With the cost of an threaded aluminium table very expensive I set about looking for a suitable alternative to the ex factory MDF base. I purchased a piece of HDPE which didn’t work out (Discussion here)
A little later I purchased a sheet of laminated bamboo about 25mm thick. (More discussion here) but never got around to fitting it to my 3XL for about 7 months. By the way the bamboo was really fairly flat to within about +/- 0.25mm (0.01”) and heavy as.
Then I discovered this and at a fairly reasonable price too. I purchased 3 x 1metre lengths. 1 metre fits conveniently within the 3XL’s width. This then gave me the impetus to put the aforesaid bamboo to use.
I removed the factory MDF board and replaced it with the bamboo laminated board. On top of this I butted the 3 aluminium extruded lengths against each other. This gave me a surface area of 1000mm x 450mm, not all of which is usable on the 3XL.
The extrusions are secured to the bamboo board from underneath with each 3 x M6 screws in each end of the three sections. Initially I intended fixing in the centre of each extrusion as well but the bamboo board is very heavy and I was concerned that the extrusions would conform to the bamboo’s not accurate surface. The beauty of only fixing at the ends is that one can shim the underside of the extrusion at 12 different points to get a perfectly level base. In my case I think I only used 2 or 3 very thin shims of sub 0.010” thickness.
As can be seen from the images on top of the extrusion I fitted planks of 16mm MDF as a spoilboard. I haven’t done it yet but intend to surface the MDF with my 1” flycutter. All in all I am very happy with my new base and the 60mm apart fastening slots makes fixing jobs a breeze. I can highly recommend.
Thinking about all of this though I suspect that there was little to be gained by replacing the original MDF base, maybe it is a little more sturdy but I shall never know for sure.
The image below shows the Bambbo base with the 30 x 150 Aluminium extrusion mounted thereon. The frame under the 3XL is a temporary frame to allow me to access the extrusion mounting screws.
Below a view of the extrusions being fitted to the bamboo base.
Fitting the 16mm MDF spoilboards. Note the slide-in captive nuts made with 16 x 3mm aluminium bar tapped to M6.
Below the completed unit. I also fitted an LED strip under the gantry, which is rather nice.