Full Version: FINDING HOME POSITION
From: ChiefD (CHIEFDCCD) [#11]
23 Jan 2007
To: ALL
Okay, I just spoke to the Epilog Techs on the phone. Although I am very frustrated with the issue on a brand new laser, I must say that this forum has been pretty accurate about Epilogs great service.
I called them this morning as a followup to my email. They were right in the middle of reading about my issue. It is definitely the motherboard! They are going to overnight it to me and I should have it by 10:00 tomorrow morning. I will then have to get them back on the phone for the install, but being the computer geek I am, I don't anticipate a problem.
I do have a question. I had JUST updated the firmware a day or two ago. Will this come on the new motherboard, or will I have to load it again. I should have asked them today, but forgot.
Epilog told me that this IS an ongoing issue with the Helix models (not sure about others). They ARE on top of this issue and addressing the problem. They thought they had it fixed, but problems came up again. They have now changed the chip (not sure which one) in the new boards and are pretty sure that the issue is fixed with the new board. Basically there is a glitch and the XY thinks it is already back as far as it can go, but it is not. The result is that the arm moves forward about 1/2 inch from home. Also it cannot reset back to home from know matter where the XY is located on the board. Where ever it is, is where it thinks home is.
I would suggest to any other owners of the Helix model that are approaching warranty expiration to call Epilog now. Express your concern about this KNOWN issue just in case the problem comes up after warranty expiration.
Jody
From: Harvey only (HARVEY-ONLY) [#12]
23 Jan 2007
To: ChiefD (CHIEFDCCD) [#11] 23 Jan 2007
It sounds like the chip that detects the limit switch is detecting it always in contact with the carriage. If it is not a run of very bad chips, it is a design flaw in the circuitry that does not take into account the faint leakage of the chip. Usually one additional resistor solves the problem, in some circuits two resistors are needed. They may need an engineer to solve the problem forever, rather than a tech.
I have seen this sort of problem slip through in design too many times where a design looks great on paper and the chips are dead on spec, then you make a production run and find that some chips are just a little bit out of spec and you get yourself in trouble. I started to design with parameters that were at least 3 times worst case and found that solved many of those problems. (Then you get a run of transistors with a rated gain minimum of 130 that have a gain of 5-10 and are blown out of the water again. This was so bad with some RF power transistors that we got a curve tracer and verified gain and leakage on every one. 75% of the batch were out of spec and returned. The next batch came in bad also, so I put a tiny red dot of nail polish on them, and returned them. Guess what red dotted transistors came back?)
From: UncleSteve [#13]
23 Jan 2007
To: ChiefD (CHIEFDCCD) [#11] 23 Jan 2007
Glad they are working on the problem for/with you.
From: Carol (CAROLYNNE) [#14]
23 Jan 2007
To: ChiefD (CHIEFDCCD) [#6] 23 Jan 2007
Last time I spoke with Epilog the concern was expressed it may be an outside issue and they'll look into that possibility if it happens again. I don't quite get overnight delivery on the parts - but the guys there really have been great since day 1. I am really relieved to find out this has in fact happened to other people.
Things are working well at this point, so with any kind of luck, the issue has been resolved.
IF I run into any problems again I'll let you know how it goes!
From: Griffo (LASERWEST) [#15]
23 Jan 2007
To: ChiefD (CHIEFDCCD) [#7] 24 Jan 2007
Hi Jody,
No they just said it may have been a problem board and replaced it.
The service guys over here are pretty good and the responce time was great.