[kong]

Yep, I am still in a state of shock, I spoke to a guy on the phone who said he could help me out with some continuously supported bearing shaft, so i agreed to buy four 6' lengths, with two bearings per length for my planned router, for £100 GBP (~$155 US). I began to plan the router, based on HomeCNC's machine, and using aluminium extrusion, as per Balsamans machine. but I took delivery of these things today, and they are like the incredible hulk of the shaft world! The shaft is 40mm diameter, the supports stand another 40mm tall, and a massive 80mm wide, and they weigh a huge 25Kg (55lb) per shaft!
So my questions are:
What would be the best way to mount these suckers? They need no support on the long axis, but will 1/2" aluminium gantry be sturdy enough to carry the weight of the x axis? I have no room for a huge router, so I will need to cut one of the shafts in two, to give me two 3' rails for the x axis, so can it be cut? I'm thinking grinder or hacksaw, or should I enlist the help of a pro? Please excuse my ignorance, I have never had to deal with anything as huge as these, so any thoughts would be great!

[lsfoils]

Excellent price on those rails and bearings! Sounds like they will stiffen up your assembly nicely.

Most likely the rails are hard. You may find that you can cut them with a hack saw but I would perfer an abrasive cut-off saw. A lot less sweat there... Good luck on your machine! What kind of working envelope are you shooting for?

[kong]

I am aiming for 4' x 2'6" of travel, so with these big rails, I figure around 5' x 3' of rail should do it. Shame to cut them really, but I just don't have the space for a bigger machine! I don't have an abrasive cut-off saw, so maybe an abrasive disk in an angle grinder would do it?

[lsfoils]

I've done that. Except that I went through 5 wheels as my grinder didn't have the speed or stability to cut my rails efficently. I would advise you make sure the wheel diameter is such that the rim speed is at the proper speed (my mistake) and that you hold the grinder using a lot of brute force! I broke 2 wheels when they caught an edge and skewed the grinder abruptly. Worked out though. - Doug

[Jcadwell]

Take them down to the local steel yard and ask nicely if you can get them cut. Cuts usually aren't expensive. You'll get a lot nicer looking cut, and it may even take less time.