5-axis self build?

[Ernesto]

Hello to you all.

I’m new in the group. I’m from Portugal and I’ve been caught by the “CNC virus”...

I intend to make large scale car models in foam. A starting point, to make very accurate 1/3 scale car models in fibreglass.

I bought a couple of months ago, a little CNC machine from Roland. It’s a MDX20 model, and it has 200x150x65mm working volume. Very small, but very accurate machine. I’m going to use it to make the small items for the model cars, like the head lights, the mirrors, the wheels, etc. It’s capable of milling hard wood, plaster, plastic, aluminium, etc. It’s also capable of 3D digitizing…

But I’m with the problem of the body. Especially by the size of it. I was considering many options, including a spectacular (for me) “enlarging machine” that I’ve invented.

With that, I could start with a 1/24 or 1/18 scale model and then I could make an enlarged model in foam (6 to 8 times bigger than the original) by a mechanical device, with out any electric or electronic device (except for the spindle motor).
This is a very time consuming machine, because it couldn’t work by itself.

The result it’s a not very accurate model, especially because all movements are enlarged 6 to 8 times, including all the errors and the smallest details…
But it’s a good starting point to make the models in 1/3 scale (about 1,5 mt length)

But the main reason of this post is that, after I found this group, and a couple of related links (about home made CNC machines), my thoughts went to build a CNC machine that could make my models in foam, but very much accurate and with other scales also.

My questions are, if anyone can take his time for it, and having in mind that I don’t know almost anything about electronic devices:

Can I actually build a 4 or 5 axis CNC Machine?
How much would the cost be?
Are there any plans or kits to start from?

Can anyone tell me how can I achieve that?

Thanks in advance for the time.

Best regards from Portugal,
Ernesto Freitas

[JFettig]

you might be interested in this:

http://www.rainnea.com/cnc_5axisMill.htm there is a gantry too.

Jon

[chuckknigh]

I intend to make large scale car models in foam. A starting point, to make very accurate 1/3 scale car models in fibreglass. Can I actually build a 4 or 5 axis CNC Machine? How much would the cost be? Are there any plans or kits to start from?

This sounds like a very enjoyable project. Welcome, Ernesto, to the group!

Let's take your questions, one at a time.

Of course you can build a 4 or 5 axis CNC machine -- trust me, anyone can do it. How much of the project *you* do will help to determine your final cost.

Let me make the following suggestion. It's often suggested that someone build a small, simple machine first, as a learning experience. You could build a large 3 axis machine, and add the additional rotational axes later, as you gain experience.

The cost is going to be highly variable. Assuming this machine would be used only to cut foam, the loads on the parts would not be very great.

You'll have to tell us what level of accuracy you want, but it should be very possible to make a medium to large sized machine, from commonly available parts, and to do so relatively inexpensively.

If you want to upgrade your parts (for example, manufactured linear rails, rather than something homemade) it'll cost more.

As for existing plans, there are quite a few sets of them, some of which are offered by people on this board. I'll let them respond to this question, specifically.

If you give us some more details about your requirements (what does "very accurate 1/3 scale car models" actually mean, in terms of dimensional errors? +-1mm, or +-1um?) and some more details on the project, I'm sure we can come up with some specifics!

-- Chuck Knight

[HuFlungDung]

One of the big hurdles to overcome is the cost of the 5 axis cadcam software. If I were in your shoes, Ernesto, I would shop around and see if there is 5 axis software within your budget.

[Ernesto]

Thanks for your reply.

In fact +-1mm is more then acceptable.

I can make (or have someone to make it for me) almost all the “mechanical” and structural parts. I only have to get the electronic stuff and learn how to build it up all together…

Of course there is the software problem, but let’s forget that for this moment.

Best regards from Portugal.
Ernesto Freitas

[Ernesto]

JFETTIG,

Was that build by any plans? I'm just in love by the 5-Axis Gantry Router. It's a dream come true.

Ernesto

[Graham S]

You don't need 5 axis, I bet you can do many things you wish with 4 axis or with fixtures, especially in foam.

I made a 5th axis for my mill, had no time to really try it yet, it is also for foam. Check out my site and you will see I make model planes. I also made a digitizer to help copying models etc.

Ernesto, he built it from scratch no plans, the 4th/5th axis are surplus satalite dish turners, the rest is standard router. He uses his own kit of macros in a 3D program I forget the name of. You can get the toolkit from him and join the yahoo group, there is also a free version of the 3D package called gmax, it is limited but you can import from other programs etc.

Cheers,

Graham

[Ernesto]

Can you please tell me you site?

Ernesto

[Graham S]

ooops

www.indoor.flyer.co.uk/5thaxis.htm

[Patrick2by4]

In the rainea site, he incorporates two pancake type axises in order to make his birotational head on his z-axis. Where can these items be purchased? or if there is a kit to build it, where would you purchase it?

I would imagine that if he machined it himself, he must have incorporated two stepper motors in the head.(one to control the A axis and one to control the B axis) They would have to be small and use small internal gearing in the pancake-like housing. From the picture, I can see a stepper motor on the head but only one from the angle shown.

[marvinstov]

Patrick,

http://surpluscenter.com/item.asp?U...atname=electric

Marv

[marvinstov]

Well, looks like they have discontinued the item. Try this.

http://cgi.ebay.co.uk/ws/eBayISAPI....item=3826181817