CNC Router vs 3D Printer

[Akash Rastogi]

What kind of projects do you expect to be working on while you finish up school? Do you usually design more 3D parts than you do 2D (or tubing)?

Hard to weigh in without totally understanding what you want to create for your projects, but for prototypes of mechanical systems, I would think a router would be a good way to go. As we've seen before, you can cut out your own plate sprockets and such, and cutting chips on the router would still be faster than waiting for something to print (usually). Also, don't forget about being able to prototype in plastics and wood! I think the decision also depends on what machine at your school's machine shop is usually more readily available.

Personally, I love FDM printers and have used printed parts on many occasions, and the kids on 11 got to use a few critical printed parts on this year's robot as well. I think our parts were all printed on a Dimension 1200, but I don't recall exactly. The ABS, when printed correctly with the correct parameters, was really great for my applications as well as 11's (gears, spacers, couplers, collars, dog-bone linkage on 11, sensor mounts, etc). Nothing was in high load, just parts that we didn't have time to have sent out for conventional machining, or it was a bit too complex to machine easily.

Just a thought - if you do end up with a CNC router, I would think that modifying a bed and adding a 3D printing head would be a decently easy project for when you have some free time. You could, in the long run, make a hybrid machine with swappable heads, no? Or is that a silly idea? Probably a silly idea

[techhelpbb]

Originally Posted by Akash Rastogi

Just a thought - if you do end up with a CNC router, I would think that modifying a bed and adding a 3D printing head would be a decently easy project for when you have some free time. You could, in the long run, make a hybrid machine with swappable heads, no? Or is that a silly idea? Probably a silly idea

No it is quite doable. Just remember though to add a heated bed to the printer.
Both machines use G-code and M-code. All you need is a head and to list it as the spindle with perhaps a temperature controller which you can get or easily make yourself.

Heated beds are really as easy as a resistor, nichrome wire, or Inconel welding wire. Just put it under the work area with a proper temperature control that you could also use to control the head. An Arduino and temperature sensors like: thermistors, 2N2222 transistors or Dallas Semiconductor temperature sensors is all you need to make a multi-channel temperature controller (you can also buy them off E-Bay). Just make it so you set the temperature from another interface and turn the heaters on and off from the CNC control (this is actually really easy to do). If the entire machine is already enclosed to control swarf the heated bed will work just fine. All the work bed needs to be is a piece of aluminum covered by Kapton sheet or a sheet of glass.

You will want a heated bed for anything larger than 2" on the bed. It will reduce the warping that will start as layers build.

[DonRotolo]

Your point about the mess and noise of a CNC router - in a college dorm environment - cannot be ignored, and it is not trivial. Plus, CNC routers tend to be heavy, several hundred pounds perhaps.

So simply from a "where can I put/use this thing" point of view, a 3D printer is your better option.

Some different opinions on several 3D printers in your price range: http://kronosrobotics.com/3d/index.shtml

[AdamHeard]

Originally Posted by DonRotolo

Your point about the mess and noise of a CNC router - in a college dorm environment - cannot be ignored, and it is not trivial. Plus, CNC routers tend to be heavy, several hundred pounds perhaps.

So simply from a "where can I put/use this thing" point of view, a 3D printer is your better option.

Some different opinions on several 3D printers in your price range: http://kronosrobotics.com/3d/index.shtml

I missed the information about the dorm room.... That's a gamechanger. A router of any real work ability is not happening in a dorm room.

[Mk.32]

Oh... yeah a Router is NOT happening in a dorm room. They may not even let you bring in an 3D printer based on the heating element (Mine doesn't let you bring appliances and lava lamps).

For a college your best bet would probably be gaining access to an shop on campus via a club or getting to know the instructor. Or finding an local makerspace or hackerspace.

[techhelpbb]

Originally Posted by Mk.32

Oh... yeah a Router is NOT happening in a dorm room. They may not even let you bring in an 3D printer based on the heating element (Mine doesn't let you bring appliances and lava lamps).

For a college your best bet would probably be gaining access to an shop on campus via a club or getting to know the instructor. Or finding an local makerspace or hackerspace.

Where there's a will. There's an incandescant light bulb bed heater.
It's becomes more an Easy Bake Oven anyway.
What I didn't bring the heater with the printer...I just found it here

[kaliken]

I saw a couple people say it but I don't think the community really did latch onto it.

First off, You are in college. You are paying to go to school there. Use the machines and the facilities you are paying for! There is a reason why they have a machine shop. Its not only for research but its also the place you can learn proper machining practices. I cant tell you how much I learned from my shop managers.

Second, learn to manage your time to maximize machine shop usage. Know that the machine shop has open hours, or that sometimes you may not have access due to senior projects. But.... if you get in good with the shop guys then there are untold benefits. (ie running CNC's later at night, or even a paid stipend..)

Third, if you are in a dorm room... it just seems silly to try to pack something like that in. Enough said.. Off campus living then maybe, but then again I would refer to point 1.

When you graduate and get a more permanent place.. then by all means go for it.

But then again that is my 2 cents.

[protoserge]

If the school shop doesn't work out, there might be a maker space within range. I would venture to say your funds would go a lot farther (a lot more tools for the dollar), even if you have to pay a few bills for a monthly membership.

[Arch3Dpt]

Could an arch-welder head be used as on a 3D printer?

[protoserge]

Originally Posted by Arch3Dpt

Could an arch-welder head be used as on a 3D printer?

You can use a similar CNC technology and a proper table (think plasma table) to do 2D robotic arc welding. Many industrial welders use robots.

You are probably closest in thought to laser sintering, which uses lasers to form layers in metal powder as in a 3D printer.

[EricH]

Originally Posted by Arch3Dpt

Could an arch-welder head be used as on a 3D printer?

Could it? Probably.

Is it going to be useful? Possibly--most 3D printers that could be modified for an arc welder tip are under a foot of travel in any direction, which may or may not affect usability (though it'll certainly affect size of parts that can be welded). Also I can't think of anything that would need that much precision (we're talking in thou here) in terms of arc welding. Might want to try a CNC router modification first.

Is it a good idea? No. There's a lot of stuff that could go wrong, ranging from melting plastic (reprap-type machines) to warping the print surface (VERY bad if you ever want to change back) to any other safety concerns with exposed welding.

As stinglikeabee pointed out, you're pretty close to sintering, but those types of 3D printers are a minimum of 6 figures, not counting material cost--and in some cases, shielding.

[Andrew Schreiber]

Originally Posted by techhelpbb

No it is quite doable. Just remember though to add a heated bed to the printer.

Assuming you are printing ABS.

OP, I own a Replicator 2X and it has truthfully been a colossal pain in my rear... of course, we own the same one at work and it seems to be configured properly. I think I need to tinker with it more.

For FRC parts, I would agree that the raw printed plastic is simply not strong enough for anything more than sensor mounts. However, if you are not averse to casting some components it should work well for making masters for silicone molds and pouring urethane casts.

Personally, I went with the 3d printer due to the fact that I don't have a garage of any sort at this point in time. If I did I'd probably have gone with a small CNC mill or a mid sized router capable to handling aluminum. In fact, if I ever do get a place with a garage I will most likely be purchasing the router.

[EricH]

Originally Posted by Andrew Schreiber

Assuming you are printing ABS.

Heated beds also help with PLA. Speaking from experience here, though, a lower temperature helps more with PLA.

[CENTURION]

As others have said, a CNC router is going to be a lot more versatile than a 3D printer. However, in a college dorm room, a router is going to be right out. It's going to be loud, heavy, and very messy.

If, for whatever reason you were still interested in a router though, you can build a very nice one on your own for your price range. If you've built FRC robots, you already have 90% of the knowledge required to design and build a CNC router. This fella on youtube is what I always recommend people check out. He built a home CNC router out of 80/20, with great accuracy, and more than enough rigidity to cut aluminum without issue, for I think $2500 or so. He's also mentioned that he's working on a kit version that he will sell if he gets enough interest.

He's got tons of video documentation, as well as a number of videos explaining components that the average person might not be familiar with (Linear guides, ballscrews, etc)

[magnets]

Our team has a 4' x 8' CNC router, and it is the tool our team uses the most. It's awesome for prototyping, as we can make shooter rails out of plywood or hdpe in less than 10 minutes. If you plan to cut aluminum sheet on it, try to ask the manufacturer/distributor which settings will work the best. You need to find a way to get rid of the chips/cool it/and make sure the feed rate is set correctly. We use the 1/8" mcmaster bits and we use compressed air to make sure the chips don't accumulate. Once you figure out the setup for your machine, you're all set and you don't have to play with it ever again.

We've used 2 3d printers, and while we liked one of them, we didn't think it was that useful. The first one we used was very temperamental, and would often get stuck or make a bad part. The other was significantly more expensive( > $10,000) and we couldn't seem to find a part that we couldn't make with a lathe, mill, and cnc router. Plus, the plastic was REALLY expensive, about $10 per cubic inch!