Found a steel supplier near me, wondering which would be best?
Like the looks of the first 2, but not sure about the 3rd.
https://www.walterswholesale.com/1-in-aluminum-rigid-conduit-1-inch-x-10-ft-61401
https://www.walterswholesale.com/intermediate-metal-conduit-1-inch-x-10-ft-5231
https://www.walterswholesale.com/1-in-emt-emt-conduit-1-inch-x-10-ft-5398
Thanks 
The 23.5mm parts for the MPCNC fit 3/4" conduit, which is 3/4" inside diameter.
The 25.4mm parts are for steel tube, which is measured by outside diameter.
Iām pretty sure all these 1" conduits are not going to fit in any of them. You need 1" OD tube, not conduit. The 25mm parts are for tubes with an OD of 25mm.
Jeffe is right - these are all Conduit which is measured by ID not OD. Conduit is the thin wall gauge stuff that electricians run non-Nomex wire through, very different from Stainless Steel Tube. Conduit has much lower tolerances and strength then SS Tube.
This is an example of what you need: https://www.metalsdepot.com/stainless-steel-products/stainless-steel-round-tube Look at the T4R1065 version - itās 1" OD x 0.065" wall thickness x 0.870" ID. That size or the 0.120" wall thickness is the dimensions that we need for the LR2. As long as itās SS TUBE that meets those specs you will be ok. SS PIPE isnāt the same thing. Itās measured by ID and will be 0.05" out of spec on the OD for what we need. Some steel suppliers get confused between TUBE and PIPE - we have to have TUBE. Itās a small difference but itās critical for the LR2. That little difference means that PIPE wonāt fit.
Well, crudā¦ok
More places around me, but many donāt show great specs or prices on their site, Just call for a quote, which is really really really REALLY!?..great! ?
So Iāll have to spend some time dialing digits, and generally annoying a few poor people verbally, with my silly āYou guys got the thing I want huh?!?!ā questions.
Also, found this but again the specs are vague, so menothinkso.
https://www.mkmetal.net/steelrndtube1x.065x20
Thanks
This is correct in that it is Tube, but you REALLY want Stainless Steel. Normal steel isnāt corrosion/rust proof like Stainless is. Itās also been my experience with welding and steel work, that standard Steel isnāt manufactured to the same standards as Stainless. On that website, this is what I would get: https://www.mkmetal.net/304rndtubemirr1x.065x20
Interestingā¦
While that price and location is decent enough to bring her home to meet the folks, Iām still curious to know whatās wrong with her ugly step sister in the corner?
Assuming the 2 of them have the correct dimensions, is rigidity still a factor?
Or maybe the polished and buffed surface is the reason for the almost quadrupled price?
Would spinning her up on a lathe to sand and surface the outside finish help?
As far as corrosion and rust protection, would a thin coat of polyurethane solve this?
I know, I know, so many dumb questions. My username is to blame for this, or maybe itās the āvitaminsā those nice men in the white coats gave me? Nevertheless, Iāll stop now and go back to stareing at the wall,
Thanks!
Stainless has a different āformulaā then normal steel. Different amounts of the varying elements make Stainless very different from ānormalā steel. The cost differences comes in the different chemical makeup and the process to create it. The biggest difference is that ānormalā steel (also called Carbon Steel) is made up of Carbon, whereas Stainless Steel uses Chromium. Different Alloys of the steels contain different percentages, but Stainless generally has around 11%-12% Chromium in it. Stainless Steel is also harder and less Ductile then Carbon Steel (which is great for what we want, we donāt want the steel to flex or move).
One thing I donāt like about the M&K website is that they arenāt listing what type (alloy) of steel their Tube is. Makes me think it is low grade stuff and more likely prone to defects and not meeting specs (I could be wrong but itās something to consider).
Short answer - Rigidity is a factor, Stainless is more rigid and less likely to flex.
Iām not sure about putting polyurethane on it, never even thought of it, I just went with Stainless to save myself the hassle.
Kinda, sorta?
https://www.mkmetal.net/stainless-steel/alloy-304
Got a quote in their hopper, and asked for a spec sheet, weāll see what those MKMetalheads say.
???
?Thanks?
Iāll chime in here and say that itās not terrible to get non stainless steel. At least it fits. But if you can afford it, the stainless should be better. Especially if your LR is full sized.
The Stainless they do list as 304 (which is fine for what we do, no need to go exotic on it). I just wish they listed the alloy of the carbon steel.
As Jeffe said - you would probably be ok with the non-Stainless, but if you can afford it, go Stainlessā¦
Those MKMetalheads responded, seems legitā¦
1X.065 X 20FT 304 RND TUBE MIRROR FINISH = $77.66 + TAX. Good in stock.
304 Stainless is often called 18/8 or 18/10. This refers to the composition of chromium and nickel, which is the most important elements of 304 stainless. Breakdown is as follows:
[attachment file=94808]
Butā¦
Now in this corner, we have the reigning champion Cheap Bastard!!!..and in our opposing corner we have the part of the brain everyone loves to hateā¦Common Sense!!! Boooooo!!!
Ding! Ding! Round 1
POW!! Only a few seconds in and Cheap has made an illegal move with a swift kick to the groin of Common Sense. This might be all over folks!
So as soon as I can walk & stop talking in a high voice, will grab the cheaper version first just to see what kind of trouble this Kwyjibo can get into.
Either are not terribly expensive. So if I buy both and end up with an extra 20ā of tube, maybe I can bend the leftovers into a U shape and send it to Google.
Still wondering if the surface finish is a factor at all, and if sanding or polishing the steel will help smooth the movement during operation? Or will a mirror finish put me at a disadvantage by making my butt look big?
Thanky Spanky
Lol Spanky, I love your posts!
The finish on the steel shouldnāt matter too much if itās just the typical mill scale thatās on it. Any sever pitting or crustiness could be an issue though as the bearings need to roll smoothly over it. The mill scale actually prevents it from rusting so itās not a bad thing per se, but if itās causing the bearings to not roll smoothly or causing them to pick it up, then you will need to remove it, which can be a pain on round tube. Itās generally hard and thick enough that you need to grind/sand it off but doing that could also put flag spots into the tube. There are also chemical methods of removing mill scale, it you would need to google those as I just grind it off of the steel I work with.
Iāve gotten to the point in my life where I take the ābuy once, cry onceā philosophy. Iād rather pay a little more and get what I need the first time, then have to buy something over again. Thatās not to say Iām still not cheap (I still get a lot of stuff at Harbor Freight) but I also make sure Iām not going to be spending more money in the long run if I have to buy something twice.
Just food for thought.
Cheap Bastard, did you know you can make a pretty good tube from spaghetti? Individually, they arenāt very strong, but with enough glue, it will even make a bridge. Just be careful to not cook it.
Guysā¦ I thought Iād be better off asking this one here. From what I gather, the lrcnc2 bundle has enough belt for a 4āx8ā build. So, given those measurements (and probably less) how much ss tubing will I be needing??
Roughly 14 feet.
Does this tubing look suitable? https://www.amazon.com/gp/product/B072NZQF6V/ref=ox_sc_saved_title_5?smid=A1VCRSRWQX9LP7&psc=1
That should work.