We are applying for a grant for “advanced manufacturing”, and we’ve been asked to put together an equipment wish list. Our “Robodrome” shop has a few metalworking tools (lathe, mini-mill, band saws), but CNC machines are a whole new world for me, so I’m not sure where to start:
Which tools have the best capacity to our manufacturing possibilities for robots and side projects
Which tools have the best “bang for the buck” (including installation and consummables)
Which tools are the easiest to train students on (especially as we don’t have anyone trained yet)?
I know this topic has come up on CD before, but I thought I might take a more recent poll, since the technology is constantly changing. Can you comment on your experience with the any of the above candidates? Which is most and least useful? How much did you pay for yours? Do you have a vendor you recommend? Are there considerations I’m missing?
As for the CNC Lathes/Mills, I think Tormach would be an excellent choice for student use.
Yes, they aren’t HAAS machines, but not many students in HS are trying to hold a .0005 tolerance. That, and their spare parts are dirt cheap compared to HAAS.
We have on of these (http://www.cncplasmacutterinc.com/) plasma cutter router combo. We use mostly the plasma cutter for our HS manufacturing class. 4’x4’ water table. It takes time to swap out for router but it will perform reasonably well ± .005. We use inventor or sketch up to export DXF files. It came with a dedicated computer for around $13,000.
bang for buck if you want to non robot stuff too.
+easy to use
need ventilation
need large air compressor for plasma
Lasers… We have a older Universal laser 35watt I think. It will do a nice job of burning wood ( making plaques and such) but will never cut anything more than very thin wood. We use CoralDraw for our software. ** as far as i can tell a 60w laser will not cut any metal you could use for robots
+make neat wood burning you can sell
Easy to use
Will not do anything with metal
Lathe… for FIRST robotics a good manual lathe is almost better than a CNC IMO
3d printer… We have a Afinia h800 and like it Cost about 2k
CNC mill. this will be our next item. The one you are looking at seems good although I have little experience with Tormach. A HASS will cost a lot more.
If allowed by the grant, it might also be useful to use some grant money to build up your stock of tooling, fixtures, coolant, or even a stock of materials to train on.
I highly recommend writing letters to 3D printer companies before purchasing. (if you have students willing to) Many will offer additional educational discounts, or in our case, donate machines outright.
The best bang for your buck is currently the Prusa i3 Mk2 (250x210x200mm), but I’ve also had good experiences with the PrintrBot Plus. (250mm^3) If you’re okay with a bit of fiddling during preseason, the Monoprice Maker Select printers are excellent and only require minor modifications to become top level performers.
If money isn’t an issue, I would look into the LulzBot TAZ 6. (280x280x250mm)
It does use 2.85/3mm filament, so you probably won’t be able to swap from different printers.
As with any printer, I cannot recommend Simplify3D enough. Nearly everything can be tweaked to your liking and I’ve never had a print fail with it.
Edit: Octoprint or Astroprint running on a raspberry pi 3 is also super convenient, especially for printers that don’t have an LCD or touch screen interface.
Not sure of the amount of your grant, but here is what I would look at:
**
3d Printing/Additive Manufacturing**
I wouldn’t just get one, I would look at getting one premier printer and then 1-2 smaller printers for simple prototyping Stratasys
First and foremost I would look at getting a robust 3d Printer. Stratasys has a line (F123) that runs from $20,000-50,000 and are all incredible machines. We are currently looking at the F1 and it will be able to put out most of our projects. MakerBot The Replicator is an incredible machine, but it is a little pricey for the size of printing available. FlashForge
These are MakerBot Replicator knock-offs that run great. We picked up two of these and have been running them non-stop for about 6 months with few hiccups. They are limited in size and are pretty noisy.
Lathes w/DRO
Not sure if you need a CNC lathe as a lathe with a digital read out is a great learning tool. We have two lathes in our shop: Northern Tool(http://www.northerntool.com/shop/tools/product_200659733_200659733) that we picked up for $700. It works, but would not recommend. Grizzly Lathe Grizzly G0768Z - 8" x 16" Variable-Speed Lathe with DRO
Customer beware when purchasing Grizzly products. Almost all are Chinese made garbage and will not hold tolerances (from reviews). However, this one we purchased about two years ago and it has been incredible. We picked it up on sale for around $900 and has been great for making AM components fit VEX and vice-versa.
I am about spent as there is no way you will be able to pick up the other machines we have in shop as most are WWII era or older (all donated from sponsors). What I can say is that any machining equipment that you purchase is the first cost - the second cost comes in the way of clamping devices, mill ends, cutters, heads, etc. Make certain you price out each machine and the ENTIRE ecosystem that you will need to operate it effectively.
A bit of a warning about the newest Makerbots (Gen 5) from personal experience and what others have noted: they’re not the best option for the price. Even with the new redesigned extruder, there are still jamming issues that require human input to correct. If you start a 12 hour print to go overnight, you might be greeted by just 20% of a part the next day.
Without a heated bed, you’re limited to just PLA. (PETG might be possibly if you’re lucky) There’s also the whole “completely closed sourced with no user serviceable parts” thing, but that’s a different issue entirely.
The previous generations of Replicators are excellent machines and I wouldn’t hesitate purchasing one at a good price.
As noted, Stratasys machines are excellent, albeit a bit pricey. Of all the printers mentioned here, they will probably last the longest.
Edit: +1 for MarkForged. The consumables are very expensive compared to other FDM machines, but they practically invented printing with continuous composite materials.
For 3D Printers, I’ve had pretty good luck with my Robo3D R1+, they also have a few newer models that look pretty nice too.
For a CNC Router, my previous team got an 1000mm X-Carve from Inventables that worked fairly well for light-use applications. It’s more suited for wood and plastics (great if you need to cut large polycarb sheets) but it can be used to cut thinner (1/8" and less) aluminum at slow feed rates (and using cutting fluid). We made a few gearbox plates and some other things with fairly good results. That said, while the price is great, if we had had a bigger budget, I would have gone for a more ridged router (preferably with closed-loop control).
A CNC mill can manufacture 3D parts, and thus is far more capable than a CNC router. The issue with CNC mills is finding one with enough travel to handle a 30 inch robot side plate.
A CNC lathe would be pretty far down on the list. A decent 14x40 tool room size lathe with a BXA or CXA quick change tool post will quickly handle any FRC jobs. Experience, decent measuring tools, and tooling are more important.
Plasma cutters will melt aluminum, their really for steel alloys.
A water jet is faster than a CNC mill or router at cutting sheet. It can also cut finer details (tap hole diameters) since it doesn’t have a limited set of tooling. They are very expensive to purchase and maintain.
3D printing is almost a FRC basic need. Plenty of other recommendations here.
On the something else.
My favorite shop tool is a cold saw. It’s the best way to make very accurate cuts in any aluminum extrusion.
This really depends on what you’re using it for. Generally speaking I feel like FRC teams are mostly working with flat parts, and if you have a bunch of parts you need cut out of a large sheet, it can be much faster to cut it on router. Even on low-end CNC routers you get ~6in of Z-axis travel which is more than enough for most FRC applications.
The only real issue I have with CNC routers is that it’s difficult to mount any existing part to them to make adjustments or additional cuts to it, and have it line up accurately. CNC Mills are more suited to this process of clamping a part in, zeroing it manually, and then running your program.
IMO, ideally you’d have one of each, if you have the space/funding.
Incidentally, I also discovered (the hard way) this year that water-jetting polycarbonate actually makes it more brittle unless you stick it in a drying oven to get the moisture out of it. Very glad we had asked our sponsors to make spares of the parts we sent them.
A CNC mill with an X axis at least 30in long (a PCNC 1100 is NOT a knee mill, and as much as I like them (I have one in my garage) they’re not super useful for FRC-scale stuff)
On lasers, we are pretty happy so far with our Boss Laser LS-1630 with a 100W tube. It engraves slower than the US-made lasers, but it’s a fraction of the cost. We can cut 1/4" acrylic and 1" foam on it. Have not tried wood yet.
Seconding this. If you’re getting a 3D printer for FRC and $3500 is anywhere close to your budget, get this printer. The strength and quality of MarkForged composite parts is just completely unmatched, especially for the cost. It is well worth the higher price of consumables.
Third. If you’re not convinced enough, get a sample from their site. The stiffness of Markforged’s material in comparison to a ‘generic’ print is a selling point in itself.
I would hope so, considering the cheapest material they offer is more than 2.5x the cost per cm^3 of PLA or ABS (and their other materials are up to 15x more expensive). :eek: