I have ~20’ of (free!) 29.5mm outer diameter steel EMT. Looking up EMT sizing (e.g. here), it looks like standard 1" tubing. Reading the first line of the Bill of Materials it says:
There are 3 different sets of printed parts C-23.5mm, F-25mm, or J-25.4mm (1in).
25.4mm?! How come my 1" conduit is 29.5mm OD? Now what... are the design files available anywhere so I can resize for the outer diameter?
Edit: Reading on, I guess it’s just a difference in how things are sold? In the US maybe it’s inner diameter or there’s just no consistency anywhere? Subtracting the wall thickness, I still don’t get 25.4mm for an inner diameter.
I do not have any CAD files available other than a few mounts that makes it easy for anyone to edit. I do this intentionally. I hope no one takes this the wrong way but the parts are easy to replicate. If you can replicate the parts from scratch you can probably make an informed edit and understand how the pieces interact and how to keep them printable as well.
I understand your frustration but it is mentioned several times all over the site, 1" is not for conduit it is for Stainless steel (a few countries have 25.4mm OD conduit). There is even a video linked on the parts page about this issue. Check what size your 3/4" conduit is. From the first lines in the parts page.
Please measure your rails before printing. 23.5mm fits 3/4″ EMT conduit in the US. Anywhere else you must physically measure first, some things are sold as Inside Dimension (ID) (conduit), or Outside Dimension (OD) (Tubing). Bummer
Steel hardware store EMT conduit works well and is inexpensive, an upgrade would be .049″ wall thickness stainless steel tubing (or thicker is fine as well). Stainless Steel tubing is more rigid and smooth, but also much more expensive.
Instead of getting upset I do not supply you with CAD files have a look around for either conduit, or tubing in one of the three sizes. We are about to hit the 4 year mark now and these three sizes seem to have the entire globe covered. I understand what you have is free but it is actually one of the least expensive parts of the build, $8 for me locally.
First off, I’d like to thank you for taking the time to respond despite my post coming across as upset. I meant that more tongue-in-cheek (hard to convey tone on the internet), I’m sorry that you took that as frustration as that was not how it was intended. I’m not frustrated, I’m just starting to pull together the parts for a build and was hoping to start printing tonight. I was anticipating what I had on hand would be usable, as it seems plenty strong and, as mentioned, it’s free.
The last 30 minutes of shopping have been particularly enlightening for me. I didn’t for a second consider that “pipe”, “round tube”, and “hollow round bar” were different things, and my ignorance led to my confusion. I posted because I had measured the rails before printing - so at least I got that part right? I had watched the linked video previously as well.
For anyone who reads this, at least in North America:
pipe is generally sold by inside diameter (generally used for fluids, so ID is the more important size)
tube is sold by outside diameter (generally used for structural pieces, so OD is the more important size)
conduit, or EMT (electrical metal tubing) is a tube, but as things run through the middle it seems the inner diameter is the critical dimension. Because it's neither a "true" tube or pipe, the industry appears to have come up with another metric "trade size" which seems to be neither inner nor outer diameter, which makes a mess of everything.
For example, metric trade size 27mm (1") EMT has a nominal OD of 29.5mm and ID of 26.6mm. It seems to be sold as "the closest integer to the the inner diameter"
Instead of getting upset I do not supply you with CAD files have a look around for either conduit, or tubing in one of the three sizes
I'm definitely not upset, I was surprised by this though. I read in the FAQ:
I am trying to keep poorly made things from popping up everywhere. It happened in the first few months of the release.
Have you expanded on this anywhere? As you provide the canonical source, were you seeing people ripping off the design and making modifications that were undesirable? I just cracked open the STLs to see what it would take to modify things (with my amateur CAD skills) to fit my 29.5mm tubing and it's definitely hours and hours of work (that you've already invested likely a few hundred times over). I'll likely do so for some pieces to use what I have, but I was surprised given how open you are with everything else.
That’s is just it, it is not one thing, it turns out every single piece needs to be modified, and turns out a tiny bit matters (25mm and a 25.4mm). I really can’t give you specifics here as I do not want to hurt anyone’s feelings but yes you can find parts that should not be used. The quote of mine you used is specifically referring to people sticking my stl’s together and printing them with support. This thinking is one solid piece is stronger, when in fact it is far from it, FDM printing is directional. The bottom corners and locks pop up combined all the time…they are made in two pieces for a reason.
As always I encourage you to try it my way before any modofications are made.