1" DOM 0.188" wall question

Mostly Printed CNC - MPCNC Advice
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Hi all, new member here from Central IL currently in the planning stages of a MPCNC. Prusa i3 MK3S+ is pending delivery this week and I’m excited to get it up and running and then printing parts for my MPCNC. Planning for a 24" x 24" working area.

My question is on tubing thickness, SS is not readily available in my area without a big MOQ. I can find 1" DOM 0.188" wall pretty reasonably and I realize that should improve stiffness (albeit pretty marginal), I’m curious if there is anything to be concerned of with the size of my machine and inertia of the additional mass swinging around on the gantry? Would I be better off using 0.125" wall on the Z axis only for the nut traps? Stay with 0.188" and modify the nut traps on the Z?

Thanks in advance for the assistance!

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You’ll be fine, get what you can!

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Thanks Ryan, I figured as much but wanted to see if there were definite NO’s. I’m on the fence about trying to go bigger on working area say 1/4 of plywood so 2’x4’. but if I start with 2’ x 2’ I only need a couple rails and some more belt to make it work. So I need to use your advice and start small and expand if and only if I need it.

Well my Prusa showed up today so first things first is to get that up and running, than start printing MPCNC FILES!!!

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Hey FWIW, I am using .125 DOM on my rig, and it is solid as F! Since you will have so much less deflection with the skookum pipes, you might also think about printing your parts with extra walls to match.

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Can you share where you sourced the DOM?

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I got it locally (in Sacramento) from a place called Big R Metals. It was something like $80 for like 27’.

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I also sourced it locally (Central IL). 21’ cut to length per the cut list calculator on the site here was just over $100 for 3/16” wall

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I found this Shop searching for SS tubing. I just received it today. Came perfectly packaged and in great shape. Much less than my local metal supplier.

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I ended up ordering from JEGS. 1" mild steel tubing w/ .083" wall
Bought 6, 48" lengths and well, while the price was not bad, if you are considering plain carbon steel tubing instead of Stainless Steel, and want to give them a try, make sure to call and talk to customer service, get a commitment for some kind of protective packaging and do not under any circumstance allow them to ship FedEx.
Straightness is a bit of an issue so buyer beware. How straight is straight enough? After doing some DIY pipe straightening, I got them all under 0.1mm out of perfect over 48" so I’m thinking they’ll be good enough. FedEx turned one into a hockey stick but JEGS shipped a replacement no questions asked. Oh, and FedEx totally lost another of the original 6 pcs somewhere in Grove City, Ohio.
If there is a next time I will reconsider and maybe drive there.

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Can you share your total cost delivered?