It's begun....

[Washout]

A quick update, as I got some time to work on the machine tonight, but no pics (will post some tomorrow):

I have my first ballscrew mounted, as I figured before I attach the Z-mounting plate the Y Axis needed to be finished. Used a Bosch 17mm bi-metal hole cutter to bore the holes in the gantry sides for the ballscrew and I find these tend to cut ~1mm over size (possibly due to my bench drill being a little wobbly). This is fine however as I need a little clearance to allow for alignment adjustment and have ~1mm rather than the intended 0.5mm.

The floating end is attached using an FK bearing block and circlip and the fixed is also a larger FK type which goes in the stepper motor mount and that is bolted to the gantry side also.

I have come across one of those annoying gotchas where the supplied ballnut mount protrudes ~1mm too far outside the gantry, so I need to work out whether I can "pocket" the ali plate for the z axis by 1mm using the tools I have. I'm thinking of very gently/slowly milling the pocket using my bench drill and an 8mm TC End Mill with the z axis plate clamped to my small cross slide table (normally only used for drilling holes in a straight line) - not sure I should mention a foolish move like this here, but it's a problem that needs solving (I have also toyed with using a low speed on my hand wood router, but I don't trust myself with that method.....).

Hopefully tomorrow I will also get try out the new circular saw on the ali plate (didn't finish work till late and the neighbours would probably not appreciate the tortured machining noises;-) ).

I must also try to resist connecting up the Y Axis just to get something moving under its own steam.....

[Washout]

Afternoon gents (and ladies),

Not posted for a little while but I have not been idle ;-)

Here are a few pics of latest progress and despite a few "rough" bits (z axis plates and spindle mounts), I am finally approaching the end of the mechanical side of things.

I do a have some deflection in the gantry, which is due to my crude mounting solution, but have an RFQ out to help resolve this and will soon order a second ballscrew plus pulley/belt to make sure both sides get equal x axis driving force.

In the meantime, I am now working on the cable runs for the steppers and then the water cooling system and VFD/spindle wiring.

Good news is I have the rest of the year off from work, so I'm hoping I can get at least some light material cutting underway before Christmas.

Lastly before finishing I had better relate some frustrations:

1. I had underestimated the weight of the gantry once all the "stuff" is on it and care is needed when assembling the z axis, as its easy to drop the spindle/mounts etc and if your fingers are in there pain can result - propping things up when securing bolts etc is a must

2. Constructing the z axis is a pain the first time you do it - everything had to go on in order to avoid not being able to get tools onto bolts/nuts etc.

3. Like a berk I assembled the gantry reversed as you can see in one pic, but luckily I needed to almost completley disassemble the gantry to get the y axis ballscrew mounting block in, so put it back the right way.

4. to align the x axis ballscrew I torqued down the fixed end (stepper motor end) then ran the gantry by hand to the far end and tied down the ballscrew and floating end bearing. Hopefully that is the correct method, but it turns and moves easily by hand (I'm assuming turning a stepper by hand is OK).

5. I had a job getting the rails into the bearing blocks on the z axis and actually stripped a bunch of ball bearings out of one of the block, so had to get some replacements, but they are relatively inexpensive and I've sorted out a method which involves only bolting one end of the rails to the front plate, which gives some play to allow for alignment. I then put the remaining bolts onto the rails once they are located in their bearing blocks - not a hard job just needs doing with the front plate in the right place, so I can get access from the rear.

Oh I should (fingers crossed) be moving house soon and I'm really looking forward to the new workshop :-)

Hopefully my next update will not be too far away.

Later



Chris