[slavkok]

Hello...

After aprox 3 years of abuse that skate bearing and MDF I was ready for next step. The old machine has terrible Z axis (they are too flexible) and in all MDF is not good material if you cut aluminum and brass. There are 'spots' of WD40 everywhere

So as I need to do major rebuild of Z axis there is little result...

Picture worth 1001 words

[slavkok]

... more stuff here.. I just turned off my computer due thunderstorm here..

So the new design is losely based on Klenibauer "jester" http://www.crankorgan.com/jester.htm
It's dificult to get plans from him if you are in Europe

So the 1'st thing I change was slide bearing material. Delrin is good but here can be problematic due shrinkage with temperature. So I decide to use brass on stainless steel. So I remove all plastic fromm machine. Only lead nut is temporary from UHMW and motor coupling is made from piece of hidraulic hose. I thing I leave that coupler as is. There is more steel inside than ruber (I discover that when I wish to cut that stuff!)

So I do Dry run with that axis done.
I can jog that with 5000mm/m.
I have little backlash in nut very fast. The guide is made preaty stiff so there is NO play and I need more force to move table than older design. Butt as seems the steeper have no problem to move that - fast.

In 1'st place I intend just to replace Z axis in old machine. But when I make that new axis I se how better is than old one and decide to make all machine 100% overhauled. (read - build from scratch)

[slavkok]

Well let's go ahead...

1'st thing when got all tubing is to debur edges. After that I just mark where the holes should be and how manny with permanent pen. (works for me)
As near all holes is in same place related to the end of tube I just made quick and dirty jig from PCB stuff I have. After that I use (DYI) transfer punch to mark exact location on tube. After that I drilled all holes (more than 100) and tap it where is not possible to use nut. (in middle of rails)

... more to come ...

[Thazul]

Hello slavkok,

Very nice pictures, I like your idea of using square tubing and brass strips for your linear ways
Looks like a good way to make DIY Box Ways
I am very interested to see how this works out for you

Can't wait to see more pics and maybe a video!

Keep up the good work

-

Andy

[slavkok]

Deleted message.

[slavkok]

... little new progress

Yestrday I make my hacksaw dull as I hacksawing stainless to make webs. After that I make X frame and square it. With My caliper I can't measure any missalignment. So 25mm X 25mm stainless square tubes for rails seems to be straight.

Next step to make webs for Y axis (probably with fresh hacksaw) and build Y frame.

Slavko.

[slavkok]

... with fresh hacksaw blade I made rest of the webs and finish rails.:tired:

[slavkok]

The next step is to made brass slides. I'm just make simple test to test what is best. One long or two short. Seems that two short is little better. I don't know why but dont care. (Anyway I was short on that brass stock )

After that I fit brass pads to guides...

[slavkok]

... ahh I can't resist to put alltogether to see what I build. It's good also to see if anything is ok and not to interfere with other. I put Z axis on top too ...

I need to slow down a little

Now I need some :idea: how to fit Z axis to base and what to use for base.
As I start this only as replacment part for old one I have no plan how to build complete.

So base on old machine is 30mm laminated MDF (it's the material used for kitchen benchtop) and Jester plans I losely used use MDF/Plywood here. I wish to use something stronger. Also the stand for Z axis in both designs seems to flexible for mee. I want something strudiest. For now I thinking to made stand as inverted U to span from left to right made from HRS 25mm x 50mm (1" x 2") welded together with lots of webs and inside poured with concrete to dampen resonances. For beed I thinking to just use 25mm X 25mm HRS welded in net pattern and with Z bridge and again poured base with concrete. (I intend to pour concrete in all pipes in machine as it's proven to dampens a loot of resonances. But I will do that after 1'st run.)

Any sugesstion ?

[slavkok]

... the top plate (see foto on previous post where you see piece of MDF) I intend to put aluminum 10mm thick. I don't yet have solution how to clamp jobs. Till now I use vise (seen on drill press in previous post) and clamps seen on photo. Vise is good when can be used, but clamps sucks. It's ussable only for wood or printed circuit boards. Some idea? How the other's clamp jobs? Vacuum table seems bad for here but is ussable for biger one machine for wood carving.

[slavkok]

Ahh.. Forget to say. When I'm boored then I can finish the stepper controller too. It's L6207 / AT90S2313 based. I have 42V powersource capable to deliver 1A on all motor phases. The input is opticaly coupled to the printer port on old laptop runing TurboCNC.

[slavkok]

...
Just make motor mounts and thunderstorm strike...
Again... Climate changes for shure

[slavkok]

... I finaly got leadscrew. But wrong one.. :argue: So as I was waiting to long to got that (M10 x 3mm One start instead M12 X 3mm one start) I just install that one and test what I got...

[slavkok]

... and little test of X axis.
The axis need a little tuning but I save this for the end as step controller itself is not finished yet. (I wil make propotional current vs step rate to eliminate resonance problem and overheating motors when idle)

The max speed is 6300mm/m
The bucket if full and has 25kg!:stickpoke

[Thazul]

Looks like you have been hard at work, keep it up!
Very interested in how rigid those slides are in action, looks good.

Best Regards,

Andy

[slavkok]

Thazul thanks for god wishes.

Today I'm make tedious work to make motor mount complete. A lot of drilling and taping job. After that I can't resist to put all together to see what I'm doing. As I don't have 3D CAD I just put junk I have and clamp it together to see how should be and to se if something interfere with other. So now waiting to get right thread rod (M12x3mm) and in midle time to make base of machine. So 1'st I draw that base to see correct dimensions, and after that to buy that steel to make Z axis support. For base plate will try to get piece of granite but if faill (to expensive) I will just make reinforced concrete base some 5 cm thick.

Hey folk what (free ) 3D CAD you uses? I'm just stuck with TurboCadLE (2D)

Slavko.

... and yes. The new one stand on one biger (unfinished) wood router.

[slavkok]

Today was heavy day

I make bed for machine. Its made from HRS U profile. Two piece welded together and vertical support is welded too. The horizontal mount for Z axis will be bolted to supports as I want extra heigth when I mill something very thick. So the Z position is adjustable.

When I weld all together all sems rigid enougth. The problem is when I little knock frame with scerwdriver it's make nice clean tone like piano tunning forks. So that resonance isn't good. So I just try to pour dry sand into one of pipe. The efect is clearly. :banana: The resonance tone almost dissapear and I filled just one pipe!. For now I remove sand to easyer move thing during build. In last phase I wil fill all pipes with sand (no concrete ).

So here is base already painted. It's heavy - over 25kg.

[Thazul]

hi slavkok, looks like you have been busy! nice work

as for a free CAD program, maybe try FreeCAD

I have not tried it but it looks pretty popular at SourceForge (Open Source Development Site)

Screenshots for the FreeCAD look nice too.

I like the idea of adding sand for resonance dampening.

You could also try lead shot if you want to add more mass as well as dampen resonance. Lead Shot Size #12 is small and should work good if it is available where you live. Size #12 is 1.3mm diameter balls.

Keep up the good work

Best Regards

-

Andy

[slavkok]

Hello Andy..

Seems that only you read my posts. I was hoped to have more replyes and maybe some neat idea if I post this thing. Today I have plan to put together al pieces I have and to discover how/where to run cables and limit/home switches. Also I don't know what to use for table and how to make something to clamp work. Still need idea's.
Curent my software is TurboCadLE, VisualMill4, TurboCad. It's ok for 2.5D. But I have future plan to make some 3D parts. So at leadt TurboCadLE doesn't suit that. I was already downloaded DoubleCad XT, AlibreDesign, ProgeCad and just now download freeCad and now I should discover what is good and what not. As I total begginer in 3D I will probably miss something inportant

Maybe I wust writing on wrong forum

About damping resonances with lead shoots I read that this is not good. As laed shoots can fuse together and doesn't dampen resonances. But the weigth is added and this in most cases greatly move resonance frequencies down. I think I have enougth mass (I must run thing to see).

p.s.
Maybe is just my ugly English reason why I don't got more replies. But I do best as I can!

Slavko.

[Arquibaldo]

Dear slavkok:

Don't think you have only one reader - I am also following your thread,
and learning a lot. I'm sure you must have may other readers...

I admire your creativity and the amazing results you're able to achieve
using very modest resources.

Don't worry about your English - it's easy to understand what you mean, and
this is what matters...

Please, keep posting

Nelson