On Tue, Nov 18, 2014 at 10:32 AM, dave <[email protected]> wrote: > > On 11/18/2014 06:45 AM, Mark Wendt wrote: > > Stuart, > > > > I have no tooling plates in use now. ;-) > > > > Mark > > > > > Hi Mark, > > I don't know if the site is still active but Les Watts used an > interesting compensation > scheme for his router. Something about a cam on a tensioned wire IIRC. > > Being an old curmudgeon ( is that redundant?) I just have to ask what > the precision > of the process is if the bed were perfect? > Maybe I envision the tooling plate incorrectly but why wouldn't one > that was simply > flat do. After all you do have a controllable Z axis. > > Despite claims by various people about resolution to .01 mm or so it > still comes > down to the accuracy and precision of the process. > > On another tangent I wonder about using a polynomial (curve fit) but > with the number of inflections points you have it may be pretty high > order. Linear interp instead of a continuous function may still be best. > This is the kind of thing that starts email wars. ;-) > > Best wishes however you decide to cure the problem. > > Dave >
Dave, If the bed were perfect, I wouldn't need a correction factor for the Z axis. ;-) I need to keep the finished cross-section to + or - .001" at each 1" X station. I'd have to rebuild the machine to use some kind of tooling plate. The "table" is actually my vacuum hold-down. I have no way to "cut" the table flat using the machine itself, unlike a router. The cutting head is made up of two saw blades held at an included angle of 60 degrees, with the "point" of the "V" at the bottom. I've tried to flatten the bed by filing, sanding, etc, but the problem is, I really have no reference to the cutting head. That's how I end up with being 2 or 3 thou low in one area, 3 or 4 thou high in other areas and so on. I've shimmed out the table as best as I can, and this is what I'm left with, so I'd like to correct for the Z using some kind of compensation read into the machine. Be a lot easier to do it once, rather than having to do it each time I create a different G Code file for each different rod and each different section. I like Andy's lincurve idea. I just have to go through all the reading of the suggestions given this morning, and work out how I can apply it to my machine. I think lincurve will probably be the simplest approach. ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
