BUILD OR BUY?

[andycorleone]

Hi I need a CNC for milling letters in hardwood and Cutting some 18mm MDF Shapes. I'm thinking in buying somethig in the regions of £800 GBP (about $1500 USD)

But also was thinking in build something like this


but was not so sure where to star?

I know is posible to buy the Aluminium profiles in places like this:

http://www.aluframesystems.co.uk/

but can't find plans to do the project

any help is plans or Cost or Material would be apreciated.


Someone is selling a CNC With a Proxxon NG5/E



I think this splindler router is underpower for my needs what do you think?

[russeller]

where are you located ?



http://indianapolis.craigslist.org/tls/784009892.html

[savita]

can you tell about the X-Y-Z travels you require?
how much spindle power is required for your aplication?

k w kelkar

[savita]

in India

[andycorleone]

Hi, I live in the UK

The travels I need are about

12 inches

24 inches

forthe deep I don't think I will use a material deepper than 2 inches

I regullary will use 18mm MDF and hardwood (OAK) for sign lettering

[Lemo]

Whatever you do, invest into a good Dust Collector. 1HP should be good enough. You cannot use a regular vacuum as the motors do not last.
If you run MDF without a good dust collector.... you will either die soon or ruin your machine and your shop. MDF is very very bad for the lungs.
Lemo

[ab4td]

If you are facing a build or buy decision - you will need to know the requirements you
have You need a 12"x24"x2 cutting envelope with a routing/engraving tool.
I have seen packages from small individuals in the states go for less than $1500 (790 pounds).
To build one yourself should take less than 40 hours build time, and a lot of delays ordering parts, and designing. The control system can be bought as a kit including 3
NEMA 23 (minimum 240 oz/in), drivers, and power supplies for less than $400.
The mechanical parts cost vary greatly depending upon the design parameters you choose. The drive mechanism you choose and the guide rails you pick will affect
accuracy. Gear Racks are least expensive, Lead Screws are more accurate, Rolled ball screws more accurate yet, and ground ball screws are the high end.
Lead Screws should be adequate. You can drive these with timing pulleys and belts,
the more common being the XL series (.2" pitch) in .375" widths.
You must have some form of guide rails. There are lots of variations here depending
upon the rigidity needed to handle the side loads and pressures of the cutting device.
Cylindrical guide rails are often used, with either busings or linear bearings, or simpy
ball bearing rollers as guides. Chromed rails would wear better and elimnate the need
for any rust resistant coatings that might cause dust to stick on the surface.
In this environment, mdf dust would collect on any oiled surface.

I would recommend using a Bosch Rotozip type device for the routing. They have an
speed selection and are a little more durable than Dremels.

There are "plan" packages for a suitable X-Y Router table that would make the process of designing and implementing much simpler. I haven't investigated these, some other member of the group may be able to comment on this.
You will need a computer to drive any of these, and software for the computer. There are many options. I am using Mach3, and BobCad. There may be less expensive options.
In any case, make sure that your computer interfaces are optically isolated. You do not need surges of any type damaging your parallel port or your computers system.
If you do not have parallel ports in your system, you need to find software control
package that uses usb or add parallel port cards.

If you build this, I don't know if the economics would be sufficient to outweigh the effort
expended for this size of table. I am more interested in building and designing. But I do not have a specific goal for creating end products. I am currently converting a Shoptask Bridge mill to CNC using DC Servo motors and PID controllers. I wlll use that
to create the parts to convert my full size vertical mill to CNC. That should consume
a few months. I have been researching putting together an 4' x 8' table for routing
or plasma cutting.

[bajaru]

Hi,
I haven't ordered my plans yet, but I will shortly. After a fair bit of research, I think I will go with the plans at Rockcliff Machine ( http://www.rockcliffmachine.com/kits.htm ). The main reason is because they seem to offer a lot of education along with a variety of plans. I think they also offer a money back garantee which takes the risk out of it. For $20 USD, it appears to be a great deal. Anyway, you might want to check out their designs.

Anyone have any experience with Rockcliff? Other recommendations for plans? (There are several on eBay - just search on "CNC router plans." It's tough to tell from their adverts because they all say they're the best, etc.)

-Bajaru

[andycorleone]

thank so much for the replies:

I just thinkig, with this kind of materials:







doesn't look extremely hard to do something like this:


I just need a few plans of steps from someone who made one before

[Lemo]

Do not underestimate the building process. The simpler the design looks, the more it relies on precision. I build a large router and was a tad surprised how long it actually took. And right now... if I have to drill and tap another hole I'll throw up. The rewards are great, but the cost is TIME. A LOT of it. And if you are pressed to produce something, go buy. A router in your size will probably cost a few hundred more than the parts you have to buy. That considering you have ALL the tools. Or the calculation can go into the bin quickly. In the end, and to be honest... I did not save a thing compared to a commercial router. Mine is just 5 times stronger, I know what I build and how everything functions, and every part can be replaced easily as I know what I did and what my intentions were. And again, do not forget to calculate a few hundred pounds/bucks/euros for tooling and dust collection.
good luck and do not trust the plans blindly.
Lemo

[oopz]

Hi !!

If ur up to have a functional machine why dont bye a FiereballCNC v90
u can se it at the ADs above. OR at http://www.probotix.com then also order the stepper motors and the electronic-Kit for the v90.

Then if i was u the rest of the money on a Kress 800 plus an extra card from the probotix guys (for a 4:e axle). Is there still some £ left then also an other stepper motor..

In this way u have things from the both worlds, something that works and the machine to build the next one :-)

that's my cents in the amount of possible ways and solutions

/oopz

[andycorleone]

Originally Posted by oopz Hi !! If ur up to have a functional machine why dont bye a FiereballCNC v90 u can se it at the ADs above. OR at http://www.probotix.com then also order the stepper motors and the electronic-Kit for the v90. Then if i was u the rest of the money on a Kress 800 plus an extra card from the probotix guys (for a 4:e axle). Is there still some £ left then also an other stepper motor.. In this way u have things from the both worlds, something that works and the machine to build the next one :-) that's my cents in the amount of possible ways and solutions /oopz

Only problem for the FiereballCNC is not sure how much TAX and Customs I have to pay when I receive it here in the UK