3D Printer Build

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

bmac2

Well-Known Member
Project of the Month Winner
Joined
Aug 16, 2013
Messages
1,033
Reaction score
764
So I decided to start a build thread on this thing and perhaps share my pain. I needed a new project and started work on it just after Christmas. I’d been reading a lot on the internet, and watching a lot of videos on 3D printing but after watching Thomas Sanladerer series “Dolly: The Prusa i3 MK2 clone”. I had to admit I‘d been bitten, I’m still not sure that I have a practical use for one and I certainly don’t think I need one but now I wanted one and I wanted to build it. Tom built Dolly using cable ties and Oriented Strand Board. I thought I should be able to do at least as well just by using something like Baltic Birch plywood. I know it could work out cheaper to just buy a kit but where’s the fun in that? I don’t buy ready-made engines.

I’ve been concentrating on posts where people had either built their own or mods to improve printers and basically stealing everything I thought looked like a good idea.

One recurring problems was rigidity so I’m going with all metal. No wood and sorry Tom cable ties are for tying cable and putting up my wife’s pea fences in the garden. I have a couple of concerns about the potential weight of the X axis but I’m willing to sacrifice print speed for rigidity. As my ideas slowly solidified I started ordering the parts and after Christmas had enough to start getting things tougher.

I used 2020 and 2040 V-slot channel for the basic frame. I had some V-slot and linear bearings left over from my laser engraver. That project could have done with some better planning.

With the corner brackets and T nuts I knew I could have a solid, square frame in no time. After bolting up the frame I marked out and drilled the end plates for the X axis and mounted the Z bearings. I was going to just center punch for the holes (Thoughts of Thomas Sanladerer’s oriented strand board and a hand drill) but chickened out and spot drilled them using the DROs on the mill with the two plates sandwiched tougher then drilled out the 3 and 4mm holes on the drill press.

0012 X Axis Left Plate IMG_2740.JPG

X carriage IMG_2753.JPG


I’d left the extrusions at their stock length (400 and 500mm) my plan at this point was just have a platform I could build on and cut them down to size later.

0020Frame IMG_2751.JPG
 
Last edited:
The bottom mount for the Z guide rods does double duty as a 90 degree bracket for the 2040.

1030 Z Rod Mounts 001.jpg

I squared up two pieces of 1 in. thick bar stock and trimmed them to 40 x 40mm. I don’t have a lot of metric tooling but between fraction, number and letter drills I can get pretty close and for this project I did order 3, 5, 6 and 8mm reamers for when it has to be right.

1040 Z Rod Mounts IMG_2794.JPG


1060 Z Rod Mounts IMG_2796.JPG


I then milled the step and drilled and counter sunk the holes for the 5mm button head screws.
1070 Z Rod Mounts IMG_2819.JPG
 
I have a couple of 8mm lead screws I was going to use on my engraver (bad idea . . . don’t ask) and made the drive nut holders out of .375 aluminum. The only material I had at hand is this stuff that for whatever reason has a rounded edge but it worked.

Cut off two pieces and cleaned them up bringing them down to size then drilled them to fit the drive nut.

Drive Nuts IMG_2941.JPG


Drive Nuts IMG_2943.JPG


Drive Nuts IMG_2799.JPG


They could almost be used as is but I wanted to round them off and trim them up a bit. After all if I don’t throw in a bit of style this thing is going to look very industrial.

Super lazy setup for the 3”rotary table just toss it in the vise. I used my Arduino controller and once I got the angle dialed in it was just “A” forward, “B” reverse, “Z” down and repeat.

Drive Nuts IMG_2944.JPG


Drive Nuts IMG_2945.JPG


Drive Nuts IMG_2947.JPG


Drive Nuts IMG_2948.JPG


After finishing them I found I still had to take a small bite out of the end to clear the bearings

Drive Nuts IMG_2949.JPG


And this is why if you build an Arduino Controled Ratary Table you put it into a tight case.

Drive Nuts IMG_2946.JPG
 

Attachments

  • Drive Nuts IMG_2944.JPG
    Drive Nuts IMG_2944.JPG
    93.4 KB · Views: 363
It was at this point I saw a Myfordboy video on his printer build where he isn’t using flexible couplers (around the 7 minute mark). I guess if you build it straight you don’t need them, so another idea got pinched.


 
The more I looked at the frame the more I dreaded the idea of cutting it down. I had some 5mm threaded rod that’s long enough and straight so I thought I’d give the Myfordboy idea a try.

Started with some .375 aluminum and drilled and reamed it 5mm and parted them off.

IMG_2893.JPG


After dialing in the rod I used the tale stock to slide the coupler on with some JB Weld and left it overnight to set.

IMG_2894.JPG


I took a skim cut just to clean them up then marked them for the setscrews.

IMG_2898.JPG


I decided to drill and tap the hole thru so that if I want I can use two setscrews.

IMG_2904.JPG

IMG_2905.JPG

IMG_2906.JPG


I cut a couple of lengths of aluminum angle for the top guides for the Z axis and after indicating in the mill drilled and reamed the holes for the 8mm rods and a small bearing for the screw.

IMG_2912.JPG


IMG_2913.JPG


IMG_2914.JPG


That about brings this thing up to date. Next up I’m starting on the X axis.
 
This project must be for the fun of making the printer. You are definitely going to spend more money on making one than buying one.
 
I own a Preusa Mk3. Your printer will be a lot more accurate and rigid than it is. That should give better print quality and the ability to run faster. It will take a lot of experimenting to achieve that, though. Good luck.

Lohring Miller
 
One thing to remember with 3D printers is to keep anything that moves at speed ( print bed and extruder ) as light as possible as inertia can cause a real problem , usually shows up as “artefacts” on the printed part .
 
Vederstein

A lot of what I’m using is stuff I already have on hand, Adriano’s, stepper motors/drivers, misc. aluminum. Nothing goes into the garbage (printers?) around here, and maybe the odd time at work without getting stripped of anything I find interesting. The Anet 8 goes for around $250.00 Canadian with shipping and from everything I’ve read can be a very good printer so long as you don’t try to push it past its limits. But like most of the low cost / affordable to the hobbyist / printers it uses a lot of acrylic and can suffer from issues with flexibility and vibration if you try to push it.

Looking at my spreadsheet on this thing I’m around the $150.00 mark so far. Now I have no illusions that I won’t want to upgrade some of these parts in the future, they are mostly the cheapest I could find but I’ll deal with that as I have to.

Amazon

LETOUR Power Supply 12V Power Supply 30A 360W $31.99

50pc 20 Series European Aluminum M5 T Nut $4.03

Smart LCD Screen 2004 Display Controller for RAMPS 1.4 3D $12.76

SODIAL(R) 3D Printer Controller for RAMPS 1.4 Reprap $6.57

Hotend All Metal V6 Extruder $8.86

Banggood

4) - LM8LUU 8mm Long Linear Bearing $ 8.16

2) - Nema 17 42mm 12V Hybrid $29.08

12/24V MK2B Heated Bed Platform for 3D Printer $15.70

Left/Right Side Aluminum MK10 Direct Extruder $10.95

Alliexpress

2) - 400mm Length 2020 T-Slot Aluminum Profile, 1) - 2040 T-Slot $15.76

power switch $2.24

TOTAL $146.10

Before anyone asks YES I have checked RAMPS board and the foil pattern and MOSFETs are fine.

Lohring

“Will take a lot of experimenting”

That’s why I opted for a RAMPS board running Marlin. With the amount of information available on the internet I think I have a much better chance of getting it up and running with this platform. I did try to contact “Technical Support” on this build for some reason they have my phone number and e-mail address for the help line. I guess I’m on my own . . . except for you guys.

XD351

Yep it should be ridged enough but like I mentioned before I do have some concerns with the weight of the X axis that’s one of the reasons I’m going with a Bowden style extruder.

As I start getting the materials piled up on the bench to start working on the X axis I can see that it’s going to have some weight to it. That said though I think with a ridged frame if I can get everything lined up straight and balanced it should (?) be able to perform as well as many of the commercially available kits on the market.

If nothing else if I can get it running and it craps the bed at some point I will be able to fix it.
 
Last edited:
With 3D printers of the usual sizes the part is light compared to the extruder assembly. My favorite design so far moves the extruder assembly in the X and Y direction and the part in the Z direction. Z moves are small and infrequent so all the rigidity needs to stiffen the X and Y axes. Ball screws rather than belts can help with accuracy as well. See https://www.projectr3d.com/#overview for a design like I described. E3D is working on a tool changing, multiple extruder design that's similar. By the way, Bowden extruders can have issues with flexible filaments. I have had some initial problems even with a direct drive extruder before updating the Prusa extruder assembly.

Lohring Miller
 
I think the reason most printers are designed the way they are ( bed does the y axis and extruder moves in the x & z axis ) is that it makes them easier to design and manufacture . This also seems to follow suit for cheap cnc engravers etc but if you look at a cnc mill the head only moves in the z axis and everything else is done by the bed . This keeps everything that moves at any sort of speed down low where vibration , any flexing and inertia can be controlled . I like ball screws and you can also add encoders to them to monitor missed steps etc and they don’t break halfway through a print ! Anyone ever seen a machine that can be switched from 3D printing to small cnc engraver to a small laser cutter all rolled onto one unit ? Might be a future project !
 
Not much progress on the printer. The weather has been just ugly with lots of snow and daytime highs on the wrong side of -30c the past couple of days.

I did get the Z motor mounts finished. I’m using aluminum angle for the mount and milling off the shaded areas in blue.

Z  Motor Mount 001.jpg


The only angle I have is 1 ½” (38.1 mm) and a NEMA 17 is 42.3 mm so I had to add a bit to get the width I wanted. I cut a couple of strips from the same material and then brazed them on to one leg.

Z  Motor Mount IMG_2918.JPG


Z  Motor Mount IMG_2920.JPG


They got a little ugly on the inside and warped a bit but a light pass on the mill cleaned them up nicely and brought everything back to square.

Z  Motor Mount IMG_2921.JPG


Then just drilled / bored them to fit the steppers and milled them to shape.

Z  Motor Mount IMG_2922.JPG
 
So this is the plan. Belt tension will be set with the two screws on the right. I started by cutting and truing up 5 pieces of .75 x .5” aluminum bar stock.

X Axis_Cad.JPG

0011 X Axis IMG_2924.JPG


Indicated and spot drilled them in the mill for the 3mm holes that will be used to attach them to the end plates then drilled and taped them in the drill press. I love my tap arm.

0011 X Axis IMG_2928.JPG


0011 X Axis IMG_2926.JPG


0011 X Axis IMG_2927.JPG


Then back to the mill to drill and ream the 8mm holes for the rods using the DRO.

0011 X Axis IMG_2929.JPG
 
With that done I spot the holes for the X carriage and finished it up on the drill press.

0011 X Axis Carrage IMG_2754.JPG


To assembly the X axis I started by screwing the five 8mm rod holders (I’m honestly not sure what to call them) to the end plates then loosely attached the bearings to the X carriage.

0011 X Axis IMG_2930.JPG


Then slid on the right and left plates. Amazingly everything lined up. Most of the shop time today was spent tuning the bearings. The only way to get the carriage to slide smoothly was to slowly tighten each of 12 screws one at a time. When I made my engraver I was surprised how much tightening just one of the screws just a touch would make.

0011 X Axis IMG_2931.JPG


0011 X Axis IMG_2932.JPG


Dropped it down over the Z rods to get things spaced out and as an assembly I definitely has some weight to it in the Z direction but the X isn’t bad at all.

0011 X Axis IMG_2933.JPG


0011 X Axis IMG_2934.JPG

0011 X Axis IMG_2935.JPG


By shining a light up from below and using a set of feeler gauges it looks good on the left but I’m going to need a 10 thou shim on the right side.

Drive Nuts IMG_2951.JPG
Drive Nuts IMG_2952.JPG


The more I look at it the less I like the belt tensioner. Using two screws to jack the idler out against the rods just doesn’t look/feel right . . . . might have to come up with a plan “B”.
Stripped it down so I could mill down the left end plate to match the stepper and clean up all the dirt, ink and scratches and it was time for a family photo before final assembly.

0011 X Axis IMG_2957.JPG
 
On my Anet A8, if you try and put a proper amount of tension on the X axis belt, the guide rods and ball screws flex and just don't allow it (both 8mm which I think you're also using). I'm not aware of a fix for this so I'll be eagerly watching what you come up with!

Also, just an FYI, the IGUS DRYLIN bearings are supposed to be a huge improvement over the LM8's, both in performance and noise. They're reasonably cheap and a drop-in replacement but I haven't gotten around to ordering a set yet.
 
Hi Al thanks for checking in. How are you holding up down under? From what I see on the news it’s either 40c or raining at biblical proportions. Any time your weather makes my news 15,000km away it can’t be too good.

Belt tension looks like one of those things that are all over the map. Some say it should sound like a base guitar string yet I recently read in a Thingomatic manual “If the belt makes an audible noise when you 'pluck' it with your fingers, it is too tight”. Might just have to go with trial and error.

Also, just an FYI, the IGUS DRYLIN bearings are supposed to be a huge improvement over the LM8's, both in performance and noise. They're reasonably cheap and a drop-in replacement but I haven't gotten around to ordering a set yet.

Everything I’ve read on DRYLIN bearings say that they can make an amazing difference over the ball races. One caution I’d offer before ordering any is to check the reviews. From what I’ve read many of the ones being offered on line are 16mm OD.
 
Hi Bmac, where I am is about the only part of the country experiencing mild, pleasant weather. This summer we've had a few 40+ degree C days but not as many as normal, and mostly we're seeing mid 30's which is very pleasant compared to most years. The weird weather systems going on are actually holding off the extremes we normally see - I'm definitely not complaining.

I can only offer my own anecdotal belt tension experience, I haven't got it guitar string tight, but when I added a tensioner to the Y axis and adjusted it quite tight I got much better consistency in that direction. When I tried the same tension in the X the rods just flexed and caused issues.

I just had a thought (dangerous, I know). At least on my A8, if the ball screws were outboard of the guide rods instead of inboard, I could run another rod horizontally perfectly inline between the upright rods, with another set of bearings of course, as a form of bracing to prevent them coming together. Too much work for me though and my prints are reasonable enough for what I need.
 
I decided to work on something simple while I ponder how to handle the X axis belt tensioner. The mount for the hot end is very reminiscent of a small split bearing so easy peasy. Squared up a piece of .25 bar stock to 1” by 1” and step drilled to 15/32” then reamed it 12mm.

Head Mount IMG_3074.JPG

Head Mount IMG_3075.JPG


Drilled two through holes #40 (0.0980 close enough to 2.5mm) then split it along the centre line. All it needs is an oil hole and it would be right at home on this forum.

Head Mount IMG_3076.JPG


Head Mount IMG_3077.JPG

I ran into a bit of a snag at this point. The idea was to tap the bottom part through as I’m using 3mm screws to mount the block to the carriage as well as the clamp and my tap wasn’t long enough. It was only about 1 – 1.5mm that the tap couldn’t reach so I cut a small notch in the end of a stainless steel 3mm screw and ran it in. It actually worked pretty good and the clamp feels very secure.

Head Mount IMG_3078.JPG


Head Mount IMG_3081.JPG
 
I started on the Y axis motor mount/belt tensioner. Now that it's done I think I might have “over engineered” it a bit but I like it and it is solid.

Y  Motor Mount IMG_3022.jpg


I started by cutting all the pieces to size and cleaning all the edges. The base consists of the bottom, two .125” spacers, .125” top and a .25” x .25” piece across the back. These where sandwiched up and clamped together then drilled and tapped for 3mm button head screws. Screwed up it forms a “T” slot for the motor mount to slide in.

Y  Motor Mount IMG_3024.JPG


Surprisingly my aluminum angle is still too short for the NEMA 17 so again I just extended it. The wind-chill was barking around -40c so instead of going out to the garage and brazing it I thought I’d just use JB Weld and a couple of stainless pins. If it doesn’t survive machining I’ll just bite the cold and braze one up.

Y  Motor Mount IMG_3023.JPG
 
Left it to cure overnight and this morning I realized that the rounded inside corner wouldn’t allow the stepper to fit flush with the inside of the angle. I set it up in the mill and just kissed it to bring it to square. This also trued up the bit I’d added to the top and the JB Weld held so I guess it will work.
Y  Motor Mount IMG_3026.JPG


Y  Motor Mount IMG_3025.JPG


Indicated it in the mill and then drilled and countersunk the screw holes and bored it out for the stepper.

Y  Motor Mount IMG_3029.JPG


Y  Motor Mount IMG_3030.JPG


Y  Motor Mount IMG_3031.JPG


Once I had it trimmed up I dialed it in on the mill with the sliding plate clamped down. I didn’t want this to move out of alignment so I drilled, countersunk and tapped the four holes without changing the setup.

Y  Motor Mount IMG_3033.JPG


This was the tricky bit. I slid the motor mount into the “T” slot in the base assuring it was tight against the back and clamped it down. Then carefully marked it so the drill would hit the center between the motor mount and the slide plate.

Y  Motor Mount IMG_3034.JPG


Opened up the hole in the base to clearance size and tapped the motor mount. The stepper wouldn’t clear the button head screws so I had to counter sink the top on one side.
Y  Motor Mount IMG_3038.JPG


The screw gives me a whisker over 3/8” travel and the 5mm button head in the front of the mount locks it into place. Over all I pretty happy with the way it turned out . . . . to bad it will be hidden in the back.
Y  Motor Mount IMG_3039.JPG

Y  Motor Mount IMG_3040.JPG
 

Latest posts

Back
Top