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View Full Version : My huge shaft!



kong
08-29-2003, 08:47 AM
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
08-29-2003, 09:35 AM
Excellent price on those rails and bearings! Sounds like they will stiffen up your assembly nicely.:D

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
08-29-2003, 09:46 AM
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
08-29-2003, 10:27 AM
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!:rolleyes: I broke 2 wheels when they caught an edge and skewed the grinder abruptly. Worked out though. - Doug

Jcadwell
08-29-2003, 01:54 PM
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.