Hi guys,hi Gerald,

I just would like some points of view concerning the specs of Techlf 34H098 STEPPER MOTOR product for the mechmate : www.techlf.com/motors.php3.
i have difficulties to compare us and french specs !
Concerning the quality of Techlf controllers, i need a point of view too : which is the most effcient for the mechmate ?
Thank you for your answers.
Pierre GRAND.

My first impression is that they have good products at good prices. I will have a better look later when when I finish my grinding experiment.

From the spec sheet, the 34H098 looks like a nice motor. The figures that I've run on that motor show that if rated at 3.5V, which is 0.65 ohms X 5A, then it could use a power supply of about 65V (20 X 3.5V). At 65V, using Mariss's latest formula, (0.192 X 65V) / ((2.4/1000) * 5A), would give a corner speed of about 1,000 RPM. By comparing the figures for the 34H098 motor with the figures for an Oriental Motor PK299-F4.5 motor, I'm guessing that those figures would be for a half-coil connection, rather than parallel.

If I've guessed correctly, the 34H098 connected with the parallel configuration, would use a maximum power supply voltage of 45V at 7A and would give (0.191 X 45V) / ((2.4/1000) * 7) = 511 as a corner speed.

Those figures are very similar to the PK299-F4.5 motor that I have. The PK299-F4.5 motor is my motor of choice, meaning that the 34H098 would also be an excellent motor.

Of course, everything is based on the spec. sheet and of my interpretation of the figures.

As for the stepper driver, I can only say that the specs look good. I'm very partial to the Gecko G20x stepper drivers, especially the G203, so I'm biased in my opinion about other stepper drivers. But the specs look very good for the Techlf stepper driver.

Thank you Mike and Gérald for your quick answers.
I know it is going to be my solution for steppers motors following what you have explained me.

That Chinese 34H098 motor looks okay, as Mike says. Note that the shaft is slightly thicker (14mm) than those we normally talk about here. You will have to be very careful with mounting a 24 tooth Module 1 pinion gear, because there will only be 3mm thickness for the locking screw. I am using 12.7mm shafts, so I have 3.65mm - yours are going to be 20% thinner. But I think it will work with M5 screws if the metal of the gear is hardened after cutting the hole and screw thread.

Isn't it striking how close those specs are to the 34HS9802 from motionking?

Unfortunately, the Chinese have a bad reputation for "sharing" designs, specifications and instruction manuals from one manufacturer to the next. It is very difficult for us inexperienced folk to say with any confidence that a particular specification belongs to a particular manufacturer. That is why we pay a premium price to someone like Techlf, trusting their experience in buying from reliable suppliers.

But, this situation is going to change.... Only 30-40 years ago, Japan was in this situation. Today we generally know which are the reliable brands from Japan, and the country enjoys an excellent reputation as a world trader. I am NOT saying that the Chinese must not be trusted - I am saying that we must work to find WHO to trust. Smart people now are busy selecting (and developing) business partners in China.