I really like my Sintron printer – but there’s a few things I’d like to improve:

  1. The Sintron wobbles quite a bit and I’d like a more rigid printer – this should allow me to print faster, and with fewer unwanted ripple artefacts on the Z-axis.
  2. The Sintron only allows me to extrude one filament at a time – I’d like a design that allows for dual extruders.
  3. The Sintron allows about a bed size with a maximum of about 200mm x 200mm (maybe a little bit more, but not much). I’d like to have a printer that’s big enough to allow me to upgrade the bed to a bigger size.

I’d also like the challenge of building a printer from scratch.

A printer that I’ve had my eye on for a while is the Taz 5 from Lulzbot. This is a pretty awesome looking printer and ticks all three of the boxes above. It’s commercially available, but the plans and any 3d printed parts are also open source. I’d like to see how feasible it is to order the individual parts and build this printer myself.

The other thing that I haven’t done previously is work with the open source Marlin 3d printer software – though I’d not expect to make any changes to this software beyond configuration.

I’m going to create a series of blog posts documenting the steps I take to build this printer, and you’ll be able to see my progress as I go along. I’ll use my Sintron to print all the necessary parts.

The last thing I’d say is that this is kind of a voyage of discovery for me too. I’m sure I’m going to make some/lots of mistakes along the way – I’ll try to document them so anyone following this guide doesn’t do the same.

Part 1 – Y-axis, front end assembly

You’ll need:

  • 2 of M5 knurled insert nut;
  • 2 of M3 knurled insert nut;
  • 4 of M3 x 25mm bolts;
  • 4 of M3 washers;
  • 4 of M3 nylon lock nuts;
  • 2 of M5 x 25mm bolts;
  • 2 of M5 washers;
  • 2 of 609 ball bearings;
  • 1 of M8 x 35mm bolt;
  • 2 of M8 washers;
  • 1 of M8 nylon lock nut;

The finished assembly for this part will look like this:

fully assembled front view

1. Download the STL files for the left and right assembly uprights, and print one copy of each – the links for these are below:

The STL for the Y-axis left corner mount is here.

The STL for the Y-axis right corner mount is here.

Y-axis left and right mounts

2. Now insert the M3 knurled insert nuts into the holes on top of these two parts. I did this using a soldering iron. I heated it to 400C, and placed the nut up on the hot tip of the iron. Then I carefully pushed the nut into the hole on top of each of the mounts printed earlier.

Y-axis left and right mounts - top view with nuts

3. Insert the M5 knurled insert nuts into the upper holes on the side of the mounts, using the same technique as described above.

Y-axis left and right mounts - back view with nuts

4. We’re now going to construct the bearing mount for the Y-axis. Print the bearing mount (you can download the STL from here).

Y-axis bearing mount

 

 

 

 

 

 

You can see with all of these printed parts that the edges which touched the printer bed are still quite rough from the brim (which I’ve removed). I have to sand each of these edges, and then rub some acetone around the sanded edges to smooth them off.

5. Next you’ll need to fix the 609 style ball bearings and washers into position using the M8 nut and bolt. The photo below shows how these are ordered.

Y-axis bearing mount - exploded view with bearing

Note that the washers go immediately beside the ball bearings, rather than on the outside of the plastic mount. The photo below shows this unit fully assembled, also with 4 M3 nyloc nuts inserted into the hexagonal mounts.

bearing mount

6. The front panel is not 3d printed in the factory Taz 5. Fortunately, a Lulzbot community member posted STL files for the front end with the bearing mount holes, and also for the back end with the motor mount holes. These aren’t symmetrical, so beward of this when printing them!

They are big parts – I had to lay them out diagonally on my Sintron’s heated bed, as shown in the screenshot from Cura below.Cura - y-axis front

I printed 3 of the front ends, and used an ABS/Acetone mix to weld the plastic parts together, as shown below. Again, this is still a bit rough around the edges, as I hadn’t sanded down the artefacts left over after peeling off the brim.

unsanded front panel

The photo below shows the part after cleaning it up with some sandpaper, and finishing with some 600 grit paper.

sanded front panel

Finally, I used a rag dipped in acetone to smooth out the edges further, as shown below.

acetone smoothed front panel

With hindsight, I think that printing only a couple of these pieces would have been necessary, rather than 3 pieces.

7. This is the final step, where all the parts are attached. First we attach the bearing mount using 4 M3 x  25mm bolts, which attach into the nyloc nuts in the bearing mount. Secondly, we attach the two left and right corner mounts using the M5 x 25mm bolts. The photo below shows the assembled front bearing mount.

fully assembled front view

The rear view of this part is shown below.

fully assembled rear view

Next time I’ll look at building the corresponding rear motor mount assembly.