has anyone here succesfully made a machine with 4 or more axis? just wondering about my current comerical router table for possible retrofit.

Hello,
I have heard of people adding a rotary table on it's side for a 4th axis. Is this what you had in mind?

David B.

Hi,

I added an 8" rotary table as an A-axis to my router for handling rotary work, it's the 6th axis to be added to this router, but only upto 5 axes operate at any one time. There's a picture at http://www.rainnea.com/cnc_5axis.htm
and a video clip at
http://www.rainnea.com/MOV01123.MPG

Regards,

Rab

Hey rab I love your machine. I want to build a 6 axis some day down the road but mosty because I want to build the machine. Does that make sense? I have a design in mind and was curious if you made your 4th and 5th axis head yourself. If so what are the inch dimensions? I'm not too good on the mm conversions. I gues I am just too lazy to do the math.

turmite

The 4th and 5th axis head unit was made from some surplus satelite positioning units of approx 4" diameter. There's some close-up pictures in the photo section here;
http://groups.yahoo.com/group/CNC_Toolkit/
The units are made by Globe Motors and the motor code is 409A582 rated at 12V. A quick Google search will bring up some links.
I removed the brake and tach sensor and replaced them with a US Digital encoder disc and pickup and drive them with Gecko 340 servo controllers. I had to make up some differential transmitter /
receiver circuits for the encoders as they were picking up noise over the cable run. (see http://www.geckodrive.com and
http://www.usdigital.com )
The units have a flange that I machined off and I mounted them at 90 degrees to each other using some 8mm aluminium angle (this bracket should probably be beefed up)
There is an amount of backlash in these units, some more than others, but then they are very cheap. The motor / encoder assembly is quite long and sticks out beyond the unit a bit too much. You also need quite a bit extra clearance to allow the tool to rotate and your work area will be smaller than for an equivalent size 3-axis machine.
If I could find a low weight / low backlash / reasonable cost, etc.
alternative then I `d use that. I used a Sherline CNC-ready rotary unit for the 5th axis on my Taig
mill, but these are too heavy for the router. An alternative set-up
with timing belts and pullies could be constructed. I'm also looking at some parallel kinematics design ideas for tilting the tool angle as an alternative to rotary units.
I can quickly change out the Z-axis on my router from the 4/5 axis
unit to just a simple, but larger router if I'm doing a job that only
requires 3-axes, or indeed a vinyl cutting knife.

Regards,

Rab

Hi Rab
awesome machine there Rab I am interested in learning more about the cnc_toolkit and have requested entrance to your yahoo group, I have a 4 axis router and assume it can be utilized for this setup, I have never used a 4th axis for anything other than indexing because of programing limitations. I have read some of the post and it seems quite complicated but hopefully with some help and lots of effort I can learn to manipulate it.

Don't be put off using your 4th axis, it isn't as complicated as it might first appear and I'll try to help you through any problems,

Rab

thanks all for your input. i really want to make my own machine for the garage. and my boss was interested in a 4th and 5th axis head retrofit for are commerical machine(router). i hadnt really thought that far ahead. hey Rab i was wondering how rugged that 8020 aluminum is that i see your using .....like whats the toughest stuff you can cut. i really want a machine that can cut steel(light cuts) just wondering? i was going to weld a frame up out of 3" square tubing. mill style, not gantry. any suggestions would be appericated.

Thanks

this forum Rocks:D

Hey Rab. Thank you for all you input. I have this idea in my head of building a really small 6 axis with the total footprint not being over about 15"X15"by as high as necessary to get everything to work. Made of machined aluminum with precision ball screws and minature thk profiled ways and bearings. I want a tiny dc motor to use for the spindle and the drive motors will be size 11 steppers. I want to build the machine just for fun mainly but I though it would be a great way to take to the local schools to interest the kids in machine work and cnc in particular. I would primarly use it for cutting wax and maybe soft metal as in gold or silver. Feasible??

turmite

Rab,
I downloaded the video clip. Good stuff!!!!
I like it.....very impressive!

Klox

sdwilson

I've cut 12mm aluminium plate with my router, but only taking 0.5mm deep cuts at a time.
I've cut steel on my Taig mill using a cheap wood router, a small end mill and very shallow cuts.
So, what you have in mind may be possible for light cuts.

Rab
http://www.rainnea.com/cnc.htm

turmite,

bear in mind that you lose a lot of useable work area when doing full 5-axis cutting, imagine when your tool is horizontal and rotating to approach your workpiece around 360 degrees for a worse case scenario,

Rab

this is what i had in mind. thanks rab thats quite the machine you got there. i got a few questions for you .....

1. materials you made it out of?
2. how much did it cost?
3. can i have a peek at the plans?( i want to build out of steel)

thanks man

oh yeah i wanna join your google group!

sdwilson,

1. Mainly Aluminium extrusions

2. Very difficult to say as most parts were bought surplus

3. I don't have plans as such, but i do have a 3D model

there's a few plans and kits around for 3-axis routers and mills or you could get a cheap surplus machine with blown controls, it would then be a case of adding the rotating axes.

Rab

thanks rab.

im shopping around right now .....got a few bills to catch up (fresh out of school...again)

Rab,

The motors you bought were 409A582 motors. Did you just buy the motors or did you also buy the Turntable assembly? The turntable assembly looks to only provide one axis of rotation. Would two of these turntable assemblies work?


Bill

Yes, I bought the motor / turntable assemblies,
two of these units are mounted at right-angles
watch out for the backlash on them,

Rab

I must applaud your inventiveness. I have another brief question. You mention that you use a servo controller for these motors. Are your other axis also servo driven? They look like Steppers.

It's just the 4th/5th axis head that's servo controlled, the rest are steppers.

Rab

RAB,
Loved the movies!!!
Got any more????
This stuff is cool.
I'm planning now...
Jamie

Really nice machine Rab. Very impressive.

I felt like I won the lottery when I just got my fourth axis mods done to my 4 head router.

I have a seldom used 8' x 12' router that has a ton of clearance in the framework and over 36" of (potential) clearance available in the z axis.. I have had some mild fantasies about turning it into a 5 axis ( or more) machine to do full size sculpture with. Right now I do my large work in 12" slabs, laminate and finish with chisels.

Colombo now offers a commercial 5 axis conversion spindle that is very nice. I have not priced it yet, don't want to ruin the fantasy.

Again, nice machine, Thanks for sharing, Phill

Hello all.
I have a set of globe rotary table units and am in the process of getting the flanges removed and a "T" bracket made up to make a 4th and fifth axis.
This motor are rated at 12VDC, and a 340 gecko as a voltage range of 18vdc to 80vdc. I found this link http://www.futurebots.com/parts.htm that says the motors seems to work from a voltage range of 6vdc to 24vdc.
My question is what voltage do I use to design a powers supply. Do I run the motor at 18vdc and accept the short life of the motor. Or do I underpower the gecko drive.
Any help would be appreciated.

P

Hey guys - I'm in the process of making a 4th axis - SO. maybe a little help on this 2 year old thread.
I've looked to find a simple way to figure out what the gear is - Hmm - gotta buy lots and find one that fits - or maybe someone has been down this track already.
The images will show my challenge -- how to stick the gear on the shaft! Was considering using J B Weld - but seems too permanent. I'd like to buy the right one - but the pitch angle and source - is the bother. I count 20 teeth, and major diameter is 17mm?
TIA - Jim

I would really like to see rab's machine but I can't get to the link

Really nice machine Rab. Very impressive.

I felt like I won the lottery when I just got my fourth axis mods done to my 4 head router.

I have a seldom used 8' x 12' router that has a ton of clearance in the framework and over 36" of (potential) clearance available in the z axis.. I have had some mild fantasies about turning it into a 5 axis ( or more) machine to do full size sculpture with. Right now I do my large work in 12" slabs, laminate and finish with chisels.

Colombo now offers a commercial 5 axis conversion spindle that is very nice. I have not priced it yet, don't want to ruin the fantasy.

Again, nice machine, Thanks for sharing, Phill

Nice work, I love that traditional carving, I used to make alot of queen ann legs for chairs.
Question: adding that 4th axis; can you give me a play by play on that.
and the scanner looks like alot of fun, who is from?

Very nice machine. Picked up 2 5" rotary tables of ebay for $80. I plan to make a 2 axis head like yours out of them. As for my 4 axis, I plan to mount my 4' record and marples wood lathe in the bed and drive it with a stepper. Who knows if it will work good but the price was correct.
Excelent machine, keep up the good work,
Tim