Large Scale Central

Getting started with CNC routing

Modeling Technical Modeling
#1

While 3d Printing has a certain attraction, I think I might get more use from 3d routing, then branch off into 3d printing, most likely farming those tasks out to the likes of Jawstec for the final product.

Where to begin? I reached out to Cliff Jennings, and he suggested I start a thread.

Eventually, I’ll have to decide on a machine, and there are a number of well reviewed machines for less than $300 US

I know I will need some software: something easy to learn and use. I have some experience with the likes of Visio.

From a 50k ft. view: I know that…

I need to specify to some software where to start a router bit in X,Y, and Z coordinates and do this for each movement of the bit.

I need to load this instruction file into a controller that in turn tells axial stepper motors where to place the ‘head’ of the CNC machine in these XYZ dimensions.

The question(s) are about how/what to piece together to come up with a solution that will help me create the parts I need, and do I need to learn/study to get there?

Thanks in advance,

-Wes

#2

I have an older Probotix Fireball V90 CNC machine. It was a kit but I don’t think it’s available anymore. One of my all time favorite tools!

I mostly use it to cut out sheet styrene to make buildings for my layout.

The kit came with everything, I just had to supply a PC and install LinuxCNC on it (real time Ubuntu, its free) The PC connects to the stepper motor control box, cables then go to the three stepper motors.

Basically you load a Gcode file into the LinuxCNC app and it does all the work of moving the motors while cutting.

To make the gcode file, I use two apps, both free software.

I use InkScape to prepare a flat drawing of the walls and window openings. I export that as a dxf file.

I then import the dxf into the free version of CamBam. You can select each of the lines or entire sets of lines (layers) in Cambam and create an ‘engrave’ path at a certain depth (z) setting. You also set the bit travel speed for the path.

Once you set the paths to the depths you want, you export the gcode file. I then use a thumb drive to carry the file out to my shop where the machine is.

That is a very simplistic explain there, I can post up more detail if you like.

Here is my latest creation:

Mobile Home

Few more pics of buildings and the router are here:

http://martinsant.net/?cat=43

Martin

#3

Great idea for a thread. I have a 3d printer, and would LOVE a laser cutter, but I think a CNC router is more in my budget.

#4

I recently picked up the Sainsmart Genmitsu CNC 3018-Pro for $200 and am extremely impressed with the build quality and first test. I’m learning CAM via Youtube and trying to convert my cad files to grbl for milling.

#5

That is impressive. Can you elaborate on bits, speeds and software and such that you used to make that? Also any of those Youtube links you have found useful. I have mostly been cutting out flat parts and leaving the detail to 3d printing. I need to expand my horizons :slight_smile:

#6

Martin Sant said:

That is impressive. Can you elaborate on bits, speeds and software and such that you used to make that? Also any of those Youtube links you have found useful. I have mostly been cutting out flat parts and leaving the detail to 3d printing. I need to expand my horizons :slight_smile:

I cannot take any credit for the awesomeness of the test print. The gcode for that dragon carving is included on the USB stick with the printer. I haven’t a clue as to how to do that myself as I pretty much just hit go! I’m converting SVG files with some success and watching videos about using Easel and Candle. So far, I cannot recommend any videos as I’m not even sure if I’m using the best software. I’ll post more here once I get a better handle on this. My first idea was to do container sides and roofs out of PVC and I’d really like to make these Hopper toppers to convert my Aristo coal hoppers for grain hauling.

#7

I’m very interested in this thread. We have an older Gerber commercial 4’ x 8’ bed CNC router at work. The lead operator wants to retire and has taught most of the how-to to our designer, but they need a back-up operator and that could be me. The software currently in use to draw parts is ancient and horrible. I’m pretty sure the router drive software could be adapted to render design files from more modern / capable software.

We use it mostly to cut composite aluminum and foamed PVC board to create background shapes, individual letters and to carve signs from High Density Urethane foam and PVC board. I’ve inquired of the operator as to how fine detail he thinks it can do and got the answer: no clue; let’s try it. My only issue is the .25" shank bits for are expensive and they have no need to buy any of the small tip sizes. I’d like to carve brick from HDU foam.

#8

I have been pushing for years to have someone come up with a rivet embosser using a CNC mill. With 2,000+ rivets on the EBT M-1, we need something to produce unique rivet patterns on strips of brass or styrene.

#9

Pete Thornton said:

I have been pushing for years to have someone come up with a rivet embosser using a CNC mill. With 2,000+ rivets on the EBT M-1, we need something to produce unique rivet patterns on strips of brass or styrene.

I don’t think that would be too difficult. Any CNC type device should be able to handle by replacing the business end with a punch. The Cricut Maker would probably be easiest as it’s actually designed to emboss. Could probably make the panels for Amtrak cars and the like as well.

-Dan

#10

So why don’t we have a folder of gcode files as a cooperative? Sub-folders by subject: building details, rolling stock, locomotive parts etc?

#11

Wesley Stewart said:

So why don’t we have a folder of gcode files as a cooperative? Sub-folders by subject: building details, rolling stock, locomotive parts etc?

Very impressive idea. But, there IS human nature to consider.

  1. Most of this stuff is VERY hard for us older guys™ to even comprehend.
  2. Many people feel that since it took THEM a long time to learn something, it should TAKE everybody even longer to comprehend.
  3. Many folks just HATE sharing. I thought I was really naive about this, but it turns out that many folks want SOMETHING/ANYTHING to recompense them for the personal suffering that they encountered. Yep, even if they didn’t suffer.
  4. Sure, I’ll share, but I better get SOMETHING out of this SELFLESS gesture!
  5. There’s already a place where THIS is done, it’s called THINGIVERSE.COM.
  6. Probably something that I had NEVER even considered. YMMV.
#12

BTW, Martin, VERY NICE work on that “Mobile Home”, even thought it was NOT referenced in you link (Oooh. Some OTHER GREAT work.).

Well done!

#13

Thanks Bruce. I broke a lot of bits and melted lots of styrene before I started getting decent results. But it’s fun. Model Trains has all these hobbies-within-hobbies.

If anyone is interested, I don’t mind sharing - here is a zip of all of the files I used to make the mobile home. Everything is in there, the svgs, dxf and gcode files I made in inkscape/cambam and the 3d parts I printed on my ender3. It’s the first time I used a ball nosed bit on some of the cuts. The grooves in the siding are from that.

http://martinsant.net/mobilehome.zip

I also use a free 3d modeling program to make some of the shapes. You can get that here:

https://www.daz3d.com/hexagon-3d-modeling-free

#14

I can certainly relate to the older guy comment.

In terms of ‘what’s in it for me?’ I would think the exchange of files would be motive. At some point there are takers instead of givers; granted.

I’d give my (making this up) SPNG cab details in exchange for a flat car…etc.

Just a thought.

#15

I collected a few items from thingaverse, but when it comes to Ender Pro printers

https://www.amazon.com/s?k=ender+3+v2&crid=P0B639DLNS3K&sprefix=ender%2Caps%2C233&ref=nb_sb_ss_ts-o-p_5_5 there are a bazillion choices. How do you decide?

But that’s printing… what about routing?

-WES

#16

Wesley Stewart said:

I collected a few items from thingaverse, but when it comes to Ender Pro printers

https://www.amazon.com/s?k=ender+3+v2&crid=P0B639DLNS3K&sprefix=ender%2Caps%2C233&ref=nb_sb_ss_ts-o-p_5_5 there are a bazillion choices. How do you decide?

Many of those are actually the same - Just different vendors. I went with this one https://www.amazon.com/gp/product/B07GYRQVYV It works well for most things as is but you will more than likely find a need to modify and/or upgrade components. I upgraded the hotend and bowden tube to print ASA. 3d printers do require a bit of tinkering from time to time.

#17

I just saw your thread Wes, thanks for starting it!

I’m enjoying what the CNC router users have to say, 'cause I only have the laser cutter.

From my limited knowledge, I’d like to take a whack at a list of the benefits of the two approaches, just because y’all have got me thinking.

CNC router:

  • Can do 2D cutting (if you program for the kerf of the tool)
  • Has DEPTH to its cutting (the Z dimension), not just 2D cutting
  • Can cut materials the laser can’t (because of toxic offgassing while lasering)
  • No flames involved

Laser:

  • Has a cutting / kerf width so thin that it can be usually ignored; interlocking pieces can be separated by a single lasered line
  • Can make very sharp inside corner cuts (minimal radius)
  • Very quiet (most noise for me is from the exhaust fan)
  • No sawdust involved, or dust collection system (though a good exhaust vacuum-blower is mandatory)
  • Can engrave complex images (e.g., grayscale versions of photos)

I’m sure you guys can think of other benefits for one approach or the other, so please post them.

#18

Thanks, Dan. So does it come with filament? What size/spec filament is required?

#19

Filament is relatively inexpensive, just make sure you dont go too cheap. And keep it bagged when youre not using your printer, because it can soak up humidity and cause problems. I’m a big fan of Hatchbox filament, but I’ve also used Overture as well. Every filament takes a bit of dialing into get the temperatures correct, but you get used to fiddling with the printer.

#20

Cliff - one thing I would add to the CNC side is that you can get a drag knife for it to cut vinyl and decals. I just got one for $20 off of Amazon but I have not tried it out yet as I’m not quite sure how to mount it.