I've had a lot of lockdown time, and have plenty of time to think about building a 3d printer, with some parts being printed from my current printer. Melbourne lockdown was 112 days, the second lockdown. We are currently at a run of 8 days of zero cases, or "doughnuts" as I've been calling them.
People have videos and blogs building a variety of 3d printers, from hobbyists as you would expect.
- A 3d frame metal printer using a board that looks good
- A 100% accurate Prusa i3 MK2S clone, which looks like an expensive option
- Building a cheap MK2 like I want to
- Toms3d youtube videos of his cheap MK2 build>
- Toms3d blog about building his cheap MK2 build.
The Prusa i3 Mk2 or MK2S looks somewhat achievable, or at least using the frame, axis head etc, but changing the controller board and using better stepper motot drivers. See the github source for the MK2S here, which includes a DWG of the frame. There are files that let you try and print a frame in pieces, but I don't think this will be very satisfying. Seems like this won't work that well.
The Prusa guide for the assembly of the MK2S is here.
A youtuber Toms3d has a BOM for their build here , and good instruction video series here.
I like the idea of using PETG as the plastic. Aparently PLA isn't good over the long term. ABS is smelly to print, I read. I like the look of this cyan PETG.
The Prusa i3 Mk2 base has is plastic parts and threaded rod. Bunnings in Australia stock m10 and m8 threaded rod, but not m5 threaded rod that I could see, only m6 rod.
I'll try asking for a quote for a variety of rod from some out-of-my-Australian-state vendor. They have listings for small bundles of rods on ebay, so maybe they do small orders even though they require quotes. sun stat fasteners
The real Prusa models use a laser cut aluminium plate for the Z axis. I've asked friends, I don't have access to a laser cutter or large CNC machine, but even if I did buying a large plate of aluminum isn't very cheap when I only need a smaller piece. A friend has a smaller CNC machine, but it won't fit 400 x 400mm. So no metal plate in my build.
So for my Z frame I'm thinking about buying a stiff, think bamboo chopping board. Baboo grows round, so these boards are industrially compressed. It looks like I'll need to modify the design to make the board thicker at the bottom, or perhaps just not to cut the V shape like the aluminium original, and to use two holes and two small u shapes.
This chopping board is good but reasonably price and good looking at $26 AUD.
With 11.11 day comming up on aliexpress, I should buy electronic things shortly.
For $75ish AUD I can get a controller board, drivers, and a small screen. Seems like a good deal. BIGTREETECH BTT SKR V1.4 board with a screen smaller and TMC2209 drivers which appear to be very quiet. Also for some a little more money can get a similar bundle but with a bigger screen. However I don't see the screen as that important, so I'll probably go with a smaller one.
Going to need nema 17 stepper motors, cheap at about $45 AUD. These seem like a commodity item if you don't have a specific torque requirement.
A "hotend" printing head for less than $20 AUD, also cheap.
Power is confusing me, which isn't good. Seems like you get everything as either 12v or 24v. Hmmm. My preferred board and driver support 24v, so perhaps I go 24v.
This Australian stocked 24v 20a power supply with a 1 year warranty looks good.
Hmm, a heated bed?
No comments:
Post a Comment