Example from my build

http://farm4.staticflickr.com/3688/8...afdd9f7ce0.jpg
Y chain

Thanks Pete; Looks good! I'll order more cable chain to do it.

hey everyone,

I'm moving my table this weekend to it's shop. So looking forward to that as it has 3 phase electricity for the spindle which is nearly wired up.

I have one question, Ive just purchased a gas spring which said 150nm for my 4k spindle. It seems quite stiff, am mounting it now. If the spring is too stiff, will it damage the Z motor or anything?

Thanks,
Chris

You can not damage the electrics/magnetics of a stepper motor by having too much external load. It may skip steps and you get some rough noises, but the motor has no damage.

In my opinion its better to have a less power then too much power on a Z gas spring. Motor moves my Z even without gas spring so he has enough power, if you get too strong one it may in some cases loose steps when plunging, very difficult to notice sometimes :)

the declaration on it may be misleading, put 15kg on it and see will it slide in

When you weighed the assembly, did you order a spring to match it? It should move freely when assembled. Mine is within a pound and moves easily by hand when assembled but does not drift down. The spring on each of our assemblies is different based on the build. I have a 30 lb spring.

Painting and Priming.
 

Just finished moving the machine, painting it while it is apart. Man that was a heavy mother. I calculated the mass of it based on profiles and tube width and it is over 1100 Kilos! The two side frame pieces with main X long beams alone are 700 kilo! Smelled the clutch of my friend's 4runner big time last night:eek: Anyway, sorry it took a while to get back to you guys.

The spring won't go down on it's own just by itself. But when I put the assembly on top of the sprint and push down, it will go down with a wee bit of force. Not sure how much, maybe 5LBS off. I bought the spring from Ebay in China as that has been the easiest way for me to get reasonable stuff these days. Can't buy a mcmaster car one here unless I send it to the US first then have someone send it to me.

The whole assembly weighs about 30 LBS I guess. I could add weight to it to make it heavier until I can find a spring that would be better.

Last night after moving, I rolled one more coat of black guard on it to cure rust as I noticed a slight layer of rust developing from keeping it in the garage where it is moist from all the rain. I'm going to put one more layer of black guard on today for good measure, then re-prime/seal it with a 2k primer prior to painting with a 2k paint, so today is prep.

I would believe that you would want it to return up if anything but I may be wrong. I thought I read that somewhere.

You can try Schutties fasteners in Moorabbin, Melbourne (03) 9553 2032 for a custom shock (~$50 a few years ago). Helpful people. They may ship to NZ.

It takes some effort to move my Z down and it only returns up slowly after power is removed. Been fine for 2 years now.

Your gas spring sounds about as good as it is going to get, if it is only 5lbs off. They are not made very precisely and they do "settle" a bit (they get smoother, less friction). Realise that your stepper motor, when switched off, will probably take more than 5lbs to turn.

Yes, I think the shock should be ok then if that is the case. I could get a custom one here in NZ pressurized to whatever I needed, but it's $115 compared to the $20 incl shipping I paid for the shock outside the country. My rig weighs in at 28LBS and the shock is rated for 33, so hopefully I don't miss steps. Probably worrying for nothing.

Getting my 2k primer today, it should hopefully smooth out some of the surface texture. Going to shoot 1 coat of enamel primer over the blackguard, sand with 600 grit, then 1 coat of 2k primer, then paint and clear coat. Should be a smooth finish I hope.

That little bit of resistance from the gas shock is not going to cause any problems with steps especially with reduction.

Made some progress painting. 2k primer, 2k paint turned out nice. The guy at the paint store told me the wrong ratio to paint on my other colour, so half the table is painted but turned out looking bad. Have to get some more paint to fix it. Moral of the story, always look at the paint tech sheet prior to painting.

http://s21.postimg.org/8hwl87a03/IMG_2278.jpg http://s21.postimg.org/a5vqmunvn/IMG_2280.jpg http://s21.postimg.org/vi38kj7tv/IMG_2282.jpg

Finished soon!

Chris

I hate it when you listen to someone who should know what they are talking about and don't.
Glad it worked in the end.

Well, the machine is finished painted, and cutting nicely. Will post some photos shortly. Does anyone have a file for a waffle grid vacuum tabletop they can link me to? I remember seeing one somewhere but can't seem to find it again. Thanks!

Chris

Would sure like to see a few pix :D

The Machine cuts
 

Here are some pics, and I have a mov of it cutting that I will post later. The colours are Lemon Yellow, and carbon black metallic. You can see the metallic in the sun and in the lights. Looks sharp though next time I will avoid metallic paint a I had to paint the black twice!

http://s17.postimg.org/t6ka4up9r/IMG_0409.jpg

http://s17.postimg.org/8xwwj4pyn/IMG_0411.jpg

http://s17.postimg.org/509mtq35b/IMG_0412.jpg


http://s11.postimg.org/gkivde5k3/IMG_0402.jpg

http://s11.postimg.org/wu91gag83/IMG_0405.jpg

http://s11.postimg.org/llq9erd0j/IMG_2283.jpg

http://s11.postimg.org/nvedpilyb/IMG_2284.jpg


screen capture tool

Here is the video of it cutting. Very nice cuts! Fast too! This was only about 4000 mm per min cutting.

https://vimeo.com/73555725

Nice wook....now the real reward starts....
enjoy ;)

Chris that is awesome! Congrats!

Very nice.
I have much to do and learn.

Great pix. So awesome.

Nice and strong machine. Congratulations!

Thanks for al your support folks. Really appreciate it.
Chris

Congratulations that looks good, cuts nice and clean.
Good luck

Wow
 

The color is awesome. consider pin striping?

Yes, I have thought about some pin stripes or graphix. Originally was going to give it an Ironman theme, lol.:D Working on a cool Mechmate logo decal. Should be interesting.

More Cutting.
 

Working on some 3d carving, it's such a cool thing to watch the machine cutting 3d. It's so precise and sharp. I managed to get my VFD running through Mach3 via PWM so quite happy with that. My spindle, a 4kw Chinese air cooled so can't go less than 8000 rpm, does that mean when I warm it up, I should start it at 8000 rpm or is that just for cutting?

Very happy with this machine. Was well worth it.
http://s8.postimg.org/v6c049tap/IMG_0425.jpg http://s8.postimg.org/k85bztu35/IMG_0429.jpg

Your spindle can not go under 8000rpm? Do you mean it doesn't move at all?

No, it will go under, it's just that I was told not to cut that low because it won't air cool if I do.

Great job Chris, you'll be like a pig in the proverbial playing with it.

Did I miss something somewhere? Was wondering why so many buttons in your on machine boxes......

Cheers

The bottom are just LEDs. Same amount of buttons on the plan.

Ah ok. So each LED lights up on a button press then. Cool idea!

I'm just imagining how much hair I'll pull out if I put those light in...
Good work!

Thanks Ken for your help throughout the build. I'm wondering next about pulling my hair out to build a temp waterbed on part of the table for plasma torch and make it a dual head machine. :D

I still haven't hooked the LEDs up as I've just figured out how to get my prox sensors up and running and have a limited amount of wires left (6 in total, incl prox sensors.) I'm thinking I can get all my prox sensors to run using existing ground, existing +24v to each estop, plus 3 wires, then 3 wires left for LEDs. Then for Z home button I'd need 1 more wire, so just figuring that out at the moment. The LED idea is for them to flash thrice per sec when in estop mode, or cycle pause, and when in go mode, to flash to step data.

The one thing I feel very lucky about is the tolerance of my machine throughout. It's very tight, very accurate, and so it was worth all the "Redos", re-cuts, heat straightening for weeks etc to get that level of precision. If you are building one yourself, accept no less than perfection on the Gantry square, rail cutting, and Y car welding and you will have a precision machine.

Working on some cool designs now, so will post them when I cut them, stay tuned!
Chris

You are most welcome. Just doing my part for the community.
You don't need screen cable for the proximity sensor, it runs on 24V so more tolerant to interference. The best part is its very low current, you can use any wires you can get off home depot or grocery shop.
As for the water bed, you don't have to get too elaborate, you can try things out with a huge baking tray or any kind of shallow trays with at least 76mm depth, fill it with 50mm of water & put it on the table. You can improvise the slats, nothing fancy, they are sacrificial support best made out of metal. BTW, don't forget to protect your table top from water & spark.

Cool thanks! I'll try it out as soon as I get a plasma torch!

Lets see some logos !!! :) !!!

Logos should be coming this week. I've just been busy cutting is all!!!
Super fun machine! Anyone ever use a shopvac for a dust collector? I think I'm going to do that for now, cough!

http://s16.postimg.org/4wl1wicqt/IMG_0433.jpg
windows 7 screen shot

Nicely done, nice detailing....well done !!
Attention to detail....his a common "noun" among MechMate-guys !!

Vacuuming.....
In my opinion....base on...say a few yrs as a woodworker......Shopvac is better then .....well....noting :p !!
But you'll quickly notice it is truly meet for....the garage !

A fitted dust foot with a minimal dust collector ( say 2hp - +/- 600 cfm) is what you should consider.
Although. MDF is notorious for making dust....vs "wood chips" :eek:

Lot's of fun & "curves" ahead when entering the "great" world of CNC-ing !!
Robert ;)