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tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,365

CNC Machine - Computer Numerical Control

This topic is offered for NewMars members who might wish to help to build a collection of knowledge/insights/tips about CNC machines.

It turns out that our Phoenix contact (see Phoenix water topic) has some experience with a specific brand of CNC machine, and has done quite a bit of reading about the field in general.

While this topic will not be advertising any particular brand, we do have the opportunity to compare brands of machines.

In addition, we have the opportunity to compare software that generates the ".NC" files that are fed into the microcontrollers of the machines.

From what I am learning, the CNC machines that a home workshop might set up are fitted with a router, so the brands of routers may be appropriate for discussion.

I get the impression the router on the machine in use by our Phoenix contact may have been designed for that machine, so it may have features that would not be available on a generic router.

While the anecdotes and information to be collected here are going to (necessarily) be from and about Earth, it seems to me that CNC machines will be a part of the landscape on Mars.

(th)

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,365

Re: CNC Machine - Computer Numerical Control

This post is reserved for an index to posts that may be contributed by NewMars members over time.

(th)

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,365

Re: CNC Machine - Computer Numerical Control

This post is reserved for information provided by our Phoenix contact by email.

Permission will be required, and the emails may need to be edited for display here.

Permission to edit the email correspondence for display here was granted, so I'll add that to my to-do list.

I've divided multiple emails into two posts. The first is a summary/overview and the second will be additional information/insights/suggestions

On Friday, November 1, 2024 
<snip>
This is a small primer on CNC machines. As with a 3D printer, you first must design what you wish to accomplish or get free designs from places like "Thingiverse" or its alternative competition as there are dozens. When you first begin the design process, you need a CAD equivalent to work with like AutoCAD, Illustrator, Corel Draw, Fusion 360, or even Blender. Inkscape is free for Windows and Mac, and perhaps Linux. After the design comes the CAM process in which the design or CAD process interacts. This application process allows the router to define its movement based on workspace available, type of router bit used, depth of cut, spindle speed, and a host of other factors used in a coordinate system. Most CNC machines use Arduino that works with a controller to define movement. That movement is defined by GRBL and G-Code. "G-Code is a set of commands for the CNC machine to follow and GRBL is an open-source software that translates the G-Code commands into motion control instructions for the CNC machine."  I use a program called UGS to work as a simulator that tells me the direction of travel and the time it takes to begin and finish the design. There is a free online program called Easel (by Inventables) that can design whatever you wish, and also create and export the G-Code commands  into a .nc file which CNC machines understand. You can use a program like UGS to open the file, and complete the process. <snip>

Yes, it is programmable in the sense that you follow the previous paragraph. The router I used and purchased with the machine was inclusive and the spindle goes to a maximum of 10,000 RPM (revolutions per minute). For me this is all I need as I make mostly 2D lettering and small triangles, rectangles, and squares on pinewood or birch. I use acrylic for making templates. Most hobbyist professionals use up to 20,000 RPM using either Dewalt or Makita routers for less than $200.00.

You hold the wood or material down by using clamps which are normally provided by the machine manufacturer and/ or applying blue painters tape to the top of the machine and painters tape to the back side of the material and then get a super glue spray to apply to both open sides of the painters tape. Then place them together after gluing. You then peel off with a scrapper after finishing the project.

Your Woodcraft person is not correct as you must decide the feeds and speeds rate, and after that, it is trial and error. With Easel, it is a suggested rate, but 90% of the time you would need to make manual adjustments depending upon the wood and bit used, or does this project take two stages for roughing and then detail. This means you would need to change bits for each stage. That's where ChatGPT comes in strong for me. Believe me, I have broken many bits in this process as well.

The acrylic supplier usually sell them in sheets, or if they have remnants left over, they will sell those. Remember, it must fit in the workspace area so the acrylic supplier will have to make cuts to fit the work area. They charge typically a fee for cutting to fit unless you have a table saw with an acrylic blade and do it yourself. I use 1/4" acrylic and cut my templates with a CNC machine or a laser cutter which is so much faster.

Last thing about CNC machines! Should you purchase, make sure you have plenty of support. That is what is lacking with Chinese machines. The two previously mentioned is popular in the US and Easel is now offering a comparable machine. Their support is awesome.
<endSnip>

(th)

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,365

Re: CNC Machine - Computer Numerical Control

More correspondence from our contact in Phoenix:

On Thursday, October 31, 2024
<snip>
For me, working on a single project for hours or days can be fun for some, but I like a CNC machine for its quickness with acrylic and wood, which is mainly what I use it for even though there are metals and other material to carve. I use a Genmitsu ProverXL 4030 V2 machine. Here is a link to the machine: ProverXL 4030 v2 . On Amazon, it will probably be on sale for $999 as I saw it on that price earlier this month. For me, the big problem with this company is support. Everything is done by email about 5 days/week from China with weak options sometimes. For the first year, I needed parts, but all of this lasted about 6 months before everything started running smoothly again. The parts were all free with quick 3 day shipments but it turned out to be trial and error, and I ended up with a lot of good extra parts like stepper motors which are in excellent condition. I would now purchase a FoxAlien machine or Shapeoko which I understand has excellent support from USA. The way that I learned all of this is from YouTube videos and ChatGPT. When I had questions, ChatGPT always had good answers. For you, you may wish to use Fusion 360 which is free to hobbyists. You should be able to import, design, and print 3D objects directly from the software. I use an Illustrator type of software called Corel Draw for design and Easel software for Arduino tasks. 
<endSnip>
Sent: Saturday, November 2, 2024
<snip>
Thanks for this great advice!  And thanks for doing the research to discover that the brand Woodcraft carries is Shark!  The comparison with Home Depot is interesting. The quality of sales staff varies from store to store. I find that the knowledge/experience varies greatly from store to store, and within a store, over time, as folks come and go.
<endSnip>

On Friday, November 1, 2024
<snip>
Most good CNC machines have an adjustable spindle speed on the controller. Woodcraft is a large national company and sells its products and CNC machines at a premium. Rule number 1 - Check to see if they offer support for their machines. I think you have to work directly with Shark which is not a well-known brand and is sold exclusively for Woodcraft and Rockler. There are 3 or 4 Woodcraft companies in the Phoenix area. The 3 CNC companies that I mentioned offer great support. Easel offers support as well on Sundays. To me, buying a CNC machine from Woodcraft is like buying one at Home Depot. The software that is used is the Vectric Vcarve which is a popular software that runs about $350, so I would also be concerned about the actual workspace you will actually have as well as the replacement parts. The saleslady is correct as this software allows you to design your own project and create a toolpath which Easel does for free. For most CNC machines, the bed size and the workspace size are totally different.
<endSnip>

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