Upgrading the 3D Printer

After some TLC was offered up to Tog’s 3D printer, by way of a little restoration and tuning, it became very clear that the current hotend was on its way out.

Tog’s Lulzbot Taz 3.0 FDM 3D Printer has been deprecated and is approximately 3 versions behind the current technology. What’s worse is that the nozzles for the extruder were not standardised, byt comparison the E3D V6 style hotend and nozzles have been almost universally adopted. Even by manufacturers.

So, in case you’ve been wondering why Tog’s 3D printer has been out of action for approximately the past 2 weeks, thats why. I have started the process of upgrading the extrusion system to use an E3D V6 style hotend. Initally I tried some chinese clones (the designs are GPL’d after all!) but found their quality seriously wanting. I cannot comment on the genuine article as the order appears to have been lost in the UK postal system for the time being.

The main issue with changing from the Lulzbot Budaschnozzle v2.0 configuration to an E3D V6 is that there is apparently no models or designs we can draw from to make a mount. So I had to design one from scratch. I say design one, but actually there were many designs. The first was a laser cut wood mount – It worked but it just didnt feel like it what I was experiencing was truely level.

As I am lucky enough to have a Prusa i3 MK3 printer of my own, so I have been iterating over the design and protyping a lot of different variations to see what works. When I say a lot, I do really mean a lot…

 

I think now I have finally I settled on this design:

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The current backplate – which is already a reasonably good hot-plug-able system, is replaced with an altered one. This new one comes with a 5 x 7 grid (14mm spacing) of 4mm hex cavities which will be used as a ‘mechanical key’ to home whatever tool is installed. This way we come a little bit closer to achieving “true level”, mostly. It also has the added feature of supporting many different applications in the one piece – wheras originally it only supported the extruder assembly and the stock nozzle, this new design could even be used for things such as drawing circuits or as a plotter.

As I’ve been using AutoDesk Fusion 360 to design it, you can use this link to see the current model and download it if you so desire. It is still very much a work in progress,  however.

 

Pizza Oven 3.0

Check out some pics of the latest rev of our pizza oven, which had it’s first run on Saturday at our Birthday party.

When we built our first pizza oven in Chancery Lane, it became a regular feature of our Open Socials and other events. Having our own dedicated yard in Chancery Lane, meant that we could build a permanent one outside.

Blackpitts is an amazing space for us, but we do not have our own dedicated yard. We have a shared car park. We’ve built the oven temporarily on special occasions, but we have to take it down the next day. It’s always been the plan to make a mobile one that we could push out as-required.

Over the last few months we built that mobile version and it had its first successful run on Saturday at our party. Drop in to our regular open socials to see it in operation.

More Appliance Repairs

We are no stranger to appliance repairs at TOG. In the past we have taken part in Repair Cafe’s, and we’ve looked at things brought to us by members and visitors. This time it was a Beko DW600 dishwasher that kept burning out its water heater relay every few months. The heater should only be on when heating the water but it seemed to be on all the time, and the machine could be heard gurgling and hissing when filling. On investigation, the Omron G5 relay that powers the water heater had failed with visible burning on the case. The relay failed in the ON state.

This is a very cheap part…. less than 1 Euro. After replacing it several times a few months apart, a bigger and better relay was found after a rummage through our electronics room. A Crydom D2450 solid state relay rated at 45 Amps and zero-crossing switching no less! This should have no trouble handling the approx 7.5A that the heater draws.

What was causing the original relay to fail is not certain. It doesn’t have much air circulation where it is mounted, and the the location of the control PCB itself is very close to the hot inner door of the dishwasher. So time will tell if the new relay can handle the job.

Welder repair

An ancient proverb says that power tool failures occur in threes. During the same week that the lathe motor burned out and the compressor wire meltdown has turned it into a scary noise machine, we also had a mysterious malfunction in one of our welders. It didn’t release any smoke, didn’t make weird noises. It just didn’t weld. 0 volts across the output.

Inside of the welder (top view) before the repair attempt. Note that a large number of similar – but not identical – top boards can be found on Aliexpress.

This machine, a small 180A TIG/MMA inverter welder, has recently been repaired. It was not used heavily, as TOG has only so much use for welding. In fact, it was only used by a couple members to practise their welding skills.

On one hand, this machine was 5 year old, has been used extensively in the past and could have been written off as death of old age. The cost of a commercial repair would probably exceed the value of the welder. On the other hand – why not try to repair it ourselves before scrapping it?

Continue reading “Welder repair”

Project: Lasercut Fridge Magnets

Its been a while since this blog had some laser-cut goodness. This latest project is to create fridge magnets for a members event.  The design uses the Alpha Thin font and features a person holding some fire poi.  

After the cutting them all out of 3mm Birch Plywood, we marred them to magnets to with some glue.

 

We used Dry Erase White Magnetic Strip Roll, as we had it on hand. To glue them together  we used our new favorite glue, Mitre Fast Adhesive.

For more photos of the build, visit our gallery. If you would like to do you our laser cutting projects do come along to one of our CAD nights. 

 

More Ebike Fun

We’ve posted before about our tinkering around with Ebikes. One of our members had a faulty Ebike battery.  Opening it up, the battery management circuit was found to be toast. We sourced a new one online from China, fitted it, and the battery is back up and running. We are thinking of making some spare batteries from old laptop batteries. We’re also thinking of having a TOG loaner Ebike. If you have any old laptop batteries that you could donate to us, we’d be interested. If you’d like to take a look at our Ebike works, drop in to our regular Monday evening Electronics night.