[Newbie] Trying to understand how to fix this issue.

This is a rabbit hole with no bottom. In order to allow movement of the table, knee, quill etc., there must be a certain amount of clearance (slop). This clearance allows a small amount of shifting under cutting loads. The vertical mill gets its versatility at the expense of rigidity. If you expect to achieve "perfection" with a vertical mill, you will drive yourself mad. Get a jig borer and a surface grinder, then you can chase perfection in tenths (or less). A very large part of being a good machinist is recognizing the limitations of your equipment and the requirements of the job. How close is close enough? A good friend once told me "There is no clean, only cleaner." The same applies to perfection.
 
turningwheels said:
I have a new Grizzly G0619. I have been having fun with it and now that the fun is turning into an obsession, I am trying to figure out what I am doing wrong. So here's the story. I bought an Accusize 2" Facing tool with 3 cutters. When putting a block of aluminum in the vise, tapping it down on top of the parallels to make sure its sitting tight, I then run the facing tool down the X-Axis of the table. Doing essentially a half overlap I notice distinct lines running along the surface of the block. They have a discernable ridge about .0055 to .001. Also, after facing both sides of the block, I then measure it and it's out up to .002 longitudinally and about .0015 on the Y-Axis.
A little history on my obsession with this issue, I have put a dial indicator in the chuck and checked the table on both x and y axis. X is out less than .0005 across the length of the table. Y is almost perfect, less than .0005. The vise is out about .001 on the X- Axis and less than that on the y-axis. Its a big ole 6 inch vise that weighs about 40 lbs I would guess.
So, the photo is using a 3/4 HSS TIN end mill, NOT the facing tool. I faced the other side to get it as flat as possible on the Y-axis to see if the ridges went away and they did. The side you are looking at is the orientation that is was in in the mill. I forgot to lock the Z-Axis down until I got just past the .6150 mark. You can see the swirls where is changed the depth a little.

I am wondering how I can rectify these weird differences in the facing. Any help is much appreciated.View attachment 327878
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Turning wheels,
Have you seen this video?
Mikey knows what he is talking about, as always.
 
I read that the writer had indicated the table both ways, but noting was said about TRAMMING the table. Also, when trying to hold parts like that in a vise, I use VISE HOLD DOWNS to keep the part snug against the vise or parallels; Starrett and others make them.
 
Janderso said:
Turning wheels,
Have you seen this video?
Mikey knows what he is talking about, as always.
Click to expand...

Tony makes the most entertaining videos. He has a wonderful, if quirky, sense of humor. And he is a good teacher.
Thanks. I had not seen this video before.
 
Well, you guys are right, I was trying to get perfection out of a roughing tool. I had to step back and think about what I was trying to achieve. Which is easily rectified right now with a sheet of 1000 grit sandpaper and light oil. I did learn how to square a block and qualify it to within a .001. Thanks to @mikey, i'm a pro now. I also learned how to lay out cutting a notch for a basic v block for holding round stock and centering it. All in all, I am super appreciative of all of your help and willingness to get me out of the rabbit hole and enjoy learning new things again. IMG_20200621_210329.jpgIMG_20200621_210347.jpg
 
We all begin this way, one step at a time. In just a short while you'll be up and running, designing and making things that you cannot imagine today. Good for you!
 
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