Adjustable Top Beam Idea


I have seen talk about adjustable motors and/or top beam on the forums but no solutions. I think most people get away with standard sizes of plywood without having adjust. I have guards on my Maslow to ensure the chain contacts the sprocket at the right angle, however I’m sure I am inducing a bit of error in cutting by forcing the chain off a angle when doing thick pieces. So I did some brainstorming and came up with an idea that uses: 2x pieces of 2x4 mounts, 2x ball bearing drawer sliders, and 2x clamps. Could also just miter t-tracks but that is way more expensive than drawer sliders.

Support of the top beam is supported by the secondary mount (not the slider) and clamped into place. See attached graphic. Ready for constructive feedback and criticism.

How much movement do you think you need? Your depth of cut is limited by your bit/ mill length. If you need to cut super deep stuff, it likely won’t be full sized, cut a hole in your work piece. If it is full sized and is that big, you probably need a bigger system.

that would work, anything that gives you a bit of adjustment will work (short
lengths of unistrut are cheaper than t-tracks, or you can just have slots or
multiple holes to mount the top beam, one every inch or so would probably be
good enough)

David Lang

True that we are limited by plunge depth and bit length. I think adjustable 2" forward would suffice. That would allow people to router designs into thicker slabs etc.

The most common reason for needing to handle significant thinkness variation is
when you are doing things like carving signs in thick slabs, tops of boxes, etc.
so the depth of the bit and Z axis doesn’t matter as much as just keeping the
chains aligned with the sprockets.

David Lang

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The smallest I could find was a 12" bearing drawer slider.

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