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Forum topic by BorrielloOBWS posted 01-22-2020 11:42 PM 486 views 0 times favorited 22 replies Add to Favorites Watch
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BorrielloOBWS

5 posts in 31 days


01-22-2020 11:42 PM

Topic tags/keywords: cnc legacy shopsabre camaster high school woodshop help spindle vetric aspire question resource

Hi,

I am a high school shop teacher in Central New Jersey. We are looking to purchase a CNC for our shop/classroom. Our budget is 20K and must include everything we need to get started. I’ve done a bunch of research, but the more research I do, the less confident I get with the decision.

There are 2 things that are very important 1) Quality of the machine. The machine must be built to last and be able to stand up to the wear and tear of daily student abuse. 2) Customer support. I’ve never used a CNC machine before, and I’m going to need all the help I can get.

I’ve narrowed it down to 3 different Machines all would come with Vetric Aspire.

1) Legacy Maverick 36” x 60” $19, 561 water cooled 3HP Spindle Comes with t Track and Clamp set and a Router Bit Set

2) Shopsabre 23 30”x 40” $18,234 air cooled 2.2 HP spindle, Laser Engraver, Vacuum hold down system, bit set, Phenolic table top upgrade

3) Camaster Stinger SR-24 25” x 48” $15,765 air cooled 2.27 HP spindle, Laser Engraver, Fast Tool Change kit w/ Laser cross hair, vacuum hold down system

When I put the Legacy up against the other 2 it looks like a much better machine, bigger cutting area, water cooled spindle vs. air cooled, etc. However, I am concerned about their post purchase assistance. If anyone has any input, opinions, or resources, it would be greatly appreciated.


22 replies so far

View Madmark2's profile

Madmark2

839 posts in 1225 days


#1 posted 01-23-2020 01:18 AM

Hardware aside your students need to learn g-code programming.

Mach-3 is the usual control software. Require a clean sim run before actual cutting.

AutoCAD .DXF files can be easily converted to g-code so you can go from screen to metal.

Invest in limit switches to reduce crashes.

Metal cutting needs a lube/coolant spray. Base deck needs to be waterproof, have drainage and needs a hold down system. Most control software does NOT know to avoid crashing into hold downs.

Have fun!

-- The hump with the stump and the pump!

View BorrielloOBWS's profile

BorrielloOBWS

5 posts in 31 days


#2 posted 01-23-2020 01:20 PM

We will be working with mostly wood and maybe some plastics, I probably should have included that in my initial post.

If I can be honest, I have no idea what you’re talking about. I went to a seminar at Woodcraft and learned the basics. He created something in Vetric V Carve Pro and uploaded it to his CNC. He used some terms i was unfamiliar with like vectors, but never mentioned G Code.

Also dont know what a limit switch is….

One of my fears is investing an enormous amount of money into a piece of equipment and not being able to use it. I’m trying to educate myself, but its a slow process. Looks like I have some more research to do.

View Madmark2's profile

Madmark2

839 posts in 1225 days


#3 posted 01-23-2020 02:06 PM

Limit switches are just that, they limit the gantry travel electronically before it crashes mechanically.

Vectors are how the cutter moves – from one point to another directly rather than moving over and then up.

CNC software varies by machine and has more or less integration with drawing software. Without software the CNC just sits sucking power.

G-code is an old software standard CNC machines have used since punched paper tape was hitech. This is the base level software for essentially all CNC.

Mach3 is free cnc control package that gives you an operator’s console with manual controls, position displays, and the ability to create, save, simulate, test and run gcode programs. It can also load, debug and run gcode programs from any source including hand entered.

Since gcode is persnickety, vendors have written various packages to make life easier, but these vary from vendor to vendor and there is little standardization.

AutoCAD is the industry standard drafting program. It produces editable geometry files called .DXF (Drawing eXchange Format) files. These files can be translated by software you or your students write once directly into gcode which is in turn executed by the mach3 program to actually move the cutterhead.

Gcode has commands to move in x, y, and z simultaneously, turn the cutter motor off and on, cooling pump off/on (not needed for wood), etc. but you also have to have the hardware to make the commands work. This will help you decide on the hardware options you need to buy / wire. Talk to your vendors about accessory control.

M

-- The hump with the stump and the pump!

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BorrielloOBWS

5 posts in 31 days


#4 posted 01-23-2020 02:18 PM

Thank you for your help! Goal is to get a little smarter everyday and hopefully be able to prepare my students for some 21st century careers.

View DS's profile

DS

3377 posts in 3057 days


#5 posted 01-23-2020 02:37 PM

G-code is the fundamental script that determines the movement of the machine tools.

https://en.wikipedia.org/wiki/G-code

No matter which software you use to create the model to be cut, it has to be reduced to g-code to run on the machine. In a nutshell, it is a simplistic x, y, z coordinate system that describes tool movement.

G-code is the result of tool paths created in the CADCAM software after being processed by a post-processor that is unique to the specific machine that is being used.

All CNC machines use basic g-codes, but many have special codes and unique configurations that the post translates to the tool paths generated by the CADCAM software.

Vectric V-carve Pro created a tool path based on the model that was designed, but on the back end, it created g-code from those tool paths for the machine to follow.

This is going to be a long process. Even if you manage to find a turn-key solution for your price, it will have a huge learning curve. Be patient. Make sure you understand all aspects of the process before you commit big $$ to this endeavor.

-- "Hard work is not defined by the difficulty of the task as much as a person's desire to perform it.", DS251

View Joe Andrews's profile

Joe Andrews

78 posts in 2636 days


#6 posted 01-23-2020 02:40 PM

Couple of things:

Mach3 is NOT free. It does have a demo mode that will let you run very small programs limited to 500 lines of G-code. It has been the standard for a long time, but there are other options out there, such as UCCNC or LinuxCNC.

G-code is a set of commands that Mach3 uses to tell the machine what to do. For instance, if you wanted the gantry to move to a spot 5” X and 5” Y, you would use the G0 code like this:

G0X5y5

There are codes to turn the spindle on and off, set spindle speed, set feed rate, etc. In the old days, programmers used to write the G-code by hand, but today’s CAM programs, such as Vectric Aspire and VCarve generate all the code for you. I agree that it is good to understand what the code does, but in the 5 years I’ve had my machine, I’ve only had to modify what Vectric produced a couple of times. I sometimes type codes manually to move the gantry to s specific spot, but that’s about it.

One other option to consider: Since you’re in a school environment, it might be good to build one from a kit. That way, you understand what each part does and how it all goes together. Avid CNC makes some really nice machines that will fit well within your budget and provide great service.

As far as size goes, if you have room, go as big as you can. Having the capability of putting a full sheet of plywood on the machine is a real plus if you ever plan on doing any cabinet work. That said, my machine has a cutting area of about 52”x45” and I’ve never used more than 48”x36”.

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Madmark2

839 posts in 1225 days


#7 posted 01-23-2020 02:41 PM

You can get an entry level system (in kit form) for $2500 or so if you shop around. These use standard routers like the PC 693 instead of massive water cooled spindle systems (spindle cooling is usually only for metal cutting). Start with that and grow into the $20k machine. The same gcode should run on both. Let your students build the hardware and develop the software, it’s not hard.

M

-- The hump with the stump and the pump!

View BorrielloOBWS's profile

BorrielloOBWS

5 posts in 31 days


#8 posted 01-23-2020 03:18 PM

Appreciate all the feed back.

Problem is, in the field of public education, its very difficult to get things like this done. We never know whats coming around the corner. The money is there now and its been allocated, so if I don’t go for it, the opportunity may not present itself again. I have to buy this thing once, if i present the idea again in the future they will say you have one and we don’t have the money right now for an upgrade.

I’m confident that, over time, that we will be able to produce some cool projects that will teach the students how to operate and understand a CNC. Just need to do my homework. I also need to figure out the best machine for us inside our budget.

View sras's profile

sras

5310 posts in 3766 days


#9 posted 01-23-2020 03:51 PM

If your budget is $20K and that needs to cover everything I suspect you’ll run out of money before you get a $18K+ machine running. I am not a CNC user (much less an expert), but there could be additional expenses beyond buying the CNC itself. I’ll toss out some possibilities and let more informed people critique it. Some “extra” items might be:

Control software (g-code) – there are free options but they may not meet your needs
CAD software – the g-code is a list of instructions for the CNC. You’ll need a design to convert to g-code. Again there are free options and you may already be set up for this.
PC(s) – the CNC package may include this but you might need to buy one. If you are just getting started on CAD then you’ll need to fund that
Cutting bits – they break/wear out and are not free
Dust control – depends on current capability
Electrical – do you have the amps/volts needed in your shop or will electrical work be needed? Are there extra safety requirements for public education compared to industrial set ups?

Hopefully others with more knowledge can clear this up. Is there anyone in your school district that could serve as a consultant to help you out? It could be a local business that might be able to consult in exchange for some positive publicity…

-- Steve - Impatience is Expensive

View Mario's profile

Mario

191 posts in 4033 days


#10 posted 01-23-2020 04:16 PM

Shopbot, by all means if quality and customer service are your priorities, they also have special programs and price tags for schools.

View Lazyman's profile

Lazyman

4660 posts in 2024 days


#11 posted 01-23-2020 05:15 PM

I just started coming up the learning curve and as a beginner yourself, I think that you need to walk before you run. I would not dive in with a single $18k machine to start with. I think that is a recipe for frustration both you and your students. You need a learning platform not a production machine, at least for an entry level type class. . With a single high end machine, you will only be able to run a single job at a time and each job could take anywhere from a few minutes to hours to run, depending upon the complexity and size, so it could take weeks for each student to execute a single large scale assignment, unless you intend to run the jobs yourself in your spare time.

My suggestion is to get several smaller and cheaper machines that will allow the students to explore and learn the capabilities. Hobbyist machines will run on standard 120v service and may be small enough that you can move them out of the way while you are doing other stuff. You may even be able to get some of hobbyist CNC companies to give a deal on the machines, software and support. While the quality is lower, one of the nice things about using cheaper hobbyist machines is that if they do get damaged, they can be repaired or replaced more cheaply than a production quality machine. If somethings happens to your high end machine, will you be able to afford fixing it? Going with cheaper machines will also save some of your budget for tooling which is one of the consumables you have to include in your budget especially going forward. They wear out and you will break bits along the way. Dust collection may also be cheaper with lower end machines because you can usually just use a standard shop vac. Noise abatement can be issue with any setup so you may need to build or buy enclosures. Water cooled spindles are supposed to be much quieter but I am not sure what that means for your workspace.

You will also need multiple computers with software to draw, design and in some cases control the machine itself. Having a single computer could create another bottleneck, unless you find a cheap software solutions that allows each student to work on their own computers or at least on many computers. Unless the intention is to take someone else’s design and simply demonstrate what a CNC can do, the design process is at least half the end-to-end process.
The software stack includes
  • CAD software to create the design drawings
  • CAM software to convert the pretty picture into gcode
  • Some machines also come with control software that sends gcode to the machine and manages the milling operations
  • For beginners, a simulation package might be a nice optional package to help them test their designs virtually before actually running it on the machine and destroying your media. In fact, creating and then simulating the execution can be the first part of the learning process and at a minimum could even be a requirement before you allow them to run it on the actual machine.

Note that many of the hobbyist machines come with software that is sufficient for basic design and execution. Several come with a version of Vetric Vcarve which will do basic CAD design and create the gcode for your specific machine.

As for the gcode thing, while a basic understanding of the gcode is a good idea, I would not worry about that too much for an entry level CNC class. The right software stack will handle 99.9 % of what you need and manipulating the gcode is a more advanced topic for more experienced users. At the early stages, it is generally a good idea to let the software do all of the gcode. This IS a great way to help students understand why math is important when they do not see a practical use for themselves. Maybe you can get the math department to chip in some bucks!

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

View Brawler's profile

Brawler

121 posts in 467 days


#12 posted 01-23-2020 05:53 PM

You are in a school, call the sales reps. They can educate you on what you will need. If possible have all three come to see you. Tell them you are going to get three quotes and then you will make the decision. These guys know their machines and have probably helped others in similar situations.

-- Daniel, Pontiac, MI

View BorrielloOBWS's profile

BorrielloOBWS

5 posts in 31 days


#13 posted 01-23-2020 06:27 PM

I called the three stated companies and received three quotes (prices also in original post). Some even gave educational discounts. But these guys are in the business of selling…they are going to say why their machines are the best and their competitors is not. Looking for someone who has had experiences with Legacy, Shopsabre, or Camaster. Or some suggestions to go with another company or route. I am really thinking about the suggestion to go small and learn before taking the leap into an industrial CNC.

View Madmark2's profile

Madmark2

839 posts in 1225 days


#14 posted 01-23-2020 06:47 PM

From a programming and layout standpoint a little machine behaves just like a big one. For teaching technique, you could get a shop full of smaller machines and one big one for final full size work. More students can learn at once. Less down time.

-- The hump with the stump and the pump!

View Lazyman's profile

Lazyman

4660 posts in 2024 days


#15 posted 01-25-2020 01:53 PM



...I am really thinking about the suggestion to go small and learn before taking the leap into an industrial CNC.

- BorrielloOBWS

I really believe that this is the best approach, especially since you are currently the student as well. It will give you a platform to learn enough to start teaching and also give you an idea what you might want with higher end machines. Something like the X-Carve is a relatively turn-key solution that won’t break the bank. Inventables.com gave a bunch of X-Carve machines to various YouTubers a couple of years ago so there are tons of videos that show what it takes to get them up and running and various things you can do with them. At one time I think that they had programs that allow their Easel Pro software to be used by many students so this may save you some costs as you begin as well. I would call them and see what they will do to help out a school trying to start up a program. If you tell them you are evaluating various machines that will fit into a curriculum, they might even give you a machine for evaluation?

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

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