Well, it made it's first cuts here at my shop. 3" circular pocket, .3" deep, .1" depth per pass, 15" p/minute. I have a lot of things to work out yet, it cut under size by a few thousandths of an inch, I need to tune my axis settings a bit further.

The EM is a Garr carbide 4 flute 1/2", and I am just running a pocketing wizard in mach3 for testing.

Here is a short, poor resolution video in windows media format. I know it is unimpressive, but I am just glad it is finally working.

http://www.rollmeover.com/bronco_fab/bridgeport/video/Bport_cnc_2nd_cut.wmv

Later,
Jason

You're right, crappy video, but having a CNC Bridgeport to play with is too cool for words.

Congrats!

Oh yeah, :flipoff2:

Niice, Very Niice

Looks good , is that what you do for a living retrofitting machine tools ?
If not you most have a pretty good understanding of it to do what you did to that ole girl .

Steve

Nice job Jason! now, if I couldonly find a manual machine for me. That fancy shmancy CNC stuff is too complicated for a bear of little brain like me, but I do like making chips!

PT

No, I work in a chemical plant making chemicals "professionally" This B'port was a pretty long road on the rebuild/retrofit, but not too bad. It still needs a bit of work, but the stuff left can be handled manually for now.

And Pt, I think it was you in my other thread who wanted to know what the total cost was going to end up at. I have just under $2k in it total right now, and that includes a ER series collet chuck and set of 11 ER collets to get me started on tool holders. The ER chuck and collets were almost $300 by themselves.

Later,
Jason

Awesome :) Now make something spiffy.

Nice job Jason! now, if I couldonly find a manual machine for me. That fancy shmancy CNC stuff is too complicated for a bear of little brain like me, but I do like making chips!

PT

PT my buddies Dad owns a Tool & Die shop and he knows his shit as far as what machines need to get back up to par. Back to the point though, he will buy and rebuild machines if and when they have downtime, currently there is a cold saw in the corner (drool). Therefore he has the hookup's on getting good used equipment. If you want to, PM me what your looking for and what you want to spend and I'll pass it on. :smokin:

Congrats! I got mine going but I think I have a servo driver going south. Have you measured (or adjusted) backlash yet? Mach will also deal with backlash if need be. Could you be losing steps? You're running steppers IIRC?

Andy

Looks like mine.

my bridgeport (http://www.cnczone.com/forums/showthread.php?t=24314)

Word of advice, crank the knee up all the way and keep the quill retracted. It is much more rigid that way and easier on the machine. I've had mine running for about a year or so now.

Have fun

Matt

Congrats! I got mine going but I think I have a servo driver going south. Have you measured (or adjusted) backlash yet? Mach will also deal with backlash if need be. Could you be losing steps? You're running steppers IIRC?

Andy

Andy, I haven't had time to do any formal testing on the axis'. I set my motor tuning via the math alone, no fine tuning yet. I only had 1 day off work, we are working a bunch of overtime right now, covering an open shift. As time allows, I will fine tune it. the undersize pockets are not a backlash problem. They are almost certainly a tuning or pulse train problem. My error does not stay the same, but increases in a magnitude of ~.003" for every inch of cut. So, a one inch pocket is .003" under size, a 2" is about .007" under, and a 3" was .009" under. Backlash cannot cause an increasing error. I have talked at length to some very knowledgeable people, and it sounds like I might be losing direction steps once in a while. There are a couple of reasons for this, and I have to check them out. For one, my drivers come preset to read the rising edge of the pulse, Mach likes the drivers to read the falling edge. The drivers could be missing the start of the direction pulse, and then reading it after the first step is made in the previous direction. I have to open my drivers to change the setting, and I need to talk to Keling before I do so, as the drivers have a tamper seal on the seams. There are alternatives I can try by manipulating the software, and I will try that first as time allows.

Be very cautious about using backlash compensation. It is really only intended for drilling and boring, and enabling it during regular cnc cutting can cause some serious issues, as well as slow the machine down to a crawl. Even if it works during normal cutting, it will likely not be able to cure the problem.


Word of advice, crank the knee up all the way and keep the quill retracted. It is much more rigid that way and easier on the machine. I've had mine running for about a year or so now.


I saw yours when I started this project. Looks good. I agree that having the quill retracted further is a good plan, but this was just for testing, and I got tired of cranking the 1500Lb knee up. My air regulator for the knee assist is shot, and that is one heavy bitch to crank on your own. Mine is a series 2 and the machine weighs nearly twice as much as the series 1. The ram is a rigid ram on mine and has a very beefy quill and housing. I doubt that there is much of any problem with running it where I had it.

Later,
Jason

Lookin good, now make me some cool shit for my rig :flipoff2:

Wear in the ballscrews could account for it, but that would be pretty weird unless the PO only ran one part for 15 years on it. Mine's running a hundred roadrunners right now, it seems to be running pretty well! Fun stuff! What's going to be the first real part you make with it?

Andy

Yeah, I agree, but like you say, it is pretty unlikely.

My first part is hopefully going to be a wind chime that a guy on another board kindly gave me the g-code for. It is a tuning fork type design, and it sound really cool. I am thinking I will make it and give it to SWMBO for mothers day, and hopefully get my ass out of the dog house for spending so much time in the shop over the last 2 months.

After that, I have a bracket I promised a guy at work that I would machine, and if that goes well I have all sorts of odds and ends on the back burner. :)

Later,
Jason