Gina

I feel a bit nostalgic about my Titan printer as it was the first printer made from scratch to my own design although it has been much modified since the first build so I guess it isn't really the original design. Also, guess it's daft to conserve something with highly usable parts some of which are quite expensive just for the sake of nostalgia...

Should be earthed then.

Was it the metal frame that was live? I would be inclined to earth it - connect a wire from the frame to mains earth. I wouldn't be inclined to leave it printing unsupervised though.

That's bad!!

It wasn't my topic but I guess I'm the noisiest owner of 3D printers on here! ?

I think I have now "borrowed" all I can from the Giant printer. I can't "borrow" the wheels as these are all of a larger size than the ones required for the Concorde printer and I have now run out of spare small wheels. It has now come to the stage of needing to demolish the Titan printer to gain parts for the printer that is replacing it. Titan will be no more when the Concorde is built and Concorde will do all that Titan has done and more. It was always intended that the Concorde should "consume" the Titan printer. I shall still have my Mini printer while Concorde consumes Titan so won't be without a 3D printer.

I am well experienced and qualified in handling mains voltage equipment as well as higher voltages and power. I am very careful and aware of safety. The bed heater is controlled by a Solid State Relay rated at several times the current and controlled by the printer control board (Duet WiFi). All the PSU mains connections and the SSR are covered by protective covers and the printer normally never plugged in without these covers in place. This doesn't mean that care isn't still need though - a screwdriver dropped onto a circuit board could easily short out a high current supply and cause a fire. Except for specific testing or faultfinding the controller board and all other electrical connections are covered. All wiring interconnections are insulated with heat-shrink sleeving. Also, all metal parts are specifically earthed to the mains earth so any leakage should trip the ELB (or whatever you want to call it) and no metal parts can become live.

I don't have that problem, at least not yet but I do have other problems...

There can be some serious currents and chance of fire in 3D printers. For instance my Giant printer uses a 1200W bed heater (400mm x 400mm) at mains voltage - that's 5A and plenty to be a problem if not handled really well. Many 3D printers use low voltage bed heaters at much higher currents. The hotend heater is also capable of causing a fire. I don't wish to frighten people from using 3D printers but IMO safety is paramount. There are safety arrangements in the firmware of most 3D printers where the power is turned off if the heaters don't operate as expected but... Nowadays everyone should have a working smoke detector and also CO (carbon monoxide) detector, regularly tested, to warn the occupants if anything goes wrong. And yes, the appropriate fire extinguisher is a good idea.

I have several too.

I have used crimped connections perfectly satisfactorily. You do need proper crimping pliers though. Properly done crimping is more reliable than soldering.

One advantage of building you own printer is that you can make sure everything is up to the job. OTOH I know not everyone is able to build a printer.

I agree about connectors. Many are rated far beyond their capabilities and this is concerning me in my new printer build. Connectors with tiny pins are rated at 3A. Apparently plenty for a 60W 24v hotend heater drawing 2.5A but I'm not convinced! I don't want anything not 100% reliable and I don't want anything that could get hot through carrying too much current.

Before I mount the Z motors I shall need to find some suitable wooden block or wheels to raise it off the floor. Empty filament spools will do - I have no shortage of those - one at each corner. That'll do for the time being.

Cut one of the metre threaded rods in half for the Z drive, so I expect the 500mm rods to show up now! ? Also, cut some extrusion to length for the X rail and made holes in the base of the box for the Z rod couplers. 3D printed X motor mounts and the front and back plates for the X carriage.

Same here. Been using them for years plus their excellent Titan extruder after trying others including my own make. I use a V6 hotend on my Mini printer and the E3D Volcano hot end on my Titan printer (I had the name first!!) and the new Concorde. My Giant printer uses my own design and make of hotend.

X Carriage with extruder and hotend plus Z probe. I have left the cover off the extruder to show the inner parts.

As I continue to build the new Concorde printer I'm running out of 3D printer spare parts and now "borrowing" parts from my Giant printer whilst retaining operational Mini and Titan printers until the last minute. I shall need two of the more powerful stepper motors from the Titan to drive the Z drive rods, I think. I plan to keep the Mini printer for the time being as it works fairly well for small parts up to about 200mm square. I shall probably use the ready-made cables from the Giant printer to get the Concorde working and replace cables with the right length ones once it's working. This means I can run the new cables tidily as I go along. I have a new 2.85mm hotend and the extruder from the Giant on the new Concorde X carriage and the 1.75mm hotend from the Titan will provide an alternative interchangeable hotend. As all the extruders are the same, so are interchangeable, the Titan one will probably go on the Giant later.

I already have lots of this type of connector which they claim is rated at 3A but I don't think I'd be happy to put the 2.5A hotend heater current through them!

Currently printing the X carriage. Been trying to think what sort of connectors to use for the interchangeable hotends. My Giant printer uses Molex connectors as used in computers for DVD drives etc. but I'm not happy that these are good for this application. For the Concorde I need 2 pins rated at about 3A for the heater and low current 2 pins for the thermistor. The connectors need to withstand the vibration of printing and I would like the sockets to be fixed to the X carriage. I'm now considering small spade connectors but am open to suggestions. Other ideas would be much appreciated.

You should never put anything solid in your ear... Pardon???

Spool holder bolted onto base. The reel of filament fits under the bed and doesn't take up any usable space. Filament will be fed to the extruder in PTFE (Teflon) tube.

Z rails screwed in place and Z carriages attached to bed frame.

Connectors on DSLRs cause a lot of problem,s in my experience ?

I can now calculate the best position for the Z rails so that the centre of the printing area is in the centre of the bed. I have measured the Y range as 450mm. Better than expected. With the E3D Titan extruder the nozzle is 13.5mm in front of the base of the extruder ie. front of X carriage. X rail is 20mm wide so mid point to front is 10mm. 1mm gap and X carriage is 5mm thick giving a total of 10+1+5+13.5 = 29.5mm. Y carriages are 75mm wide and rear pulley blocks are 30mm. Thus furthest back the nozzle will go is 30+75/2+29.5 = 30+37.5+29.5 = 97mm from the inside back of the box. Y range = 450mm so centre of bed wants to be 97+450/2 = 97+225 = 322mm from inside back of box. OR on the outside of the box (easier to measure and drill), 322+18mm(thickness of ply) = 340mm. I shall make up a template for this to ensure that the Z rails are exactly vertical.