5-axis self build?

[DAB_Design]

Mike, what type of experience? I've ran 5 axis machines for almost 10 years, and still currently run one.

Shoot away with the questions, and I'll try my best to muck them up.

[turmite]

Hey Dustin,
Knowing you like I do I am tempted to take this off forum but I have looked so hard to find some 5 axis info lets leave it here and maybe everyone can benefit.

First I want you to know I am not nuts. I want to build two 5 axis machines! I want to build a really small one but I also want to build a fairly large envelope machine too. Like the starter of this thread I want to carve car parts or full bucks from foam or mdf. Nothing any harder than that. Due to the size of the parts I need this thing to move right now! With that in mind it needs to be light weight and stiff. So how do I do it? Ok enough of the emoticons!

What I am after is a machine that can carry a spindle that will handle as large a bit as possible and still be nimble. I plan to use good linear ways with belt drive for the x,y and z. I am curious if a stepper will give enough holding torque to keep a 4th and 5th axis in place while machining mdf at 3-500 ipm?
I will machine it faster than that if I can come up with all the right compontents.

I would like to build the b/c rotary and yoke out of aluminum honeycomb and carbon fiber for stiffness and the ligthness. Do you think this will work? If so co you have any pics of a yoke head that I could get some specs from?

Mike

ps on the small machine, I am certain the composite I described will work. I just need to design that little yoke thingy!

[skippy]

Mike, by the sound of things it seems like you are hoping to build a machine and get seriously into carving other people's projects? i.e. more than just to carve your own present automotive project? I know you've probably already thought this through but if it's just for your project wouldn't it be cheaper to get someone to carve your job for you? I must say that I was pretty impressed with your idea of a simple 3 axis stepper powered unit where you just change the plane that it is working on. (i.e. left side vertical, top horizontal, etc.) I guess the limitation of your idea and mine (carving each plane and then joining (screwing) the planes together) is that the more rounded or flowing that a project is, the more difficult it would be for this type of machine.

p.s. Has anyone got any idea of what one of those heads from http://www.5-axis.com/ costs? Just curious that all.

[turmite]

Hi Skippy,

I think I can build a light weight machine cheaper than I can have the part machined. I believe there is also a good market for this type thing. The accuracy doesn't have to be what GM or Ford would require because these guys are still going to do a lot of hand work on their buck/plug. Dab would be the one to give an idea of how expensive (hrs) it would take to carve a whole car body, but that is not all the story. The door jambs need to be carved the glass flanges where the sealant rubber will go has to be machined. Of course all those things would require additional time but would be much simpler for the machine than an individual having to do it all by hand.

Mike

edited to add: I haven't given up the idea of the manually indexable z axis. The problem with it though is that when you need to cut the door jambs it may not work. The undercuts on the rear of the car would not be possible and probably lots of other areas I haven't even thought of.

[mikejkd]

Turmite,

I am thinking 3-500 inches/minute to be allot faster then is possible for a light weight machine. I am in the process of making a 4x4x4 machine to do scale work right know and the I will move up to the big boy. I will probable use the same x head and drive on the big one and just make x and y bigger.
I am thinking of making a large rotary table for the big machine and axe the fifth, but just a thought right know.

Mike

[Evodyne]

Hi guys,

I was browsing through and see that a few posts back the discussion was on harmonic drives. I picked some up last week off of eBay-$200/unit. They were manufactured by Harmonic Drive Technologies. These are 120:1 reduction. I've attached some pics and a drawing from the web site showing their recommended drive-a toothed belt.

Lance

[turmite]

mikejkd you may be correct but I can cut at 300 ipm in foam right now with a much heavier machine than I am considering build plus I plan to use belt drives with this one, which mariss says is faster than screws or r&p.


lance are you selling those harmonic drives? If so lets talk consider one or two of those on that other deal.

Mike

[alexisw]

Hi, I´m in a simililar project like Ernesto. (Sorry for my poor english)
My machine is only on paper for the moment, it´s a big gantry mill (3metersX - 2mY 1m Z) for foam patterns used in lost foam die casting. I think I will need 5 axis, and in this point I´m not sure to go on. This is what I planned at the moment.
Rack and pinion, with 1/4 reduced by timing belts with 5 Nm torque steppers. I´m thinking to put the 5th ahis on the table, to make it easyr, but I,m not sure. Like Ernesto asked, Who has built a cheap and simple 5 axis?
Kind regards from Argentina

I can live with 1mm accurancy.

[alexisw]

check this site, it has a veeeeery large foam mill

[alexisw]

http://www.hsm-modal.com/

[benergy]

just use rotarty table units, the more compact the better, what baffles me is the offset of the router not being directly under the rotating axis in the rienai router, i presume the cad toolpath generators allow for this oddness

[phantomcow2]

I have plans to make my router a 5 axis.
Yes you can get two rotary tables, but that fun is that? My idea is fairly compact. It should be rock solid too.
50mm preloaded roller bearings, two of them for each rotary axis.

I have some 40mm angular contact bearings I will be using to add another rotary axis anyways. Tricky part I see is coping with backlash

[Khalid]

So whats up guys? where are your build Log? Everybody here start thread with DIY 5-axis and the thread moves with few posts/pages and then suddenly stopped and disappear??.. Is that something Alien or UFO type thing..Why somebody here didn't posted the complete build log..

[Haitham]

hello all
Iam new to CNC, and i was thinking that i can use 5 axis CNC in my sculpture work, to make master pieces of our statues, fountains and chandeliers using cnc then to do silcone mold for it for replication.
The products we will have range feom few centimeters to 3 meters high but large products can be divided into smaller part around 60 or 70 cm the collected again.
I need a very accurate machine that can do very fine details and can reach a very smooth surface finish. i know this will take lot of machining time but it is not a problem.
The material we will use for machining the master pieces is light like plastic , light wood or any other light material that can give me the good finish
Is it possible that i can build a 5 axis cnc, are there any good plans that i can buy so i can start doing it with the help of some engineers
i intend to buy all components so i can get better quality rather than doing them so any one can guide how to start

[cabnet636]

check this

http://www.doughtydrive.com/Plans.html

jim

[Haitham]

thanks for ur reply jim
do u know anyone constructed this machine from doughny so i can be sure about the performance in fine details and surface finish
thanks

[cabnet636]

they have a forum check out the site

jim