Hoss's G0704

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09-12-2010, 05:46 AM
didado

Quote:

Originally Posted by zerodegreec

Can I ask a question to the fellow BF20 or similar owners? Hoss what kind of results do you get with side milling? when I use any size 2 flute end mill on Alum or brass or mild steel I get wavey results... Is this a limitation to the machine? or can you recomend some things to try to get rid of this?

I have both the BF30 (not the Optimum BF30 but Weis-like BF-30) and the BF20. I've had the BF20 since 2005. (they've been around here in Europe for quite some time) The results you're talking about are normal.

Like Hoss said use a four flute for side millling. Generally I take the side cut and then leave the settings as is and reverse ( not the spindle) the cut so it does a finishing climb milling cut. You'll notice that the cutter has deflected during your first cut because it takes off another couple of hundreds of mm when you move the bed back. Even if you run the cutter back and forth several times side cutting with the same setting it keeps cutting a tiny bit because of deflection. This is not necessarily the result of the machine but for a large part caused by the deflection of the cutter itself. The result is often much better. I also use this trick when I really need accurate dimensions and I'm off some hundreds of mm. Generally, I also use the biggest diameter cutter that fits in my machine for sidecutting. The bigger the cutter, the more rigid it is.

On Aluminum you want flood or at least a generous amount of WD40 to get a relative smooth side cutting finish. Aluminum is sticky and tends to stick to the flutes and get in the way while cutting, resulting in a poor finish. Blowing the chips with air is also a great help. Don't however, expect the finish you get with flycutting. It's going to be somewhat wavy. Just except it to a degree.

David
09-12-2010, 08:18 AM
photomankc

Quote:

Originally Posted by hoss2006

Look forward to your results using EMC, I have been wanting to get into using it as well.
I'm getting tired of Windows these days.
Hoss

It's a little more PC picky than Mach. As I understand it Mach is pretty dependent on just the raw speed of the PC. EMC wants to load a real-time layer that sensitive to the hardware. This PC is going to be fairly marginal. After some reading it seems there is a lot going against it. Built in video only, shared RAM, newer Intel chipset. My jitter is pretty high and above 70IPM you can hear the inconsitancy in the motor. Does alright up to about 65IPM.

I really like the cleaner interface. Mach is a distracting mess to me. EMC seems very straight-forward viewing it.

I'll probably keep an eye out for a surplus system out there that is on the working hardware list in the wiki. You can run quite well on much older hardware with the realtime kernel as long as the motherboard and devices don't hose you up.

Typical Linux stuff though, scattered documentation, some GUI, some text files, some command line stuff and lots of outdated info floating around. I like it though.
09-12-2010, 08:31 AM
hoss2006

I have an EMC2 with Ubuntu live cd in front of me, I've tried it on my laptop just to check it out.
Looks cool, should take it down and try it on the X2, probably be a while before I get a console
built for the G0704 with a good PC.
Played with many versions of Linux years ago but they couldn't even detect my sound cards then,
worked much better this time around.
Definitely be giving it a whirl with the 0704.
Hoss
09-12-2010, 09:59 AM
hoss2006

4 Attachment(s)

The Phase 2 prints are just about ready, maybe later today.
Phase 1 owners will get the update first.
A couple pics below show the ballnut pocket needed in the saddle, I used my RF45
but it doesn't have to be pretty.
Just have at it with a grinder or use an endmill in a drill press and make a bunch
of plunge cuts to get the stock out of the way.
The dimensions are not critical.
The nut and mount clear the underneath of the table by about 1/8 inch so nothing needs done there.
The Y just needs the casting flash cleaned up.
Hoss
09-12-2010, 12:11 PM
hoss2006

Quote:

Originally Posted by didado

I have both the BF30 (not the Optimum BF30 but Weis-like BF-30) and the BF20. I've had the BF20 since 2005. (they've been around here in Europe for quite some time) The results you're talking about are normal.

Like Hoss said use a four flute for side millling. Generally I take the side cut and then leave the settings as is and reverse ( not the spindle) the cut so it does a finishing climb milling cut. You'll notice that the cutter has deflected during your first cut because it takes off another couple of hundreds of mm when you move the bed back. Even if you run the cutter back and forth several times side cutting with the same setting it keeps cutting a tiny bit because of deflection. This is not necessarily the result of the machine but for a large part caused by the deflection of the cutter itself. The result is often much better. I also use this trick when I really need accurate dimensions and I'm off some hundreds of mm. Generally, I also use the biggest diameter cutter that fits in my machine for sidecutting. The bigger the cutter, the more rigid it is.

On Aluminum you want flood or at least a generous amount of WD40 to get a relative smooth side cutting finish. Aluminum is sticky and tends to stick to the flutes and get in the way while cutting, resulting in a poor finish. Blowing the chips with air is also a great help. Don't however, expect the finish you get with flycutting. It's going to be somewhat wavy. Just except it to a degree.

David

Excellent advice, thanks for sharing.
Hoss
09-12-2010, 12:46 PM
diyengineer

Looking goood!! :)
09-12-2010, 01:39 PM
mrcodewiz

Quote:

Originally Posted by hoss2006

...
A couple pics below show the ballnut pocket needed in the saddle, I used my RF45
but it doesn't have to be pretty.
Just have at it with a grinder or use an endmill in a drill press and make a bunch
of plunge cuts to get the stock out of the way.
The dimensions are not critical.
...
Hoss

Just in case anyone was wondering. I had to do something similar to mine and I did it on the X2 so if you have one available, it will fit on the table.
09-12-2010, 03:18 PM
duzallcnc

X ballnut

Hi Hoss,

Are you using the stock retaining method where the two bolts just put pressure against the ballnut mounting block?

Thanks
Sean
09-12-2010, 04:40 PM
duzallcnc

X dimensions may vary

Hi Hoss,

I looked at your dimensions for the X ballscrew mod. I have a G0704 from Grizzly but your measurements would result in interference on my machine. I think the difference may lie in the clearance / height of the space under the table where the X ballnut will reside. My height before milling a pocket for the ballnut is .800 , I am guessing your space may be closer to 1.00
or your Roton nut is smaller than my Thompson which is 1 in sq + the ball return on one side. I compared my measurements to yours and they were the same except that I had the pocket at .260 deep and a small slot to clear the ballscrew. If I remember correctly this gave around .050 clearance between the ballnut and the table. My table has a 3 stamped in the right end. Hope it helps.

Sean

P.S. would you mind to post the Gcode for the oil slots?

Thanks
09-12-2010, 08:24 PM
hoss2006

2 Attachment(s)

Quote:

Originally Posted by duzallcnc

Hi Hoss,

I looked at your dimensions for the X ballscrew mod. I have a G0704 from Grizzly but your measurements would result in interference on my machine. I think the difference may lie in the clearance / height of the space under the table where the X ballnut will reside. My height before milling a pocket for the ballnut is .800 , I am guessing your space may be closer to 1.00
or your Roton nut is smaller than my Thompson which is 1 in sq + the ball return on one side. I compared my measurements to yours and they were the same except that I had the pocket at .260 deep and a small slot to clear the ballscrew. If I remember correctly this gave around .050 clearance between the ballnut and the table. My table has a 3 stamped in the right end. Hope it helps.

Sean

P.S. would you mind to post the Gcode for the oil slots?

Thanks

The Roton nuts are 1 inch square too, with the screws in the original end brackets, I still have about .050 under the nut in the pocket.
One of those variances folks will have to take into account between machines. It's not a critical bit of machining. Thanks for the info.
I can give the dxf for the oil grooves, same for all 4 flats on the saddle,
haven't done the z yet, it'll be different.
The Phase 2 prints are done.
http://www.g0704.com/phase_1_and_2_cnc.html
It's gonna be a good while before I move on to Phase 3,
I want to have some fun just using the mill under CNC for a while first.:)
Need to get it all plumbed for oil and then build a console, a Voight-Kampff machine clone perhaps.:)
Hoss
09-12-2010, 10:21 PM
hoss2006

Quote:

Originally Posted by mrcodewiz

Just in case anyone was wondering. I had to do something similar to mine and I did it on the X2 so if you have one available, it will fit on the table.

Good point.
Probably a lot of us have and X2 to handle some of the work
now that we upgraded to the 0704.
Always nice to have a 2nd machine.:)
Hoss
09-13-2010, 08:44 AM
hoss2006

One more rapid test.
This isn't a baseline test with Mach 3 at the minimum 25000 Hz kernel speed like before.
I ran a cable to a good PC and jumped the kernel speed to 45000 Hz.
With the driver at 1/8 microstepping, 300 IPM came easy with the column still on the table.
Good enough for me.
Here are the electronics used.
570 oz/in Nema 23 Stepper motor, Keling KL6050 driver, 48V.
http://www.g0704.com/G0704_electronics.html
Motor tuning settings - Steps Per 8000, Vel. 300, Accel. 60.
Also shows the motor on the left side of the table as an option.
Hoss

[nomedia="http://www.youtube.com/watch?v=3639EIzUc6w"]YouTube - G0704 Max Realistic Rapid Speed[/nomedia]
09-13-2010, 04:45 PM
tmbg

Hoss,

do your phase2 plans include information on AC bearings for the ballscrews, where to buy them, and prints for bearing blocks and preloading them properly?

If so, how much are the bearings that you're recommending?
09-13-2010, 08:18 PM
hoss2006

Quote:

Originally Posted by tmbg

Hoss,

do your phase2 plans include information on AC bearings for the ballscrews, where to buy them, and prints for bearing blocks and preloading them properly?

If so, how much are the bearings that you're recommending?

Yes to all, the most expensive AC's are for the Z axis at $8.43 for Nachi's.
Hoss
09-14-2010, 01:23 AM
tmbg

Excellent. I placed an order for a g0704 and a
G0602, but they're both backordered. I figure I'll snag the plans from you so
I can keep the wheel reinvention to a minimum. Intending to go with roton screws and oversized balls. I have a Bridgeport clone and an old
Clausing 12x40 lathe so the conversion should be a piece of cake.
09-14-2010, 01:27 AM
mwood3

will the precut stock kit come with the phase 2 plans as well? the link goes to the phase 1 and 2 plans together just didnt spell it out in the stock kit link...
09-14-2010, 03:03 AM
mrcodewiz

Quote:

Originally Posted by hoss2006

One more rapid test.
This isn't a baseline test with Mach 3 at the minimum 25000 Hz kernel speed like before.
I ran a cable to a good PC and jumped the kernel speed to 45000 Hz.
With the driver at 1/8 microstepping, 300 IPM came easy with the column still on the table.
Good enough for me.
Here are the electronics used.
570 oz/in Nema 23 Stepper motor, Keling KL6050 driver, 48V.
http://www.g0704.com/G0704_electronics.html
Motor tuning settings - Steps Per 8000, Vel. 300, Accel. 60.
Also shows the motor on the left side of the table as an option.
Hoss

YouTube - G0704 Max Realistic Rapid Speed

Hoss-

I was looking at your electronics list - on the 'best' setup, what do you get out of the C11G that you don't get from the C10 BOB?
09-14-2010, 04:26 AM
BAR553

Pardon the interuption of a newbie post.
First of all let me add my thanks to HOSS and the rest of you for my growing knowledge. I bought my 704, as a result of the hoggin videos, convinced it will do anything i would need.

Somewhere HOSS I think or someon enearly as smart, said that CNC helps you make consistant parts, but does not make you a machinist. I look forward to adding CNC, but I want to learn how to do thing manually first.

So two dumb questions. Why all the need for speed? If you are not in a production environment and have time, do you need it? Second: I thought I would start with a nice easy project like the spindle wrench that Hoss gave the specs for. How does one cut radii, inside or ouside without CNC....... Rotary table? Any good reffernece material that is "how to" anyone can recommend?

Again thanks for letting me listen to the conversations, maybe one day I can add something useful!
09-14-2010, 04:54 AM
photomankc

Speed is time so the faster it can push through the cuts the less time you spend watching it do stuff which, I imagine, gets old after the intial WOW of seeing it move on it's own wears off. Fast rapids are nice and all and with an 18" table I would like it faster than slower but most of the time is in the cut and as long as the motors can cut to edge of what the machine allows then you are doing well. I think I'll be quite happy if I can get 20IPM to start with (cutting that is). It would make a lot of work I do go from an all-day task to something I could finish in a couple hours.

I can tell it wont make me a machinist though. In fact, I feel quite dumb right now trying to wrap my head around CAM.
09-14-2010, 09:05 AM
hoss2006

Quote:

Originally Posted by tmbg

Excellent. I placed an order for a g0704 and a
G0602, but they're both backordered. I figure I'll snag the plans from you so
I can keep the wheel reinvention to a minimum. Intending to go with roton screws and oversized balls. I have a Bridgeport clone and an old
Clausing 12x40 lathe so the conversion should be a piece of cake.

You should have no problems.
My thinkin too is to keep the big equipment manual and CNC the smaller stuff.
Hoss

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