Accuracy

[brian]

Brady thanks for the quick reply.
I installed artcam as it was convinent to use as my designing computer is a good walk away.I will be adding on my shop soon as this is only really a hobby at the moment.It wil save me from moving my dongle around.Then I can squeeze my other computer in my shop.
I want to spent some time learning before hanging out my shingle.
I will delete artcam today!
More "ram" ya say.Hey have you noticed how male that sounds(Ram,Dongle) :-)
Thanks for the info
Brian

[Brady Watson]

Brian,
I do most of my work in the office/studio in Pro and then export an EPS of my vectors along with the SBPs across the network to the shop. I have PW2 installed in the shop & if I have to re-toolpath something, it saves me a trip. Most of the time I am cutting a 2D part...3D parts I still have to run inside to change.

-B

[harryball]

Brian,
.007" is pretty good... but probably tweakable.

Setting the Z square is a big deal to some folks. I square my Z using the Zeroing routine... http://www.talkshopbot.com/forum/mes...tml?1158926563
Technically the Z out of square wouldn't cause your parts to be the wrong size just rhomboids from the side. It does, however, effect the measurement depending on how you measure the part since the sides would have slope to them.

Gantry flex is another issue, one way to "see" the flex is to cut conventional vs. climb and note the differences. Bits can also flex, but the 1/2" shank should reduce that. I don't know how to reduce gantry flex, it's not really been an issue to me so I've had no cause to consider it a problem.

Robert

[brian]

Brady
One day I'll be able to hook my computers together.I don't have the internet in my shop,I'm trying to keep things simple at the moment.I have PW2 but I figured artcam would be a better program to run.I'll reinstall PW2.
Robert
I have an alpha and I assumed they had solved most of those problem in the newer model.As you can see in from above that I'm not pushing it enough to cause gantry flex.

Thanks guys
Brian

[richards]

Brian,
Try this experiment. Cut two identical rectangles with the 0.25-inch cutter at 0.20 depth, 3-ips, just like your post above. However, cut one rectangle with a climb cut and cut the other rectangle with a conventional cut. You may be surprised at the difference in size. The rotation of the cutter pulls the cutter into the cut when going one way and pushes it out of the cut when going the other way. To me, it's like a needle following a groove in an old vinyl record; even though there is significant mass in the arm and in the turn-table, the needle is the part that vibrates. The same basic thing happens with my 60x120 Alpha. Lots of mass in the steel table. Good sturdy X/Y/Z axes. But, it all depends on a little, flexible 1/4-inch cutter that is being spun at a tremendous speed and forced into a cut by a mass probably well over 10,000X its own puny mass. Something has to flex.

If you have a dial indicator handy, turn your machine off, zero the dial indicator with the dial perpendicular to the cutter and then give a few pounds pressure to the side of the cutter opposite the dial indicator. I'm guessing that you'll see a lot more than 0.007 inches deflection.

[harryball]

I'm running a new Alpha as well, there is gantry flex, bit flex and so on, try Mike's test, you might be surprised.

Robert