1200mmX900mmX170mm 4axis cnc

[Nickhofen]

250-300mm will give you a very solid mounting... Given it's a fairly large machine I wouldn't try to save space too much.

Size depends on what motor mounts/bearing mounts/couplings you are using. Don't just guess! Do you know what mounts and bearing arrangements you are using yet?

You may find some creative accounting on invoices.

OK then, I will keep 300mm.
The ballscrews are those ,1605 at different length for Y and Z and for X I am going for 2020.
https://www.aliexpress.com/store/pro...5ce5139enWFCJy
As for motor mounting I am going for the typical all seller have for nema 23, for now and upgrate later.

[Nickhofen]

I am about to pull the trigger and buy the ballscrews, rails and spindle.

Carriage 2 X BLH 20-L900mm linear guideway +4pcs BLH20N Narrow Linear
Carriage 2 X BLH 20-L1200mm linear guideway +4pcs BLH20N Narrow Linear
Carriage 2 X BLH 20-L400mm linear guideway +4pcs BLH20N Narrow Linear

ballscrews Anti Backlash Ballscrew RM1610 -L900mm with SFU1610 Ballnut +BK12 BF12 Support Unit + 1610
Nut Bracket + 6.35*10mm coupler1 X Anti Backlash
Ballscrews 2x SFE 2020 Rolled Ball screw L 1200mm with SFE2020 ballnut + BK15 BF15 Ballscrew Support block + 8mm to 12mm coupler
Ballscrew RM1610 -L400mm with SFU1610 Ballnut + BK12 BF12 Support Unit + 1610 Nut Bracket + 6.35*10mm
coupler

I will use ratio at all screws to lower the screw speed for cutting aluminium.

For spindle I am going for this one:

https://www.aliexpress.com/store/pro...5bdadf47BsiI9F

for stepper motors I am going for Nema23 4NM ,this will be the next thing to order.

If anyone is willing to double check for mistakes,I will highly appreciate that.
Any opinions are welcome!

[Clive S]

The spindle you have link to seems to have 3 bearings this one has 4 http://www.ebay.co.uk/itm/2-2KW-WATE...8AAOSw-W5Us1mz

[Nickhofen]

Thanks Clive.
I am stressed about the ballscrew and rails order and didn't give much attention to this detail, see I do not want to spent money to something that won't do the job. :)
The one you link has the colets also....
I will ask Fred to machine the ballscrew ends to be 30mm .
Is the ratio for all axis a good solutions or it gives more trouble?

[Clive S]

I will use ratio at all screws to lower the screw speed for cutting aluminium.

Nick time for a reality check. First you appear to be using direct couplings from the motor to the screws and then you use the above statement which to me it appears you want to use a belts and pulleys .

Re the list of the screws. Not sure why you need 2010 screws. Generally the screws don't need to be as long as the rails.

Have you done a full cad drawing to show how they will fit? You are going to spend a lot of money and certainly don't want a mistake.

The 30mm you mentioned is the F length of the screw ie just the bit that the coupling or pulley will fit on.

[Nickhofen]

Thanks again for the reply Clive.
My mistake about the coupling, I do not know why I put them in the order.
I will go for pulleys and belts for space reduction, vibrations ,torgue speed change and everything else you guys have analyze here so many times, lol.
I was thinking 20 balscrew for not wiping at critical speed because of length at x axis (1200 mm) ....Am I thinking right?

[Nickhofen]

Generally the screws don't need to be as long as the rails.

I remember that,we discuss it also with Zeefleeboy but at BST Automation there is a photo that show that the length at the description is the total length.
Did I misunderstand something, maybe I have to check with Fred from BST.

[Clive S]

I remember that,we discuss it also with Zeefleeboy but at BST Automation there is a photo that show that the length at the description is the total length.
Did I misunderstand something, maybe I have to check with Fred from BST.

OK when you quote for the screw you tell him the total length (including the F length) and say what F length you want, the standard is about 15mm but that is not enough so ask for the F length to be 30mm (this is the bit where the pulley will fit).

If you PM me your list I will format it for you so that Fred will understand it. You also have to ask for grease nipples.

[Nickhofen]

I am ready to pull the the treager and place order for the rails and balance. I am thinking to use 1610 for X axis and for Y and 1605 for Z, should I go for 2010 for the long axis 1200? Will I gain something?
X axis is going to have two balscrews and two motors, and I am planing to cut wood and aluminium also!

[Clive S]

I am ready to pull the the treager and place order for the rails and balance. I am thinking to use 1610 for X axis and for Y and 1605 for Z, should I go for 2010 for the long axis 1200? Will I gain something?
X axis is going to have two balscrews and two motors, and I am planing to cut wood and aluminium also!

Nick I run 1610 on my long axis with two motors and 1250mm cutting length on X without problems.