MH721-mk2 cutting weird

[v2517 1]

Hello,

I purchased a second hand MH721-mk 2 a few years ago, and it has been performing great until recently. Attached is the current result of a few cuts. The one on top is a cross and the one on the bottom is the word "test". I have tried both the usb and serial connections with the same results. And I am using signblazer to send jobs.

I have a feeling either a motor or the control board needs to be replaced. If it's both, I don't think it would be worth it to fix and would probably just replace it. But if it's just one part, I think it would be worth it to keep.

Any help is greatly appreciated.

[Dakotagrafx 7,297]

for grins before you go too far check the carriage to make sure all wheels are on the track, make sure the grit rollers are tight to the rod they attach to by rocking them by hand - this might also give you and idea of if the belt might be loose -   I wouldn't throw in the towel yet but I would go over everything carefully to make sure everything is tight and not broken.  most times if a board they don't cut at all and I don't think I have ever seen a motor go out

[v2517 1]

Thank's for the quick response Dakotagrafx. I checked everything and the carriage is on track and the rollers are tight.

Something I forgot to mention, the machine turned off and on when someone touched it. I assume static shock, which is why I am thinking a bad motor. I am thinking the same, that it's not the board because it still connects and tries to cut.

Here's a vid of it in action.

Again, thanks for the help.

 

Edited March 29, 2017 by v2517

[slice&dice 2,450]

Not a motor -- it's the motherboard, got a jolt from static (as you admitted), this is very common on those machines.

Replace it.

================= Helpful Hint: If you want to create a video in the future for people to view, please upload to YouTube, and provide a link. TIA.

[Primal Decals 621]

Seen the video ----Holy crap. Was that a earth quake in San Fransisco lol.... Definitely a problem. when you get it fixed make sure to check all your ground wires and add ground wires if needed,that cutter needs all the grounding it can get from the stand to the cutter etc. ,Also you can buy a static string from uscutter also that will help reduce or eliminate static as well..

[slice&dice 2,450]

In my shop, I stuff dryer sheets into the ends of vinyl roll tubes.

 

[v2517 1]

Thanks slice&dice and Primal. I will upload to youtube next time.

Looks like the motherboard is 80 bucks, not bad. Will this solve the earthquake issue? I only ask, cause that seems like a mechanical problem. But I could be wrong.

[slice&dice 2,450]

We have seen MH users in several threads discuss their machine making grinding noises and failing to follow the right paths. Motherboard replacement solved the issue.

Your problem seems to be that, especially since you 'zapped' the unit.

$80. is better than $200. (refurb. MH721 - no stand)

[Dakotagrafx 7,297]

 of you order a board take care to order the right one - there are 3 different ones for the mh cutters as they have changed over the years

[v2517 1]

I took off the end cap and located the motherboard. Mine is stamped GOLDCUT 2011A. The picture of the one on the site says GOLDCUT 2010A.

http://www.uscutter.com/MH-Series-Refine-Motherboard-MK2

They look identical and chances are, it will work. I just want to double check before ordering.

Thanks again guys, your help is amazing!

[Dakotagrafx 7,297]

the only way to really confirm would be to call support when USC is open,  the techs almost never come on the forum which is manned by volunteers and longtime users

[Dakotagrafx 7,297]

I know the version 1 and two has to do with the plug location and color is how they distinguish them but on the mk2 version that is the only one I see - again support would have to answer for sure

[v2517 1]

Yea, that is the only one I see also. I will contact USC. Thanks!

[v2517 1]

Replaced the motherboard and I am back up and running. Thanks guys!

[slice&dice 2,450]

Excellent ---  thanks for the update, it makes us feel good to know we got it right!