MDF and alu sandwich router

[Tom]

Ladies and gents,

Today I can happily announce the arrival of my leadscrew. :-)
Which means that very shortly the machine build can re-start. The only components I don't have yet are the power supply (50V and 12A max, probably play it safe with 45V and 8A should be fine), and the router itself....

EMC2 is running and recognising estops and limit switches, so all in all I can't wait to get stuck back in.

But first I've got to go to Poland...
Back soon I hope...

[John S]

But first I've got to go to Poland...
Back soon I hope...

Bring us a chuck back............

.

[Tom]

Lots of Poles, stunningly good looking women, and factories in Poland. Sadly I was involved exclusively with the latter...:nope:

Didn't know Poland was famous for chucks either - let me know some manufacturers and I'll do some research (it seems I may have wasted 12kg of my 20kg baggage allowance :naughty:).

Kip cheers for the power supply link. Even including postage that'd come in at the same price as the toroidal transformer alone! (nevermind the cap(s), rectifier, and faff) Cheers!

My finger is hovering over the buy it now button, but I'm a little worried about the voltage. My drivers have an absolute max of 50V, so I was going to play it safe with 45V or so. Those power supplies are trimmable from 50.5V to 56.5V according to the datasheet.

What's the best way to drop 5V or so at 10A? Shall I order something like a 50W power resistor?
http://docs-europe.electrocomponents...6b8003123a.pdf

[Tom]

What drivers do you have?

I bought the "standard" 18-50V, 4.2A max drivers that everyone seems to be selling (black cases, green terminal blocks). Got mine from Arc Euro Trade at a very fair price with free shipping. I recon they compare OK with geckos.

if no good I'll buy em off you :D

Cheers for the offer, but you should buy your own! I'm confident they'll be good!
Seriously though, have you got your 'lectrics sorted yet, or is that the next step?

I'm going to order one of those power supplies and a resistor... Cheers again for the link....

[irving2008]

Nice powersupplies and i've ordered two (can never have too many supplies hanging around!)

Note though you may need to use a reverse energy dump circuit with this supply as it has an over-volts latch off function if the output voltage exceeds 60v. With a large stepper under load the reverse EMF could cause the over-volt trip to shut the supply down (sort of like a self-inflicted e-stop)

It shouldnt be hard to tweak it to go below 50v. When I get it I'll have a look, also will advise on best way to replace the output connector with something more cost effective as the DIN41612H connectors are £10+ each without the shells. The connector on the supply is a male, so it may be possible to use female push-fit spade connectors directly on the terminal pins.

[Tom]

shouldnt be hard to tweak it to go below 50v. When I get it I'll have a look, also will advise on best way to replace the output connector with something more cost effective as the DIN41612H connectors are £10+ each without the shells. The connector on the supply is a male, so it may be possible to use female push-fit spade connectors directly on the terminal pins.

Thanks Irving,

I was hoping spade connectors would fit too, otherwise I was just planning to solder directly to the pins (not pretty), or open the box and find another way.

I'd read about energy dumps for back EMF during deceleration, but didn't think that would affect steppers so badly. Anyway, it would be great if you could let me know about voltage adjustment when you get the supplies.....

[Tom]

OK then,

The summer has been had, the long evenings have long gone, and it's time to get back to the CNC router build.

Over the last couple of weeks I've been getting things back in shape (mainly remembering where I'd put everything). I got the electrical panel built during a day off work a fortnight ago - once I saw the motors singing there's no way I'm stopping!

Here's a video of the YZ gantry moving.
Y travel is 480mm, Z travel is 100mm in this video but it will go further.
These are G00 moves and the speed seems quite good (but it may be losing steps - need to check with some dial gauge tests when its on the x table).
I'll post the current EMC2 accelerations and velocities next time I'm near that computer.



Next jobs:
Mounting the X axis leadscrew and nut.
Then limit switches and a bodged up router mount.
Then (quickly before it all falls apart) I'll need to mill an MDF router mount, followed by decent motor mounts (they're pretty heath robinson at the mo).
Finally, make a few xmas presents on it... :) (time is v short)

Photos:
Pic of the front
Bodged temporary motor mounts
Rear of the Z carriage

[jonm]

hi tom
could you tell what breakout board you used with the euro arc trader drivers, i looked at these are they ok


thanks