It writes!! - Amsterdam, NL

[Fox]

Appreciated as always, ken.
'Problem' is I already have my brake, and the aux controlling it...as well as an a-axis

[Tokamak]

Fox,

Revisiting our conversation about smoothing the V Rail to remove variations I mad a measurement.
Installing a dial indicator to measure the variation of one when I measured + and - .010" (.25mm).

Seems to be worth checking. Easier to check after the Gantry is rolling.

John

[Fox]

Are you referencing to my other topic about preloading the y rails, to compensate for the bending of the tubes due to the weight of the y car ? Or what did you actually measure ?

[Tokamak]

Fox,
Sorry for the confusion. This was referenced to post #159 of my build.

http://www.mechmate.com/forums/showt...?t=2526&page=6

We were discussing the need to sand the X V-Rails with a longer V-Block to reduce variations from the grinding. The dial indicator in the picture is measuring the variation in the rolling height of one V roller as it moves in X. The change in height is due to the inconsistency in the cut of the bevel on the top of the rail.

John

[Fox]

Ah, yes, I see now. I did use the v block !

[Fox]

Hi guys,

I am very close to firing up the beast to make a first cut, but have a quick question:

I have powered up my steppers and jogged the machine for the first time. Already felt great to see it move under own power !

But amongst some other things i need to sort, I noticed that with the motors enabled, but not moving (sitting idle) they make a hissing/stuttering sound, not really loud, but enough to be heard when standing next to the table. Is this normal ? It seems not ok to me, but it's my first CNC so I can't judge. When jogging/moving it seems to diminish/be overhelmed by the other sounds.

I use 86HS9801 motors and leadshine AM882 drives.
I feed them with 71 volt.

[danilom]

Tune the drives to motors by Leadshine software and the RS232 cable provided with drives.

Hissing to some extent is ok. it should not be loud just audible when you get very near the motors.

[Fox]

Ok, I will see into this, I autotuned them by flipping the dipswitch (4 I believe) and thought that might do until now, cause I don't know what I need to do to tune them.... but will look into this.

It is audible, but no loud, but also not only when I put my ear near them. I think from about 2 meters away when there's no sound in the room. In this room I can also hear the relais click in my controlbox, when there's no other sound. (it's empty besides the MM with stone walls)

[Fox]

Hey Guys,

another issue:

My Sicce Nova impeller pump, benchtested perfect, but now struggles to pump the coolant round. It barely makes it, and there's not enough flow left at the end of the lines to keep my spindle happy I am sure. I am using 8mm od (6mm id) Pu tubes. Table is 2x3 meter Z = 80 cm.

So what do you use/should I use ? I would like to try and keep the hose size relatively small ( 20 mm hose would fix the problem maybe, but won't fit in my energy chains i think, and there's the restraint at the spindle anyway with those tiny inlet en outlet of 4 mm. Basically I think I need a higher pressure pump to pump coolant trough the system ?

I'd prefer a submersible pump.

[danilom]

This is overhead chart, your pump is declared at maximum 1.5m where it will pump about 50L an hour "maybe" . Comparing it to my atman 104, 38W pump you need at least the "Extrema" model since its 32W pump. and has a maximum overhead at 2.5m

[Fox]

thanks for your quick help, I think I will even go to their syncra line then, because my line restriction will make the flow considerable less I imagine, I see on alibaba a lot of 75 watt pumps are used at 3000 l/m for the spindles, where they screw a copper inlet restircion of 6 mm on:



So maybe their syncra 3.0 ?

[Tom Ayres]

Fox, I mounted my small cheapy pump right on the y car to avoid running into all of the problems you have stated, I really didn't have space on the energy chain to run a line, it hardly weighs anything, I ran 12v to it so far it works great. I don't know if others have done anything similar or if it will last long but it keeps the spindle very cool.

[Fox]

I contemplated that solution ( still am as a makeshift solution - I am sur ethat woudk work, as I beanctested it with 10 meters line or so )

But in then end I would like to get it off the gantry. Reasons are it's already very heavy in my machine, and cluttered, the slushing etc. Plus I already have everything in place. Just need a different pump now :-(.

What kind of reservoir, spindle, and pump are you running on there, and do you use a radiator ( I try to avoid that, os I do not have it laying around here now; another expense ) ?

I have a 3,2 KW 380 volt spindle btw. So above MM average.

[Duds]

Hey Fox, Stick your pump in a bucket of water and hang it from the ceiling already and make that YouTube video

[Fox]

I promise the video and pics will follow soon but this is not the only thing I need to check before firing the beast up.

But I am less then a week away for sure. EXCITING

[Tom Ayres]

I do have a fan and a radiator also on the gantry. The pump has a reservoir built-in, not very big something like 150 mL or 250 mL

[KenC]

No radiator, just a industrial coolant pump & reservoir as per any lathe & milling colant set up.
I reckon even with its good heat insulation property the long PU tube (8~9m to-and-fro )already dissipated enough heat from the water even without the heat mass of the reservoir.

[Fox]

Hi Tom, yeah I though so, so the in between is ,without extra expense a no go.
@ Ken, good to know, that's what I was aiming for as well with my intended trough e chain setup.

On the hunt for a pump that can be delivered tomorrow or at least before the weekend as we speak.

[Tokamak]

Fox,

Put the pump and reservoir on a table next to the machine at the same height as the spindle. The pump won't waste pressure lifting the water.
Put a thermocouple in the outlet hose of the spindle. A lower flow will allow the water to heat more on the way through the spindle. A higher flow will not heat the water as much on the way through. In either case the water is cooling the spindle.

More flow decreases the outlet water temperature but doesn't necessarily cool any better.

Heat loss (watts * .239) = cal/sec
Flow (GPM * 3784/60) = grams/sec
Water temperature rise= (cal/sec)/(grams/sec)

I play an engineer on TV.

John

[Fox]

Put the pump and reservoir on a table next to the machine at the same height as the spindle. The pump won't waste pressure lifting the water.

That was when it barely made it ;-) when I put it in position it did not make it go round. New pump already ordered !

Put a thermocouple in the outlet hose of the spindle. A lower flow will allow the water to heat more on the way through the spindle. A higher flow will not heat the water as much on the way through. In either case the water is cooling the spindle.

that makes sense, but it was really not flowing enough to cool.

Thanks for the formula's I will run them.

[rischoof]

fox,
had same problem with my pump. do you still have the problem when the complete line is filled with water? I filled the hose wiht coolant with a "trechter" when I closed the end by folding the hose double and close it temporary with a t-rap. if you can place the resorvoir and pomp on a higher postition it should start pomping arround the fluid and get the air out.

[Fox]

Yes, I did a similar thing, but then it barely pumped round, bigger pump is on the way, but will be here somewhere next week. This weekend I hope to test it without spindle but with pen. Will post some progress.

[Fox]

WOHA ... I created a monster ... albeit an intellectual one

[Fox]

Got led on my gantry, mister, traffic light, lasers, Z-brake, got air connections on all legs, plus sockets with 220 volt, all buttons work... basically, I got everything working .... except the spindle (well that runs as well, and I can control RPM etc, but as you know but I have no cooling ( better pump arriving next week) .....

So.... I opted for a pen (flipped the spring - for a cheapskate plotter )

It felt great to see it moving. Need to sort out all kinds of little details, but hey it works !!!

I AM OFF TO A CELEBRATION BEER.

Big thanks to Gerald for the design and to all of you for the advise and support.




Ps.

For an intellectual monster you need:

Brains (Leadshine AM882 drives, CPu5B EdingCNC Ethernet, DX 24 volt (5v ctrl) Relais board, Eding CNC BOB, custom built opto iso sensor interface, DamenCNC mist/coolant bob + Z brake bob)



Muscles ( custom 1000 watt 71 V toroid powersupply, 380V Siemens Micromaster, Meanwell 12 + 24 volt powersupplies, 24V contacters, 32A mainswitch, 16A and 1A circuitbrakers)

[IMMark]

Happy times Fox...congrats!
Mark

[Duds]

Yay! :d

[Alan_c]

Veels geluk! Number time... :-)

[MetalHead]

Congrats !!! That Z-Slide is interesting. Can't wait to see it doing cool stuff. Your beast have logos on it ?

[racedirector]

Congrats! A stealth build, well done. Dust very very soon by the looks.

[Fox]

Thanks guys, no... it has no logos and no paint yet.
Will look for a sign shop an cut some.
First cutting will happen when the new water pump arrives for spindle coolant, should be here coming week.. In the meantime I will use the pen to get settings and files prepared, and grow some confidence