mhackney's 3D Printers

[mhackney]

Lee, thanks. Also, could you post a photo of the Prussa linear bearings? I'm curious to see what they look like.

cheers,
Michael

[LeeWay]

Like thousands of ebay listings and first builds on the Zone, they are simple unsupported round rail bearings. They fit Drill rod very well.


Here is an Ebay listing.

12pcs LM8UU 8mm Linear Ball Bearing Bush Bushing | eBay

[mhackney]

A little soldering completed (and documented). First the Thermostat. It is actually a Velleman Kit (MK138) that comes in its original packaging and instructions. I just documented a few tips.



And the Heating Resistors soldered in parallel:



And I think that's it for getting all the sub-assemblies finished! Now its wiring up the driver board, that funky little red board, the thermostat, hot end and motors. Then I should be ready to test.

cheers,
Michael

[mhackney]

That "little red board" is an easy driver stepper driver for the extruder stepper.



Michael

[electronrancher]

You're going to want to use crimps on those heater resistor leads, and on the wires you attach to them - they get hotter than the melting point of solder and can fall off.

[mhackney]

I've read that too. Any suggestions on how to route the wires to the hot end/leads?

regards,
Michael

[electronrancher]

I used to run the heater and thermistor pairs along the extruder cable and down to the electronics. But recently I mounted the Vellman board up on the extruder carriage and now I just run one pair down for 12V DC. Then the leads from the heater and thermistor are just a couple of inches instead of a couple of feet.

Watch your clearance to the belt with those wires. I zip tied the pairs to one of the hot end mounting holes, which made me feel a bit safer about not ripping the thermistor out. The heater would just turn on all the time and slag the hot end if the thermistor pulled out or came disconnected.

[mhackney]

Thanks electronrancher. What machine do you have? The big challenge on the H-1 is the lack of space between the X carraige bearing mounts where the hot end and extruder mount. There is very little clearance to route the wires from the heat resistors out and back. But, all that said I did get it wires up. The challenge for me is to do it in a way that can be documented in the manual I'm writing so others can replicate it.

So I'm all wired up and ready to plug it in and configure Mach...

Tomorrow!

Cheers,
Michael

[rwskinner]

I set my resistors up exactly like that and soldered them. It last less than an hour and the solder dripped off the connections. I then used some crimp ferrules and hadn't looked back. I'm just trying to save you a headache later.

Richard

A little soldering completed (and documented). First the Thermostat. It is actually a Velleman Kit (MK138) that comes in its original packaging and instructions. I just documented a few tips.



And the Heating Resistors soldered in parallel:



And I think that's it for getting all the sub-assemblies finished! Now its wiring up the driver board, that funky little red board, the thermostat, hot end and motors. Then I should be ready to test.

cheers,
Michael

[mhackney]

Thanks rpovey. I know any of us can get this thing together from just a photo and some drawings. But there are a few little details that are worth knowing up front. The latest, once you have the extruder assembly ready to install you'll find very little clearance for the hot end between the triple-double bearing blocks that make up the X carriage. Simply urning the screws around on the left side block so the heads on both sides face "in" give you that little extra room you need. Steve at SeeMeCNC told me yesterday that they turn the bottom screw that actually interferes around - you can do that after the machine is built too. But why not just do it right the 1st time.

cheers,
Michael

[mhackney]

Hey Richard, I changed mine also and will document using crimp connectors. That was an easy thing to change and eliminates a problem area. I presume the thermistor leads can be soldered? They are much skinnier and would be tricky to crimp.

Cheers,
Michael

[lerman]

I used to run the heater and thermistor pairs along the extruder cable and down to the electronics. But recently I mounted the Vellman board up on the extruder carriage and now I just run one pair down for 12V DC. Then the leads from the heater and thermistor are just a couple of inches instead of a couple of feet.

Watch your clearance to the belt with those wires. I zip tied the pairs to one of the hot end mounting holes, which made me feel a bit safer about not ripping the thermistor out. The heater would just turn on all the time and slag the hot end if the thermistor pulled out or came disconnected.

If I were designing something like this, an open or shorted thermistor would cause a shutdown rather than an overheat.

Ken