Pull G10's from an external file?

[crazy^millman]

Also I make my fixtures for parts on the machines. I never use vices and I hold with dovetails, or pit bulls, or other methods right to the face of the tombstone. Everything from start to finish is done from center of rotation. The picture is all solids not one surface in there. When I do my set-up sheet and use solid Layout I am done making set-up sheets quickly and easily. there is a method to my madness we have 12 pallets here and we do a lot of repeat jobs so when it is programmed it done around it running for years the same way without having to move from machine to machine. This one got thrown in the mix since we were caught up on other machines. We also program a lot of parts putting them on the center of the table and we also do a lot of 4th axis milling on parts so having 2 methods for doing parts is not practical.

 

Again to each their own, but even in a production environment I always did everything from center of rotation and were always able to hold .001 ture position all day long as well. Even do some .000 true positions with only .001 of bonus from max material condition.

[specv]

I am sorry but I cannot share the Macro on here as I did not come up with it, I will just say that its a very easy trig calculation that calculates a new offset for x,y,z at any angle.

[specv]

I agree with verndog, I will say I am not opposed to C/L programming but I don't see the benefit.

 

I can make a macro that calculates the part zero from machine zero and have exactly what you guys are talking about. If i use multiple work offsets anyway like SAIPEM said then there is no difference in our programs except for my number match the print.

[Joe788]

I agree with Specv 100%, and ALL I do is horizontal programming.

 

I'm still programming from centerline, because all of the offsets are calculated from the center of rotation. The benefit is that the numbers make sense to somebody looking at it (which is usually me, 2 years down the road). The face of the part is Z0., instead of Z12.0328, etc.

 

Occasionally I will make parts that are 100% centerline origin, like Saipem and Ron are advocating, but that's only when it's one single part in a technigrip on the center of the table.

[Verndog]

quote:

---

Again to each their own, but even in a production environment I always did everything from center of rotation and

were always able to hold .001 ture position all day long

as well. Even do some .000 true positions with only .001 of bonus from max material condition.

---

So how many re-posts did it take to get the true pos. .001 or 0?? Or are you saying your tooling is always within .0001 and all machines have zero backlash not to mention cutter variance since you have no more then .0005 possible error in any single axis to hold that tolerance?

 

Sorry but Nobody can ALWAYS hold that kind of tolerance unless they always cut 1/2 thick alum. 6.0 long with brand new machines...try again.

[Dave.L]

I don't have horizontal experience but I saw this once upon a time and though it may be useful, maybe not. I think this is related to what you guys are talking about. Take a look:

 

http://www.cncci.com/products/Fixture%20of...0calculator.htm

 

EDIT: Sorry guys, I just notice someone else posted to this site. Sorry.

[iowajim62]

Ron,

Glad that was an easy solution for ya.

You get used to new machines with 300 offsets and probes and forget about variables used to stetch things out.

 

Verndog,

So many variables; shop temp,machine backlash and wear,pallets in and out,operator part loading errors etc....

.0005 won't work either cuz one of the other axis is gonna take away from that so you gotta have like .0002 jes messin

 

holdin .003 would be great with all the variables thrown in but I've seen that not be achieved as well.....

[Guest SAIPEM]

quote:

---

quote:Once done, the COR numbers don't change unless something catastrophic happens.

 

So would you consider not having that machine or tombstone available catastrophic...how about recutting form jaws cuz they wore over time??

 

quote:Having a known origin to start from is invaluable.

 

Or it can be unnecessary and useless depending on the conditions. [Wink]

 

There is no right or wrong here, you have to look at the build qty, machine availability, importance of shop flexability and about 10 other factors to know what is best for that situation. Using a proven coordinate calculator on the shop floor with a good setup person its tough to beat programming from part zero for versatility in a job shop, and they will not be reliant on programming when they play musical machines or tombstones with parts as short run shops will do.

---

Please.

You can come up with a million reasons to justify anything.

 

If a given method works in your environment, stick with it.

 

Whatever method anyone uses, one thing is for certain.

Documentation of the required setup and all related data is an absolute necessity.

[crazy^millman]

quote:

---

Sorry but Nobody can ALWAYS hold that kind of tolerance unless they always cut 1/2 thick alum. 6.0 long with brand new machines...try again.

---

Sure you can if you know what you are doing and approach things with a good set-up approach and make things the right way the 1st time. Most of our tooling is made from steel so a lot less Thermal expansion to deal with. Machining is machining and if you want to argue semantics then we can do that, but if you see the kind of parts we do you will know I am not full of the brown smelly stuff.

[crazy^millman]

On a different note here is what I ended up doing. I made up a Excel Macro Sheet showing all the Values like so:

 

Like I said before made the program pull everything from the variables since nothing is the same on these fixtures. I even went as far to make a set-up sheet like so:

 

Hopefully that will be enough to allow them to run it lights out like I want without having the operator be there.

 

Thanks for the ideas, suggestion and comments it is nice to have conversations like this.

[Verndog]

quote:

---

even in a production environment I always did everything from center of rotation and were always able to hold .001 ture position all day long as well

---

I dont care how you approach it there are way too many influencing factors that prove in real life your comment is just "generally" wrong.

And you imply that because you program from C/L this is easier to hold, when in fact the opposite is true, (unless you add coordinate offsets to lie to your C/L to allow adjustment for real world variables.)

Yes, it can be held under certain conditions, with certain features, but not "always" or even close in a practical mannor. Please...do not advise any design engineers with such commnets as our jobs are challenging enough with the near impossible true pos ABC .005 crap dimensioning schemes with todays "engineers" that have no clue why it matters if -A- is the end of part profile 100.00" away from the dimensioned hole and the surface length is all of .250 wide...projected 100.00" = how close of angle error allowed??

 

BTW..you better re-do all those fixture offsets and carry them out to 4 place decimals as well if you want to hold true pos .001.

[Dave.L]

quote:

---

hold .001 ture position all day long as well. Even do some .000 true positions with only .001 of bonus from max material condition

---

.000 true position w/ .001 bonus is the same as .001 true position assuming you are at least material condition.

 

And, I bet you are making the parts to least material condition coz I don't think anyone will ever hold .000 true position and I would challenge anyone to measure it with any accuracy.

 

BTW, true position not only calls out location but it also controls perpendicularity and roundness inherently depending on the datum structure. So to hold .001 true position can be very part and feature specific.

 

The datum structure can greatly influence how achievable this is.

 

So, as an example, if you have a .250 dia 1.00 deep, any circle at any depth better be within location of .0005" radially. So, the hole better be on location and very straight, assuming your datum structure includes a plane, which most do.

 

PS, nice looking fixture and layout sheets

[crazy^millman]

quote:

---

Again to each their own, but even in a production environment I always did everything from center of rotation and were always able to hold .001 true position all day long as well.

Even do some .000 true positions with only .001 of bonus from max material condition.

---

Oh and if you are going to quote me do it correclty did not read the past tense in part of that did you??

 

quote:

---

BTW..you better re-do all those fixture offsets and carry them out to 4 place decimals as well if you want to hold true pos .001. [Wink]

---

Vern where did I say I was holding that on this job? I merely pointed out that it possible to hold those tolerances when using center of rotation to run parts with. You simply implied it could not be done using center of rotation. I am saying it can be so who is right who is wrong? Can it be done either way yes. If you have taken the time to make sure everything is dialed in correct and cutting correct and hold everything like it suppose to be you can do some pretty amazing things. You want to not pay attention to things then nothing is possible. You do not know my background, you do not know the type of work I am doing or have done. Now if you want to call my professional into question do a search and see how it lays out.

 

You have 3 bores in line and need to hold .000 true position on the other 2 bores where the bottom is the datum. The next 2 bores have the +.001/-.000 with max material applied to them. So in this case holding that on a bridge port can be done if you know what you are doing. Amazing how so many take something said and think of a something the size of an airplane and think you are applying .000 true position to it. Many things can have .000 true position and if you are again approaching it correctly and make sure your set-up are accurate maybe using ground area to hold part with say ground mating pieces with say $2000 boring head you can really hold those +/-.0002 holes to size and can hold those crazy tolerances, but I guess that is why they call me crazy because I love those types of challenges.

 

Another example you have a valve mounted on the center of the tombstone and are machining from all sides guess what that is programming from the center of rotation, but not according to you guys I would need to abandon that and create 45 offsets for all the different indexes since programming from center line never gives me the accuracy I need to accomplish tight tolerance machining. Hum seems I need to give back some of my contract work then, because I got a couple jobs now and that is how I am approaching it.

 

Again to each their own, but walk a day in my shoes before you go telling me I am full of Sh$t. I got customers on this board and do not really appreciate you insinuating I have no idea what I am talking about.

[crazy^millman]

Dave thank you and yeah many things influence least and max material callouts. Datum structures and there are composite tolerances all come into play when doing any kind of machining. Most times I have seen these callout that are features to them selves and not back to say the outside of a part. It does happen but you normally do not see that to kellered or surface machined part or ever castings.

[Verndog]

quote:

---

You simply implied it could not be done using center of rotation.

---

I never said it could not be done. If fact I said it could here.

 

quote:

---

Yes, it can be held under certain conditions, with certain features, but not "always" or even close in a practical mannor.

---

I called you on your statement that...and in your exact words... but even in a production environment I always did everything from center of rotation and were always able to hold .001 true position all day long as well.

 

Keeping within the context of discussion, we are talking about programming from C/L of rotation on a Horizontal machine. Assuming we are talking about indexes taking place because that is a main benifit of using a Horizontal you say you were ALWAYS able to hold true pos .001 when in fact you propably should have said "on certain occasions" you held TP .001 after you got everything dialed in, and when you did it had nothing to do with programming from C/L of rotation (the discussion)...correct?? What does always mean to you??...How about all day?? Wouldn't that include the first part you made, otherwise why throw that in??

 

And if you ALWAYS are able to hold TP .001 all day then yes you will need to fix those offsets, your own words in plain english told me that you did on that job and every job.

 

Dont mind me though, I usually have prefered to let others show me how great they are rather then tell me. ..Peace...I made my point.

[Zoober]

Verndog, Your point, though it was made, does not make it correct. I do the kind of CL programming you are ranting about every day, very successfully. Horizontal or vertical, doesn't matter.

 

If you do any full 4th or 5th programming, you'll understand not only the benefit of CL programming, but the necessity.

I have done work with Ron, and know his style pretty well. It works.

Would you program a MAM prismatic-ally? I hope not.

Though there is merit in doing some work as faces, it is not very friendly in most complex 4 and 5 axis work, as you have just limited yourself to 3+1 or 3+2 axis machining. For most of our parts, that is not something I am willing to lock myself into.

Making programs operator editable?

That in itself is laughable.

 

Considering most of my programs come in at about 4+ meg, do I really want to expect my setup guy to have to edit that monster?

Programs coming from a cad system should run.

IMO, if you are requiring your operators and setup guys to intervene to make a good part, then you are doing something wrong, and all the offsets in the world will not make it right.

Shoot, our setup guys VERIFY origin and offsets, they dont SET them.

[Dave.L]

quote:

---

Verndog, Your point, though it was made, does not make it correct. I do the kind of CL programming you are ranting about every day, very successfully. Horizontal or vertical, doesn't matter.

---

Maybe I am wrong, but I read Verndog's point to be based on .000 or .001 true position, and I agree with his point regarding this.

[Zoober]

we do .001-.005 true position all day in this manner. Compound angle holes are our business.

Here's a sample of type of stuff we do this way:

 

translucent:

 

[Guest CNC Apps Guy 1]

quote:

---

...never program a horizontal from center of the table ...

---

HERESY!!!

 

Better than 90% of the time I do this. Often each part/position has it's own work offset but they are all coming form the same location, center of rotation for X and Z and Y at the top of the pallet. Also, these locations never change.

 

quote:

---

...the numbers make sense and they match the print...

---

ACK!!!!!! That just encourages programmers to not do their due dilligence in the first place IMHO.

 

MACRO programs are such a pain, so few people know how to use them any more. CAM Systems have taken over for the most part thankfully. I try to minimize the use MACROs now because they are a bear to support. Mostly use them now just for probing and automating machine functions.

 

JM2C

[crazy^millman]

Robert thanks, but some people can only work off what they can do not what others can do. If you take what I say to be a day in day out everyday thing then take it anyway you want. Vern the example I gave you go right over you head. Dave it does not say .000 it says .000 with .001 bonus and yes that is .0003 liner and yes it can be done and yes I have had .000 with .03 bonus and still makes it a stupid call out of zero true position. Pigeon hole your mind all you want. Some of the parts I have made programs for have casting worth $80K so you either get it right or go find another job. Again you want to take a general comment and make it specific then do what you please with it, but telling me because I use center I am always have to re post shows me you have never done it or have never done it right or really do not know how if you we to start calling peoples abilities into question around this place. I got 24 years under my belt and make very very good money there is a reason for that. I got news for you it is not because of my great spelling abilities, correct use of present, past and perfect tense or grammar for that matter.

 

I will be more than glad to list the over 200 different machines I have made programs for ranging from Wire Edms, Swiss Screw Machines, Table-Table 5 axis, Head-Table 5 axis, Head-Head 5 axis, the different 4th axis machines, both vertical and horizontal, 5th axis Mill/Turns, 4 axis dual turret lathes, Y axis lathes, C axis lathes, 2 axis Lathes, and then we can go into all the different manual equipment I have run over the years. We can then go look in my toolbox, sold some stuff like my 0-1,1-2,2-3 and 3-4 anvil thread mics and my pin gage sets, and my .00005 digital Starrett Id Mics and my 6-9 and 9-12 OD Micrometer sets, and other things, but still have enough to go into any shop and work my tools any day. You learn how to square a block by hand to .0005 and achieve a 16 finish by hand went you went to school for machining? Do you know how to hand grind you own tools?

 

I have showed some of my set-up sheets and simple parts we do which BTW those are over 50 RC in this thread dazzle me with the superior parts you are manufacturing.

 

[ 02-27-2010, 06:41 PM: Message edited by: Crazy^Millman ]

[iowajim62]

Zoober,

 

Cool Beans

Plate Stock only or Forging/Casting 2 ?

 

James,

quote:

---

MACRO programs are such a pain, so few people know how to use them any more. CAM Systems have taken over for the most part thankfully. I try to minimize the use MACROs now because they are a bear to support. Mostly use them now just for probing and automating machine functions.

---

Heresy

Flipside of using them is keeping yourself workin when others cannot not as an AE tho

 

Ron,

So you got your setup runnin and kickin out parts ?

[Tim Johnson]

This arguing over location points VS. center points doesn't make much sense. Bottom line is the pallet rotates from a fixed machine point and the parts to be machined are at certain distance and angle from that rotation point. The rest is just mathematics. If the fixturing is solid then who cares where the program zero (or several part zero points) is. It really doesn't matter.

[Zoober]

Jim, those are all made from solid stock. No forgings here.....

Tim, it does make sense, when half the guys looking for setup positions can't do the trig. It is our job to make their job as easy as possible.

[iowajim62]

quote:

---

It really doesn't matter.

---

+1 All the numbers come from the same place.

[crazy^millman]

As long as the part is good and the customer is happy that is really what matters.