Complete CNC Newb! Please reccomend DIY project!

[dustin1706]

Hey all,

Love this site, read tons of threads, first post.

Sorry to make yet another newb thread, but I seem to become somewhat confounded after reading conflicting info across dozens and dozens of threads.

I would like to get into CNC as a hobby, and as a tool to increase productivity for my other hobbies. Mainly automotive and radio control toys. I will probably practise using the software by making signs, coasters, all that sort of thing.

My initial goal is to construct a CNC machine at 12"x12"x3" at a minimum, capable of cutting wood, plastic (Plexiglass), and hopefully be able to cut thin aluminum, or at least lightly engrave aluminum for marking switch panels etc. Once I learn to use this machine and software, I may build or purchase a larger unit for doing some serious metalwork.

I have tons of tools from hand tools to powertools, welders, plasma cutter, tablesaw etc etc. No real "precision" tools though. I am mechanically inclined, a petroleum engineer by trade, but live in small town Canada, so all my parts will be ordered online. A precise parts list is important. Based on my reading, I think an MDF constructed machine, perhaps reinforced with aluminum, should be sufficient? I will buy a decent set of electronics, rather than scavenging motors or steppers from printers etc. I don't really have a set budget, but I would imagine that a machine like this with decent electronics and decent accuracy shouldn't go over 1k?

Considering my situation, can you guys reccomend a good machine for me to build? Also, a good reasonably priced software.

Thanks!!!

[psp_ngheo]

hi mate

im from australia and im also a newb
currently im starting on my first cnc project
aiming to cut/carve/engrave a bit of wood, metal
plastic...etc

so far i have spent around $250 australian $$$ (australian n canadian dollar should be about the same)
3 stepper motors n a control board (plus MACH3 software) i bought of ebay
the rest of the parts i have scavenge around my dads wasteland
as for the program i receive MACH3 software along with the control board i bought of EBAY
there are plenty of free cnc software u can download for FREE like Kcam, MACH2, MACH3..etc

and so far everything has work fine
so all in all spending aorund $300 should be a pretty good starting price
to start of your cnc project before u go professional

anyway all the best wishes on ur project
and welcome to the cnc comunity
HAPPY NEW YEAR

[TommieK]

Hello Dustin and welcome to the cnc zone. There is nothing wrong with the JGRO. First off, the plans are free! Second, if you are an amateur woodworker, you probably have enough scrap pieces lying around in your shop to build the main structures. Third, if you've read through all the threads, it's easy to see how many upgrades you could do (upsize the machine, change the leadscrews and anti-backlash nuts, more powerful motors, to name a few). Not to mentiion (or am I?) after you have built and learned from the JGRO, you could strip all the expensive hardware to put back to use on you own creation. Tom

[Grovian]

Dustin

Where abouts are you located, i see your in Alberta, i am as well! and just starting a JGRO build

[ilya]

Dustin, welcome to the Zone.

I think that 1k$ is very close to what you'll spend for the machine you're aiming at. I suggest that you don't buy cheap motors and controller - it's a waste of money. You'd better be on the "quality" side - then you'll be able to use your electronic parts for a new and more powerful machine (believe me, there's no such thing as enough power from DIY CNC machine ) You'll probably end up with ACME screws, I doubt that ballscrews will fit in the budget.

Now, I'd suggest that you use Gecko G540 stepping driver. It's the best value for money you can find. The steppers are available from Keling Inc and are not terribly expensive.

As for particular design, there're plenty of free plans floating around. Just keep in mid that the machine won't be able to adequately cut materials that are harder than those the machine is build from. That is, don't expect a wooden frame machine to cut steel or aluminum (you might be able to make light cuts in alu, but depending on the rigidity and cutting conditions you may lack precision).

It will really help if you have an access to the CAD program. Then you can model the machine and set up a pretty accurate BOM.

And be careful - CNC is addictive!

My CNC machine plans at www.8020CNC.com

[dustin1706]

Originally Posted by Grovian Dustin Where abouts are you located, i see your in Alberta, i am as well! and just starting a JGRO build

I'm about 200 km East of you down hwy 14.


I think I will give this JGRO a try and see what happens. Guess I will do some reading in the JRGO forum to decide what kind of equipment to use for the screws.

[dustin1706]

Originally Posted by Grovian Dustin Where abouts are you located, i see your in Alberta, i am as well! and just starting a JGRO build

I'm about 200 km East of you down hwy 14. Which set of plans are you using for your build? any idea what kind of screws you are going to use?


I think I will give this JGRO a try and see what happens. Guess I will do some reading in the JRGO forum to decide what kind of equipment to use for the screws.



Thanks for the help!

[dustin1706]

Did some serious reading on the JGRO. Decided to go with it and just go with the sizes in the plans to make things simple.

I ordered:
gecko 540
48v 7A P/S
3 Nema23 380oz steppers
Limit switches
anti backlash nuts w/ flanges
couplers
bearings

I am going with 1/2" - 10 Acme for everything for now.

I'll probabaly use 3/4 MDF for everything and screw it all together instead of tapping it and using bolts... Tapping MDF kinda sounds... a bit weird...

I probably have enough spare parts to put ogether a dedicated PC for it, Pentium4 2-4 GB ram etc.
I think I'm a bit overkill on the electronics, but like ilya says, I can use these on a bigger machine when I decide to build one.

Can anybody think of anything I'm missing? or any suggestions?

Hey Grovian, are you planning on using acme screws? Have you found anywhere locally to buy them instead of paying shiping and risking damage?

[stevespo]

I don't think anyone else mentioned it, but you might want to consider "multi-start" Acme screws. They'll require special (matching) nuts, but there are several sources for those.

I don't know what the JGRO design calls for, but with 1/2"-10 5 start you'll move the axis .5" for each turn. 2 start will move .2" inch per turn. You trade speed for resolution, but with 200 steps/inch and 10x multistepping that's probably not an issue.

The multi-start screws will keep the motors operating in the better part of their torque range. Of course, plain old 1/2"-10 will work just fine, but you'll need to spin at much higher RPMs to achieve any speed. This also puts a higher load on the CPU and the pulse timing. Most steppers start to fade around 600-1000 RPM, so I wouldn't expect rapids much more than 100-120 IPM with your machine, using 1/2"-10 single start.

A P4 2GB is plenty, particularly if you're not trying to run Mach at a super-fast pulse rate. I have a 1.7GHz P4 and 60KHz seems quite stable. Keep the machine super clean. A fresh XP install, Mach and not much else. Check the Mach site for more detailed specs.

Steve

[Crevice Reamer]

Hi Dustin. Welcome to the Zone!

You have picked EXCELLENT electronics. You will need a few more things though:

Scroll down the page:

http://crevicereamer.com/Page__57.html

CR.

[dustin1706]

Originally Posted by Crevice Reamer Hi Dustin. Welcome to the Zone! You have picked EXCELLENT electronics. You will need a few more things though: Scroll down the page: http://crevicereamer.com/Page__57.html CR.

Thanks man! That made a good read.

Since I have a thread going already, and everyone is being helpful, Could someone please tell me, or at least point to the right thread, what should I buy for Bits? (or end mills I guess they're called)

I want to do some wood, acrylic, and hopefully some very light/and or very slow aluminum.

I would like some quality bits, especially to try the aluminum. Is there a way to resharpen and remeasure these bits? or are they expendable?

I'm looking at the Hitachi 2 1/4 HP router if that matters.

[Grovian]

Originally Posted by dustin1706 I'll probabaly use 3/4 MDF for everything and screw it all together instead of tapping it and using bolts... Tapping MDF kinda sounds... a bit weird... Hey Grovian, are you planning on using acme screws? Have you found anywhere locally to buy them instead of paying shiping and risking damage?

One thing that i have read is to use 2 or 3 sheets of MDF and "laminate" them together, this will be stiffer and stronger then just 1 piece of 3/4" MDF.

No i have not found and ACME screws locally yet, but i am still searching. Fastech looks like they may have some ACME screws, but that is all i have found so far. I saw that they carry 80/20 Extruded Aluminum, so might keep that in mind for a bigger build after i learn from this one.

The electronics that you have ordered are EXACTLY what i am looking at, thats funny!