My diy machine

[WoodSpinner]

Hi, I've been building/working on my junkpile cnc. It was built from shop scraps and skate bearings.

Here is a shot of it



I know, not real impressive but its been kinda fun to play with.

Here is an issue I have been experiencing that I could use some input on.
When carving 3d images it leaves a faint waffle pattern in the smooth parts and I'm thinking that pattern is similar to the allthread screws as far as the spacing on them. My guess is that since the tables are so lightweight that they ?shudder? while the screws are spinning leaving the pattern, does this make any sense? if so would adding weight to the top table dampen it at all or do I just have to wait til my steel gantry machine is finished to get this right?

Another question I have is about tool definitions. For instance I have a 2flute router bit that measures almost exactly .25" but the slot it cuts is around .26 wide, I have runout on the spindle of approxamately .006" so do I leave the definition at .25, or should I go with the .26 like the slots its cutting? or do I do something else entirely?


John

[ger21]

We get our bits resharpened, and always cut a slot to get the actual tool diameter. Although this is a slightly different situation, I'd still use the slot width.

[ger21]

How'd those router clamps get in your junkpile?

[kevin swan]

Hey that does the job COOL i love it

[WoodSpinner]

Originally Posted by ger21 How'd those router clamps get in your junkpile?

You spotted that did you. My original z axis was an oak board with angle iron on the sides and a plywood box holding the skate bearings and plywood router mount.

In an attempt to slowly move to a more decent machine I figured I'd start with rebuilding the z axis. I was able to construct this new one from .5" aluminum, 1x3 1/8th" thick box tubing, angle iron and soforth. when it came to the router mount I couldnt get it right so splurged on a k2cnc router mount.

so this is an evelution of the machine, but the y and x builds are on hold until I get more $$$$ for parts.

John

PS, as far as adding weight to the tables, I thought about putting bricks around the cutting area to give it more mass but not sure if that will work or create even worse havoc with the bricks being knocked off the tables durring accelleration. course that would probably eat into my accelleration forcing me to slow the machine down even further, at present I've been cutting at 40ipm and rapids at 80. accelleration for x is 10, for y is 7.

[ssutton]

Great machine Woodspinner! I love it when a man can take what he has available to him and make something useful out of it.

Good luck in your on-going improvements!

Scott

[WoodSpinner]

Originally Posted by ger21 We get our bits resharpened, and always cut a slot to get the actual tool diameter. Although this is a slightly different situation, I'd still use the slot width.

Thats what I was thinking. Thank you for the confirmation.

John

PS, thanks everyone for the compliments Its a wonderful hobby, just glad I dont have to do it for a living

[WoodSpinner]

On occasion I get limit switch triggered messages when nothing is on them, I was going to try adding a capacitor to them, I found I have some 1.uF Tantalum Capacitors, will these do?

John
ps. these are what I have, http://www.radioshack.com/product/in...ductId=2062392 anyone know if the short leg is + or - ?

[Zygoat]

if there are no markings, and the legs are the same length then they are not polarized. meaning you can put them in any way you like.

[WoodSpinner]

Originally Posted by Zygoat if there are no markings, and the legs are the same length then they are not polarized. meaning you can put them in any way you like.

Nope, no markings, but one leg is longer than the other if that helps?

John

[Zygoat]

short leg is negative (-) if they are polarized at all. just go with the short in the neg. (-) side and you will be fine.

[Mountaincraft]

Those are some tiny steppers on the x and y axis... what are they from? They seem a little big for printer steppers... Surprised they are big enough to push that router through anything...

What size are they?