The rack and pinion idea is awesome. I really like this setup. I wonder if mounting an ASB-18 bracket to the bottom of the base rotate and then attaching an ASB-4, if that would work? I have a project in mind that would require this same sort of linear design and I think the rack and pinion is the way to go. Where did you get the rack?
I went with a more complex solution actually because I wanted to hide the servo completely inside the rotation base and there’s not a lot of room under there. I used ShapeLock (shapelock.com/) to create a custom plastic mount formed to mount on the inside surface of the rotation base which is conical. I then used MicroRAX to create a servo mount attached to this custom ShapeLock piece and spring-loaded the servo so it always provides adequate gear mesh. I’ll post plenty of pictures after the iHobby Expo this weekend were I’ll be unveiling my upgraded marble maze (sites.google.com/site/teamtobor/marble-maze#TOC-Sneak-Peek-of-V2.0:)
I got the rack and gears all from Servocity
servocity.com/html/gear_racks.html
I just posted an update on my Accelerometer Controlled Marble Maze which features a large amount of MicroRAX. Check out the following post to find pictures of the Maze. I’m hoping to add video and a full write-up this weekend.
Hello,
Do you think a setup like that can be precise enough to build a small cutting table ?
Tanks
Eric Nantel
Qc Canada
robots building robots! 8)
Yes for sure.
I have look for many kit of diy cuting table.
That should be the less expensive one 
X and Y with a dremmel !! What do you think?
For a “hobby” router, I’d go with surplus stepper motors, and an inexpensive driver board. You really can’t expect to get the needed precision and repeatability out of R/C servos.
Even the use of a Dremel is questionable. the spindle bearings simply aren’t up to the increased lateral loads required for prolonged routing (milling).
Now if you just want to move a pen and draw things, you can have fun with that!
Alan KM6VV
KM6VV
Do you have any experience building such router ?
I would like to have one but it look expensive to build.
I use solidwork, i don’t know if i can export and use that to cut sheet of plastic… or aluminium, easilly.
Tanks for your advice
I was phoned by a customer who wanted to build an automated RC car tire lathe. I do believe the required accuracy and torque would be within the realm of servos and this equipment. If I only had more time to implement some of these ideas. 
I do have a Not automatic tire lathe.
It can be easily made i think. It need only “X” movement since you need to pass slowly the cuter to the wheel.
Ajustement of the cuter deep is manual.
demonpowerproducts.co.uk/images/C22338.JPG
Don’t need much torque since you need to cut slowly. Need a servo with high resolution i guess.
Yes, I have considerable experience with CNC’d mills, lathes and routers (check out the Sherline CNC link below).
Also check out the CAD_CAM_EDM_DRO list on Yahoo.
I’m sure you can buy the appropriate module for Solidworks and generate Gcode ($$$).
Checkout the various CNC lists for the hobbyists. You can get by on the cheap.
I like machining aluminum and brass, and the occasional steel part. I will also mill a PCB now and then (isolation routing), and sometimes a Delrin or Polycarb part.
A (hobby) tire lathe? I suppose. Travel of cutter in Z axis (ways) would be light, I suppose one might get away with it. X axis (cross feed) loads would require a little bit of torque. I’d still be inclined to do it with NEMA #17 stepper motors instead!
To see what can be done with small stepper motors an a minimal driver, check out the eggbot by Bruce Shapiro!
Edit:
What’s that? Looks like a little R/C servo on the pen lift arm! (a lot of new stuff on site I’ll have to check out!)
Alan KM6VV
They look to use InkScape witch my girlfriend use with her Cricut.
It can export in gcode. Do stepmotor driver use gcode direcly ?
Yes, I see that they’re using InkScape. Sounds like an interesting (free!) package! I’ll have to check it out, although I do have a CAD/CAM package to generate Gcode already.
Stepper motors require “phase” drives, i.e., turning two or four coils on and off in proper sequence to generate a revolving magnetic field.
A “CNC Controller” program like EMC, TurboCNC, EMC2 or Mach 3 (and my own STEP4 program!) do that for you.
Start doing your research, CNC, “Hobby CNC”, “DIY CNC” etc. should keep you busy!
Alan KM6VV
It depends on exactly what you’re hoping to accomplish. The MicroRAX material itself it pretty strong but will deflect with longer lengths of the extrusion. Using enough cross members and brackets you could ensure a rigid table assembly but you’ll need to do some tweaking to make sure the surface is perfectly square and level.
For the linear motion of the arm on my marble maze I use a micro size servo hacked for continuous rotation. This uses a small gear to ride along a rack gear until a limit switch is activated. This setup of course would not work for what you aim to do since there is no position feedback in the system except for when the arm reaches either end of the track. A similar design using motors with encoders might work but I’m not sure if it would provide enough accuracy and resolution for small-scale cutting operations.
I agree with the comments of others on the forum, a CNC router table setup should probably use larger stepper motors instead of small hobby servos. The forces involved with dragging your cutting tool through the material will require more force than hobby servos can reliably provide. Then again if all you want to cut is soft materials like foam and in very shallow passes it just might be possible.
Hi All,
Don’t know if it’s in the right place to post that. But as it can be useful
to do linear movement with Microrax.
r2hobbies.com/eng/proddetail.php?prod=rcps91116_22ymb
It said that i do 6 full rotation… !!!
Eric Nantel
Interesting servo for $29. If the diameter of the spool is known, then the range of linear motion could be calculated. A larger spool could be mounted on the existing one for extended range.
Wanted to share another MicroRAX creation I recently finished. This is an experimental test device I built to measure the tractive force output of individual robot wheels or a complete robot. The device uses an 11lb load cell and LCD readout scavenged from a $20 digital scale bought on eBAY. There really is no limit to what MicroRAX can be used for.
More information available here:
sites.google.com/site/teamtobor/microrax?pli=1#TOC-Tractive-Force-Measurement-Apparatu
Ok All…
I have just done some Microrax parts.
http://farm6.static.flickr.com/5252/5537502067_e77ac849b8_m.jpg
HighRes:
farm6.static.flickr.com/5252/5537502067_e77ac849b8_b.jpg
Thanks a lot! It’s really appreciated.
