Have a look at post 90 Pictures 1 and 2 should answer your question.
Hey Hoss,
I'm totally addicted to this thread! I check it daily. That's never happened before. I did have a question about the 4th axis/lathe attachment you have created. What it the apparatus mounted to? Is it a flat piece of aluminum that replaces the x-y table? Is it mounted to the x-y table itself? Also, is the spindle that you used for the 4th axis/lathe movement stock or did you machine it yourself? I love the progress you are making, keep up the great work.
Steve
Last edited by grasshorse; 06-11-2007 at 03:29 PM.
Have a look at post 90 Pictures 1 and 2 should answer your question.
Haha, it did. I'm an idiot.
Steve
Thanks guys for the kudos,
Went down and played some more today.
Tried some OD engraving with the 4th Axis.
Took a little tweaking with the motor tuning to get it to cut the
correct height but think i have it down now.
The example below is supposed to have 1/2 tall letters, and it does now.
I had my A Axis motor set at 2880 steps per rev which gave it 1 rev at the chuck or 1.0 in travel. 1/2 = 180 deg, 1/4 = 90 deg etc.
After some trial and error with a wood dowel, the 1/2 in letters were taking up 180 degrees of the stock.
To get it actually 1/2 tall I take the circumference of the part and divided that into 2880 to give me the new steps per rev for the motor tuning.
For the part below .92 dia x 3.14 = 2.888. Divided 2880 by 2.888 = 997.2 for the motor tuning.
Seems to work OK for my set up.
I use Deskengrave to make the gcode. It's free.
To trick the mill to use it for the A Axis, I opened the file with notepad, used "replace" to replace all the Y's with A's and saved the changes.
now it rotates the A axis for the vertical lines instead of the Y axis. tada.
probably an easier way out there and i'll look for it eventually.
just havin fun playin and learnin now.
Hoss
The video will be up soon at youtube.
Hey Hoss, any update on the extended x&y you were working on?
dropride,
the main parts i needed are expected today from UPS.
I still have to order some longer ballscrew on payday.
Be a couple weeks before it gets rolling.
Found another cheap source for the ballscrew at Reid Supply.
Too cool. Love the 4th axis.
It's definitely on my list of things to do when I get my conversion kit for x3.
Should I let the cat out of the bag, I guess so.
Here's a couple pics showing 20 inches of X-Axis travel. Does something look familiar?
Still a ways to go.
Have to fit the ballscrew, remount the motor and make a tooling plate.
Then on to the Y-Axis.
heehee.
Hoss
http://www.hossmachine.com
aye, that I did. Arrgh.
Sorry, watchin pirates of the Caribbean.
16 inches of solid travel, 20 pushing it.
ataxy,
If you measure the x and z dovetails, you can see that it will require some massaging. Not too much though.
Fitting the same ballscrew is going to be close without doing too much harm.
switching to a smaller diameter screw would be easier, but that would be more money.
Will find out how flat the back is ground compared to the dovetail, may need a resurfacing to true it up. Looks pretty good though.
Have to get to making a belt conversion soon. Stripped the low gear out yesterday. oops.
Last edited by hoss2006; 06-17-2007 at 06:19 AM.
well soon you will end up with a x2 the size of a knee mill
wow, so how are u gonna mount the ballscrew, where is the screw gonna go without removing lots of material from the new x axis? i guess ill just have to see it!
liek i said before u should get one of these: http://www.littlemachineshop.com/pro...ory=1687114045
or take some design q's from it and build your own. its soooooooooooooo much bettter than the gears, and u can transmit so much more power!
You got that right.
Actually I'll have 4 more inches of Y travel than the Bridgeports at work when I'm finished. gonna be a bit more work for that though.
Skmetal7,
Don't want to weaken the new X axis at the dovetail so the material came
out of the saddle. The 5/8 ballscrew is gonna be tight, 3/8 would have been easier to deal with. too late now.
if it cracks, back to the drawing board and spend more money.
Last edited by hoss2006; 06-19-2007 at 11:18 AM.
Hoss,
I noticed you are using the same method as I have been for programming the g-code for your rotary axis (find and replace all Ys for As). I'm having a problem because every time it makes an arc move (G2/G3) it goes completely off course. I think it has to do with the I and J values but I don't know if there is a setting in Mach to fix this. Have you changed something that makes it work for you?
Nice work on the extended axis by the way
Hey Hoss
I had a question. I am a newbie to this stuff, and I am trying to figure it all out. I see that you have a DRO with scales on your machine. Does your DRO transmit data to Mach 3, or does Mach 3 compute it's own DRO based on the steppers number of revolutions per inch?
Thanks!
Steve
longrat,
I haven't tried using G2 or G3 yet with the a axis so can't help ya there.
Grasshorse,
The DRO is a standalone unit. I installed it before going CNC for manual use.
I hardly use it at all anymore, maybe just to verify Mach 3 or set it to Zeros when I start a cut in case Mach 3 messes up or something crashes.Then I can get back to the start position.
The new X Axis ballscrew fits now. I'm left with about 1/8 inch clearance.
Need to make ANOTHER bracket now to tie it all together. Fun Fun Fun.
Later Hoss
how in the heck are u gonna extend the y axis? are u gonna make your own dovetail and bolt it on? (maybe it has something to do with the bolt pattern he asked for...)
i guess he will by extending the head foward but i am interested in seeing the amount of flex it will create in this machine as he extend and stretch the axis like he does