Posts

Showing posts from September 23, 2018

Laser cutter speed difference

Image
Here is the video of my two laser cutters cutting the same tile side by side. It prompted a few people to ask 'how come the 30W tube is much faster than the 100W tube?'

I picked the new laser cutter based upon speed. It had a few specification stats that suggested it was fast and the photos showed a fairly lightweight head etc. Now that I have the laser in my possession I can see all the design decisions that make it fast. In the case of these Carcassonne tiles I only need the full power of the laser when I'm cutting the tiles out.

The low power engraving lines are done with minimal power, only 8% of the 30W tube. The metal RF tube gives me much more control over the low end power, the head can fly around at 100mm/s, twice the speed of the larger machine. The engraving can be done at 1000mm/s, again nearly twice the speed and empirical evidence suggests that it is actually moving at that speed.

The 30W laser can easily handle the 3mm poplar ply wood at a sensible 35mm/s, t…

Laser cutter comparisons

Image
I finally dialled in my new laser cutter this evening, I had some minor issues with the bidirectional engraving lines not quite lining up. I also spent some time testing out speeds and powers to see exactly what it's capable of, now I just need to figure out how to take better pictures in the evening.
The tile on the left was cut on the old laser cutter (100W glass, 600x900mm) and the tile on the right was cut on the new machine (30W metal, 300x500mm). Both tiles are actually very comparable, the 100W obviously makes deeper and darker lines. The engraving colours are close enough and with a little more effort could be identical. The 100W slightly breaks through the sheet on the corners where the head has to slow down to change directions. There are more cut marks on the underside but that's because the 100W honeycomb is filthy.
Even with these two tiles being so comparable there is one hugely significant difference. The old laser cutter cut the tile in 2 mins 13 seconds and t…

Mounting the Wemos D1 Mini

Image
I use the Wemos D1 Mini for all of my wifi based projects, such as the remote control Strandbeest and the Stranger things light board. It's a powerful little board that exposes the ESP8266 via a USB to Serial converter and it can be set up to run from the Arduino environment. It's also really cheap and can be bought for less than $2.50 so if you want to make something remote controlled it's a bit of a no brainer. The trouble is that the board doesn't have any mounting holes so it can be hard to attach to a project.
While looking to affix my board securely to my projects I realise that there was a gap to the left and right of the ESP8266, either side of the antennae that didn't appear to have any copper or tracks running through the area. The board is only a 2 layer design so it should safe to drill directly through the PCB and use this as a solid fixing point. A quick test later on a sacrificial board showed that this was indeed possible and although adding screws…

Extractor fan cleaning

Image
Given that I have to clean my extractor fan every six months I'm surprised that I can't find a post about it. There is a grill over the front of the extractor fan which clogs surprisingly quickly when cutting wood but this time round, cleaning the grill didn't seem to improve the extraction so I had to dig a little deeper.
Inside the extractor fan is a large impeller blade, this sucks are in to the middle of the fan and flings it out to the edges, it rotates around the edge of the fan and then out the hole at the bottom. The smoke contains vaporised wood particles which is surprisingly sticky, this coats every surface inside the laser and eventually reduces the efficiency of the fan.  


The impeller blade is held in with a single bolt in the middle. The motor shaft and corresponding hole in the impeller are 'keyed' so that they turn together. Do not lose this key when you take the blade out. With the blade removed it is a lot easier to clean up the blade and areas …