Comparative CNC Test
Test of a copied High-Z CNC machine built by a competitor
We felt induced to do this test because of the following story:
2004 we found out there’s no supplier on the market of CNC portal milling machines with a proper cost/ performance ratio and so we decided to change this fact and apparently we get it done.
After a development phase of 10 months we introduced our High-Z on the market on January 2005. Since 12.01.2005 till today ( 1.9.2007 ) we have sold over 900 High-Z CNC milling machines worldwide.
We owe a big part of this success to our management floor which always makes an effort to adapt electronic and mechanical parts of High-Z series and to optimize them long- term in order to ensure further high level quality and low prices.
Unfortunately our High-Z series is badly copied by some competitors and sold for similar prices. This fact induced us to buy one of this machines and to test it.
The alarming result is reported on this page.
Self aware we covered up some components of the machine or show just small exerpts in order not to supply our competitors a disadvantage on market. In the meantime there are 5 different suppliers in internet who offer a copy of our machine.
| All following results were achieved with 6 witnesses and are in accordance with truth. |
What you should pay attention to buying a CNC machine and found defects:
Visual test
We picked up the machine from producer who gave it to us without any friendly receipt. Back to our workshop we unwrapped the machine immediately.
Instantly we saw:
Besides is unfavorable Z-axle construction the machine is relatively identical with our original High-Z CNC milling machine.
Following we found out there was no single useful data file on the CD. We didn’t get any new CD despite inquiry till ( 3 weeks after buy ). But we certainly get them in e-mail.
Connection with controlling and first function cnc test
A supplement explains where you have to connect the inscribed plugs on the controlling. An inscription on controlling is completely missing. After the connection of all plugs and setting of parameter (setting data wrote down on three DIN A4 sheets of paper) we did our first try.
The first necessary reference drive failed on the z axle and was interrupted by us. We switched off the controlling and realized that the z axle is mechanical pinched. The spindle severs from the rack after approx 12 turns, the motor is not able to drive the z-axle. We found the reason very fast after opening of the distribution boxes: the motor was totally wrong installed!
Precision cnc test
Precision test of 0,02mm named by “producer”
Our High-Z advertising promises to customers a precision of +-0,02-0,03mm. The producer of this copy promises this machine has to be almost three times preciser than the original High-Z. So we tested following components at first: precision of bronce nut to trapezoid threaded spindle and precision of linear guide ways.
Axle backlash between y-spindle and nut approx. 0,26mm VIDEO
Axle backlash between X-spindle and nut back approx. 0,13mm VIDEO
Axle backlash between y-spindle and nut approx. 0,26mm VIDEO
Backlash cnc test
Test of reversal backlash ( producer’s giving 0,02mm ) visual
We promise to our customers a reversal backlash precision averages approx. 0,025mm. It varies in our adapted special nylatron nut from 0,01mm till maximum approx. 0,05mm.
The producer of the copy promises a double precision in comparison to our original high-Z. Because of the results of axle backlash we expect this giving to be false too. Furthermore there is the extreme height backlash within the used bronce standard nut and the spindles.
Radial play between X-spindle and nut approx. 0,8mm VIDEO
Reversal backlash between X-spindle and nut at the front approx. 0,28mm VIDEO
Reversal backlash between Y- spindle and nut approx. 0,3mm VIDEO
These named results of reversal backlash were later on tested with the software WIN PCNC with a drive without interference and a following direction change.
Further heavy defects
After we found out such rough mangles we wanted to take a near look on the electronic. We don’t know whether the existing CE-declaration is true because even we had some problems with our controlling to get a positive result of the EMV-end test.
Well, we doubt the legality of the certificate and pass the whole procedure on to the Bundesnetzagentur ( Federal Network Agency) and Amt für Arbeitsschutz (Department for employment protection) for testing because we fear seriously there are mangles in whole electronic.
A totally new defining of the term “floating bearing” VIDEO
One more “jalopy“
The final video of a further construction’s imitator of our machine. The video presents a self- production of this company. We paid attention because 3 persons interested in our High-Z mourned the precision of this machine by one special company. One customer even offered his own mangle afflicted machine for presentation. At this opportunity we took this video. This competitor promises a precision of 0,02-0,03mm while milling in brass or aluminium because of machine’s stability! VIDEO. We can’t prove this ability. We traded the machine which is now part of our CNC-STEP company.
Conclusion:
We were shocked how boldly traders deceive their customers. We don’t know how they want to achieve on axle precision better than 0,2mm on effective diameter with a convential DIN 103 screw nut, a not specially adapted TR16 red brass or brass nut ( 7H ) because the tolerance values for rolled spindles ( 7e ) and turned nuts are determined ( in DIN 103 ) ! This is an information paper about tolerances.
Let’s not speak about electronic parts’ quality…
Buying a CNC milling machine you can trust a smiling trader who says : “20 years experience in machine making” , or your own intuition. The most useful way to a tailor-made and high quality product is in our opinion the own convincing and trader’s possessed references.
We trust on individually adapted components. We order undersized nylatron nuts and adapt them individually to the spindles. Same way we fit every single box to the used linear guide ways. This needs tie and of course a certain investment in the product !!
After consulting us you are welcome for a presentation of our machine production. On your wish we would put a measuring instrument on a finished machine to prove the precision. Or you can send us a data file and the material you want to work on. We would create a video for you about working and feasibility with our machines.
Our name will further stand for high quality.
Einige Vergleichsvideos zu unserer original High-Z CNC Anlage
Aus diesem Grunde sind Arbeiten wie diese mit unserer Maschine absolut exakt durchführbar:
Reversal backlash on X-axle at the front 0,02mm. VIDEO
Backlash determination on Fräsmotoraufnahme approx. 0,02mm with approx. 2kg weight. VIDEO
Backlash determination on Y-axle approx. 0,02mm with approx. 2kg weight. VIDEO
Circular milling
Circular milling in solid aluminium)
Because the mechanic and spindle components are free of backlash and specially adapted by us it is possible to round mill in thick aluminium ( H8 ) very precise with our High-Z series!!! Video here !!
Make a call or send us an e-mail for questions or High-Z CNC milling machine presentation date agreement.
Thank you
