Greetings! I am planning an LR3 build and was wondering if there are any advantages by going with 1" conduit vs 3/4" conduit for the X rails?
Assuming you are in the US, 1" conduit wont work. Its not 25.4mm OD. Go with the 3/4" I’m using it on a full sheet machine and its working great
1 Like
Much appreciated 
.
2 Likes
1” stainless steel tubing is 25.4.
Pros: much stronger, much less susceptible to getting bent
Cons: heavier, much more expensive
Edit - I have 0.12” thick tubes, you can get 0.065 thickness, which is less strong and somewhat less expensive, but either are stronger and more expensive than 3/4” EMT
Specifically, tubing is measured by OD, conduit is measured by ID. In the US, EMT is pretty well standardized, so even though it’s measured by ID, and wall thickness isn’t technically specified, it’s quite consistent.
Tubing (a structural material) matters how it fits into the structure of things (you’ll also find wall thickness a useful bit of info), and conduit/pipe (a transport method) matters how much stuff you can fit into it (although you can often find wall thickness as well, especially for pipe, where pressure may be an issue).
That’s how I remember it.
1 Like
Just to note that tubing strength really isn’t necessary for the Y rail, and probably isn’t necessary for narrower X rails, depending on what you’re cutting. Longer width X rails may (or may not ) benefit from using SS.
Note also that I’m a rookie at this, so @vicious1 may be able to clarify.
Just to be full-on pedantic, it’s not strength we’re after, it’s rigidity. Strength often involves a certain amount of flex, and you don’t want that. Granted, we don’t want it too brittle, but the key factor is stiffness, not strength, per se.
Yes, my meds ran out. But they’re in the mail… 
2 Likes
Welcome @Andrew_M ! How wide are you planning to build, what kind of materials are you looking to cut?
@azab2c I am wanting to do be able to do full sheets of MDF/Plywood, which brings up another question: Will the std 1400mm size handle 49" MDF, or do I need to bump it out an inch?
1 Like
Hey @Andrew_M, to do full sheet 49" MDF, personally added an extra 1/2" wiggle room, putting usable 49.5" into https://docs.v1e.com/lowrider/calculator recommended I cut 1440mm Struts (and 1440mm Pipes, however, if anything Pipe should be slightly undersized so Pipe don’t push/warp the plates attached to end braces).
Full disclosure… I’ve yet to cut full sheet MDF, but it’s nice having so much space on my ~2’x4’ usable everyday workbench that I can have multiple smaller projects tiled next to each other.
Am using cheap 3/4" EMT, which has been great. Knowing now how much I’d be using and tinkering with the machine, would’ve invested in thicker wall Pipe, especially for a full width machine. That said, cheap 3/4" EMT was a good choice back then when unsure how interesting this project would be. Am more likely to build another beefier LR3 gantry rather than upgrade my existing 3/4" EMT gantry, but not anytime soon.
Hope that helps!