Tag Archives: video

Praxis

This weekend, I’ve just been having fun printing out things.

First up, I printed out a few of these snowflakes. This piece gave me a lot of grief during the week, trying to figure out the right settings to print it. It’s a real testing piece. Lots of sharp corners will test the limits of your printbed for adhesion on the first layer, and it’s an absolute nightmare for retraction. If your retraction isn’t perfect, it turns ugly, extremely quickly.

At one time during the week, I had my retraction spot-on. However, I hit the perimeter-speed bug in SFact, which prints out the perimeter of the first layer at 60mm/s. That was way too quick for this complex piece, so I had to upgrade SFact, which then means all the retraction settings were obsolete, and I had to start back from scratch. I got them sorted out on Saturday morning, and I’ve been having fun just printing ever since.

I’ll be printing out four of these snowflakes. My daughters are going to decorate them, and them give them to their grandmothers. Should be a nice Christmas present from them. Here’s a video of the snowflake in print. Have a look at all the retractions / relocations during this one layer!

Next up I printed up a screwable jewellery box. I thought that this would be an excellent piece to demonstrate just how well the printer is working now.

The box turned out beautifully, and screws together perfectly.

Just for comparison, here’s how far I’ve come in two months:

Next up, I printed out a pair of pliers. Just because!

I also lost a couple of prints during the week. For some reason the extruder was skipping steps. I tightened everything up on the extruder, re-mounted the motor and motor gear, but still had issues. Turned out one of the extruder motor wires was loose. It was being pulled too tight by the x-carriage and losing connection. So I rotated the motor to give the cables more slack, and re-connected the wires. All good!

Argh!

I was printing out the 3D-knot as a bit of a demonstration / vanity piece. However, when the print was at 77%, I accidentally disconnected the USB cable!

Unfortunately, the cable I have at the moment isn’t long enough to reach my printer, so I use a USB-extension cable which is a bit prone to coming apart.

It was looking really good, with only a little bit of lifting up at one corner.

 I noticed that a few of my recent pieces have had this lift-up issue. To combat it, I’ve made the following changes:

  • Add in a few extra shells on first layer only.
  • Drop down the nozzle so its a bit closer to the bed (0.13 to 0.18mm)
  • Reduce the ‘Additional height (ratio)’ in ‘bottom’ tab to 0.3
  • Give the bed a really good clean. There were a few grease marks causing the filament to stick badly, which would then start off the lift-off.

That’s really helped on the last couple of earbud holders I’ve printed out. I’ve also figured out how to take some really nice videos:

Okay, I’m really going to have a good look at SD card printing now.

Spool Finished

Finally finished printing the spool. Printed out the last couple of bits tonight, and assembled it this afternoon.

The most difficult part was the support arm that sits on the frame, the spindle. In its standard orientation, it wouldn’t fit onto my print area. I had to load it up into EasyFit, and rotate it 90 degrees. Currently my X-axis only has 155mm of travel, while Y has 175mm. Once rotated the piece fit on fine. However, I printed out the wrong one! I printed out this spindle, but it was too narrow, causing the spool to flop around. I had to print out the spindle from this page. It’s a bit tight, but should loosen up with use (and maybe some sandpaper.) I also printed up a filament guide.

Here’s the assembled spool. Looks great, and will keep my work-area a bit more tidy. As you can see, I’ve almost finished off my first roll of filament!

And a video of the spindle being printed.

Linear Bearings

I’ve been having trouble printing out the parts to use the linear bearings on the Y-axis. The bases have been coming through fine, but the ‘towers’ have been coming through as blobby messes. Lowering the temperature a bit has helped.

Following on from Julian’s suggestion, I had a look at the Easyfit software he recommended. Using it, I cloned the Y-axis bearing holder three times, so that I had four of the parts on a ‘plate’. My thinking was that by printing four parts, it would give the parts enough time to cool down between each layer. I set them up with 5mm between each piece, which worked great.

This was my longest print so far, at 57 minutes. This is how the parts looked when printing was finished.

 As you can see, I still need to work on my ooze settings, but the parts looked pretty good, with no melting around the ‘towers’. My theory worked well. Here’s the parts once cleaned up a bit with a Stanley knife.

I’m really pleased with them, and the linear bearings snap into them without any troubles at all. Next up was to print up an X-Carriage. The main option is Greg Frost’s X-carriage, but I went for Joem’s version, as it allows for four, not three, bearings. However, it’s very large. If it cuts down on the X-travel too much, I might have to switch to the three-bearing version. I also printed out the version with mounting points for a fan, which I think I’ll fit in the future.

This was an even longer print, at about an hour twenty. This print had some noticeable lifting off at one corner, which came up about 1mm. This won’t affect the performance of the part, but I might have to keep the bed temperature a bit higher than 100 degrees for these larger pieces in the future.