Australian tube options

Yes. Clearance issues between the bearings and pipe in “middle” assembly. You will see what I mean when you get it assembled. It was only “just” touching, so you may well be able to tweak the bolts to get an extra clearance. I didn’t have success.

Please let me know how you get on. It would be great to know if 25.4mm tube is still a viable option.

FYI. The alloy tube I linked ends up being less than $4.50 per metre if you buy a full length. Cheaper than the bunnings tube you listed. But as you have already purchased the bunnings tube I understand not wanting to buy tube twice.

Good luck with the build. Looking forward to seeing how it turns out.

Justin.

Happy to report that the Bunnings 25.4mm tube works fine.

Middle Z assembly clearances are less than 1mm but no contact between Z axis tube and bearings or bolt heads.

Note that the bearing bolt holes in the Middle_Joiner and Middle_End parts are slightly offset from center. The Middle End parts can be turned around (print bed side facing outwards) to gain a little more clearance for their bearings.

I found it very important to make sure the Z axis pipes are exactly parallel (i.e the same distance apart at top and bottom). I spent a little extra time sanding the tube holders in the Z_Motor_Mount in order to get them perfect and achieve very smooth Z axis motion.

I also made a drum sander for my battery drill to aid in sanding the tube mounts for a good fit.

Awesome! Good to hear. Thanks for the heads up mate. Sound like the build is coming together nicely. Great advise there for others who are starting their builds.

I ended up using a combination of stainless (I already purchased a 6m length after all) and the alloy that I linked. In the end I used stainless for the frame, and for the gantry. I had intended on using alloy for the gantry as it was much easier to push into the ‘middle’ assembly, but after some experimentation I opted for the stainless. It was tight to force into the middle assembly, but that extra tension made the completed gantry much stiffer, and only added a small amount of extra drag to the movement of the x and y axis.

For the z axis I used the alloy because I was still having clearance issues, it was lighter and I saw so difference in stiffness with the larger stainless tube. I am planning another smaller MPCNC for alloy, and intend on using the left over alloy tube for that. I’m also printing the next machine in Taubmans 910 alloy filament for additional strength/rigidity. http://www.taulman3d.com/alloy-910-spec.html Apparently there is a small about of shrinkage to take into account with this filament so I’m hoping the slightly smaller od tube will help there.

Cheers
Justin.

another down here in OZ (Melbourne) putting together this quality project, slowly printing parts and collecting hardware… should be ready to start assembly in the next few days…
after a few calls to local steel merchants, found this place selling aluminium 25mm OD 3mm wall 6.5m length for $40 cash… and they were happy to cut for free
Action Aluminium
they are located in Vic, NSW, and Queensland…
every other place I rang only had 25.4mm, still stuck in the imperial days…
anyway, happy building to all…

Hey everyone, just another Kiwi here looking to start getting stuff together for my build.

25mm OD stainless tube appears to be completely impossible to get hold of, so far. I’ve had one company that says they can get it as a special indent, but they weren’t even keen to give me a price due to the fact that it was ‘ridiculous’. Their price for 25.4mm was a couple of hundred dollars a length, so I let it slide.

3dTI - How are you finding the anodized aluminium? That’s the only solution that I’ve found so far that seems like it might come out reasonably. Looks like you must be getting a massively deep discount of list price, there. I came out at $70 for the 5M length from Mico Metals, haven’t checked with Ulrich yet.

A 25.4mm version (sadly) or 26.7mm (standard OD for 20mm nominal pipe) version would be the way to go for us, it seems. 26.7mm OD would have the advantage that galv steel tube is easily and cheaply available in multiple wall thicknesses ranging 2.0mm to 4.0mm, which would allow for things like heavier wall tube on the stationary parts and lighter walled tube on the dynamic parts.

Hi Jono.

The 25mm alloy from Ullrich aluminium (new Zealand company?) is still the best solution I have found. It’s cheap, rigid, incredibly accurate, and the surface finish is more wear resistant than 316 stainless!

I am in the planning stages of two new MPCNC machines. One very small, parts printed in PETG, and one very large (1200mm*2400mm) parts printed in nylon. Both will be constructed using the alloy tube.

See my previous post for exact details of the Ulrich tube.

Good luck with the build. I look forward to seeing how it comes together.

Yeah, I’ve dealt with Ulrich a few times. We’ve used a bunch of extrusion and sheet through work, although we’ve never bothered getting accounts set up (too hard to convince the lawyers) and I don’t know anyone there so no chance on getting anything below list price, unfortunately.

Have you got any machines running with it currently? It’s not actually wear that I’m worried about, as I think that will be minimal with the bearings running on it. It’s more the actual peening over of the surface with time, basically the material under the coating cold-forming into flats. We have some big equipment that uses steel cylindrical rails with hardened steel rollers and it has had the same effect, i.e. flat spots wherever the wheels run. That’s with multiple tons of pressure applied by big springs etc. though.

Given that it’s my only option so far, I think I’m just going to run with it for the moment.

Waiting on the hardware kit at the moment and the 3D printer is running away merrily with the other parts. Just finished my longest print ever, all 4x Roller F parts in one go, 30 hours total and 52m (~400g?) of filament. That marks the halfway point for the printing, by weight.

Just got a quote from Ulrich for $80 for the extrusion. I called around a few places and it looks like $50 if I want normal anodizing (12 micron) or between $150 and $300 if I want the parts hard anodized (25-100 micron, depending on supplier).

So yeah, any idea which type you’ve got? The regular anodizing keeps the cost much more reasonable, but it’s a false economy if it ends up giving the rails a limited lifespan. The hard anodizing is probably what I’d go for with no further information given that I want to be able to load the machine up a bit, if possible, but at $250 for the rails that’s heading rapidly towards the cost of a set of linear rails for a gantry type system…

What lengths for those dollars?
Are they going to cut the lengths for you?

The quote was for a 5m length of the 25mm diameter, 3mm wall tube, in what I think was 5005 alloy. Normally they will cut ‘roughly’ to length to help with delivery, but won’t do accurate cuts without charging an extra fee per cut. We normally get them to cut in half or thirds and typically it’s +/- 25-50mm on the lengths they cut to. I was going to get it delivered as 2x half lengths and then cut to 6x ~700mm and 2x ~300mm with our mitre saw and a carbide tipped blade.

The anodizing quote was for 7 pieces at 700mm long per piece for simplicity. The 4 places I contacted all appeared to quote significantly differently (per ‘ladder’ of racked parts, per part, per job but it all came out roughly the same).

Ok thank you.
Build it let us know how it all feels.
I got some electrical conduit that I thought was fine but turned out to be 24.6 :frowning: so to much slop

Doh, that sucks.

I think I’ll just be going ahead with the regular anodize for the moment and living with the $130 for the tubes + anodizing.

Hopefully the hardware kit will show up soon and I’ll be able to post some more in depth info.

Hi Jono.

Sorry for the late reply. Kids, study and work had sapped what little spare time I’ve had.

The surface finish is some sort of hot dip I think (AN 5-7um BRIGHT DIP CLEAR) is what is on the invoice. I really cant see the machine exerting enough force on the tube to deform the alloy (plastic parts after all) and the alloy tube in my current MPCNC is still in perfect condition (the surface of the tube is barely marked) after perhaps 20-25hrs run time so far.

I have other issues to contend with. The abhorrent weather conditions we’ve been having here have melted/deformed all the parts of my current MPCNC to the point that it unusable for any real milling at the moment. I have been playing around 3d milling some high density foam for learning purposes while I reprint my parts in PETG.

That is an epic print time. 31hrs straight is ambitious! Kudos. May I ask what printer you use? Nozzle? Layer height? I’m reprinting my PETG parts at 0.2mm layer height, with a 0.4mm nozzle… My K8200 prints very nice parts after all the upgrades I’ve done, but it is very slow. One roller F takes about 8hrs with my current settings.

Hi 3dTI,

No worries, thanks for the response. I should have followed up that I found all the info in your original post, sorry.

I wasn’t able to immediately line up what form of coating that you had with what they were offering but I found out from Ulrich that they have a couple of separate anodising companies that they use locally. They basically just hand the work out to them on a case by case basis, which would account for some variance in the finish. Both of those quoted for 12.5u anodize or 25u-50u hard anodize. The AN on yours sounds like anodised and 5-7um would be quite a light anodize. The bright/clear is probably just that they didn’t do an etch to make it matte finish and then didn’t add a dye before sealing after the anodise.

That’s a good result that you can’t spot anything after 20-25 hours, that’s what I was trying to get a handle on. I see what you mean about the force exerted, but it’s always going to flatten out some amount. A perfectly round tube with flat rollers ends up with ridiculously high point pressures for not much force. The equipment that we’ve got at work had roller tracks that started at ~1mm wide on a piece of 75mm steel tube and then widened out to probably more like 5-6mm over time before settling. I assumed something similar would happen with the aluminium but it should be an exponential drop-off, so if you can’t see anything then I’m 100% happy.

I’m assuming your parts were originally PLA and the temperature got up enough that they started to go soft? Man, that sucks… I was worried about that here to start with after coming from ABS-only printers but I’ve had no issues at all, thankfully. Very interested to know how you get on with the PETG, I have absolutely zero experience with anything outside PLA/ABS as they were the only options when I got started, but it seems like the alternative filament is turning into quite the industry, now!

The printer is a Mendel90 by nophead, built from a 100% parts kit about 3 years ago. Everything is stock apart from the addition of a raspberry pi running Octopi/Octoprint for control. It’s using a Wade’s geared extruder with a 0.4mm J-head nozzle and I normally use 0.3mm layers onto a heated glass bed. The printer has been an absolute workhorse. I’ve never had a failure with it in probably 10-20kg of filament. The usual teething issues with bed adhesion but getting the first layers above the Tg for the filament and keeping it clean with Isopropyl seems to be the combo that works for me. I’ve been using filament from Diamond Age here in NZ, as well. They’re actually just down the road from where I live and I think their quality is top notch. They’re definitely on the more expensive end of the spectrum, though, but given that I think I’ve only just passed the point where I’ve spent more on filament than on the printer, I don’t think that’s too bad.

The project I originally bought it for was something that basically used the entirety of the 200x200x200 build space for some parts, so I wanted something that was going to be minimal tuning and extremely reliable under long prints. I’ve been extremely happy. After that long print I just wiped down the bed and fired it up for another 20 hour one. It current did 14 hours overnight and has another 5 hours to go on the 4 middle pieces.

My hardware kit arrived yesterday, so I’m going to just go ahead and order the tube today with the regular anodise and see what happens. I’ve still got probably another 20-30 hours of printing before I can start assembly so it’s all coming together nicely.

Take some pictures as you go to keep us all inspired :slight_smile:

I’ve made a build thread to put some pics up and stick with my random musings so far. There are a couple of photos of the printed parts that I’ve got so far, Kawobei. Hope you like the colours!

I’ve picked up 3x 2.5m lengths of the Ulrich UA1248 25mm diameter, 3mm wall aluminium and done some chatting with an anodizing company to figure out the cheapest way to get it all done.

If I was approaching this from the perspective of trying to cut the costs slightly, I think my approach (given the relative flimsiness of the aluminium now that I’ve got some in hand) would be to try get all the aluminium cut from one 5m length. Assuming that the highest Z height puts the bottom of the rail at 25mm above the base of the corner blocks (rough guess based on the render showing on thingiverse) and a spindle+tool protruding 50mm from the bottom of the tool holder piece, I think I’d end up with for the following dimensions:

7x 620mm pieces to get anodized (2x X rails, 2x Y rails, 1x X carriage rail, 1x Y carriage rail, 1 piece to be cut in half for the Z rails)
4x 140mm pieces for the legs
Assuming 5mm wide kerf (roughly what our chop-saw does) then that pretty much perfectly eats a 5m length (or 2x 2.5m lengths)

Resulting machine would have a working area of:
X/Y = 350mm
Z = 110mm

Obviously the Z can be shrunk by cutting the piece allocated for the Z into less than halves, but this is just the ‘largest’ machine I think you can make from a single 5m length, paying attention to the anodising requirements. This also doesn’t make as much sense if the anodising company doesn’t mind working with different length parts, but this is based on the couple of companies that considered the different lengths different parts and were going to charge different for jigging up each.

Don’t know if that musing will help anyone, but figure it’s worth dumping somewhere.

Hi, I’m exploring a MPCNC build, and looked into getting some tube in Australia. I found one place that said they could do it. I haven’t followed up on wall thickness or cost:


Hi Marc,

Thank you for your enquiry. We have both sizes available. How much do you
require and where are you located?

Cheers,
Luke Tonkin
National Sales Manager
All Things Stainless

P: 0414 266 624
F: (02) 9475 4336
E: sales@allthingsstainless.com.au
W: www.allthingsstainless.com.au

-----Original Message-----
Sent: Wednesday, 25 May 2016 2:06 PM
To: sales@allthingsstainless.com.au
Subject: All Things Stainless: 3/4" tube

This is an enquiry e-mail via http://allthingsstainless.com.au from:
Marc Kelly

Hi, can you supply 3/4" stainless tube? Or 25mm?

Marc

Hi tortfeaser, I see a Sydney phone number, which part of Sydney are you in.

I went with the Stainless Steel 25mm OD tube, and found it to be very accurate along it’s length. The wall was 1.3mm and over the length of 875mm, I have no deflections.

The stainless is very expensive though, and I think If I built another MPCNC I would go the Aluminium Tube with 3mm wall.

Cheers
Greg.

Hi Greg,

I’m in Canberra. I’ll look into Al, for sure.

For what its worth, I got some more info from that supplier. I asked for details and prices for 7m of stock (I thought I’d like a machine that could do 900 x 600, though 1200x600 would be better).

I’m not sure how 1.5mm wall 3/4" stainless tube will go on a machine with a 1200mm side.


Hi Marc,

Both sizes are a Mirror finish and 1.5mm wall thickness.

Option 1: ¾” Stainless Steel Tube
7m x ¾” Stainless Steel Tube @ $18.55 = $129.85
1 x Delivery @ $25

Total including GST and Delivery = $154.85

Option 2: 1” Stainless Steel Tube
7m x 1” Stainless Steel Tube @ $18.80 = $131.60
1 x Delivery @ $25

Total including GST and Delivery = $156.60

Marc,

In those quotes, they are both imperial.

You need for them to quote you on metric size. 1" is 25.4mm, so that is too large in diameter. The 3/4" would be much too small.

They need to quote you 25.00mm OD Tube and 1.5mm wall. The 1200mm would only be approx 1 foot longer then what I’m working with, so it should be fine with that wall thickness. But it down come down to what you will be using the machine for!

Cheers
Greg.