Y axis movement issues

Machine: Omtech k40

Board: Cohesion3D

Firmware: _Smoothie

Problem/ Question: Brand new install, no modifications to the config.txt file.
Homing works fine, when I move the X axis 10 mm its moves exactly 10mm. When I move the Y it moves exactly one half the distance I told it to. So if I move the Y 10mm , it moves exactly 5mm.
In Lightburn when I use set laser position icon and I click the center of the bed the X axis starts moving correctly but Y goes in the opposite direction starts grinding against the top/back of the Y axis.
I can jog in the any direction correctly with the Y but it only moves half the distance.

Here are my basic settings.

But when I use the Jog controls in Lightburn both X and Y move correctly but Y only half the distanc

It seems you have wrong params in the stepps/mm setting of the y -axis. If the settings are the same as on the x-axis, your machine may have a different stepper motor on y than on x (400stepps/rev instead of 200stepps/rev). To compensate that, you just need to set the stepps/mm for y-axis to the double of the actual value (in config.txt of smoothieware).

Yes, that’s what I have done and it correct the issue. I had to set it to 315.150 steps/mm. X is 157.575.
Seems strange that it would require such a high setting.

Well, if one is a 0.9° degrees per step / 400 steps per revolution stepper motor and the other is a 1.8° degrees per step / 200 steps per revolution stepper motor, that’s what would happen. Normally in a K40, both steppers are 0.9° steppers, but 1.8° steppers are far more common and are widely available for 3D printers.

Is this machine new from OMTech or did you get it from someone else? If this is second-hand, they might have replaced a suspect or dead X stepper motor with one that was easy to find.

Yes this is supposed to be an OMTech unit bought through Amazon “Orion Motor Tech Store”, but honestly I don’t believe it is. I have contacted OMTech and asked them about several things that just did not add up and they said that they have authorized sellers on Amazon and Ebay and would check into the seller on Amazon. The unit I received did not have any OMTech branding on it anywhere and I had several issues with it right out of the box. Bad power supply, Mirrors that looked like had been dipped in oil and mixed with some kind of dust, weird stepper motors. I paid more than average for the unit through amazon from OMTech just because I thought I would get a unit that had some level of quality control done on it by OMTech, but I am pretty sure that is not what I got. And so far the response from OMTech directly seems like they really don’t care. They did offer to send me a power supply which is going to take approximately 2 - 3 weeks to receive, they made no offer to replace all the mirrors that are filthy and have weird gray spots on them.

This is where I bought through off amazon.
Amazon.com: Orion Motor Tech: LASER ENGRAVER&CUTTER

That sure looks like the Orion Motor Tech store on Amazon. That’s disappointing; we’ve had several forum members with stories of really good customer service from them. @HalfNormal I think you had a good experience? Or am I crossing wires here?

You are correct that I have an early OMtech laser. Unfortunately as @nickm324 stated, there are numerus resellers. Mine was purchased over 4 years ago from eBay. At the time it was directly from OMT so I dealt with them. My experience like most have been positive. There are the few that have had issues. You mention that even though OMT is not sure about the reseller, they have taken measures to help out. Amazon has a good customer resolution system as long as you go through them with your vendor discussions.

I wish you best on getting the laser running to your satisfaction. Keep us updated!

They have offered to replace the power supply although not in a timely fasion in my opinion. They basically told me the mirrors have a protective film on them that I need to remove, of course there was no protective film. Other than that I guess it was mostly disappointment in the fact that I thought I was going the saftest route by buying from them directly via Amazon and it would have been a solid machine that had been inspected to some extent. It has been one issue after the other since it arrived. I had hopes of having it up and running shortly after arrival and now its basically taken a couple of weeks to work through all the issues and order replacement parts myself. So I would not call it a good experience up to this point.

Here are the mirrors they told me to remove the protective film from. The right one I tried to clean.
image

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Update
So I was contacted by OMTech via email and they have decided to give me a refund of $30 on my purchase of my K40 to buy new mirrors and they have already shipped me out a new power supply.
So I will say they are good about doing what’s right, even if they are a little slow to get around to it.

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