through the CNC.
Rigidity is the key.
That said, centre supports for the rails helps make those more rigid, which still helps.
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