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AndyT
11-19-2008, 02:24 AM
Ok, I'm convinced that having a tabletop CNC router will allow me to cut my own panels and other goodies. Now I just need to know what's the best one for the least amount of money. Or should I build one?

Lewis Simmons
11-19-2008, 03:14 AM
Build one. I'm looking at these websites where you buy the plans and it looks a heck of a lot cheaper to do and it means you know the machine inside out.;)

AndyT
11-19-2008, 03:26 AM
So who has the best plans? Prices? Features I can build in? I have a very powerful roto-tool already with a flexible shaft that I can use.

Lewis Simmons
11-19-2008, 03:29 AM
Well my recommendation would be google. I'm new to it all also but I have been looking at prices recently and I think this is the way to go.

Price will depend on what you want to do in the end, how much cutting area, what to cut. Obviously the greater cutting area, the higher the price but if you wish to cut metals other than aluminium then the price will go up as you have to have some more bits here and there for that.

fweinrebe
11-19-2008, 03:43 AM
I am in the planning phase of building my own CNC. I use the one on this page. http://computer-numerical-control.wpblogspot.com/. The plan is for free. One can also download a SolidWorks 3D plan of the CNC. The SolidWorks viewer can be downloaded for free.

It might be on the smaller side, if you want to do large panels.

AndyT
11-19-2008, 04:14 AM
What about software? Is there a free CNC CAD controller? Or will I have to buy Solidworks or what?

AndyT
11-19-2008, 04:38 AM
This would be very easy to scale up and the roto-tool he uses is almost the same one I have.
http://uk.youtube.com/watch?v=6drMZqmyXQc

fweinrebe
11-19-2008, 04:50 AM
Solidworks is not for free. Except for the reader which is needed to see the plan in 3D.

There is a program call Solid Edge (version 20) which is now owned by Siemens. According to their website the 2D part of their program is for free.

Then you need some CAM software as well for converting the CAD file into G-Code for the CNC Software to work. I am still researching in that area for free software.

Then for the G-code to be executes and the commands send to your controller board, you need software like Mach3 which is free up to 500 G-code commands. For more you need to buy it. There is a free Linux program which does the same as Mach3. It is called EMC2.

Look at this page for the links: http://www.probotix.com/cnc_software/

There is a great value for money supplier of a controller board: http://www.hobbycnc.com. They even have a plan for a CNC as well. (Pitty they don't ship to Namibia)

Then there is another MyCockpit member's site that actually uses the above mentioned controller board and motors. http://www.hoddo.net/cnc.html. Do yourself a favour and look at the videos as well, very inspiring.

fweinrebe
11-19-2008, 05:11 AM
I did this CNC Basics e-course (free) to learn the basics of how CNC works. It helped a lot to understand how to get started and what is needed. It is short and simple.

http://www.cncinformation.com/CNCBlog/cnc-basics-e-course-1-cnc-basics-steps-learn-cnc.

It is compiled by a guy named Ivan Irons which hosts the website: http://www.cncinformation.com.

JW&Partner
11-19-2008, 06:28 AM
Hello,

as we are using several different CNC routers with different software you first have to decide the application you need it for. What kind of material do you want to cut? Depending what material you have to decide weather the machine needs to have linear bearings with ballscrew. I would recommend not to save on tools. There are many suppliers worldwide selling cheap machines you can use for balsacutting etc. It's ok if you don't want to be precice to 0.01mm if you want to engrave etc. You need to have a solid machine. If you have special questions feel free to contact me.

regards Jörg

droddis
11-19-2008, 07:52 AM
There are plenty of good plans available for free, rather than paying. Or you could buy a precut MDF kit. CNCZone forum has loads of plans to download to diy and buildyourcnc.com shows how to build a cnc router with a video diary. They also sell an expandable kit, although its a bit bigger than a desktop size. 2' x 4' routable area but can be increased to 8' x 4'. There are loads of kits on ebay.

If its for making panels then you could also look at laser engraver and cuter. You can pick one up a hobby one on ebay for around $900 - £1500. with a working area of around 200 x 220mm. The laser engraver will give smoother text can cut square inside corners.

Software:

You need a cad drawing program to draw the panels.

A CAM software to convert to G-code - (you can write this yourself in a texteditor but text is complicated.

And a controller for Windows - Mach3(payware) or linux CNC-EMC (freeware)

Hope this helps

AndyT
11-19-2008, 10:06 PM
Is there any freeware for windows?
I saw Mach 3 and I think it has a G-Code converter built into it.
I have Fireworks and Google Sketchup. Can I use them to create the models?

I will be cutting thin aluminum and wood and plastic for panels and making my own PC boards. What else will I need?

BHawthorne
11-20-2008, 12:13 AM
There is linux-cnc for free. I'm going mach3 with my build though. I really would suggest www.cnczone.com. I think of them as the mycockpit.org of cnc building.

fweinrebe
11-20-2008, 02:09 AM
Is there any freeware for windows?
There are some freeware DOS applications as well. TurboCNC. It is normally recommended to take an old PC for your CNC controller software. Because the environment its working in becomes dirty. Therefore that Linux EMC2 options could be a great solution. There is an ISO file available on their website which has the UBUNTU 8 Linux version already packed with EMC2. No compiling needed.

TurboCNC is found here: http://www.dakeng.com/turbo.html



I have Fireworks and Google Sketchup. Can I use them to create the models?
It looks like any program that can save a DXF file (AutoCAD File format) can be used. These CAM programs normally converts from DXF to g-code.



I will be cutting thin aluminum and wood and plastic for panels and making my own PC boards. What else will I need?

You will probably need the 60 degrees tip for the PCB cutting, if you needed finer cutting. Otherwise the 30 degrees tip is used. Available from here: http://www.megauk.com/.

There is some info on the PCB Routing on this page: http://www.brusselsprout.org/PCB-Routing/

BHawthorne
11-20-2008, 03:01 AM
It looks like any program that can save a DXF file (AutoCAD File format) can be used. These CAM programs normally converts from DXF to g-code.

I'm really partial to using Adobe Illustrator's DXF export function. You can do really good font work in Illustrator and convert to outlines in it. If it's something I want to do very fast and is only 2D I don't hesatate to use Illustrator vs. a regular CAD app.

2D: Illustrator -> FeatureCAM -> Mach3
3D: SolidWorks -> FeatureCAM -> Mach3

I realize that those apps are not free, but those are the ones that work best for me. I really suggest them if you can afford to go that route. MasterCAM is also a potential substitution for CAM, but I slightly prefer FeatureCAM's learning curve over MasterCAM. :)

paulj
11-20-2008, 03:44 AM
Hi Guys,
I have a quick question if you don't mind.
I have a Dremmel Multipro tool is this any good for converting into a cnc machine?
I'm thinking that I could just use an engraving bit to do the lettering and a milling bit to cut plastic/wood or light aluminium panels.
An I on the right track here or would I have to start off by buying some other tool?

thanks

Paul

Perik
11-20-2008, 04:48 AM
Hello

Most important to decide is what Jörg at Simparts talks about - what to mill and at what precision.
As soon as you think about metalwork the price of the CNC must and will increase. You can find quite affordable CNC parts on Ebay, but anyway I would have seen a 10 times maybe more increase in cost compared to the unit I have build which is based on purely Home Depot parts except the Stepper kit from www.hobbycnc.com (http://www.hobbycnc.com/)

Have not tried Alu yet - I may be able mill soft metal at shallow depth and at low speed. So far only MDF and Acrylic. The precision is about 0,1mm over 300mm which is good enough for my needs.
The resolution is 1,75mm/200=0,00875mm. Hey, this is some good numbers, but are only achievable by high cost mechanical parts.<O:p</O:p
The size of the mill is also an important factor. I early decided to be able to put the whole MIP in the machine. The CNC had to be “open” in one direction. My working area is about 400x800mm and 150mm in vertical movement.<O:p</O:p
<O:p

About the software:<O:p</O:p
I bought the combined package of Sheetcam & Mach3 from:<O:p</O:p
http://www.sheetcam.com/register.shtml (http://www.sheetcam.com/register.shtml) £150 (UK pounds).<O:p</O:p
I had CorelDraw already in place so the 2D work is OK. Exports in HPGL format from Corel (Corel is handling DXF badly) and into Sheetcam for ToolPath and Gcode – then to Mach3 for milling. Lately added Meshcam (www.meshcam.com (http://www.meshcam.com/)) ($175) to do 2-1/2D milling. For PCB (schematics & layout) I’m using Diptrace (www.diptrace.com (http://www.diptrace.com/)) Free until 250 pads.
Exports in DXF-format to Sheetcam for contour path & gcode, then to Mach.

This is the status at the moment and I'm satisfied with the results so far.
About to finalize the MCP these days.

The whole case is about time & money which are some of the most important factors for all of us.
<O:p</O:p
<O:p</O:p

Happy milling<O:p</O:p

riche543
11-20-2008, 08:42 AM
Heres another link that might help you

http://buildyourcnc.com/latest.aspx im just about to start building this one ,

vcimmino
11-20-2008, 01:15 PM
Well, I think that building a CNC is an hobby itself. You need to learn a lot of mechanics, electronics, other than have many basic tools already available even if you already have some complete plans. If your hobby is the simulation I don't think you'll afford the hard work needed.

Thus said I'm sure that you won't regret in buying one prebuilt, both artigianal or industrial, as you'll spend your time in learning how to use it (that has an it's own long learning curve) instead of becoming mad to make one your own and maybe to discover thereafter that you are not satifacted of it's tollerances.

I think that without spending a fortune you can find an aluminium CNC based on 2A stepper motors like mine, with good strenght to cut and mill plastics, wood and maybe alu itself for around 1500-2000$ ready to use. Then you will have to spend more for softwares depending on the target of your works. Mach3 is an easy and almost cheap choice of software interfacing. You can also give a look at EMC2 that is a linux free software with very good feedback.

To design you can use Illustrator, Corel, Autocad or any other basic 2D drawing tool and then import in a specialized CAM software to create the milling paths (There are a lot around, many already said here, I use Artcam and VisualMill) that EMC2 and/or Mach3 will recognize. If you need to cut real 3D objects then you'll need maybe Rhino or Solidworks or 3DStudio, but be aware that the 3 axis machines can't create all the paths that a true 3D object need to have milled. So you should have a 4th and maybe a 5th axe as well.

To end with, tollerances are important, but hey, don't ever think that any hobbistic CNC will really cut at 0.01mm true resolution. Many factors are crossing themselves in milling centesimal perfect paths. You won't ever made them going all togheter the same way, but for casuality, and If I were in any CNC owner I just would be happy if the cuts are in the 0.05mm range error. That error wouldn't be visible anyway but measuring it.
I would anyway choose a good milling with high torque power (500W>) and high quality bits that will improve the final quality of your work. But you will learn all of this yourself as you'll start working with a CNC machine.

I hope to have given you useful informations. Ask more if you need.

BHawthorne
11-21-2008, 01:49 AM
Well, I think that building a CNC is an hobby itself. You need to learn a lot of mechanics, electronics, other than have many basic tools already available even if you already have some complete plans. If your hobby is the simulation I don't think you'll afford the hard work needed.

I find that CNC and simpits are complimentary hobbies. It's just another tool to be used in further refining your simpit. It really depends upon how you approach simpit building though. Someone people are happy to just put things together once and it's how it is. In that situation it makes more sense to just have someone cut the parts for you. If you're constantly refining things and find that fun though, it would justify a CNC machine. In order to do it right though you will have to drop $1500-2500 on a CNC machine plan/kit and parts. That's a lot better than dropping $7,000 - $15,000 on a turn-key CNC solution though. If you want a router table that'll do all the big shell parts look at the MechMate (free plans) and ShopBot (Turn-key). If you want to cut smaller metal parts for gauges/insturments and electorics boards get a X2 mini mill and CNC retorfit it or get the Seig X2 (turn-key) CNC. There are also cheap mini lathes that'll do your turning work from Harbor Frieght. I don't suggest CNC kit for that. I'd just manually turn the parts on it.

Router Table: MechMate or ShopBot
Mini Mill: Harbor Frieght X2 or Seig X2


but be aware that the 3 axis machines can't create all the paths that a true 3D object need to have milled. So you should have a 4th and maybe a 5th axe as well.
Actually, 3-axis mills can cut 5-axis parts just fine. Since time is not much of a $$$$'s factor in hobby CNC I suggest the person merely reorientate the part in the vise or tooling to be cut in 3-axis. No need to drop a bunch more money on a 4th and 5th axis for your CNC when you can just remount the part your machining in the orientation needed to get it cut in that 4th and 5th axis with the 3 axis setup. Only thing it'll cost you is zeroing in the part X,Y,Z 0 in the new orientation and another seperate G-code for the new cuts. At work we only have 2 4-axis machines, so I am used to doing multiple programs for a part so it could merely be done on a 3 axis with proper tooling. The 4-axis machiens are only used on runs that have time constraints for shipment + are complex parts. You can do 5-axis work just fine on a 3-axis, it just requires the machinist to remount the part in the vise/tooling several times.

fweinrebe
11-21-2008, 01:58 AM
I find that CNC and simpits are complimentary hobbies. It's just another tool to be used in further refining your simpit. It really depends upon how you approach simpit building though.

I agree fully. I am actually puting my sim on hold to build the CNC. But then again I am actually "working" on the sim because when it is done, the CNC will manufacture some higher quality parts for the sim.

Hessel Oosten
11-21-2008, 05:39 AM
See also this thread and the thumbnail pictures I've attached there.
http://www.mycockpit.org/forums/showthread.php?p=67805#post67805
The aliasing effect is caused by the low resolution of the photo, not by the mill :-)
Hessel

fweinrebe
11-21-2008, 05:42 AM
Is there any freeware for windows?
I saw Mach 3 and I think it has a G-Code converter built into it.
I have Fireworks and Google Sketchup. Can I use them to create the models?


With Google SketchUp Pro you can export to DXF. But SketchUp Pro is not free.

BHawthorne
11-21-2008, 05:51 AM
Here are some parts for my router table build. The x/y linear stages are 45" Thomson rails and the linear guide for the z is 24" Thomson rails. I still need to get the leadscrew purchased and machine the motor mounts on the z axis. I have a few Geckodrives and the electorincs needed. Just need to find a power supply to run it all. I've not done research on that yet. Also a few Oriental Motors steppers to drive it all. I'll probably just build the table frame out of 80/20 surplus. Tentatively I'd like to be cutting chips over Christmas holidays. :)

http://img92.imageshack.us/img92/7107/002gl6.jpg

vcimmino
11-21-2008, 01:04 PM
I find that CNC and simpits are complimentary hobbies. It's just another tool to be used in further refining your simpit. It really depends upon how you approach simpit building though. Someone people are happy to just put things together once and it's how it is. In that situation it makes more sense to just have someone cut the parts for you. If you're constantly refining things and find that fun though, it would justify a CNC machine. In order to do it right though you will have to drop $1500-2500 on a CNC machine plan/kit and parts. That's a lot better than dropping $7,000 - $15,000 on a turn-key CNC solution though. If you want a router table that'll do all the big shell parts look at the MechMate (free plans) and ShopBot (Turn-key). If you want to cut smaller metal parts for gauges/insturments and electorics boards get a X2 mini mill and CNC retorfit it or get the Seig X2 (turn-key) CNC. There are also cheap mini lathes that'll do your turning work from Harbor Frieght. I don't suggest CNC kit for that. I'd just manually turn the parts on it.

Router Table: MechMate or ShopBot
Mini Mill: Harbor Frieght X2 or Seig X2


Actually, 3-axis mills can cut 5-axis parts just fine. Since time is not much of a $$$$'s factor in hobby CNC I suggest the person merely reorientate the part in the vise or tooling to be cut in 3-axis. No need to drop a bunch more money on a 4th and 5th axis for your CNC when you can just remount the part your machining in the orientation needed to get it cut in that 4th and 5th axis with the 3 axis setup. Only thing it'll cost you is zeroing in the part X,Y,Z 0 in the new orientation and another seperate G-code for the new cuts. At work we only have 2 4-axis machines, so I am used to doing multiple programs for a part so it could merely be done on a 3 axis with proper tooling. The 4-axis machiens are only used on runs that have time constraints for shipment + are complex parts. You can do 5-axis work just fine on a 3-axis, it just requires the machinist to remount the part in the vise/tooling several times.

I think that you misunderstood me.

What I wanted to tell is that if you don't have the right aknoledge building a CNC might be really time consuming, expensive and frustrating sometimes.
Having a CNC instead is indeed complementary to the simulation and cockpit building, and it's not a "if you buy a CNC machine done, why not buy the panels already made...". It's not the same. I don't think you build yourself the motor of your car because you need a car to go to work, but you learn to drive it and experience let you feel confident with it. The same way learning to use a CNC is something that needs it's time, it's a lot ot trials and errors, but it is for sure enjoyable just as you get your first results.

About the extra axis, I agree that you can rotate the piece etcetera, this is exactly what I do to simulate a 4 or 5 axis on my 3 machine. And you can watch on my blog many results of. But telling it to a person that never used such a machine, that he can just zeroing, turn the piece and go, is reductive. Morover this operation has to be done carefully and it's just for expert people I think, that learned the way to divide the various parts paths the right way, center the new piece side at centesimal precision, carefully choice the piece lockings etc. Machining basics to learn are quite more elementary then the advanced technics you have proposed.

Thus said, anyone with our passion, will benefit a lot from having a CNC at home, and if you can buy it already made for 1500-2000$ as I did is even better, because you'll spend your time in making parts instead of making the machine that will make the parts.

Just my 2c

BHawthorne
11-21-2008, 01:28 PM
My interest in building a cnc is much the same as the simpit building. I think I'd lose something in the process by going turn-key solution for a cnc router. I want to know the inner workings of the machine. I like to tinker with things, so it makes sense to me to build a custom cnc machine. It also helps I had half of my current parts donated to me as used unwanted parts. I might have changed my cnc plans a bit if the x/y linear stages weren't free. Besides, if I really want to cut chips now I just ask my boss for access to an idle VMC at work off the clock. :)

fweinrebe
11-24-2008, 01:29 AM
As with simpit building you get 2 types of builders (And combinations in between). One that buys most of the panels and parts from a vendor and assembles it and another type of builder that builds his own parts for the fun of building. It is the same with a CNC machine. Some people like to build one, while others like to buy one.

That said I think it is up to the individual to decide which route he/she is going. Both routes has their pro's and con's.

I rather pay $700-00 for parts and build the CNC than pay $1500-$2000 to buy a turnkey CNC. Because I love building the machine myself.

AndyT
11-24-2008, 02:07 AM
I want to save as much money as possible, but at the same time, I don't want to spend a log time building it either. I guess I'm looking more for something I can assemble that will save me money and time both.

BHawthorne
11-24-2008, 08:56 AM
I guess I'm looking more for something I can assemble that will save me money and time both.

If there was such a thing I would have already bought it. It's much the same situation in CNC as in simpit building. The information and kits are out there but most are obscure or more expensive than you'd expect. There are cheap ones out there but the table is either too small or the kit is made out of MDF or some other inaccurate materials. The problem is getting something to cut the size you need and accurate on anything from plywood to aluminium. Noone has a kit that is price pointed cheap in that targeted kit. Most of the cheap designs are really just designs. They're sold as plans and never have the cut materials with them. I humored for awhile releasing a kit that might target those needs, but the reality is I've not even finished collecting parts on my build yet, let alone be able to prototype the build and work out bugs on my own build yet. That really precludes me doing anything about such a kit. Once I have my table up and running I might revisit that idea though. My idea of a quality CNC build is one that is large enough and accurate enough to reproduce itself in kit form.

Cheeso
11-29-2008, 07:32 AM
Well,

I think the guys over at LumenLab (http://lumenlab.com/) have a fine offering with either their MicRO or the RoBLOKS RoGR. Good value for money and quality build. Have a read through their forums and don't miss the videos to find out more.

Regards,
Gerhard

riche543
11-29-2008, 09:33 AM
Could you Please PM me Gerhard ,Thanks Riche..

Buddym
01-11-2009, 10:45 AM
I built the BigBear CNC machine for cutting my sim parts that I didn't buy. It was easy to build, and works pretty darn well. It is a hobby grade machine, but that's what this is, a hobby.

The accuracy is good and the table size is just what I need. I get a 14.25" x 10" X and Y with a 1.75" Z axis. It's built from high density plastic so it's easy to fabricate the peices. I put the hobbycnc kit on it and have used it with a dremel and a 1/4 router as well as a rotozip. I think the rotozip works best for my application. If I can find plans for some A320 throttle parts they will be my first cuts for the sim.

For software I ahve only used Mach3, and am still getting to know it. Cost was about $550 total. Only thing I would do differently is use stainless steel guide rods instead of just cold-rolled rods.


Saw a CNC kit in recent nuts and volts too, looked pretty awesome.

Buddy

AndyT
01-11-2009, 05:42 PM
That $550 includes table, motor and software? That sounds like a very good price.

Buddym
01-11-2009, 09:16 PM
nah, the $550 was everything except software, but I use free and trialware and some others. The plans were easy to follow, I was surprised at how well it worked.

Buddym
01-26-2009, 05:36 PM
I mentioned earlier in this thread that I had built a cnc machine. here are some pics of a few A320 throttle lever parts I just cut. I can't believe I marked the bottom dimension wrong on the paper! Wonder what they are supposed to be anyway....

Kerbo
01-26-2009, 11:36 PM
Those look great. What material is that, hardboard? What kind of bit did you use? I've been thinking of pulling the trigger on a DIY CNC. So many projects, so little time. :grin:

Thanks for sharing.

Buddym
01-26-2009, 11:58 PM
Thanks! These are cut from cheap mdf hardboard from Lowes. I am planning on cutting some from the grey cpvc/pvc to see how they come out, but these are very sturdy, so I may just put them together , sand/prime/paint and see how they come out. Actually, I am not at all sure about the dimensions of these parts, so I may end up laminating the parts to each other in pairs to get it closer, it's so hard to tell just from the photos I see here.

The bit is a 1/16" stainless/carbide end and side mill on a 1/4" shank. The cuts were made .04" per pass so it took a while. My machine uses threaded rod for drive screws so it is pretty slow, about 10 inches per minute on a straight cut. That's ok with me, I have more time than money, and it's cool to watch it cut, at least the first few dozen times! Sorry if my terminolgy isn't the correct machinists lingo, I am pretty new to CNC and machining in general.

The CAD part of this is the hardest part for me, I am not much of an artist. I am pretty good at electronics, programming, and building things in general (although not in the same league as some of the builders I see here).

If you have a few parts you want to see cut in this stuff send me a clean dxf file and I will knock em out so you can have a look at them (nothing too big, please).


Buddy