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adamh
06-12-2013, 02:16 AM
Morning All

I have a Kit on its was from the USA. I need to source the electronics.
Ive been looking around eBay and notice that there are a lot of packages for around £400
Are these any good, Is there any well known suppliers, Has anyone else bought one from eBay/China

Thanks Adam

irving2008
06-12-2013, 05:53 AM
Don't. It's not that they're no good, just no good for your requirement. The key here is that the motors need to be matched to the machine. As you say in your other thread, you are new to CNC. This is a good example of where a lot more research and asking the right questions could potentially have saved a lot of pain and money.

I'm guessing your cnc kit, from your other thread, is the 4-axis Nema 34 version. The kit supplier does a Nema34 electronics pack that seems a lot more expensive than the eBay ones, and that's because they've sourced low inductance motors (2mH) that will perform fairly well on the 48v drivers they offer.

By contrast the bulk of those 'cheaper' eBay kits are 22mH motors and 60v supply. In reality those motors need 150v drivers. As a result you'll be lucky to get half the feed rate of the 'official' kit.

There are 3 axis kits offering 3.5mH motors which would perform better on 60v, but you'll still need to match up a 4th axis.

Also check shaft dia and motor length. Some of these eBay kits may be physically incompatible as well.

adamh
06-12-2013, 10:42 AM
Morning Irving2008

Thanks very much for your reply. My way of thinking was source the machine which i have done then source the rest locally for help/backup/problems.

I have read a lot about the package that cnc router part supply and its all good comments. I just wanted a local supplier so if i get problem i can call them.

Is there a package you could suggest in the uk or a company that could suppy parts.

Also you mentioned the rigidity of the machine. Would this be due to the v bearing linear system.

I appreciate your time and help

Many thanks Adam

i2i
06-12-2013, 11:30 AM
Strange as it may seem, these guys may be able to help.

Zapp Automation Ltd (http://www.zappautomation.co.uk/en/)

irving2008
06-12-2013, 12:24 PM
Strange as it may seem, these guys may be able to help.

Zapp Automation Ltd (http://www.zappautomation.co.uk/en/)
Zapp's nearest compatible motors are 6.5mH and will need the HV AC drivers to compete...@£220+vat per axis... plus breakout board. Tho Gary might be able to suggest other options...