Drylin Linear Guides

Hello everybody,

since the X-Rails of the Prusa Mendel and Mendel90s I have worked with got sticky from the heat of the heated bed, I have been considering to use plastic linear guides from Igus for my own build.
For that, I plan to use a heavily modified and beefed up Prusa i3 frame, completely exchanging the standard 8mm rods with various Igus products, most likely from the drylin N and T series. The printer is designed for maximum stability/rigidity so that it may also mill light materials like wood and plastics.

What I know is that some builds use the N27 miniature linear slides, achieving good looking results (at least the Cartesio one, the 3D Kit F doesn't seem to have sample prints). This by itself already seems promising, but when I visited the Igus site and used their service life calculator, the results were...not so great.
Maybe I am a little bit demanding, but no matter what system I choose, the play at the center of mass is always 0.1mm, even for systems with adjustable play in new condition.
For the next calculation, I used the Drylin N27 rail, for which you can find the config attached. Just load this into the service life calculator in the drop down menu to see which values I entered. The parameters I entered apply for the Y axis.
After 30,000 km, the play is supposed to be 0.4mm (I suppose I can still re-adjust the whole system to account for play, though). Now 30,000 km per axis sound very much, but let's calculate how many prints this would make:
Supposed a print needs around 50,000 double strokes per axis (pulled this value from here (Traumflug's second post)) and the build size is 150 mm in each X/Y direction, we get 50,000 * 300 mm = 15,000,000 mm or 15 km.
30,000 km / 15 km = 2000
So after 2000 prints, the linear guide is significantly worn out (without calculating in some safety margin) and after 2250 prints or 33750 km, the wear limit is reached.
If I were to print 3 parts per day, every day, these rails would wear out after just two years. Igus by the way also offers replacement plastic pads, but I could not find these on their site.
For the X axis this looks far worse because I cannot use multiple carriages due to space constraints, and the drive system is not as neatly aligned with the rails, so the wear is significantly higher.
Also, I have already contacted Igus about that and am waiting to hear back from them.

Ok, this is all theory and highly hypothetical, so I would really like to know how your real life experiences are with the Igus products. If anyone uses their linear rails, whether it may be the N, T or W series, I would really appreciate some opinions. If you use their R system (which are advertised as drop-in replacements for the regular linear bearings like LM8UUs), I would also like to hear about how these handle and wear.

I have only had one sticky LM8UU and I simply oiled it with car engine oil (which I assume can handle high temperatures) and it has been fine since. They are tight when new but after a few hours running in they seem to get a lot better. They do eventually develop some play after years of continuous use but are cheap and easy to replace.

I got some Igus RJMP-01-08 bushings to try and they were oversized and had loads of play. I contacted a rep at Igus (who had previously contacted me) to ask why they where oversized and he never replied. I could slide a kapton shim between the bushing and the rod!

I have never understood how bushing can work in this application. They have to have some clearance to prevent binding, but then they have that much play. As they wear it gets worse. Ball bearings have pre-loading, so they don't seem to have any play until they wear out. They do have more friction though.

There is a lot to be said for the original Mendel bearing arrangement. It is preloaded by the tension in the plastic parts and can be tightened if it develops slack. The rotary ball bearings have less friction than linear because the balls are separated and don't have contra rotating faces rubbing against each other.

Edited 1 time(s). Last edit at 12/21/2012 04:54PM by nophead.

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[www.hydraraptor.blogspot.com]

Oh, I guess I know what the problem with the Igus bushing is: You have to slide it into a H7 tolerance bore so that it itself compresses to it's designed fit (E9 tolerance). It is a little bit counterintuitive that they did not put this information on the product page, but I think it is in the PDF catalog and - funnily - in the overview page for their R sytem. No wonder that I have seem quite a few people using them incorrectly in their RepRaps.

But honestly, I only looked this up because someone else told me about that. For direct replacements of LM8UU's, these should work better.

Yes I realised that but the odd thing is the outside was not oversized so I can't see how putting it in a hole with the same bore can shrink it about 0.2mm. Maybe I am missing something, which is why I contacted the rep.

They also state "The dimensions are identical with standard recirculating ball bearings. ", which is untrue, they a bigger than LM8UU.

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[www.hydraraptor.blogspot.com]

That truly is strange. There are two versions of this bushing: a standard one (RJM), for which they explicitly mention that the tolerance will only be met after inserting it into a bore and the more precise version RJMP, about which this piece of information is a little bit more vague. Furthermore, according to the datasheet, the outside diameter should be 16.2 mm for both versions.
How did you try to contact them? I could only send a mail via their site (or phone them) and when I clicked the send button, it jumped straight back to the main page in a fraction of the normal site loading speed without any sort of confirmation whether my action was succesful, so I am a little bit suspicious about that.
I read a lot of positive remarks about their customer support, so not replying to you seems out of place and strange...

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they are bigger than LM8UU

You mean like 1 mm thicker and longer each? Just looked that up. Not only the 100% plastic versions, but also the aluminium encapsuled version are a little bit bigger.

uGen Wrote:
-------------------------------------------------------
> That truly is strange. There are two versions of
> this bushing: a standard one (RJM), for which they
> explicitly mention that the tolerance will only be
> met after inserting it into a bore and the more
> precise version RJMP, about which this piece of
> information is a little bit more vague.
> Furthermore, according to the datasheet, the
> outside diameter should be 16.2 mm for both
> versions.

I just measured one again and it is 16.00mm

> How did you try to contact them?

I replied to an email from their UK FAE.

> You mean like 1 mm thicker and longer each?

Yes they are 1mm bigger all round. That means I can't just drop them in any of my machines to try them. I would have to build a new machine so I didn't pursue it.

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[www.hydraraptor.blogspot.com]

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I replied to an email from their UK FAE.

I see...

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Yes they are 1mm bigger all round. That means I can't just drop them in any of my machines to try them. I would have to build a new machine so I didn't pursue it.

That's crazy! I will inquire about that when I hear back from Igus. Maybe the contact person for students whom I mailed is already in her holidays or something.

Hello, firstly I am sorry that no one replied to your enquiry and that you are having issues with our website. We have a strict rule of replying within 1 hour to emails, so something has gone awry here.

All drylin R linear bearings will have greater clearance than the linear ball bearings. This is a requirement of all plain bearings, not just drylin. In fact, the drylin ribbed design allows a tighter clearance than simple plain bore plastic linear bearings.

To achieve a precision fit with the drylin N rail, choose the pre-tensioned carriage, NW-02-27-P.

To have a simple, low cost, adjustable linear system use the WS-10 rail fitted with WJUME-01-10 bearings.

I hope this helps, any problems please email me, maldridge@igus.co.uk (my email will only be checked every few days over Christmas).

Oh, didn't know that there was an Igus representative on this forum. Awesome!

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and that you are having issues with our website

Well, it looked strange to me that I got linked back to the main page without any confirmation, but I will wait for a reply until after the holidays. After all, the contact person for students whom I tried to mail might be in her holidays already. Maybe I am just a little bit oversensitive about such details...

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All drylin R linear bearings will have greater clearance than the linear ball bearings. This is a requirement of all plain bearings, not just drylin. In fact, the drylin ribbed design allows a tighter clearance than simple plain bore plastic linear bearings.

Yes, I understand this is due to the gliding nature of the plain bearings. However, what struck us as odd is that the outside dimenstions of the LM8UU equivalents that I looked up (RJM-01-08 and RJMP-01-08) are 16mm (diameter) and 25mm (length) as opposed to 15 and 24mm respectively.
EDIT: Just saw that there are also LME8UU bearings whose outside dimensions match with the RJM / RJMP series! Sorry about the confusion!
Also, that is quite an interesting fact to read about the ribs. I thought they might have been designed in to reduce friction and to allow dirt to pass through instead of accumulating in front of the bearing.

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To achieve a precision fit with the drylin N rail, choose the pre-tensioned carriage, NW-02-27-P. To have a simple, low cost, adjustable linear system use the WS-10 rail fitted with WJUME-01-10 bearings.

Can you please tell me how precise the drylin rails really are? According to the N series product page, Igus recommends the T and W series for applications where precision of < 50µ is necessary. What threw me off was that the service life calculator consistently claimed that I would have at least 0.1mm play no matter what system I chose and what parameters I entered, which obviously contradicts what the product pages claim.
Also, I am assuming that the adjustable version of the T series should have less play than the non-adjustable version, but again, the service life calculator says play is 0.2mm and 0.1mm respectively.

Unfortunately, the WJUME series is a little too bulky for my X and Z axes, so I am considering to use the new TWE-12 for those because I would like my whole system to be adjustable to account for wear.

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I hope this helps, any problems please email me, [email][email protected][/email] (my email will only be checked every few days over Christmas).

Thank you very much for your (prospective) customer service! I am located in Germany though, so I think it might make more sense to contact the local customer support.

Edited 2 time(s). Last edit at 12/23/2012 12:26PM by uGen.

A little update:
I contacted Igus Germany (took them some time to reply to my mail, but continuing the conversation over phone was a breeze; I barely pressed the connect button as the phone got picked up by the one who answered my mail. He was mighty helpful, too) and discussed the matter of the 0.1mm play as indicated by their online calculator. There are two samples on the way now. I will report back when I get the parts.

Finally got the samples. The customer service was very nice, helping me to locate the delivery after I wondered what took so long for it to arrive. Turns out it got delayed because there were parts missing at first.
Anyway, here are some pictures and my first impressions:


Group shot of everything I received. Initially, I was only interested in the W system (the beefier rails), but they were so kind to suggest and send me the T system sample for comparison, too.


Drylin TWE-04-12


Note to myself: be extra careful with these plastic adjustment screws! They get damaged easily


The glide pads of the little carriage


Drylin W10 from below. Adjustable WJUME-01-10 on the left and WJUM-01-10 on the right


The glidepad of the WJUME (which is easily exchangeable)


The adjustment system looks and feels much sturdier than that of the TWE



First impressions:

Both the W and the T system have points that I like and also points that I dislike.
Starting with the W system which I first considered using in a sturdy printer/mill, I really like the heft it has got to it. All the parts feel extremely solid and heavy duty which kind of reflects the intended purposes of this system. It is designed for more demanding applications than our light duty printers, so the additional inertia imparted by the massive cast zinc bearings will be difficult to deal with. This might be better suited for the Z axis, providing additional support to the whole structure (as it comes with a whooping 5.5mm base plate. However, if you - like me - want something sturdy with which you can also mill stuff, this might also be suited for the faster moving axes.
What I found especially remarkable is the little hex screw for setting preload on the WJUME bearing. It certainly has got a positive, machined feel about it that makes me think this will last a long while.
The downside of this system is its size. As you can see on the photos, both the rails and the bearings (you will need at least 3 of them) are quite the behemoths (although the double rail also comes as a 40mm version; my sample is the 80mm one). Retrofitting one of these or even designing a reasonable printer around one will be difficult.
The T system is kind of a mixed beast when it comes to quality. The carriage feels better made than the W bearings (but is also twice as expensive), with an overall better fit and finish. It also feels lighter, but right now, I don't have any scales at hand to quantify this feeling. One letdown was the adjustment system. Not that it doesn't work (actually, it works really well), but rather the plastic of the adjustment screws cannot compare to the nice metal ones of the W system. This is in part justified in that the shape is quite complex (with a single helix around the screw and some detents on its head) and would cost a lot to manufacture in metal, but I already damaged the sample a little bit by not being careful enough with it. Now that I have figured out a safe way to turn the adjustment screw, it is ok, but still, metal would have been nicer. Not that you have to fiddle too often with that, though.
The rail itself is both more flexible than the W system in that it is much more compact and also potentially more difficult to align as this design inherently does not offer any double rails. The height of the system is also favorable; 13mm vs 18mm can make parts just fit right in or not. This might be the better suited for standard RepRaps, where the M3 screws for affixing the rail and mounting things onto the carriage will suffice (the W system uses M6 screws). I have yet to calculate whether they will do the job for my light mill, too.
You have to use multiple carriages with this system, too, by the way.
Comparing the play, I think the T system wins here, albeit by a small margin. I guess having a whole plane to fit the adjustable glide pads against vs. a single point in the WJUME bearing makes the difference.
Update: Play is as good as eliminated when you assemble multiple W bearings into a carriage.

The vertical load carrying capability of both systems is about comparable, with one single W bearing being able to carry a little bit more (1200N vs 960N in Z axis) than the T bearing. However, the max. side load for the W system is higher (1200N vs 480N), but this only applies when you apply force from the bigger side of the W bearing. Else, it is 250N vs 480N (which is kind of moot because you would only use the W system as a double rail, anyway).

Since I am also developing my own DIY bearings, it may be of interest to compare both.
The Igus bearings have less friction (guess they put PTFE in there), generally running a bit smoother. Both the UHMWPE I use and the Igus material (Iglidur J in this case) are self-lubricating and hard-wearing. However, I still have to find out how long my bearings are going to last, but I am quite confident as the material is being used in knee prostheses. The advantage of the DIY bearings is that they cost like 1€ per piece or even less and that you can completely manufacture them yourself with basic tools, so you could equip your RepRap with a milling tool and start manufacturing them.
Generally, I expect the Igus bearings to outperform the DIY ones by far, but UHMWPE is dirt cheap and works quite reasonably, too.

Hope my research and findings may be of help for people investigating plastic bearings.

Edited 3 time(s). Last edit at 01/24/2013 11:08AM by uGen.

Very nice review
I'm really interested in a good working solution for the linear motion of a printer/mill...and igus seems to have great products!
So for this type of application the N series is not recommended? Also the 40mm one?
Thanks

P.S. The TWE-04-12 is the only one of the T miniature series with adjustable clearance?

Edited 1 time(s). Last edit at 02/03/2013 06:45AM by Pacca.

Pacca: Thank you!
Yeah, not only that; the Igus support is very nice, too. Give them a call, detail your project and they might send you some samples. I had it rather easy as a student, but I have read from others that you also get support as a private customer although their site says that they only sell to companies.
I don't know much about the N system other than that some printer builders have used them. Mauk's Cartesio and probably the MendelMax 2 (could not really confirm that from the pictures) are two examples. Igus states that their other systems are more precise, but their online calculator suggests similar results for all of their products.

Yes, it's is the only adjustable miniature carriage. Don't think they can go much smaller without compromising stability. And for size 15, they already have their standard adjustable series.

Thank you very much for your great informations
Did you try the T solution for a mill yet?
I'm a student too, and i'm searching the right linear rail for a printer/mill...so i will try give them a call (hoping for some samples )
I don't know which linear rail uses MendelMax 2, but the 1.5 used a Uni-guide from PBC Linear, i think...

You are welcome

No, I am currently in the process of evaluating the right linear guide for my printer/mill (hey cool, similar projects!). However, what I can already say about the TWE-04-12's glide pads is that they are quite annoying to exchange. The lower two and the one on the non-adjustable side are quite easy to pop out, but the adjustable pads left me puzzled. Even the Igus representative said they were a little bit finicky. The bigger and more expensive standard system seems a lot easier in this regard, judging from the product images on their website. Apparently, you have to unscrew the front plate and just slide the pads out. But I might be wrong, so don't take my word for it.
The T system's advantage over the W is that single bearings don't have as much play. Imagine the situation like clamping down on a shaft with a broad plane vs pinching it with a point contact. However, this might become moot as you need at least three bearings (like in the current designs) in order to constrain the X and Y carriages enough. In that case, even a point contact is enough and the lower price and superbly easy change of glide pads of the W double rail might be more desirable.
I have ordered a second sample of the W system, this time a 80mm wide double rail with a WJUME-01-10 equipped carriage to test the play in a more realistic setup than what I have done before (since I only had one WJUME and one WJUM, determining play was quite difficult).

That might have been carried over to the MM2, then. Some of Igus' and PBC's products look suspiciously alike. But the MM2 uses the W double rail on it's Y-axis, that I am quite sure of.
While I really like some of the designs and the longer service life of PBC's glide surfaces (3-30 times according to different sources (in one case affiliated with PBC)), I see some trouble coming with the fact that they are neither exchangeable nor adjustable. So after they wear out, you have to exchange the whole carriage.
Now this sounds quite extreme at first, but I have calculated that the Igus bearings will last me 3 years if I print one medium sized object every day (resulting in 15km running distance per X and Y axis). I tend to think that my calculations are a little bit off with a positive bias, so actual running distance might be quite a bit less.
With this in mind, the PBC bearings might outlast your printer. However, I calculated service life for optimized loads, placing heavy parts in a way that distributes forces applied to the bearings evenly (took me quite some time to find a good overall layout). If for some reason you cannot design your machine like that, service life rapidly dwindles, which is where the PBC bearings will show their problems.

Different parts of the world, same project, yes this is cool! (yesterday i found also this printer/mill but i don't like to buy diy machines in a kit because i also love to design, with all the details and the mechanical solutions that i want)
I think i will soon order some parts too, to make a couple of tests and see what linear guide is good for me...
Googling around (lol, wow, it is a verb) is also found some V-rails (MakerSlide and Open Rail but are a bit pricey for european customers...)

I saw the Power Wasp, too, but although they sound quite ambitious, they don't really have much besides 3D renderings in their shop, which strikes me as rather strange. One photograph I have seen of their X-Axis, though did leave me wondering why they did not opt for better solutions: They put drawer slides in there. Compared to cheap linear rails like the Igus W system, I don't think drawer slides stack up that well, especially since Accuride, a manufacturer of drawer slides and a linear rail based on drawer slide technology, puts a "10000" (which I assume refers to the rated actuations) in their product PDF.
Interestingly, they have put something like the N-series rail on their Y axis.

That's quite something. I also found both the MakerSlide as well as the Open Rail. While the MakerSlide was not that attractive to me due to its size and lower durability, the more flexible Open Rail sounded more like something. Did you calculate shipping to Europe for the Open Rail? (heh, calculated the shipping of 6 steppers from Sparkfun: >40$ to Europe! urgh. Luckily, I found an online store based in the UK.) The MakerSlide seems to be available from some European resellers, though. I think I found it in the shop of a Sparkfun partner.

The Power Wasp, except for the store made only of 3d renderings as you said, seemed to me like a solid printer/light mill...but I didn't saw that photo! And from the building video I didn't realize what linear guide was the one of the X axis

Why you say lower durability of MakerSlide?
Unfortunatly the Open Rail store does not have a shipping method to Italy (I can send an email asking if they can found a way, but I know that it would be too expensive). There is also MakerSlide Europe, with £30 of shipping to Italy

Yeah, it looks quite sturdy indeed and also showed that it is capable of milling. The only two things I would do differently in this design are:
building a solid connection between the two towers. They might be quite stable on their own, but constraining the whole construction is better. The Prusa Mendel design has shown how the printers can shake up when the Z axis is not stable enough and you print at just the right speeds.
And maybe make the y axis a little bit longer. It looks fairly short right now, but I could also be wrong about it...

Sorry, but I could not find the picture of the X axis again. I was pretty sure that it was either somewhere in their blog or on one of the 3D-printing news sites.

The MakerSlide is only anodized against corrosion IIRC, whereas the OpenBeam also comes as a (more expensive) hard anodized version that allows you to use metal V-Groove bearings on it in addition to the standard Delrin ones. There are some concerns by other people that the metal bearings will "push" away the anodized layer, though. So I don't know if the benefit of metal bearings is only on paper. Hard anodized rail surfaces should still be more durable than normal ones when used with the Delrin wheels.

Urgh. 30€ indeed is quite a lot. I tried to find the shop where I have seen the MakerSlide (only looked at the UK vendors this time, could also have been from another country), but to no avail so far. Maybe you have more luck: Sparkfun distributors of which one might carry MakerSlides.

You are right! This is why I don't like the printrbot variant (although having a lower Z axis should help reducing this problem). However the print area (I think that the mill area is more or less equal) of the Power Wasp is 260x200x210 mm, so about the same of most reprap printers.

What I like about MakerSlide is that it is a linear guide combined with a construction element, but Open Rail is more flexible, as you said, because you can attach it on your own mechanical structure. Also there is one advantage of metal V-Groove bearings over Delrin wheels,I think, that is the possibility to have more weight on the carriage (always if there is no peeling of the anodized layer...)

Oh, why didn't I think of taking a look at the specs I wonder how they fit the whole carriage onto these short rails, though. If the bearings are too close together, it would lead to stability problems or increased play, but for milling, you need a stable construction...hmmm

Just remembered: PBC also makes linear rails similar to the MakerSlide. They are called Integral-V. I have no idea what they cost, though.
Other manufacturers include:
Bishop-Wisecarver
Isel Germany and, confusingly, another subcompany of Isel, Isel GmbH
TEA Hamburg
Yes, the higher load capacity is advantageous, but I don't think that the relatively small loads from a small printer / mill will exceed the specifications of the Delrin wheels unless you plan to build something bigger. The commercial manufacturers I listed above use hardened steel surfaces which definitely will last longer. I calculated the service life of the TEA system using their datasheet to be about 22-23AU, which would be the distance from here to somewhere in between Uranus and Neptune (well, closer to Uranus, but still, that's a lot).

You searched so many sites to find the best solution, I see!
I think I will do the same, also trying different linear guides (included ball type and roller type, I don't know if you have already searched something about these), when I have some spare time
Of course the TEA system can do the job very well (so your printer will last more than 2 years ), but price is a limit for diy machines, or at least for mine

Yeah, I totally ended up in analysis paralysis for some months looking for the best and cheapest solution.

I looked at about every solution I could find, from plain bearings to linear rails like in heavy duty CNC mills. While the super-precise linear rails at first seem like the non plus ultra (also given that they are not too expensive when you really search for the lowest prices), this level of precision is just not needed for DIY printers/mills. The other components like timing belts are the limiting factors here. Also, aligning them properly is quite annoying.
If the TEA system is about as expensive as the other manufacturers, it really may be a little bit expensive, but I have not contacted them about their prices and could not find them otherwise anyway. They also have plastic bearings similar to the Igus T series, though. A professional CNC builder spoke positively about their bearings, so I guess they shouldn't be half bad (their adjustment system looks at least equal if not better than Igus').

In the end, I think plastic bearings are quite the nice solution for RepRap. About zero maintenance, no lubrication needed so you won't get yourself all greasy when tinkering and reasonably cheap.
You might also want to check out the DIY bearing research thread if you want the absolutely cheapest solution compatible with many standard components. I wouldn't use the wimpy 8mm rails, though...

... I was testing with Igus-Drylin too some years ago but found them not sufficient for my needs (CNC-engraving) ... especially the lateral play increasing with time was the problem, in spite of the adjusting abilities.

Reassembled some linear bushing- and ball bearing-typed linear guides for simple XY-stages and found the ball bearing type (top-right) too insufficient if you need some long time stability: [forums.reprap.org]

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

VDX: thank you for the insight. Can you please tell us which bearings you used and what kind of CNC-engraving you do (as I could imagine wood not needing 10µ precision)?

The top right linear guide looks like an Isel one...I thought this design was supposed to be good in harsh environments (at least Bishop-Wisecarver advertised it to be)? What exactly is the limiting factor here?

Also, what kind of demands do you have? Of course, for a person who works on precision mills, RepRap looks like the most unprecise cartesian machine ever constructed
Don't get me wrong, I just want to see things in relation.

I have just read these posts for the first time and it is most informative. i would like to build a machine capable of metal milling using belts and bushes, so any progress in this department is helpful.

Nophead suggested that the original mendel roller bearing setup was nice as it can be adjusted. The downside that I can see is that the bearings are point loaded. Perhaps they could be improved by using square bar and hexagon bar for the two and three bearing setups. This would give a flatter surface for each bearing and might improve the loading. hexagon and square bar is available in stainless and the tolerances on bright drawn bar should be good enough for a linear rail. By careful design of the carriage it may be possible to support it midpoint on some of the axes.

There was a comment about why a bush pushed into a similar sized hole can shrink. A size for size fit is classed as an interference fit as the hole and bush are not perfectly round. Ovality and Tri lobing is common (Like the rotor in a wankel engine). The bush when pressed fully home will shrink slightly and this is accounted for in the bush manufacture.

Hi uGen,

yes, the right stage is from Isel - I've bought this then to build a manual SMD-placer like the mechanics in the Fineplacer here (bigger black-blue part on the left):

It has some 'play' in the used ball bearings in axial direction - with better (more expensive) bearings or with predefined tension this could be reduced to zero though.

With this sort of stages and others in different sizes ( ) I was then developing all sorts of microassembly systems or related stuff (optics, 3D-microvision, grippers, ...)

The highest precisions were 1 micron mechanically with high accurate linear drives - here one from Star with a motor+driver capable of 1000 fullsteps per rev. or x10 microstepping, positioning 0.5 microns per step:

... or nanometers to sub-nanometers precision with piezo-drives - have some with 25mm travelling range and up to 10mm/s speed

Edited 1 time(s). Last edit at 02/05/2013 03:06PM by VDX.

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

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uGen
While the super-precise linear rails at first seem like the non plus ultra, this level of precision is just not needed for DIY printers/mills. The other components like timing belts are the limiting factors here.

In fact the new Aluminatus uses only leadscrew and no belts...

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uGen
In the end, I think plastic bearings are quite the nice solution for RepRap. About zero maintenance, no lubrication needed so you won't get yourself all greasy when tinkering and reasonably cheap.

This is the reason why I was mainly oriented towards plastic linear guides: zero maintenance!

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uGen
You might also want to check out the DIY bearing research thread if you want the absolutely cheapest solution compatible with many standard components.

I'm searching not the cheapest solution, but the right compromise between price and quality (with this primarily in mind)

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VDX
With this sort of stages and others in different sizes ( Linearachsen-Alle.jpg ) I was then developing all sorts of microassembly systems or related stuff (optics, 3D-microvision, grippers, ...)

I can only say that I want this big assortment of linear guide just to put them on a shelf in the living room

> I can only say that I want this big assortment of
> linear guide just to put them on a shelf in the
> living room

... my living room isn't big enough to hold the shelfs for all of the interesting parts, so they are stored in the basement

And the linear guides aren't so interesting anyhow ... luckily enough the much more intersting parts are mostly micro- and nanotech -- so fit together in some small and medium sized cases and boxes

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

@martinprice2004,

The RJMP bushings I have are fractionally less than 16mm all round so I can't see them shrinking in a precision 16mm hole. The website says they should be 16.2 but they aren't and I got no reply when I asked the rep why. I can squeeze them so they are tight on a rod but that would require a hole about 0.2mm undersized.

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