My team is in the US but I was wondering do teams ever have trouble finding inch based tools as opposed to metrics? I was watching 1114’s CAD video and noticed that they use IPS.

At least in the US, I think you’re much more likely to find tools and hardware in US Customary rather than Metric. We primarly stay away from metric just to keep finding parts as easy as possible.

1114 is Canada-based, so this may make a difference in choices. I don’t know if US Standard or metric is easier to find there.

In Australia most tape measures and rules have Imperial and Metric, and wrenches and Allen keys can be found in either system as well. Imperial fasteners are hard to find. We standardise on Metric where we can, but we still have to use Imperial when working with products like wheels, gearboxes, square tubing etc.

We have tried at different times to use all metric units in our code, but it feels like we are fighting a losing battle with both field measurements and wheels both being in imperial units, we generally give up and just take the path of least resistance.

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As an Israeli team, we standardize on metric everything. Metric aluminum, metric fasteners, metric programming, etc etc. Really the only time we use US units is the first day after kickoff before we translated all of the field dimensions into metric and when we need to use fasteners for FRC COTS items. Even then, a lot of times M4 fasteners can be substituted for #8, M5 for #10, and M6 for 1/4". When we do need to order US parts, they’re often difficult if not impossible to find. We actually had to set up a special connection with McMaster to get inch size parts shipped from the US.

217 was (is?) notable for designing in metric as much as possible, at least as recently as 2010 (not sure how long the practice continues or if it still does)

Standardization is really about making things easier to source. 3946 (except for fitting to COTS pieces) uses 10-32 and US customary coarse threads. I would fully expect teams in most of the world to do the same - fit to COTS where necessary, but use the parts easiest to source for everything else. I can personally vouch that it is difficult to source US/Imperial parts in most of the world, having traveled for the navy taking acoustic measurements.

Warning - the rest of this post is almost completely non-FRC story time for those who wish to skip it.

Trying to buy US standards abroad: Don’t try to get 2x4’s abroad - one ship I was on (USNS Kane) got a bunch of terribly expensive hardwood boards which had been custom cut to 51 mm cm by 102 mm. On the USNS Silas Bent we even had great difficulty buying ~20 gal mineral oil for one of our hydrophone streamers - we almost wound up buying about two hundred bottles of baby oil before some was located at a not-particularly-nearby US Navy facility.

ROFL! Gixxy, Pereichi and I were having this conversation about half an hour before OP - derived from asking how much firewood is in a cord and stoked by my interest (well known and appreciated by my sons) in units of measure. Where our conversation turned curious was in hybrid units. Gixxy talked about how in 2013 (Ultimate Ascent), our rangefinder to the goal reported the distance in millifeet. The US Navy reports ranges (distance to another ship) in kiloyards.

Perhaps even more curious, a traditional unit of measure, the nautical mile, was originally defined in terms of a speed defined by knots payed out in a rope tied to a log behind towed a ship multiplied by an hour. It is now defined to be 1852 meters exactly*. The original definition of a meter was 1/10,000,000 of the distance from the equator to the north pole, making the average minute of latitude equal to 1851.852… meters. Coincidence? I think not.

  • Which just happens to be 2 kyd to about 1%.

Edit2: Even stranger was about half an hour later (around the time of OP) when Pereichi asked what units the Egyptians used. I talked a bit about cubits and spans, which led to a discussion about pyramid construction lead by Gixxy. This lead to me volunteering that the Egyptians had a great approximation to pi by using a lathe or potter’s wheel and a piece of cord. Just a few minutes ago, I spoke to Pereichi and found out that it was actually curiosity about how the Egyptians calculated pi that lead to the question about Egyptian units.


We don’t use as much of it, but there’s a definite market in firewood here. The price of seasoned oak here is about $150 per **half **cord. This is likely because so much of the area is covered with loblolly pine; only the relatively high ground grows hardwoods (apart from cypress).

Speaking of ‘stoking’ interest - what is a person in LA wondering about cords of wood? Seem interesting to me as I burn wood to supplement heat in my home here in the Bold North of Minnesota - but in Louisiana?

By the way, a cord of seasoned White Ash or White/Red Oak here in my area goes for around $115-$150. What about the same in LA?

Oh - and yes, at 0 degrees (F) average temp the last week, I have gone through a lot of wood this last week which means I will be cutting the next two days before Christmas Break ends and Build Season begins!

Being in the US, IPS is a lot easier to find than metric. Metric bolts and nuts are fairly easy to get, but having a mix of metric and IPS on hand is risky. One will sort of thread onto the other with bad results. Metric stock, IE aluminum shapes, is hard to to find other here.
Cars and such are mostly metric fastener wise these days.

I don’t really know of any Canadian teams that standardize metric.

What sort of tools are you looking for? Many tools are agnostic. You should have no trouble finding both Metric and SAE (Imperial) wrenches and sockets. Most measuring instruments now switch between Metric and Imperial with a push of a button, even the cheap digital caliper from Harbor Freight.

You might want to consider using mixed units, and keeping them straight, to be part of your STEM education. Many products manufactured here in the US and abroad use a mix of components that have been designed to the Metric and Imperial systems.