1rst build, time to do next step

[JAZZCNC]

Presuming this is all ALU plate.?

Quite a bit of unnecessary weight on there.?
Don't need inner and outer gantry sides or spacers between them. They add very little extra strength only excess flab
Don't need the all the Motor plates etc sitting on gantry side and could just mount motor on inside above screw and thru gantry side if single gantry side.
Don't need the piece that Y axis ballscrew fastens too with small change of design.

The cross piece that rails sit on still looks like single piece of Alu with no bracing.? This is the major weak area which will flex under cutting conditions.
I've built a gantry using plate like what you seem to be wanting which is very very strong. With just a few changes it's half the weight and much stronger and lot neater. It protects the ballscrew and motor by completely encasing it. See pics of it part built and Cad model.
Actual Design was modified to Cad model and ballscrew raised and Motor brought inside gantry connected to screw with timing belt.
Pics of actual machined parts are only for visual purposes.!! IE ballscrew sat on offcuts to show rough position with quite a few pieces like bearing plates and strengthening braces missing.

There's also braces inside the Gantry which are not shown in Cad or pics. The Z axis motor mount is also different and doesn't use upstand pieces shown in Cad instead using a solid 2 piece machined spacer part which covers belt/pulley.

Hope this helps.!

[Gytis]

Don't need inner and outer gantry sides or spacers between them. They add very little extra strength only excess flab
Don't need the all the Motor plates etc sitting on gantry side and could just mount motor on inside above screw and thru gantry side if single gantry side.
Don't need the piece that Y axis ballscrew fastens too with small change of design.

Thank you for pointing it out!

Well, now I have redesigned gantry, this time I took JAZZ ideas (hope you don't mind JAZZ?),
not yet finished but you can see general idea.

[JAZZCNC]

this time I took JAZZ ideas (hope you don't mind JAZZ?),

Nope don't mind at all, only show what I don't mind being plagiarized.!!

Couple of pointers to avoid pit falls which can easily get ya.?

Slot will probably need lifting (or lowering).? Reason being chances are you won't find a timing belt short enough to keep slot in middle and still fit motor in.! The pics don't show it but the slot is offset towards top, the Ball-screw actually mounts above the slot. The ballnut fastens on top side of plate that fastens to backside of Z axis rear plate.

Would use BK/BF not FF/FK blocks mounted straight onto rear of front plate then you can get rid of those plates. Will also make assembly much easier.

With rear covers Instead of 3 flats I'd consider having a nice Arc so single piece of plate bends and follows it's shape instead of 3 separate plates.
On my design I've done it slightly different with the top/bottom rail plates shaped then single 2mm plate bends and follows shape when fastened. This way less work in making the braces and less needed has you don't need any near gantry sides to old the shape.

I'd also beef up the braces just removing enough material so Ballnut passes thru.

[Gytis]

Nope don't mind at all, only show what I don't mind being plagiarized.!!

Come on JAZZ!, show your secret projects

Slot will probably need lifting (or lowering).? Reason being chances are you won't find a timing belt short enough to keep slot in middle and still fit motor in.

I left slot in the same position, just lifted ball screw up as you suggest, I think now there is enough space (in the model now fitted T5-20 tooth pulleys)

Would use BK/BF not FF/FK blocks mounted straight onto rear of front plate then you can get rid of those plates. Will also make assembly much easier.

I did it, now both sides BK fitted. It really makes difference in assembly, and less machining in the parts.

With rear covers Instead of 3 flats I'd consider having a nice Arc so single piece of plate bends and follows it's shape instead of 3 separate plates.

well, arch is nice but I followed the angle of side plate, that's why I made braces like this shape, 3 plates is just in the model, in real life it will be in 1 piece (I hope).


Thanks for the useful tips JAZZ !

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And finally, one question:

timing belts width 15mm or enough 10mm ?, pulleys T5 or different?

Thanks to all !

[JAZZCNC]

Come on JAZZ!, show your secret projects

Could but then I'd have to kill you ALL.!! . . . And I actually do like some of you so I'm doing it to protect the innocent. . .

And finally, one question:

timing belts width 15mm or enough 10mm ?, pulleys T5 or different?

15mm and T5 . . . Don't go less than 18T on the pulleys and I find 20T the best for belt life and fitting etc.

[Gytis]

Could but then I'd have to kill you ALL.!! . . . And I actually do like some of you so I'm doing it to protect the innocent. . .

I do not want to know any more your secrets, I'll better stay in safe side

15mm and T5 . . . Don't go less than 18T on the pulleys and I find 20T the best for belt life and fitting etc.

I was almost right in this direction

Thanks JAZZ

[irving2008]

Could but then I'd have to kill you ALL.!! . . . And I actually do like some of you so I'm doing it to protect the innocent. . ..

oh, which of us do you like then Jazz? :D

[JAZZCNC]

oh, which of us do you like then Jazz? :D

Could tell you Irving but then I'd have to kill you all to protect my self. .

Hi Irving,

I almost sure that you are right, but it will be my first built CNC (so I'm trying to do my best as I can)
what I know about screw and ends?

only one,
fixed + fixed ends its much bater than fixed + floated
(it will eliminates wipping and increas the speed ?)

Thanks for input !

Completely agree with Irving. Fine for industrial machines using servo's with high feed rates 25m/min+ and heavy loads but here the only difference you'll see is less cash in your wallet.!!
With DIY building you'll gain more performance by concentrating on build quality and careful alignment of screws/motors and linear rails than using Industry standards.

One thing wanted to point out which catches new builders out is to think carefully about bolt hole location and fastening of brackets etc.?
Often the obvious place to fasten something is completely the wrong place which makes assembly a right pain in the arse.

IE: You have the Y axis ball-nut bracket (thru slot) fastening from the front side of Z axis rear plate. Doing this means you have to remove front plate from Z axis to access those bolts or drill access holes in it.
You need this bracket to have some adjustment to make alignment with Y axis ball-nut easy and doing this from front and thru a hole will be a pain so would be much easier if it bolted from the rear into tapped holes in the Z axis rear plate.
It's simple things like this that make building and setup just that bit less painful.! . . . Unfortunately finding these things out often comes from building the first machine and at worst case scraping a few parts learning on first build.