Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: JollyCNCuser on August 30, 2015, 11:22:28 PM

Title: Sqauring the Axis
Post by: JollyCNCuser on August 30, 2015, 11:22:28 PM
Would anyone be able to help me with a small problem i have..

The problem is that both the x and y axis need to be compensated for to make them true and sqaure against a straight edge..

Meaning that when the X Axis travel from the home position for example.. without touching any other axis the X Axis with shift
slightly sideways over a given distance. This is rather undesirable.

Could a knowledgable person tell me how to adjust the software so that it can compensate for this?

Hope i have made myself clear.. i couldnt find anything about this problem through searching through the forum

Cheers
Title: Re: Sqauring the Axis
Post by: JollyCNCuser on August 31, 2015, 12:27:52 AM
Does anyone know how to use the Formula Axis Correction function? i have managed to work that much out.

Its crazy thats theres no live support.. its a matter of sitting here twiddling ones thumbs, waiting for someone to help..

There seems to be bugger all information about the Formula Axis Correction function..

Guess ill take the rest of the day off and maybe even the week depending on if i can get help from this forum.

Title: Re: Sqauring the Axis
Post by: dude1 on August 31, 2015, 01:08:29 AM
being like that to a community forum you will get what.

for a start more info, some pic`s and squire it first. doing it in software will only get you so far, is the X axis squire to the Y axis just sitting there on the right and left side.

also is it calibrated. check all that and post back
Title: Re: Sqauring the Axis
Post by: Tweakie.CNC on August 31, 2015, 02:16:46 AM
Hi JollyCNCuser,

You must consider that we are (for the most part) unpaid volunteers here so please be patient when waiting for a reply to a question posted on the forum.  ;)

I have never had to use formula axis correction so can't offer any help in that direction.

However, if you are having an 'out of squareness' issue then the best solution would be to correct the inaccuracy of your machine. If, for some reason this cannot be done then it may be possible for you to use the Local System Rotate function. If your squareness error is constant then just entering the angle will provide the compensation.

I tackled a changeable or unknown squareness issue using a similar solution http://www.machsupport.com/forum/index.php/topic,22932.0.html

Hope this helps.

Tweakie.
Title: Sqauring the Axis
Post by: JohnHaine on August 31, 2015, 03:50:49 AM
It would also help if you could give a clearer explanation of the problem. 


Sent from my iPad using Tapatalk
Title: Re: Sqauring the Axis
Post by: JollyCNCuser on August 31, 2015, 07:15:06 AM
Ok, ill do my best to explain.... The CNC machine i have built, "gantry" (y axis) and also the X Axis Rails are slightly sqew.

If i jog either the X axis or the Y Axis independenty in a straight line, the line is not true... Meaning that if you use the edge of the table as a guide reference for either X or Y axis to travel along,
the travel of either Axis does not run true to the edge of the table.. 
For example.. If i place my cutter on the home position in the bottom left of the corner of the table (0,0,0) and then use the edge of the table as a reference along the X axis, i would like the cutter to run parallel with the edge of the table.. without deviating in the Y direction.
At the moment i put the cutter in the homing position (bottom left corner, 0,0,0) and then jog the cutter along the X Axis for 300mm and it ends up slightly bias to the right about 3mm i have the same problem with the Y axis also, only the bias numeral is different.
I am not taking apart the machine to fix the issue. Thats crazy.

The most enlightening piece of information i have so far is here..

http://www.cnczone.com/forums/mach-software-artsoft-software-/82179-squaring-x-y-axis-mach-3-a.html

But i am unsure how to write the formula.

Anyone any ideas?

Cheers

Title: Re: Sqauring the Axis
Post by: magicniner on August 31, 2015, 08:50:29 AM
I am not taking apart the machine to fix the issue. Thats crazy.

It's actually sound engineering practice, which I'd firmly recommend, fixing a lash-up is always a good idea ;-)

 - Nick
Title: Re: Sqauring the Axis
Post by: ger21 on August 31, 2015, 10:03:47 AM
So you built a table that's 3mm out of square, and you want Mach3 to compensate?

I know I've posted formulas here before in the past, but I'm on very spotty wifi right now and can't search.

You should be aware that there are some instances where the formulas will not work, which will lead to Mach3 trying to "jump" into position, causing stalling or lost steps. I don't recall exactly when this occurs, but it can make formulas unusable in a lot of cases.
Title: Re: Sqauring the Axis
Post by: JollyCNCuser on August 31, 2015, 06:24:44 PM
So thankyou to everyone for their input, I actually have a clever friend who has shown me how to write for formula.

This is quite clever and compensates for all Axis in all directions.

Yes the table was built out of sqaure. I used materials i had laying around, i apologise for being poor.

Id just like to put a big thankyou acknowledgement out to my friend. Thanks Tyler!

Title: Re: Sqauring the Axis
Post by: BR549 on August 31, 2015, 06:38:24 PM
"Being" POOR has absolutely nothing to do with doing POOR workmanship. Then wanting software to fix your problem. But in this case it worked out for you. You got lucky this time.

(;-) TP



Title: Re: Sqauring the Axis
Post by: beefy on September 01, 2015, 03:58:50 AM
Yes the table was built out of sqaure. I used materials i had laying around, i apologise for being poor.

You ain't the only one who's poor. I built a large part of my plasma table from hot dip galvanised steel I was lucky enough to scrounge from a retaining wall job. I had to weld sections together to give me lengths. A lot of the rest of the table is made from old pieces of steel I'd collected in the past. My two long X axis rails are made of nothing more than 1" angle iron, and the V-rollers that go on them are home made. Despite that I have a table that cuts accurately and squarely. You have to take lengths to build your table accurate and square in the construction stage. What is ridiculous is that you blatantly expect software to fix a messed up build, as thought that is normal. I was thinking about parallelism, perpendicularity, etc from moment one, whereas you obviously just slapped something together, messed it up, and then come out fists flying showing your strong expectation of live support, etc for a low cost piece of software. People normally pay a LOT more money for that type of support.

I'm very happy that you expressed thanks to those that helped you, I wasn't expecting it based on your show of attitude.

Come across a bit less demanding and a bit more chilled out and you may end up with more of the FREE help you get here from people that don't get paid to give it.
Title: Re: Sqauring the Axis
Post by: dude1 on September 01, 2015, 04:04:47 AM
it`s done boy`s let it go