Wait times for machining

So recently our team acquired a waterjet sponsor and when I asked how long it takes to get material back, they said around 2 weeks. It appears to be a long time but I don’t know if this a long time to wait or if it’s reasonable since we’ve never had cnc capabilities before.
We do have a cnc plasma cutter, it’s a plasmacam (that’s what is says on the control box) and we’re in the process of modifying it to work as a cnc router as well as a cnc engraver. This should help reduce time but my question still stands.
How much time is reasonable for cnc waterjet/laser cutting/routing/ etc?

It depends on how busy the sponsor is.

Sounds like they have about 2 weeks of work stacked up at a time, which I would say is pretty reasonable in industry.

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Two weeks is not abnormal for the machining industry. However, if you build a good relationship with this sponsor, they may be more willing to squeeze your machining in between other jobs. This is the case with my team’s waterjet sponsor- they’ll get our parts back to us in about 5 days even when they have other work.

I hope you are taking into account your sponsor’s 2 week lead time when planning your build season. You may also want to build in some buffer time in case 2 weeks becomes 3 or 4. I recall seeing one of our local teams show up at a regional with a chassis with no wheels and no control system. Apparently, their sheet metal vendor delivered their parts the end of the day before Bag Day.

It just means you have to plan your season around that constraint. Two weeks is 1/3 of the build season (assuming you stick to the original 6 week schedule and don’t expand it with the new no-bag rules). It means identifying the parts you’ll need made early, creating CAD quickly, and getting the order in as soon as possible. If you have them cut parts for your drive train, then you won’t have the drivetrain done until week 3, at the earliest. How will that impact the rest of your activities?

When getting started with a sponsor that provides critical parts like this, it’s worth taking it slow. Don’t have them make every part of the robot. Start with 1 mechanism or a couple of difficult to manufacture parts. Grow the relationship and usage over the years as you gain a better understanding of the impact to your build.

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2 weeks isn’t a long time in business. But 2 weeks is an eternity during build season. When we had a laser sponsor we had 24-36 hour turn around time. I don’t accept anything more than that from potential sponsors in regards to build season. I let them know when talking to them about sponsorship that that is the turnaround I’m looking for and if they can’t meet it we’ll gladly take sponsorship in other forms.

That being said 2 weeks might be acceptable to you and your team and like i said its not a long time in the manufacturing business world.

Two weeks isn’t ridiculous depending on what the job is but keep that in mind during your build season. We’ve also let our sponsors know if we needed a tight turn around on stuff in the past. Sometimes if the parts we need could be nested easily with current work/machine setups they’d hook us up. Other times, we’ve been told no.

Ironically, this year we didn’t go to our primary CNC shop for any work so they assumed we had machining capacity if we hadn’t already been begging them for help. So, they outsourced another team’s gearboxes and drive train tubes to our team to make since their company was slammed with work. We got it done a 6-7 days faster than the CNC shop could for the other team.

@ProPain37 We were told 1-2 weeks by our sponsor. That’s just cutting aluminum sheet, no forming.

While we do our best to manufacture 100% in-house, about once a year we end up in a manufacturing bottleneck and have to request help from a local waterjet shop to relieve pressure from our CNC’s. Lead times are 1 day +/- 1. Two weeks is a lot, and certainly more than we could deal with.

Rules question: you aren’t allowed to use designs you haven’t released publically, and you aren’t allowed to use parts manufactured before build season. If you design your drivetrain in December, publish it, and then send it off to a Waterjet shop just before Christmas with a 2 week lead time for delivery on ~Jan 6, could you legally use those parts?

A two week lead time was typical for parts machined at sponsors when I mentored FRC228 while in college. As others have noted, two weeks is actually pretty fast for most items in the real world of contract manufacturing. Usually you’d be looking at 4-8 weeks at a minimum for most jobs.

Definitely in the grey area, especially since you may not know whether the supplier has stock material on hand (fairly atypical unless it’s cutoffs) or whether they need to purchase raw material, which usually has at least a 1-2 week lead time for common materials.

Hopefully if when we can survive the end of bag-n-tag this year without any major fiascos, we can remove the “no fabricated parts made before Kickoff” rule for 2021 season.

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1-2 weeks is about what we’ve experienced in the past with our waterjet sponsor as well. The owner of said sponsor company is related to one of our mentors too, so the time isn’t because they wouldn’t like to get us the parts sooner, it’s just hard to make it work with their production schedule, and they get us the parts as quickly as they possibly can.

That said, turnaround time can also be affected by post-processing, so if you specify that you ONLY want them to waterjet the parts and not clean them up after (deburring and such) you might be able to get them more quickly and do the post-processing yourself.

I’d say expect 2 week lead times unless:

A. It is a small & friendly job shop that you have good rapport with, and they have little Q4 and Q1 demand

B. The companies marketing team is very amendment about sponsor/team relations, and whips the order through production

C. You are a paying customer that also pays an expedited rate.

D. They can somehow nest your parts in with another order.