Looks good - you’re making nice progress.
Loving it, It really does look great.
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So being the last minute person I am at times, I am now thinking about the wire to supply power to the hotend heater cartridge. From what I see, a fine strand wire with braided insulation would be the best from a flexibility standpoint.
Where do others buy such wire? Digikey does not have it from what I can see. I’m thinking 20 or maybe 21awg aluminum wire.
How much current do you expect to run through your wire? Also, why aluminum and not copper?
If you’re looking at 2A, then 22 AWG stranded copper will be more than acceptable. Note that while aluminum wire is 50% lighter, it has 60% of the conductivity of copper so that the weight will work out the same. Aluminum is also more brittle than copper so I wouldn’t recommend it in a situation where it is going to move back and forth.
I’ve never found a great vendor for wire; I’m sure there’s somebody out there that has lots of stock and phone/web support but I haven’t had luck finding them.
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Basically because I think that my Enders use aluminum, so I assumed it would be better, but if copper is that much better, then sure, copper it is.
2amps is probably close to what the current will end up being.
I guess I will keep looking.
Aluminum is cheaper, don’t assume it’s better just because Creality uses it.
That’s very true.
would love to see a print on this. print a longgg benchy
Haha! Definitely wouldn’t be a speed benchy!
So it’s time for next update.
I mounted the extruder; turns out the included mount works. It’s not exactly as designed, but once this printer is actually running, if that position works like I think it will, I can design a nicer mount.
The mainboard housing is designed and mounted. The lid for it will include the mount for the touchscreen. The lid design still needs to be finished.
The bed heaters are going to be supplied through two mosfets. One will be in the mainboard housing beside the mainboard. The other will be in another housing on the opposite end of the bed. Said box is already designed, printed, and mounted, and will have its own dedicated cooling fan.
Cable chains are mounted, and have some wires already routed through them. Once again I am being somewhat hampered by me not ordering some components far enough ahead, so the wiring is having to wait a bit. Not a big deal though, the supplies should arrive this week yet. I have other parts of the printer I can work on in the meantime.
I changed the design slightly on the Y belt tensioners to rectify a design flaw, and printed and mounted the updated models.
I also tackled the job of insulating the bed. First I placed all the foil backed insulation in place, then secured it with a copious amount of foil tape. If for some reason the heated bed does not work, I will not be very happy if I have to redo that project! It’s not a very pretty job, but it should do the job. Once the printer is done, if I am having to look at the underside of it, it will mean that I have bigger problems than the appearance of the insulation job.
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Will the heat bed be able to heat sections like what Prusa has done, or just the whole thing?
Well, it certainly won’t be able to automatically turn on only the sections needed, but your question does give me an idea. I could easily put switches on the lines running between each heat mat, and the mosfet. The mat that I will be using the thermistor on will not have a switch of course, but the other 5 could.
Thank you for that idea, looks like it’s shopping time for me again!
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Makes sense now heating the whole bed if you don’t need it. I just parroted a idea but I’m glad it was useful!
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Well, today I finally did a test I have wanted to do for a long time. I tested the heated bed setup for the first time!
I turned the PSU down to 10V, which should equate to just over 300 Watts for the entire bed. I temporarily hooked up all the heat mats directly to the PSU outputs, and powered it on. I measured the temperature using my multimeter and included thermistor. It took just over 20 minutes to get from 20°C to 60°C. I left it powered on for a few more minutes till it got to 65°C, at which point I knew I had easily enough margin.
It is really nice to know that I have enough power to make this work. I imagine the marlin firmware will need some tweeking so the thermal runaway detection still functions, but doesn’t give false alarms all the time.
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Well, it’s been quite a while since the last update, but it isn’t because I forgot to or decided not to. I simply haven’t had the time or the inspiration to get it down from the shelf and start working on it. The busy season is upon us again on the farm, so progress probably won’t be very fast for a while, but it is progress at least.
I managed to get all the wires running from the terminal blocks to the heat bed routed. That was definitely nice to get done so I didn’t have the long wires hanging in harms way. I need to get the 12v power supply lines that run to the mosfets made and routed, but I found out I didn’t have suitable plugs for the wire I planned to use, so I now have new plugs on the way.
In the meantime, I routed and finished the connections on the wires for the hotend heater cartridge and thermistor. I also routed the wires for one of the hotend fans, and the x and y stop wires. I managed to (once again) not make a good enough tally on the supplies required, so I’m waiting on more wire for the z stop and the other hotend fan.
It’s not a big deal though. In the meantime I need to design and print all the mounts for the end stop switches. I can also put together and route all the 24v power supply lines. The hotend shroud needs to be printed and installed as well. I’ll also need to design and print the screen mount. I should be able to keep busy while I wait for supplies. Hopefully I can keep up the momentum now until this project is across the finish line.
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Does anyone know if it is possible to set the thermal runaway time longer for the bed and leave the time for the hotend as is?
Edit, nevermind, I assumed that thermal runaway detection would take issue with the slower heat up time. Turns out it doesn’t. If I don’t turn on the 12v power supply so the bed won’t ever heat up, then thermal runaway detection does complain, so I know it works 
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Well, planting is done, and I now have more free time. I did have some free time during planting which was partially consumed by troubleshooting issues with the bed leveling on this build. Since that problem is now fixed and firmly behind me, I managed to make a fair amount of progress.
The magnetic build surfaces are installed. All the wiring is complete, with the only exception being the possible future addition of a filament runout sensor, as well as a little bit of tidying up. I need to design the top for the main electronics housing, which will include a mount for the screen, as well as the mounting points for two electronics cooling fans.
Things are getting quite close to the point of doing some test prints. Initially I will probably set the printer on a table in the open to get everything fine tuned and work the bugs out. It’s a bit of a pain to move this beast, especially in and out of its planned permanent home, so better to do the bulk of the fine tuning where it’s easily accessible. Besides, there is also some work that needs to be done before its permanent home will be ready to host this printer.
All in all, I’m really starting to get excited to see how this machine will work!
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Well, yesterday an exciting project milestone was reached! I started the first print. It was just a 1265 by 5 by 11mm cube that I printed as a first dimensional accuracy test, as well as to see how well the ABL worked. The print completed successfully overnight. A few minor tweaks to be made, but overall, highly satisfactory to me for a first print. I’m currently in the process of printing calibration towers to determine optimal parameters. I’m going to try upping the top speed(but not accelleration) to see how much it helps on the long length prints.
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Just started reading this thread.
Gotta say, that looks very impressive! I’d like to take a try at building a larger format printer but with my side business being busy I don’t seem to have the time.
Looking forward to seeing how you progress in the future.
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