thk actuators vs thk lead/ball screws

[mjs79]

hello cnczone

i have a question sorry if my terms are rough ! im now buying the needed parts to build my cnc mill . i have picked up a thk linear actuator for my z axis , along with thk lm slide rails . im having a hard time finding thk actuators with the stroke lenghts i need 24"and 30" or something close.

i will be using thk lm slide rails for all axis . do i really need actuators or will just the lead/ball screws do fine .the reason i was leaning towards the thk acutuators was for the ease of install .
sorry if the above doesnt make sense its late .
thanks for any info
cheers
mike

[maxcontrol]

Hi,

I made my cnc mill using THK KR33 LM series, very easy to mount and though second hand actuator but backlash should be less than 10 micron. I only have a 10 micron resolution dial gauge.

Definelty worth it not only easy of mounting but also for straightness and stiffness.

[dtoggs]

Thats a great machine,I want to know where to buy the male and female dovetail slide components. The salvage from metal lathes are expensive and generally do not have enough length. Thks,pw

[maxcontrol]

Hi,

I got the complete THK KR33 module from a scarp dealer in my country, Singapore. Mine is about 450mm stroke with a 6mm pitch. There is no dovetail component. They are based on THK caged bearing system. The scarp dealer has lots of different length available. Let me know of your requirement and I might be able to help.

[awerby]

[QUOTE=mjs79;346192]hello cnczone

i have a question sorry if my terms are rough ! im now buying the needed parts to build my cnc mill . i have picked up a thk linear actuator for my z axis , along with thk lm slide rails . im having a hard time finding thk actuators with the stroke lenghts i need 24"and 30" or something close.

i will be using thk lm slide rails for all axis . do i really need actuators or will just the lead/ball screws do fine .the reason i was leaning towards the thk acutuators was for the ease of install .
sorry if the above doesnt make sense its late .
thanks for any info
cheers
mike

[You don't need to use actuators, but I found they make things easier. It's possible to mount ballscrews, bearings, motors, and slides accurately on a straight, stiff piece of metal, and build a platform that slides on them to attach to, but if you get an actuator that's all done for you. I built a machine from similar units myself; I posted something about it in the DIY router section (Deep Z 4-axis machine - no replies yet). I might have some more NSK actuators that would work for you; let me know what lengths you need. Mine have Tamagawa servo motors and steep-pitch screws, but they can be driven with stepper motors if you make adapter plates for them.]

Andrew Werby
www.computersculpture.com

[mjs79]

im looking for actuators with a travel of 24" and another with 30" of travel/stroke .if you have anything please let me know .
thanks for all the info you all have helped me alot .
cheers
mike

[maxcontrol]

Hi Mike,

The scrap dealer do have THK KR33 actuator near to your requirement of 24" and 30", but they are not new actuator. Each is about USD$450 not inclusive of shippment yet.

[mjs79]

thanks for the info . you have PM ^^^^^^^^^^^^