Mounting motor under table?

**JAZZCNC** · 06-09-2011

Originally Posted by Jonathan

I'm not saying rely on it, just it might help. Clearly the result will be slightly distorted.

I already mentioned about microstepping accuracy (or rather lack of) in post #15...

ye I know Jonathan and wasn't really picking up or discrediting your referance about microstepping more pointing out for high resolution operations like engraving etc then it's better to use the correct pitch screw.

**Rogue** · 17-09-2011

I've been bouncing some of these shapes and ideas around and I'm left with the feeling that, while the idea really appeals to me, I'd end up with the combined table element somewhere in the region of 170+mm deep if I try to fit the motors in the way planned. For some reason that just doesn't feel... right. I have no idea if there is a mechanical reason for this to be wrong, it just seems odd.

This design lark is harder than it looks, especially when you have a tendancy - nay, burning desire! - to reinvent the wheel at every opportunity :confused:

**JAZZCNC** · 17-09-2011

Don't sound over deep to me but it would really help if we had a nice pritty drawing to look at.:whistling:

**Rogue** · 17-09-2011

Oh I do love making pretty drawings... one on the way then, if not in the next hour then tomorrow!

**Rogue** · 17-09-2011

Right. Cobbled something together while the rest of the family were subjecting themselves to XFactor :whistling:

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I've had a glass or three of wine so you'll need to excuse a few glaring errors (yes, one of the motors is physically inside a wall as I forgot to "carry the one" while doodling numbers on the back of a fag packet...). One side is missing for visibility, and because I realised another "carry the one" error made it physically impossible

For size reference, the big blocks along the bottom are 80x80, the others are 80x40. My initial idea for the top table was to use L brackets to connect to the blocks on the rails of the bottom table. No idea if they would be suitably strong enough but it seemed like a good idea at the time (cue cutaway of top table showing L bracket)

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I've not put in the Z, just roughly indicated where the spindle would be. I also want to think about what I can do to make the gantry stronger, bracing etc, for most mass and rigidity within my capabilties - so no welded steel tubes or fancy epoxies :cry:

**Rogue** · 17-09-2011

I also realise it would be flippin' hard to clean as it, but I have plans for tackling that as well! That will be another thread later on in the year!

**JAZZCNC** · 18-09-2011

Hi rogue,

Ah ah I see what you mean know.? . . . Just a quicky as it's early and I'm on way to motoX.

I would scrap the top moving portion as it's too bulky, overly complicates and add's no extra strength or bennifit over the Z axis running across the fixed gantry in the usual way.
Would be cheaper due to less materials and less work.

Yes triangulate and brace the hell out the gantry and base frame.

If you have a need or want an idea for capabilty to have a high Zaxis but with absolute max strength at the cutter, so very little tool flex then let me know and I'll post a suggestion.? . . . If not then won't waste my time. . Lol

Ok time to jump on a road bike to go race dirt bike.!! . . . . .Arg I hate road bikes but got to get there fast.!!

**Rogue** · 18-09-2011

Originally Posted by JAZZCNC

If you have a need or want an idea for capabilty to have a high Zaxis but with absolute max strength at the cutter, so very little tool flex then let me know and I'll post a suggestion.? . . . If not then won't waste my time. . Lol

All suggestions welcome! If there is no real benefit to the design then I'm not obsessed with keeping it. I just thought it was easier to make the table area "solid" than it would be to make the gantry "solid".

**blackburn mark** · 18-09-2011

This design lark is harder than it looks, especially when you have a tendancy - nay, burning desire! - to reinvent the wheel at every opportunity :confused:

:lol: hahahahahah!!!!!!!!!!!! its a problem for sure lol..... i excuse myself the trait because you never know, i might actualy be a genius and unravel a never been seen before solution to an age old problem... alas... it never quite seems to be the case though

it still beats watching the X-factor though