RF45 Z axis rails mod

blighty · Sep 17, 2015

been wanting to do this for a long time now and after the little crash i had a while back and all the Z axis problems Ive been having since, best get on with it.

bit of history...... a few moons ago Muppet here broke a cardinal rule. I answered the phone when i was doing a tool change. came back to it 30mins later, saw the drill bit in the chuck and hit go. i had put the drill bit in, but hadn't re zeroed the Z height. 6mm drill hit the stock at 4500mm/min (177in/min) pushed the drill through the stock at the same time as the X travel, drill then snapped. then started to drill a hole with the chuck:wall::wall: made a bit of a mess of the head.

after the crash i could never get the head back in, the z travel wasn't smooth any more. i couldn't tram the Y axis of the head in. i could tighten up the jib to solve the problem, but then the Z stepper would stall. think the crash damaged the jib some how...............time to fit the rails.

had a look how others had done it and found one. this guy used a hand router and g clamped it to the slide of the Z and machined away the side of the column. then fitted the rail's to the side's. he then fitted the a plate to the Z slide and mounted the carriages to the plate. took the jib out and was good to go.

so i went the other way... that was to machine off the side of the dove tail and mount the rails directly onto the face of the dove tail.

first problem...... who do i know that has a big mill that will machine my mill in one hit. thx to Alan at MJ

the column was placed on the mill dove tail down. this was done so i could machine a flat at the top of the column. as the column has a slant on the back, this would mean i have a surface that is square to the dove tail for when i turn it over.

in the pic you can see the stack of parallels propping the top of the column up. packing was added till the face of the dove tail was parallel with the table. this bit doesn't have to be that spot on, as you wont be touching the face.

blighty · Sep 17, 2015

once the column is lined up and clocked in, it's time for the "point of no return" bit

blighty · Sep 17, 2015

but before i did all of that, i machined the Z slide. in its self it wasn't that hard to do. what took the 4 hours was to machine of the materiel to get it to size and the only stuff we could find the size i needed was 26mm thick gauge plate. in total, 14mm had to come off from one side and 8mm the other.

then drill some holes in it..... hopefully in the right place.

blighty · Sep 17, 2015

next was to square up the column. this was to insure the rails are square to the base of the column and to the bed of the mill.. once this was done 32 holes were drilled and tapped. one rail was then fitted. the bolts were done up finger tight and the the whole length of the rail was clocked in to the base of the mill.

once the first rail was done. the second rail was screwed into place. the carriages was then put on both rails and a 100mm slip was put between them. this would then (i hope) line up the second rail to the first. i then ran a clock down them just to make sure..