Friday, 19 April 2019

Mini filament review

For the last couple of days I have been printing some signs.
They are mainly flat with raised lettering.

Due to various failures I have been trying different types of filament among other things to fix the issues.

The results have led to some conclusions and preferences.

In order of preference: PLA Plus
This is the best at the job so far. It stays flat on the glass with no warping even on the largest size flat prints.
It's not perfect though. The end of the spool is wound so tightly that the Ultimaker 2+ extruder struggles to get the last half dozen layers of coils off of the spool. That's a lot of wasted filament!
My guess is that the tight loops press against the inside of the Bowden tube so I can't even use it loose from the spool.
Heat to 225C with bed at 45C.
The results have a nice tidy surface finish with sharp edges.

ColorFabb PLA/PHA
This was a lot better than standard PLA. It stayed flat on most prints but a slight tendency to curl.
I get best result running it hotter than the suggested.
For me 215C with bed at 60C works best.
The surfaces are nice and tidy. The raised details hace a very slight bulge at the corners. If I was not comparing to other prints I would not have noticed. PLA
This would not stay flat. Even before it had done the third layer the edges of the brim were curling up and by the time the print had finished, the main body had lifted by a couple of millimetres at several corners.
I've used this successfully on other prints. It just does not like the thin flat prints.
Heat to 210C with bed at 60C


As far as fixing the various issues, I think the glass is the main problem.

I think there is a slight inconsistency in the glass thickness. If I avoid printing on the rear right quadrant of the print bed, I get much more reliable results.
The affected areas extends about 50mm from the right hand edge to about half way forwards.

I managed to avoid this by rotating the largest prints and they have all worked since.

I plan to experiment with bed levelling to see if by deliberately setting a greater distance at the front left corner I can get better reliability at the rear right.


The first issue I found is that my nozzle was either worn or clogged.

The filament would flow for a while then get straggly.
I replaced the hot end nozzle and that cured it immediately.


Sunday, 14 April 2019

Bifold gate

In preparation for Shelley opening her garden for the National Open Garden Scheme, we have been doing a lot of tidying.

To create a temporary back stage area, I have made a bifold gate out of some doors I had in storage in the shed.

At the moment the gates are latched back against the rear of the stables. When we have arranged some fence panels to hide the pallets of haylage, the gates will come in to action.


Sunday, 7 April 2019


I've made a couple of box style shelves.

One for the kitchen, to put the wifi and Sonos on.

The other is in the study, to house the speakers used with the Xbox.


Friday, 5 April 2019

Fender enhancements

We've carried out a couple of jobs, over the last week, on Fender.

I've added the letters back to the front, with a slight but significant change.

Dean made a very nice set of hoop sticks for the back including a leaf motif.


Tuesday, 2 April 2019

2020 T-slot GX16 enclosure

I have a small CNC engraving machine which I am going to use as part of the proof of concept for my project to convert a Shapecut oxy gas cutter to CNC.

I am deliberately using a more powerful CNC control box than is necessary for such a small engraving machine. As a way to keep the larger cables tidy I have made a small enclosure to mount on to the 2020 T-slot aluminium extrusions. The enclosure fits three GX16 aviation style connectors, which are used for the X, Y and Z axes, and a GX20-4 connector, used for the spindle of the CNC machine.
Initially I made a box that fitted only the three GX16 connectors which I then expanded to fit the GX20.

The 4 pin GX16 sockets are sized for use with NEMA23 stepper motors and are suitable for up to 5 Amps. They are far larger than needed for the tiny engraving machine that I am currently connecting them to.

I've selected a GX20-4 pin connector for the spindle, not because it needs 4 pins but because the individual pins are only rated at 10 Amp each. I can double up the pins to allow for the 20 Amps that might be necessary on a larger router spindle.

The enclosure can be bolted to a aluminium extrusion using either M4 or M5 drop in T-slot nuts. Typically the M4 size fits the 2020 profile extrusion.

The bolts hold the lid closed as well as holding the box to the rail. There is a small tongue and groove detail along the top edge to ensure that side of the lid stays in place.

I 3D printed them, on their backs, without any supports.


Shapecut Series:
Part 1 - Magic Eye to CNC
Part 2 - CNC proof of concept design


STEP, Fusion 360 and STL files (Zip)
Licence attribution - small business exception

My designs in the Fusion 360 Gallery.
My models in the GrabCAD library.
My designs on