Fair enough, but I'd say the same to you SketchUcam is not another CAD system, so the tangent is meaningless. I don't care that SketchUcam can back track SkethUp line-segments back to arcs for generating g-code. The CAD piece is important to me as I'm realigning some things to fit with other components I already have, and I already have more capable CAM software. Quite honestly DXF output from SketchUp is about as useful as STL for anyone trying to modify a design, which is to say crap. Circles/arc don't have dimensions or center points and I've never seen a SketchUp design that was dimensionally accurate. All dimensions are off by fractions of millimeters, which means they are a pain to align in an assembly, as hole patterns don't line up. You end up redrawing them dimensionally accurate and replacing all arcs with fitted arcs and then re-dimensioning them because the are always again fractions of a mm off. In my opinion SketchUp is a great free form design system, but rubbish for detailed mechanical parts or CNC work. To each their own.
Here's how I did my z limit+home switches http://www.openbuilds.com/builds/optical-limit-home-switches.512/ Instead of lock collars I used nuts and drilled+tapped a set screw to lock them in place. It allows me to pretension the threaded rod into place and then lock it there.... seems to help. My bearings are 608 so the nut only touches the inner race. I tried just the nut but it spun loose.
then it is time you upgraded both Sketchup (at least to 8) and SketchuCam (1.1b) because both most definitely DO produce true arcs. You cannot see the arcs in Sketchup because it draws them at straight lines, but the Gcode will contain G03/G02 commands for the arc segments IF! you have not exploded or edited the arcs in such a way that makes Sketchup think they are lines segments. DXF files can be a real export/import problem and I'm never surprised when something goes wacky in them in particular arcs getting converted to polygonals. example I just drew and created Gcode from in Sketchup8 this is a 100mm square with the top right corner rounded off. Code: % (Generated by SketchUcam {1.1c-beta}) (Bit diameter: 3.2mm) (Feed rate: 2000.0mm/min) (Plunge Feed rate: 1500.0mm/min) (Material Thickness: 4.0mm) (Material length: 2500.0mm X width: 1300.0mm) (Overhead Gantry: true) (Retract feed rate NOT limited to plunge feed rate) (Optimization is ON) (www.PhlatBoyz.com) (Davids defaults) G90 G21 G49 G61 M3 S15000 G0 Z5.000 X48.351 Y76.545 G1 Z-5.600 F1500 X151.551 F2000 Y132.684 G17 G3 X151.151 Y138.781 Z-5.600 R47.114 X149.949 Y144.826 Z-5.600 R47.114 X147.968 Y150.662 Z-5.600 R47.114 X145.242 Y156.190 Z-5.600 R47.114 X141.818 Y161.315 Z-5.600 R47.114 X137.754 Y165.948 Z-5.600 R47.114 X133.120 Y170.012 Z-5.600 R47.114 X127.996 Y173.436 Z-5.600 R47.114 X122.468 Y176.162 Z-5.600 R47.114 X116.632 Y178.143 Z-5.600 R47.114 X110.587 Y179.345 Z-5.600 R47.114 X104.490 Y179.745 Z-5.600 R47.114 G1 X48.351 Y76.545 G0 Z5.000 G0 X0 Y0 (home) G0 Z35.560 M05 M30 %
@Gadroc, you may be right, BUT, SketchUp is free! Also, to be honest, for work in foam and wood, the accuracy that you talk about is not needed.
@JustinTime, It is and I understand why people use it… and people get passionate about their tools! I just do more than SketchUCam can do, which btw is AWESOME value. This means Sketchups anemic export capabilities (3D Surfaces or segmented 2d) becomes a major stumbling block. For wood and foam I would agree… but for something like building an OX I'm a little more careful. A small inaccuracy in a plate could lead to HOURS of frustration trying to square up or track down amplified inaccuracies at the cutting tool. Back on topic. My first parts order arrived yesterday, thanks @kram242! I just need to finish up the CAD model to get my cut area where I want it and order the last bits of table support extrusion from misumi and cut the plates (one the aluminum for them arrives.) @The Dude have you worked out how/where to mount the limits for the Z axis. It's tight fit to get things where the Z motion would trigger them.
I am really looking into building OX as I have been looking to build one router for a while now. The plan is to bild with Aluminium, BUT shipping cost from US is a kill. Anybody knows if V-Slot is available in Europe?
I am intresting too building OX and I am also from Eurepe . But I would like to know the cost for the OX 2*4 complete kit with the plates. and an estimation for the shipping will be good..... Indeed it looks awesome machine.
There's a guy in England that is a distributor he is called Robo-Cutter Uk. Go to the openbuild store and check the news that is where the announcement of distributors it. Good luck in your builds!
Just a short note to write that my VPS server is down, the host company (GoDaddy) are onto it but I did not want anybody to think that the website was down for any other reason then the hosting company seems to be having problems with the server. The correct link is www.robocutters.co.uk (when its working again), thanks. Colin.
The website appears to be working fine. For some reason however the link you provided doesn't click through with the ".uk" at the end so it goes nowhere. Adding the .uk at the end in the address bar allows it to connect. www.robocutters.co.uk
Thanks for the info and yes, all working again now (phew!) and URL edited to go to the website as well...
Hey guys. Did anyone try ever to move the whole X axis up and down as Z axis , using two steppers but making the connection of the router more strong because it will stand only at X axis wheels ? Of course this increase the cost of the construction , but do we gain something of it ? More stability let say as more clearance of the height ?. I am asking you because I am going to order materials to construct my own machine and just I had that thought.
Very interesting idea. I use Mach3 as my machine control software and this will only allow for 2 axes to be slaved (such as Y and A for the 2 motors driving the Y axis back and forth). Other machine control software may be different. Check out this build http://openbuilds.com/builds/spunks-cam.522/ Tweakie.
My apologies Colin - I must have been editing my post to add the link at the same time you were making your post. Tweakie.
Well since it was a snow day today (around 18" and counting). I got some more dont on my OX. This thing is really starting to impress me very fun build.
@Mopar32985, looking, my man, looking good. If you think that this is fun wait until you start cutting things you've designed!
@JustinTime , trust me i cant wait. This V-slot is amazing its like an erector set for machines. The more i use it the more im impressed with it
I have never seen these inaccuracies you speak of. Can you give the steps to repeat this effect please?
@David the swarfer, I think he speaks of SketchUp and not SketchUcam. I too, sometimes, encounter inaccuracies in SketchUp. Most of the times it's the results of segmenting arcs and circles but not only there.
Yea the discussion had nothing to do with SketchUCam, it seems to me either SketchUp or possibly just it's export system where they seem to crop up.
Well Here is my first cut it went better than i thought it would. Cant explain how happy this makes me haha