[DougO]

Am checking to see if anyone would compare these two boards off Ebay to the 3-Axis Xylotex board for me. They are cheaper than the Xylotex in dollars but does that mean they are really cheaper in the long run.

thanks
Doug

http://cgi.ebay.com/3-AXIS-CNC-ROUTE...QQcmdZViewItem

http://cgi.ebay.com/ws/eBayISAPI.dll...DME:B:SCO:US:2

[pminmo]

Looks like they are both based on allegro's a3977, one a tssop package the other the ked package same as Xylotex. I try to say away from critiquing others products, but looking at the visible aspects of the stepmaster, I'd stay away from it. A LONG WAYS AWAY! The other, I'd question why would you purchase from someone who sells on ebay doesn't have a support site, or supporting information when the price is so close to one that does?

[rcrabb]

Spend the little extra and go with Xylotex. You will not be dissapionted. I have purchased a Xylotex board and was impressed with the quality of the product and the support I have recieved.

[Oldmanandhistoy]

Hi,

Pminmo may I ask why you would stay a long way from the stepmaster drive?
If you don’t want to say here would you be kind enough to send me a brief pm. would be grateful for more information.

Thanks,

John

[DougO]

I definitely appreciate the replies.

I have seen the one that is close to the same price as Xylotex, sell for much cheaper than the asking "buy now" price. Also, the fuses that on that board look like they could save some money down the road. I see in some other forums where the Xylotex boards are damaged and costs the person $55 to get fixed. If these fuses did what I thought they did, they would blow before any damage would be done to the board. This may not be the case.

thanks
DougO

[rcrabb]

DougO, have you emailed the ebay seller? I would be interested knowing what he told you.

[pminmo]

Also, the fuses that on that board look like they could save some money down the road. I see in some other forums where the Xylotex boards are damaged and costs the person $55 to get fixed. If these fuses did what I thought they did, they would blow before any damage would be done to the board. This may not be the case.

thanks
DougO

Possibly, but probably the #1 and #2 most common faults taking out a 3977 isn't a condition that a fuse will blow.

[ger21]

Possibly, but probably the #1 and #2 most common faults taking out a 3977 isn't a condition that a fuse will blow.

I think the majority of those $55 repairs are from people miswiring or disconnecting motors with the drives powered. Fuses won't help you there.

[DougO]

rcrabb - I have emailed the seller but have not heard back. I will let you know what his reply is.

I see where someone had his board messed up by static electricity. It seems static electricity would be hard to keep away from your machines. Would these fuses help in the case of static electricity?

To properly ground your CNC would you run a ground wire attached to you CNC to a ground rod driven in the ground?

thanks

[rcrabb]

Don't let those fuses be your deciding factor. I think most people damage their boards by improper installation. Those fuses are not going to protect the parrallel port side of the board. They are only going to keep you from running too much current through the board on the motor side. Static electricity can easilly damage a board but I you follow the installation instructions and everything is properly grounded you won't have any problems. Is this your first machine? What is your level with electronic circuits?

[DougO]

This is my second machine. I built the Sosylva CNC and use the Xylotex 269 oz motors and board. I bought an extra motor just in case and have gotten nervous now by reading the posts about blowing up boards. Thought I might go ahead and get a backup board just in case, also.

As far as knowledge - I can follow instructions pretty good. Do not know anything about electronics.

[ger21]

I bought an extra motor just in case and have gotten nervous now by reading the posts about blowing up boards.

Where are you reading these posts? All the posts I've ever read point to bad wiring as the #1 cause of blown boards. And I've read almost all the posts on the Xylotex support group too.

[DougO]

This is a couple of the posts. I just searched for "static" and came up with a lot of hits.

http://www.cnczone.com/forums/showpo...44&postcount=6

http://www.cnczone.com/forums/showpo...&postcount=353

[rcrabb]

I agree with Gerry. Don't be nervouse about blowing up a board. Just be carefull following instructions. But it sounds like you already have a working machine with a xylotex board. As far as static and grounding your machine, don't go crazy driving a grounding rod in the ground. Just make sure you use the ground prong on your AC plug. That prong is connected to the grounding rods near were your service enters your building.

[rcrabb]

This is a couple of the posts. I just searched for "static" and came up with a lot of hits.

http://www.cnczone.com/forums/showpo...44&postcount=6

http://www.cnczone.com/forums/showpo...&postcount=353

DougO,

In both those posts they assume static was the cause. I would bet against static, Unless things were not grounded properly.

[ger21]

Yeah, somebody "guessed" it might be static, and they were using Geckos, not a Xylotex.

[pminmo]

Static electricity is an issue with mos devices, but primarily when in an open circuit enviornment. Fuses won't help. The 3977 which the boards that were mentioned, along with the xylotex boards and my open source 3977 boards are suspect to static damage when the chip is not installed on a board, and to a lesser extent before the board is wired. The motor driver outputs before they are connected to a motor still leave the chip subject to static electricity, to a lesser degree.

[DougO]

Thanks guys, makes me feel better. I live in Mississippi and don't know if it's the humidity or what, but at certain times of the year a person can't touch anything without getting shocked by static electricity and I definitely didn't want to spend $55 and lose a couple of weeks without the machine if I could help it.

[DougO]

DougO, have you emailed the ebay seller? I would be interested knowing what he told you.

rcrabb - I have emailed the seller two times asking information about the boards and purpose of the fuses and no replies from either. That is nuff said for me. Think I'll stay away.

[rcrabb]

Another thing to think about in the future is to buy a 4 axis card for a 3 axis machine. I bought the 4 axis card from xylotex. It gives me room for expansion and i'll have a a spare axis if I burn one up.