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View Full Version : The More I CnC.. The more I see I don't know..



ibewgypsie
08-06-2005, 09:19 AM
No, I have mostly used my cnc machine for slotting, drilling radial holes, drilling linear hole patterns. Some light profiling.

Learning 3d modeling creates a whole new panorama of things to learn.

Tool offsets, not important if you just use the program one time, Tool indexing. I started using Z-(0) as the tool table. Now I am using the home position as Z and the lowest position as -4.25 was (0).. problem was the floating bed, I have to consider it as another plane of movement, not a fixed place. This plays heck with Mach3s wizards that are looking for a positive height over work piece.

Tools.. yeah this is a crutch. WHen you lose a endmill if you replace with a different brand all your programs are crap, unless you table shift to compensate.

So, I need to build a tool setup bench with caliper, height guage, and some way of locating the kwik switch collet.

I ain't the sharpest tool in the drawer, but I am real stubborn.

I need, another chinese scale to keep track of bed height. Problem is, it won't live with the coolant so it too... has to be cable drive. and remoted..

Repeatable setup.. that is the key of cnc.. I don't have it yet..

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David Cofer, Of:
Tunnel Hill, North Georgia

Mcgyver
08-06-2005, 09:44 AM
if you haven't seen this one, it looks like it would be good for a bport style cnc mill

http://www.tormach.com/tts_products.htm

usually when i see this stuff its like, ok how do i make this myself, but considering its hardened and ground, their prices seem very reasonable

for scales, check out newall. very cool design imo, i haven't bought one yet but love the idea
http://www.newall.com/LEDs/leds.htm

[This message has been edited by Mcgyver (edited 08-06-2005).]

ibewgypsie
08-06-2005, 10:15 AM
I have about 3-5,000 in tooling.. $50 at a time... That whole system is cheap when you consider that.

The prices there look inline with what it should be. Not sure about the staying concept if they will not be able to be found in a year..

David

mochinist
08-06-2005, 11:17 AM
<font face="Verdana, Arial" size="2">Originally posted by ibewgypsie:
Tool offsets, not important if you just use the program one time, Tool indexing. I started using Z-(0) as the tool table. Now I am using the home position as Z and the lowest position as -4.25 was (0).. problem was the floating bed, I have to consider it as another plane of movement, not a fixed place. This plays heck with Mach3s wizards that are looking for a positive height over work piece.</font>
I use a pretty expensive program at work, but I bet the principles are the same in mach 3, I was taught that the best way to program a part is to always use cutter compensation and to not use part line programming, in other words you program the part using a .500" endmill(for example)the program will out put the code telling the endmill to follow on the outside of the profile(or inside). Now on your cnc control you will input the tool diameter as 0", if you decide that the part is too big you can adjust it by changing the cutter diameter to a negative value, -.002" for example(or .002 if the part is cutting to big) would move the cutter over .001", so if you were cutting a 3" round boss you could adjust the cutter either way so that you actually cut a 3" boss.

I always program with the top of my part being Z 0, this is the way I was taught when I was learning to use fingercam(write G code manually).


<font face="Verdana, Arial" size="2"> Tools.. yeah this is a crutch. WHen you lose a endmill if you replace with a different brand all your programs are crap, unless you table shift to compensate.

So, I need to build a tool setup bench with caliper, height guage, and some way of locating the kwik switch collet.</font>

A .500" or .250" endmill is basically the same no matter what brand you buy, you should only have to reset the height of the tool on the control when you change to a new endmill, I assume you cnc is no different than any others and you must set the tool height offset for all the tools so that they go to the correct depths.



<font face="Verdana, Arial" size="2">Repeatable setup.. that is the key of cnc.. I don't have it yet..</font>
Digital cameras are great for this, if I have a particulary hard setup, I take tons of pictures and save them in the same folder where I have the program stored.

I hope the above makes sense, it would be much easier for me to show you than it is to explain it.