Quote Originally Posted by Washout View Post
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So I am thinking to fix it temporarily I'll loosen and raise the main 120x60mm cross beam to take some of the slack out (shown in green), but also look at replacing with profile rails and bearings (20mm possibly) - I'll either use Chai if he does these, or Zapp/Gary for convenience, if I can work out which bearing blocks I should go with and whether the whole assembly will fit in the same space?
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Question - I take it the profile rail/bearings are an order of magnitude "stiffer"?
Yes 20mm and the wide type for Y axis if they'll fit but you'll probably use slim type for Z axis to allow room.

Chai does sell these.

Yes profiled linear guides and carriages( Guides not rails, carriages not bearings To please Jonathan.! . Lol) are in a differant league to round type bearings.

Do it sooner rather than later you won't regret it. Oh don't be surprised when you get them if they feel stiff or even slightly notchy as that is normal and just the preload on bearings.!