Waterjet vs. Manual Build Process?

[Xifilzer]

Our team just recently completed our 3rd FRC Season, as a team we have adequate funding, a drill press, bandsaw, belt sanders, the whole ryobi handtool layout, dremels, etc. So far we have always used the machines in our shop to make our parts and only waterjetted or welded very few components such as sideplates (on a drivetrain).

For next year we are in a debate whether we move towards waterjetting more parts, and then assembling it, or if we stick to our current means which does also involve CAD before and during the build process.

The reason this debate exists is because we believe that waterjetting will give us more precise parts which will help us build a better robot, which means more awards, winning, which enables our team to get more money, have a better reputation, etc. But on the other hand we want to keep our current method because it allows kids to get close and personal with tools and encounter problems and learn really deep and intricate concepts when it comes to why mechanisms work, forces, etc that simply cannot be taught via simply assembling a robot. We also believe that our current method is more fun, even though the final product may not be something similar to the high quality of a NASA team.

Please give us your input regardless of which side you stand on, we would like to hear whatever you guys have to say!

Thank you for your time,
Sincerely,
Xifilzer

[macman828]

Originally Posted by Xifilzer

Our team just recently completed our 3rd FRC

The reason this debate exists is because we believe that waterjetting will give us more precise parts which will help us build a better robot, which means more awards, winning, which enables our team to get more money, have a better reputation, etc. But on the other hand we want to keep our current method because it allows kids to get close and personal with tools and encounter problems and learn really deep and intricate concepts when it comes to why mechanisms work, forces, etc that simply cannot be taught via simply assembling a robot. We also believe that our current method is more fun, even though the final product may not be something similar to the high quality of a NASA team.

The fact you are having this debate within the team is wonderful. What I expect you will find if you go with more waterjet parts is that you will find something else to have fun, teach kids on. Your robot isn't going to be just flat pieces of metal. it has to come together. You'll need to tap many holes, or riveting, you'll end up bending metal too. You will not run out of fun things to do and new things to learn. Either way good luck!


I'm sure CD will be filled with comments on awards / NASA teams etc. etc. just focus on what your kids want to learn, what they will have fun with.

[RoboChair]

Buy a CNC router.

Zero regrets.

That is all I have to say.

[jnicho15]

Originally Posted by RoboChair

Buy a CNC router.

Zero regrets.

That is all I have to say.

What make/model? Our team is considering "joining the club" this off-season.

[RoboChair]

Originally Posted by jnicho15

What make/model? Our team is considering "joining the club" this off-season.

4'x4' bed router, 1678 has been wonderfully impressed by our VeloxCNC Router that we bought last October. It was so good to us that we hardly used our CNC Laser sponsor, pretty much just some gussets and our belly pans(made 3 robots). That one machine made easily 75% of each of our 3 robots this season. Far better than the one I have at work, I'm jealous. PM me if you want to know more about the exact options.

[Fusion_Clint]

Originally Posted by RoboChair

4'x4' bed router, 1678 has been wonderfully impressed by our VeloxCNC Router that we bought last October. It was so good to us that we hardly used our CNC Laser sponsor, pretty much just some gussets and our belly pans(made 3 robots). That one machine made easily 75% of each of our 3 robots this season. Far better than the one I have at work, I'm jealous. PM me if you want to know more about the exact options.

Ditto, We purchased a 50X50VR Velox last year with a 2.5 HP HSD spindle and we love it. We have no problem machining 6061 aluminum.

We made our 2016 robot completely in house (classroom) with our Velox CNC router, AirWolf 3D Printer, and Jet Lathe.

[Kevin Leonard]

A few notes.
CNC or Waterjet equipment is NOT NECESSARY to be competitive. 5254 was highly competitive the past two years despite using almost exclusively COTS parts from VEXPro.

However, these things can be helpful if used right, and provide a huge learning opportunity for students, especially if your team also uses CAD heavily. I vividly remember seeing our 2013 shooter plates on 20 being waterjetted using RPI's waterjet, and it was inspirational (and effective as well).

Advanced manufacturing techniques are not necessary to build a good robot, but they can help make some difficult tasks easier and provide a unique learning experience for students.

[RoboChair]

Originally Posted by Kevin Leonard

A few notes.
CNC or Waterjet equipment is NOT NECESSARY to be competitive. 5254 was highly competitive the past two years despite using almost exclusively COTS parts from VEXPro.

I 100% agree that they are not necessary. Our 2013 robot was built in a 20' shipping container with a tabletop mill, a small amount of outsourced mentor machining, and a box of scraps; made it to Einstein. 2014, same container, added a Bridgeport mill and a Harbor Freight mini lathe, nearly beat team 254 for the World Championship Title. 2015, actual shop space with reasonable manual machines, all CNC parts outsourced to sponsors, won Champs. Needed, no, but it can make life go smoother some times.

[adciv]

I've got a few different views on this, mind you I'm from the programming side of the house. Also, waterjet/CNC, consider what's more appropriate. A waterjet is nice but may require significantly more maintenance and upkeep than a CNC. Look at the sustainment costs for each before deciding. I think a waterjet starts at $80k, if you can get one for significantly less please tell us.

1) On the loss of hands on. I've had some debate with one of the other mentors on this who thinks everything should be done by hand. In the real world you will not be cutting everything manually. In fact, you would likely be fired for attempting this. It's not always worth it to build everything by hand or from scratch.

2) You don't have to give up hand cutting entirely. This year about half our robot was hand cut (or could have been, would have to check) and half was waterjet/CNC. Our main frame was box tubing and wood ribs. A few pieces were water jet and bent with a brake. One of our components was right angle aluminum and was hand cut with a hack saw. Determining which is the most appropriate method is another part of engineering (I can build this and it costs X or I can go to home depot and it costs Y).

3) Beware the CAD Trap and Prototype. One thing we've sometimes become trapped by is the design trap of trying to get the robot fully designed and then building it. If we came across an issue, sometimes it would be too late into build season to fix. Hand building can be easier if you don't have as much of a delay for prototyping. Our original drive train this year got stuck on the moat and we did a quick redesign to fix it. This wouldn't have been as easy in years of heavy dependency on CNC/waterjet where we send the components out for manufacture.

On a different note, if you don't do it already I recommend you build a practice robot in addition to the competition robot. If you do, try to build the practice first and use it for prototyping, programming, and learning how to build the competition robot. Your programmers will thank you and the build quality of your competition robot will greatly improve.

[BeardyMentor]

My day job is implementing an integrating CNC and other computer based manufacturing techniques in existing manufacturing processes. The correct answer here is; Do what works for you. Some parts the only way to make them is to have them done on a 5 axis CNC. Others, can and should be done with a drill press and a jigsaw. It depends on complexity and the tools and skills you have on hand. If you have easy access to a waterjet, use that. but if you just need a rectangular spacer with a 1/4" hole roughly in the center, a waterjet is overkill and the set up time will be longer than just using a drill press. For each part spend a SHORT period of time evaluating your options and use what makes the most sense.

I guarantee you that not every part can be made with the waterjet and some handwork is going to be required anyway. There will be plenty of hand work no matter how much stuff you get made on some flavor of CNC.

[Gdeaver]

Water jetting is wonderful if you have a local business that will help. We design in Solid works. It wasn't free. We spent about 400$ total on water jetted parts. It was well worth the budget. 1 day turn around as apposed to days and days to make them in house. The smaller parts - gussets, shaft adapters, motor mounts and other plates were done in house with a X-carve router. Last year we held classes teaching many students cad and design. This year over the summer we intend to cover cam with Hsm express. We are going to have a project with the cad cam and mechanical teams to design and build a 3d printer. The goal is to ingrain modern manufacturing methods and the maker mentality in the team and get away from the tedious hand crafted robot parts. It does take money. Find sponsors and fund raise. It's easier to get sponsors when you bring them in on a busy build night and they see kids hunch over the lap tops cading and the cnc stuff running full tilt. Of course there is always those parts that need careful hand crafting.

[Tottanka]

Could you give some input regarding a suggested CNC router for FRC use?
It has to be safe, big enough for FRC and easy enough to use with Solidworks or other CAD software.

Thanks!

[Joseph Smith]

My team did some water jetting for the first time this year, and we've done a few laser cut parts in the past too. When it comes to designing a part to be water jetted, it takes a different mindset and set of skills. I believe that students can learn a great deal during the design process for these parts. We tend to find a balance between sheet metal parts and manually lathed/cut/drilled parts that keeps our fabrication team busy and engaged but allows us to go for the more complex designs. I think that there's still plenty to learn about the sheet metal forming, bending and assembling process, and still plenty of hands-on fabrication work that goes along with it.

[ebarker]

There are merits to making parts by hand and to CNC techniques.

I think for our team, the approach we will stick with is to have team members spend time in the off-season learning how to hand make parts, and then during the latter part of the off-season and into the build season, then transition into designing parts in CAD and then water jetting them.

I can tell you from experience that if I owned a business that made stuff I'd have the employees CAD the part, then CNC it. It is a much faster and more accurate process ( if the CNC machine is available ). But again I think hand made parts are more of a rite of passage and learning. But not good for production work. Brackets that would take us an hour to make and not be accurate, we can CAD and cut in minutes, perfectly.

For fun, maybe your team may want to take both approaches simultaneously.... making handmade parts and CNC parts, in parallel. The resource is available to you and your team. If you want to follow up to learn how to access this resource, send me an email at edbarker@kennesaw.edu

It would be fun and educational to make parts both ways. I think it makes your student a better engineer.

This summer we will announce some workshops at KSU where you can come in and give it a try.

EDIT: right now you can bend parts on this brake Hopefully we will get a 50 ton CNC brake soon.

Good Luck with your team !!

Ed

[InFlight]

For teams that use extensive CAD, water jetting is the way to go. You will have identical parts for your competive and practice robots. You can also have spare parts that will fit exactly.

Cadding the entire robot takes time in the 6 week build season. Rapid manufacturing balances out this initial investment in time.

We still use a lathe & mill to manufacture drivetrain parts, and intake rollers etc. so we have lots of opportunities to teach interested students those skills.