digitizing a part location

[eloid]

I have this question
Let say you cut outa mdf part... but some time later
you need to made some mods to that part
but... the part is odd shaped and lining it squaredly back up is not
that easy cus the part not square it odd shaped....

Is there a digitizer that you can use run to digitize the known
feature corner etc., them get mach skew you machine file to
fit the part placement... Is there a laser or touch probe
and macro that can do this...

[Ayjay]

I am not sure about a digitizer, but you could use your existing part to cut a pocket of the outside profile in some MDF, (maybe a few thou bigger) and then drop your part in the pocket. That would hold it in place plus provide you with a reference point to machine any mods to the part. Just a thought.

[ger21]

http://www.razordance.co.uk/probe25D.htm

[eloid]

One of the things I always want to do, is reuse old peaces and left over
scraps of wood, the problem is ... the scraps are not square it hard to
place and positions you tool path over the object you want to cut...
The question is, how can you digitize the outer corners of your blank... to your toolpath.. or create more than one referance,to a edge or feature etc...on the blank and move you to toolpath to location and skew it to fit if needed?

[eloid]

http://www.cnczone.com/forums/showth...tizing&page=14

this has a simular idea, but how do skew/rotate your part to the new ref for the tool path to start... if these are your new ref points?

[BobF]

build the zero finder like Ernies. Mark the center of your piece and use Ernies finder set the reference to the center. V-carve can generate referrenced off the center.
I built a combination center finder / corner finder using a combination of Joes and Ernies ideas. Don't know how I got along without it. I use the zero finder for Z as well.

[eloid]

is there a proper name/ term for this kind of set up...
I seen a youtube video of this once...I be dammed now...
I cant find it... it was on a turn key machine, laser system with all the bells

[BobF]

Not sure.
Ernie, Joe, and Greolt have all posted videos on youtube, I think.
There are 3 or 4 threads at least here on the zone. Sorry don't have links for you.

[eloid]

Im still working on my frist build .. but maybe more experiance mach users can maybe answer this question if you where to digitize 2-4 points ie the corners on you work piece can you skew / rotate the tool path to fit that perimeter box to optimize you work piece and reuse other wise scap wood?

[ger21]

It's probably easier to rotate the stock on the machine. But there is a command to rotate the toolpath, but I've never used it. G68 I think??

[eloid]

i guess when you have material thats is a odd shape or has no true edge to ref off or super heavy it very useful. In this eg..you may want to keep that look of a rought edge ie cross slice from tree trunk or a rought edge of a granite counter top... and you want to carve into it....... But you need to skew rotate you toolpath...? it would seam easier to drag you toolpath into your digitized work area.


I seen a video for cncing natural stone , in this case it was impossble to rotate your work... because size and weight of work pcs... In this case there where including and centering a fossil in the design, centering it with in the work piece to the work table....

The concept was ... place it on vacum table digitize it, set your ref
and have the software skew / rotate the toolpath... and just go...
it was a very cool tool

[BobF]

Vectric can set the ref to the center of the part. Probably others too, but this is one I am familiar with.
Draw part with ref set to center. Put any odd shape piece on table and clamp down. Find a spot where there is room to cut part and set ref.