My baby 15" x 15" machine

[wilfy]

ok without wanting to annoy you i need to ask this for my own peace of mind..

what is wrong with running the motors slower? why cant you cnc at the speeds your equipment can cope with if it ends up being that you buy the cheap crap stuff??

i understand you are looking out for us and dont want us to make mistakes and end up needing to buy the better stuff anyway, and for this i thank you... but i just wanna know why not if it's easy enough to explain it in simple terms.

just from a rough guess i'm looking at around £100 more than i expected to pay for the electronics, so i just basicly wanna be able to justify it..


also i will look in to finding a driver i presume aslong as i get any driver around 80v and 7.8A they will do the job?? any pointers on a PSU?? and is that all i need to buy.. motors,drivers & psu? the kit i linked seemed to have other stuff

[Jonathan]

what is wrong with running the motors slower? why cant you cnc at the speeds your equipment can cope with if it ends up being that you buy the cheap crap stuff??

If it's sufficient to run your machine as efficiently as you need, then there's nothing wrong. It's just hard to know if it will be..
The motors from England and the drivers are cheaper than the kit you just linked to, so I see no reason not to get the better ones. The TB6560 is generally so unreliable I wouldn't even consider it an option as I guarantee you'll only end up getting better drivers a few months after buying that.

For the PSU a 500VA toroidal transformer, 25V(*2) or 50V is the best option, with a rectifier and capacitors.

[JAZZCNC]

Wilfy I have spent many many hours talking and helping new people to DIYCNC on the phone and via email and THE MOST COMMON (by a long way) single mistake they make is buying the wrong drives and PSU. The TB based boards are one of THE easiest ways to waste money and more importantly time, mainly resulting in frustration and disappointment.

To answer the question regards speed and what's the correct drives PSU to buy then the Honest answer is CAN'T ANSWER.!! . . . . .Until more information is known about the machine and what materials your going to machine.?
I help loads of people either on here on via the phone etc and When I ask folks what they want to machine they generally say "Oh nothing too difficult just MDF, wood, plastic and the Occasional bit of Ali" . . ERmmmm is my reply.?
Whats wrong with that you may think.? . . . . Well it mostly boils down to cutting speeds.!

Given the TB based board and 24V has a crude example.!! . . Out of all those materials you'd think the hard ALi would be the challenge.? BUT in reality given the machine frame is strong enough it will be the most suited to the slow TB based board.? Ali only requires low feed rates and the 24V will probably be ok. This is also why lots of small milling machines and lathes use 24V.
But Wood, MDF, plastics etc require high cutting feed rates so in general require the motors spin faster for longer. There are other things that affect feed rate like screw pitch but in general in these softer materials the motors are working faster. To enable this speed you need voltage and 24V (Excuse the pun) just doesn't cut it and available speed is low and therefore feed rates. Too low feed rates wears tooling out very quickly and leaves a poor finish.
Then you have the workload of the drives.! They are constantly MAX'd out and eventually this takes it toll and in the case of the cheap TB based stuff results in either poor performance in form missed steps etc or has often happens they die quickly by frying themselves.

The extra £100 is worth every penny and will enable a very wide range of cutting capability with the least amount of stress.

[wilfy]

Wilfy I have spent many many hours talking and helping new people to DIYCNC on the phone and via email and THE MOST COMMON (by a long way) single mistake they make is buying the wrong drives and PSU. The TB based boards are one of THE easiest ways to waste money and more importantly time, mainly resulting in frustration and disappointment.

To answer the question regards speed and what's the correct drives PSU to buy then the Honest answer is CAN'T ANSWER.!! . . . . .Until more information is known about the machine and what materials your going to machine.?
I help loads of people either on here on via the phone etc and When I ask folks what they want to machine they generally say "Oh nothing too difficult just MDF, wood, plastic and the Occasional bit of Ali" . . ERmmmm is my reply.?
Whats wrong with that you may think.? . . . . Well it mostly boils down to cutting speeds.!

Given the TB based board and 24V has a crude example.!! . . Out of all those materials you'd think the hard ALi would be the challenge.? BUT in reality given the machine frame is strong enough it will be the most suited to the slow TB based board.? Ali only requires low feed rates and the 24V will probably be ok. This is also why lots of small milling machines and lathes use 24V.
But Wood, MDF, plastics etc require high cutting feed rates so in general require the motors spin faster for longer. There are other things that affect feed rate like screw pitch but in general in these softer materials the motors are working faster. To enable this speed you need voltage and 24V (Excuse the pun) just doesn't cut it and available speed is low and therefore feed rates. Too low feed rates wears tooling out very quickly and leaves a poor finish.
Then you have the workload of the drives.! They are constantly MAX'd out and eventually this takes it toll and in the case of the cheap TB based stuff results in either poor performance in form missed steps etc or has often happens they die quickly by frying themselves.

The extra £100 is worth every penny and will enable a very wide range of cutting capability with the least amount of stress.

thanks for that you replied while i was posting my previous post.. thats explains everything and kind of fills in the missing blanks that i couldnt get my head round.. as it happens using the info jonathan has given me i've pretty much match the earlier price but with the better components