Pulled the Trigger on a PM 45 CNC...

[wquiles]

Seriously guys, I'm asking that you wish me a little luck here... I'm about to cut my first part with the mill using BobCAD/CAM to make the G-code. Two big steps at one time...

Full report later tonight...


Ray

Good luck Ray )

 

[Boswell]

Seriously guys, I'm asking that you wish me a little luck here... I'm about to cut my first part with the mill using BobCAD/CAM to make the G-code. Two big steps at one time...

Full report later tonight...


Ray

Eagerly waiting on your report (and pictures)

 

[jumps4]

good luck Ray )
did I ever show you my 90 degree bent 1/2" endmill from forgetting a decimal point?
the shanks are soft and will bend if they hit the vise really hard lol
steve

 

[Ray C]

Success!

I had some problems getting the machine and part coordinates to agree. Somehow got it figured-out but I'll be darned if I know how I did it.

The stock is 1" square aluminum and the cut was just a 0.8" square cut 1.0" down with rounded off corners on the top 0.75" and two divots that are 0.25" deep and inset 0.125" in.

The dimensions came out about 5 thou undersize. Need to get to the bottom of that.

Not disappointed except for it taking so long to get setup.



Ray

(PS: The shop is well lit but the iPhone camera doesn't adjust exposure very well).

 

[09kevin]

Congratulations on your first cut, Ray! That’s a nice looking setup you have. Is it possible that the end mill you used to cut the profile is oversize? I know some of my high speed end mills are .002/.0025 over size, If you described the end mill inBobCAD at .500 and its actually larger it would cut the profile undersize, I doubt if the end mill is .005 over but it’s something to look at. The only other thing I can think of is the holder could have run out.

Kevin

 

[Ray C]

good luck Ray )
did I ever show you my 90 degree bent 1/2" endmill from forgetting a decimal point?
the shanks are soft and will bend if they hit the vise really hard lol
steve

Hey Steve, did that setup look safe enough? ... Junkiest vise in the shop, with a 5" long piece of aluminum that will push over if it crashes in the X or bend if crashed in the Y.

My max table speeds could be outpaced by a glacier -but somewhat faster than plate tectonics. :impatient:


Ray

 

[Kennyd]

Seriously guys, I'm asking that you wish me a little luck here... I'm about to cut my first part with the mill using BobCAD/CAM to make the G-code. Two big steps at one time...

Full report later tonight...


Ray

Ray, I made my "first cut" with a pencil when I got my new/old CNC'd Bridgy. Sexy it wasn't, but it boosted my confidence a little. Unfortunately life (and my side business) has gotten in the way so I cant devote much time to mastering it anymore.


[video=youtube;9MDKMulAllU]http://www.youtube.com/watch?feature=player_detailpage&v=9MDKMulAllU[/video]

 

[jumps4]

there is nothing wrong with taking it slow
I have my max speed set to 50 ipm still, I'm not doing production
have you used the " set steps per unit " button in the lower left of the settings screen in mach3 to calibrate yet?
also, leave the gibbs slightly loose until the machine settles in, too tight causes excessive backlash caused by torque build up before motion.
I set mine tight and could not hold any accuracy.
also the .005 could be the flex in the material being so tall, the endmill could have sucked the material in.
do not set the backlash compensation in mach3 with the gibbs tight you will get false readings.
If you want me to, I'll explain the way to properly set the gibbs and backlash in your thread or make a short video showing how I learned to do it and post a link?
steve

 

[Ray C]

there is nothing wrong with taking it slow
I have my max speed set to 50 ipm still, I'm not doing production
have you used the " set steps per unit " button in the lower left of the settings screen in mach3 to calibrate yet?
also, leave the gibbs slightly loose until the machine settles in, too tight causes excessive backlash caused by torque build up before motion.
I set mine tight and could not hold any accuracy.
also the .005 could be the flex in the material being so tall, the endmill could have sucked the material in.
do not set the backlash compensation in mach3 with the gibbs tight you will get false readings.
If you want me to, I'll explain the way to properly set the gibbs and backlash in your thread or make a short video showing how I learned to do it and post a link?
steve

50 IPM -You Indy driver you... I'm set at 30.

I really think the issue was material flexing. The top-wise dimensions were good but side dimensions were short. I'm not worried about it right now but yes, I did set the steps per unit and checked it with travel and test indicators. It was dead-on in test conditions.

Yes, by all means, show how to do backlash adjustments etc...

Thanks...
Ray

 

[jumps4]

Ok I'll put together a video showing what I have learned and post a link here when I get it finished.
warning my best friend says my videos put him to sleep and require a lot of coffee to watch
steve