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Old 07-27-2016, 11:25 PM   #31
Blogwitch
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I am now resurrecting this post as things have started to happen.

If you haven't read from the beginning, we wanted to mount up a 16mm ballscrew through the head, to stop the 'crabbing' that is liable to happen if the ballscrew mod was to hang it on the side. The other concern, and why we have gone for the stronger 16mm ballscrew rather than the normal 12mm ones, which allows you to mount them in the centre without too much trouble, but we didn't want the ball nut driving the screw, we need to do it the other way, so avoiding having the screw sticking up in the air.
My mate, John S, has done most of the physical development work, with small inputs from myself. John has already started on his build, I will be following along a little later when my new 12ft x 8ft metal sub workshop has been erected and placed in position.
Just to point out, there will be a few oddities shown on these builds because everything has been taken into account, like having the z axis ballscrew mounted off centre to account for the weight of the motor hanging off the side in a new position. All this calculation should produce a very stable machine compared to what others have been offering, which as far as I am concerned are just lash ups to get a machine to work for the cheapest price. This build is to get you the optimum mechanics with a little more machine work than is normally done. I will be doing just a couple of things differently to John S. as I will be mounting other things on the head, but basically, other than that, they will be the same.

So anyway, John S has started his build, and until I start mine, you can follow his along on there, even now it is an eye opener as like myself, he tries to throw in a bit of humour as well.

http://www.model-engineer.co.uk/foru...?th=119335&p=1


John


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