Today, we're going to be talking about linear rails on the Ender 3 Pro.
Linear rails, the big question, do they improve performance? Well, the answer is yes and no at
the same time, and here's why. Linear rails are not about making your prints look better,
but it's definitely about keeping the consistency of your prints the same throughout the life of
the printer's use. In other words, once you have your rails set up perfectly,
there's nothing left to adjust. At that point, you're really just doing some basic maintenance.
For instance, the MGN12 carriages on these MGNH rails are metal on metal. There's ball bearings
inside of these carriages. Metal on metal contact requires that you have some sort of lubrication to
ensure that you do not accidentally prematurely wear things out. That's where things like super
lube comes in. You take a very tiny amount and you just smear it where the grooves are, and that's
where the ball bearings inside the carriages are going to move. That's pretty much it.
You just clean it off and put a new application of lube once in a while and you're pretty good.
Here's the thing, linear rails putting them on, getting them perfect,
is a nightmare [chuckles]. It's not for the faint of heart. It's not a beginner mod, it's not even
an intermediate mod. For the setup that I've got specifically, you must be intimately familiar with
everything involving your printer's frame because if you're not, you are never going to get it on.
Let's talk about the components. The Z-axis and the X-axis, I got from AliExpress
from a company called Funssor. I'm probably pronouncing that wrong,
but there will be a link in the description about it. The Z-axis is the one that's a nightmare, and
the reason why it's a nightmare is if you try and do it alone, I guarantee somewhere in the process,
you're going to have the carriage slide off of the rail and you will lose ball bearings
and have to replace ball bearings. That happened to me when applying this mod for the first time.
That being said, there is a very cheap way to avoid that. This is a little plug that's designed
to go inside of the little holes where you would put in screws for the rail. Definitely get some
of these. This will make your life easier because this little stopper prevents the rail from sliding
off when installing your frame. Free tip. Big tip. The next question is, do I have to bother with
genuine Hiwin rails or can I get the cheap ones on Amazon or eBay, etc? The answer is,
absolutely you do not need Hiwin rails, in fact, I think Hiwin rails are probably completely overkill
for a 3D printer. How do I know that? I've got an identical printer to my right and this is all
just Chinese knockoff rails that we got on Amazon for half the price
of the genuine Hiwin stuff. It works perfectly fine. They're honestly just as good in terms of
constrained motion. There is no need to go with Hiwin. I went with Hiwin on this build because I
wanted to make that comparison, and in a future video, I will make a genuine comparison between
genuine Hiwin and what's often referred to as Chiwin because it's a Chinese Hiwin knockoff.
Getting on from there, let's talk about why everything is a nightmare to set up at first.
Now, it has to do with binding. These carriages are on the rails in such a way that the motion
is almost absolutely truly linear. There is no wiggle room. If this rail is
tilted like a quarter of a degree from this point to the top, that will make the top go over to the
right or the left off by just a few fractions of a millimeter. Because that is dependent on this one
also being level, as you go up, you will have this side start to bind, and then you'll get
stuck. If these are not perfectly level with your frame, you're going to have a problem.
The same thing goes for the Y-axis system. This is not from Funssor, this is actually from
PrinterMods. I went with the one from PrinterMods specifically because it utilizes the stock Y-axis
carriage but it's also a dual rail system. There are ones out there that are a single rail system
and then it's got a modified Y-axis plate right here that connects flat but I didn't want that
because that could introduce the possibility of a wobble if you're starting to go really fast and it
just seemed like a better set up to go with dual Y-axis. Again, if the Y-axis carriages are not
perfectly level with each other, they will bind. In my case, I had some really annoying problems
with the Y-axis. First off, it's the same concept. If this bolt right here has the rail lower than
all the way in the back, now you've got a wiggle. You've got one rail going up or down slightly.
If the other one doesn't mirror that perfectly, then as you move back to the part where it's not
completely mirrored, you're going to bind up, and then you're going to get stuck.
Another thing I had to deal with is these were not perfectly aligned with the stock Y-axis plate. I
actually had to shim the distance between the MGM12 carriage and that metal plate right there
that has adapted onto the Y-axis gantry. That was a little bit of a difficult process,
and it took a few days to figure out what was going on. Basically, those bolts
are not-- I'm trying to get my camera to focus here. They are not perfectly straight up and down,
so if they were to bolt down and they were perfectly straight up and down,
they'd be perfect, but they weren't they were actually tilted in like this. Instead of going
straight down, it had to go in a curve because this rail is poking out a little too much.
I just used some washers, shimmed it out, and now it runs fine. It doesn't bind anymore.
There's a certain process to getting everything completely mirrored, and it's a long process.
The same thing goes for the Z-axis. The X-axis is very easy because this rail just bolts in to
the extrusion here with just four bolts and then you're good. Then you got your carriage, you got
bolts on, or you got your-- I'm sorry, you got your plate that bolts onto the carriage here.
This is not the stock plate, this is no longer the exact same thing as what you would have on
your stock Ender-3. You're going to have to find a design for something that holds
your fan and your ABL mount with this system. I personally designed this system. I call it,
My Companion mount system. You could find it on my Thingiverse page. If you have this particular
X-axis system and you just want to run the stock fan and an easy ABL, just print it in ABS,
and you're good to go. Perfectly easy to do. It's free. It's for you if you need it.
Then let's talk about quality and consistency then. What's the point of going through all
this if it's so difficult? Well, the reason you would do this is for the consistency.
You're not really going to see better prints because of this but what you're going to find
is that every single print will come out just as good as the last based on your slicing settings.
What you're doing is you're removing a variable. That's what this is all about,
removing variables during the diagnostic process. When you know that there's a certain component
that is the exact same every single time, that's one less thing you have to consider when you're
diagnosing a problem with a print. Linear rails are very, very consistent, and once everything is
lined up and tightened down, you probably don't have to ever adjust them again,
not for a very long time. This is not a CNC system, nothing is really under
a lot of load, so the chances of anything really coming undone is pretty slim especially if you
use little crush washers on all your connections, that's really going to hold everything in place
by using a little bit of pressure on those threads to keep everything nice and tight.
When you're running a production machine, the consistency is very important
because when you're trying to figure out what happened here, or why is this not printing right,
having one less thing to consider is a huge deal because time is money, and the more time you spend
trying to diagnose a problem, that's less time you're printing. Less time you are printing means
less things you are making money off of. That's the reason you would invest in this system.
If you are just doing some general printing at home,
this is really not necessary. This is the kind of set up for the person that's printing 18, 19,
20 hours a day every single day like I am. That's the whole thing, that's why you would do this.
Linear rails, are they necessary? Absolutely not. Are they a genuine
improvement to the overall experience of printing in the long term? Absolutely,
but you have to make that decision yourself for if it's worth it. It's also very expensive if you go
with genuine Hiwin rails. Again, I don't think that's even necessary the Chiwin stuff works
perfectly fine. Save yourself a buck or two if you're going to do this whole system.
I'll put a link in the description to where I got everything and if you want to take it on,
more power to you but I think this whole setup is perfect because it utilizes the stock
frames. The 4040, the 2020, the 2040, they all work with stock frame components which
means modification is very easy. Things like my belt tensioner works. This is a nice metal,
belt tensioner. This is another metal belt tensioner. My light up here attaches properly.
Once you go some with something like Fuse 3D and their proprietary systems, you lose the ability
to start using things that are already available on the market for your system.
That's why I chose this, that's why I did it. I hope that it helps guys. If you want to see more
content like this, just subscribe and check out my videos once in a while. Thanks for watching.