New XL/XXL Spindle Plate

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HDVideo
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Joined: Wed Dec 02, 2015 7:33 pm

New XL/XXL Spindle Plate

Post by HDVideo » Wed Mar 02, 2016 8:28 pm

I've been studying the drawings provided for the two expanded SO3 models, trying to figure out what has been done with the new spindle plate. It appears that the spindle mount has been moved to just above the lower v-wheel mounting holes with the portion of the spindle plate below the lower v-wheels chopped off. For this to work, it seems the router will need to be inserted fully into the spindle mount, leaving much more of the router extending below the mount.

Does anyone think this might create a new weak point in both X and Y directions, given the lever point is moved up considerably? The spindle mount has been discussed before as a potential source of flex and this seems it could only exaggerate that problem, if indeed it does exist.
2016-01-22 10_29_15-Autodesk Fusion 360.png
Original SO3 design with support brackets added.
2016-01-22 10_29_15-Autodesk Fusion 360.png (237.69 KiB) Viewed 619 times
2016-03-02 13_02_34-Autodesk Fusion 360.png
New XL/XXL Spindle Plate. This drawing does not show the lower portion of the spindle plate removed.
2016-03-02 13_02_34-Autodesk Fusion 360.png (145.5 KiB) Viewed 619 times

twforeman
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Re: New XL/XXL Spindle Plate

Post by twforeman » Wed Mar 02, 2016 8:38 pm

That appears to be a correct assessment, but there are also flanges on the sides of the new plates.

I'm not a fan of inserting the router further into the mount like that.
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HDVideo
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Re: New XL/XXL Spindle Plate

Post by HDVideo » Wed Mar 02, 2016 9:06 pm

There were two potential problems discussed with the original design. First, flex in the plate, which should be much less with the flanges. The other problem was the fact that the router mount is not thick enough to accommodate more than one row of mounting bolts, possibly allowing the mount to flex to some degree.

With the higher mounting of the router, I don't see any way around inserting it fully in the mount, provided you want to retain the maximum Z travel available with the design.

One possible solution might be a thicker router mount with the plate extended a little further down to allow more attachment points to the plate.

chamnit
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Re: New XL/XXL Spindle Plate

Post by chamnit » Wed Mar 02, 2016 9:13 pm

I think the main difference is that the spindle mounts is now in-between the wheel bearings. So you no longer have a thin steel plate cantilevered out a few inches, where there is not much support on the spindle in the y-direction that keeps z-plate from flexing (Thats why the brackets everyone has been adding works). The new shorter design brings the weight of the spindle much closer to the loading points. No more cantilever loads. In theory, you should have less flex in the z-axis, particularly in the y-direction. The x-direction shouldn't be effected by the change.

Along with this, I recall seeing the z-mounting plates having both sides bent inwards to create two flanges. These flanges should further rigidize the z-carraige, so the only flex should be seen in the wheel bearings themselves. Not everything else.

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