[jnymarkp]

Hi

I am a total newbie into CNC, but have fallen in love with this topic.
So i have been lurking around CNCZone for month now trying to decide on what to build.

I amazed of what people are building in here!
It seems the capabilities are endless.

The primary goal is to be able to machine parts for RC vehicles, e.g. tires, hydraulic parts (valves, pistons. pumps etc.), so i want to be able to work in everything from rubber and wood to aluminium and even steel.

Unfortunately i don't have the tools to do any steel machining, så my plan so far is to build a CNC mill out of MDF. Use this machine to fabricate aluminium parts that can be used in a new machine. And then use this machine to fabricate the things that i want for my hobby.

But for the last weeks i have been stuck and don't now where to go.

So here i go with a few questions just to get me started.

1. What size of stepmotors would be needed to be able to do milling in steel (oz-in / kg-cm)?

2. Can i just build my own drivers running the motors at half step, or should i buy prebuild drivers with microstepping capabilities?

3. What kind of guides should i use?
It seems i can choose from either steel rod, linear rail og supported rail.
I have found some complete sets of supported rails for a 3-axis mill, but are they strong enough for what I wanna do?
Example: cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&item=250533252129

4. What sort of motor is required for the spindel (DC/AC/servo)?
If I also want to be able to use the mill as a lathe (youtube.com/watch?v=7Mqy0CRu5rY).

Please forgive me if im a wrong forum here! (wrong)

Thanks in advance!

Jesper

[universalfab]

Just to get you started, I would recommend you throwing away that idea of building your own cnc from scratch. It's not that great of a idea, no offense. I would recommend you buying a old industrial sized knee mill "which some of these older mills can hold tighter tolerances then these new ones straight from the factory" and retro fitting it with a centroid or ajax controller, or something similiar. I would also only use a precision ground ball screw and for motors here is the specs on a servo that I use on my big mill 110 volt DC at 15 amps. That is what my big mill with servos is equipped with and it runs very smoothly and you can barely hear the motors even running. So in my opinion your going to need to spend anywhere from $1000- $4000 on a mill and $3000-$5000 on the controller and maybe you can throw in the motors all wrapped into that price if your lucky. That is if your looking to do quallity work in steel or stainless steel. If you just want something to make mediocre hobby parts out of wood and aluminum then you can probably get something for like $2000-$6000 brand new no work involved, never spent so little on a brand new machine my self and never plan too. All I see for that price in my opinion is garbage, but to each there own. You will most likely find guys on here telling you that you can go to Harbour Freight and buy some peice of crap for $600.00 and you'll be set up right, thats a pipe dream and you'll wish you never spent a penny on it or even heard the word cnc. This is from my experience that retrofitting a manual mill is the way to go when you not looking to spend $100,000-$200,000 on a brand new mill. And you can come up if done right with a retrofitted mill that can do the same work as those $100,000 mills can.

[CNC602]

I also am very intrested in this topic. I would also like to CNC parts for my RC car. I currently make parts then send them out to be cut. Here is a part that I make... well designed and sent out to a CNC shop to cut.
[IMG][/IMG]
This is a lower center Chassis plate for a RC called the MINI LST.
What would be the best type of CNC machine to cut this?

[jnymarkp]

Hi, thx for your quick replyes

CNC602: I haven't started building yet, but my goal is to build a RC truck with hydraulic crane, and second a excavator (fallen in love with CAT945LC).

Universalfab: I can see your point. But my budget dosn't allow for spending 4-9K$ just on the machine. Also the accuracy do not need to be that high (it's just for RC models and playing around , and finally I can se a lot of fun coming my way while building this thing.
Have seen many builds here on CNCZone and on Youtube, where people have build their machines from scratch, and i'm just blown away about what they can do.
So thats what i want (and need) to do
Just need the basics to be in place first.

I have set up a Ubuntu desktop and installed EMC2, and have been looking at gCAD3D as CAD software.

[universalfab]

I also am very intrested in this topic. I would also like to CNC parts for my RC car. I currently make parts then send them out to be cut. Here is a part that I make... well designed and sent out to a CNC shop to cut.
[IMG][/IMG]
This is a lower center Chassis plate for a RC called the MINI LST.
What would be the best type of CNC machine to cut this?

waterjet or lazer, we have a big lazer gantry system here and if your looking to have a good sized quantity of those made I can give you a good price. Just let me know anything you need and I'm sure we can help you out.