Hovering over "Buy"... care to sanity check my thinking?!

[brumster]

Ah yes, sorry, you're right, I meant Mach4. Ok, that's cool then, I'll stay with the parallel port. Glad I kept that old IBM Thinkpad now :D

On Q6, well, I didn't know - I was just after any thoughts/opinions. Sounds like it's just not worth it, so that's cool.

Digital drivers is a new one on me - guess some more reading to do - do they need different motors, presumably? No problem if it's a complex answer, I'll do some reading on the forum, just curious.

I guess any upgrades to the electronics can be considered an investment, assuming the drivers and motors remain matched..... maybe I can keep the motors and spindle, if nothing else, if/when I do make my own.

Am I right in thinking the main thing I need that's really lacking is the rigidity in the gantry, the quality of the runners, lack of support on the Y and just general strength/"trueness" in the aluminium extrusion approach...

Here's the crux question then - for the PCB work and aluminium work (slow, hobby, prototyping stuff, low volume, 0.1" through-hole and SMD designs) is the extra £400 on a 6040 worth it over the 3020? The only real differences I can make out are the crappier spindle, the crappier ball screws and the smaller working size. The latter I couldn't care about :)

[JAZZCNC]

Ah yes, sorry, you're right, I meant Mach4. Ok, that's cool then, I'll stay with the parallel port. Glad I kept that old IBM Thinkpad now :D

No wouldn't use parallel port either. I was saying Go with Ethernet over USB but if choice is between USB and Parallel port then USB every time. Also Don't use Laptop with parallel port and Mach3 they are too unreliable.

Digital drivers is a new one on me - guess some more reading to do - do they need different motors, presumably? No problem if it's a complex answer, I'll do some reading on the forum, just curious.

Digital drives are far superior in performance and reliabilty to Old Analog technology because of the advanced way they handle resonance and current/voltage etc. The difference is quite large and has to be experienced to appreciate the true difference.
They work just same regards motors you can use.

I guess any upgrades to the electronics can be considered an investment, assuming the drivers and motors remain matched..... maybe I can keep the motors and spindle, if nothing else, if/when I do make my own.

Not really because any machine is only good as it's weakist link and there's too many weak links. Also if idea is to re-use on another machine then this needs careful consideration because how do you know what you'll need without having the machine design.?

Am I right in thinking the main thing I need that's really lacking is the rigidity in the gantry, the quality of the runners, lack of support on the Y and just general strength/"trueness" in the aluminium extrusion approach...

It's multitude of things really which all bring it down. The actual strength isn't too bad it's the low quality of rails and bearings etc that let it down.

Here's the crux question then - for the PCB work and aluminium work (slow, hobby, prototyping stuff, low volume, 0.1" through-hole and SMD designs) is the extra £400 on a 6040 worth it over the 3020? The only real differences I can make out are the crappier spindle, the crappier ball screws and the smaller working size. The latter I couldn't care about :)

Forget aluminium it will destroy the machine in no time. The rest it will do. Thou I would say stay away from the Cheap DC spindle and Lead screw versions. All have rubbish electronics so that's just a lottery.

[brumster]

All duly noted. Arrrgh, you're making me think maybe I should just build a scaled-down steel DIY jobbie instead :D !

[Clive S]

All duly noted. Arrrgh, you're making me think maybe I should just build a scaled-down steel DIY jobbie instead :D !

Welcome back to the forum. If you are careful you should be able to make a decent machine for about £1500 so have a look at some of the build logs on here and have a go with a new build thread and put some designs up. Good luck

[JAZZCNC]

All duly noted. Arrrgh, you're making me think maybe I should just build a scaled-down steel DIY jobbie instead :D !

Good it was my intention to make you re-think and Encourage anyone to DIY build. You also don't need to build with steel if you haven't got the tools for it.
Aluminium profile and Aluminium plate still build a very strong and more than capable machine and can be used with minimal tools.
Use correct components along with good electronics and you'll have a machine that will knock all those Chinese machines and several other commercial offerings into tin hat.

[brumster]

I think my idea is to build it in steel just to test the theory and process of construction (I also have loads of 20 and 30mm box, 3mm wall, kicking about), although I fully appreciate it will be overkill at the size I'm looking. So idea is to build a small, desktop build but with the same concepts as the larger one I'd *like* to do one day (in another property, no doubt). But conscious I don't want to get too tied up with the construction/planning that I lose interest and it all dies a death. Having said that, I'm pretty determined in most things, so.... :-S

I'll do some more reading, mull over some ideas - and of course always value other opinions (no offence Jazz, I totally get what you're saying!)...

[Clive S]

It would help if you decided on the physical size so that you can get some advise on the frame.

20 - 30mm box doesn't seem big enough unless you are going to build a 3D printer.

[JAZZCNC]

(no offence Jazz, I totally get what you're saying!)...

No offense taken. It's common for people to dismiss Experienced advice and seek other opinions when they don't hear what they want to hear.!
Truth is they sooner or later realise the advise was good, unfortunatly it's usually cost them money to realise this. . . . Called the price of learning.!

Sad thing is it needn't have done if they'd only listen.

To be honest it's a double edge sword advising people because those that do listen never really fully realise the bullet they dodged by listening so you never really hear from them because things tend to go fine and without issues.
Those that don't are often embarresed so never really say anything publicly and just go with what was suggested first time. (Although do often get PM or email thanking me and asking again.!)

[brumster]

It would help if you decided on the physical size so that you can get some advise on the frame.

Line in the sand, let's say 600x400 working area, give or take 100mm. For this iteration.

No offense taken. It's common for people to dismiss Experienced advice and seek other opinions when they don't hear what they want to hear.!
Truth is they sooner or later realise the advise was good, unfortunatly it's usually cost them money to realise this. . . . Called the price of learning.!

Sad thing is it needn't have done if they'd only listen.

To be honest it's a double edge sword advising people because those that do listen never really fully realise the bullet they dodged by listening so you never really hear from them because things tend to go fine and without issues.
Those that don't are often embarresed so never really say anything publicly and just go with what was suggested first time. (Although do often get PM or email thanking me and asking again.!)

Yeah, sure, I understand. And I am listening, don't worry. The choice for me is whether writing off £500-1000 on a crappy Chinese thing is a valuable learning experience versus investing the time and money into a £1500 DIY job first time - accepting that I might get things wrong, learn the hard expensive way.... I'm going to do some more stewing/thinking/reading.... mainly on the DIY side, get comfortable with the concept that I will have access to sub out any necessary work to those with the right tools.

As per my intro thread, I'm not averse to some fabrication, some welding; I've built numerous cars over the years (I know that's not totally relevant but I'm just trying to convey that I know the right end of a spanner, that's all!)... but likewise it's that knowledge of what needs to be done that's making me double-think whether I can really do it DIY without any mills, lathes, etc... just a bench pillar drill and a hacksaw... :D