Comments on: CNC Drill Sled

By: Keith Neufeld

Keith Neufeld — Mon, 16 Mar 2009 21:15:11 +0000

Mohamed, I haven’t finished the machine; all of it that’s built is what you see above.

The shaft coupler is what I show and describe in my blog post. The other parts you indicate in your annotations were an idea about how to keep the shaft from moving axially within the frame, and aren’t actually working as desired and have been removed.

By: mohamed

mohamed — Mon, 16 Mar 2009 20:31:07 +0000

thanx for the replay
sorry i am not familier with this mechanical stuff
check the photo

http://img186.imageshack.us/img186/2818/drillplatformfront.png

can u give me the photo of ur machine ???

By: Keith Neufeld

Keith Neufeld — Mon, 16 Mar 2009 19:12:51 +0000

Mohamed, screws from the back side into the thickness on each side of the rod.

By: mohamed

mohamed — Mon, 16 Mar 2009 17:46:16 +0000

check this photo
http://img249.imageshack.us/img249/6279/1002569mid.jpg

By: Keith Neufeld

Keith Neufeld — Mon, 16 Mar 2009 02:21:57 +0000

Mohamed, I’m sorry, but I’m not sure what you’re asking.

By: mohamed

mohamed — Sun, 15 Mar 2009 23:39:01 +0000

how you fixed the guide block which the rod move on it
in the plate the
i trying to build x-axis and y axis to my cnc router machine
and other question how you can calculate the steps of the motor

By: Keith Neufeld

Keith Neufeld — Tue, 28 Aug 2007 18:38:17 +0000

Aryan, the lead screw is available at any (US) hardware store, called all-thread. It’s a piece of rod with threads along its entire length, like a long, headless bolt. Mine cost less than $10 for a three-foot length, which is enough for at least two of my axes.

I use 1/4-20 (1/4″ diameter, 20 threads per inch) because 20 tpi divides nicely into 1000. My circuit boards are laid out in mils (thousandths of an inch), so I want to be able to address 1/1000″ exactly — not a nearby size like 1/800″ or 1/1024″.

Since my motor has 200 steps per revolution, threaded rod with 5 tpi gives me 1000 addressable steps per inch. Any integer multiple of 5 tpi gives me an integer multiple of 1000 steps / inch, so I needed rod with a multiple of 5 tpi.

Of the sizes available at my local hardware store, 1/4-20 was the only multiple of 5 tpi, so it was my choice. That gives me 4000 steps per inch, which is pretty fine-grained control (ignoring backlash and other mechanical shortcomings).

By: aryan

aryan — Tue, 28 Aug 2007 18:16:59 +0000

from where do you get that lead screw i also need it in some other project please let me know in which apparatus i can get that

By: Tom McGuire

Tom McGuire — Tue, 22 May 2007 18:50:24 +0000

What are you doing? Your trying to use the drill rod as a guide. And you’ve got it clamped in two places. I guess your planning to have your alignment perfect. You might find out why they charge $80 for a coupler. Why did you put 4 screws in your nylon blocks. How are you going to align that. Why didn’t you use the couplers instead of the nylon. Is that one of those cheap roto tools with the sloppy bearings.
You know I did some blogs and I never get any comments.