So the guide I'm looking a following says to use m5 threaded rod (5mm) as the way to elevate the z axis up and down. A problem with this that I can't easily buy m5 in my part of Australia. An alternative is to buy a different but similar part called a lead screw. This would appear to be the same cost to me, but better.
This video talks about lead screws and considerations.
Looks like I have more parts to buy and also there is a Black Friday sale, whatever that is, on Ali Express. After much examination, looks like I want these NEMA 17 motors from Stepperonline. I'll save like $3 in the sale, which is about 3/4 of a cup of Melbourne coffee.
These motors seem to have enough torque, seem to be ok for noise, are broadly recommended and sell direct on AliExpress. They are rated 12v to 24v. I going to attempt a 24v build, but if that doesn't work out it appears I could change my mind and make a 12v build by replacing the Hotend and setting my heated bed to 12v instead of the 24v setting. The Prusa i3 MK2 was 12v, but the Prusa i3 MK3 was 24v, which is my influence.
Stepperonline have an Australian store with stock, but they didn't seem to have the motors I was after for a good deal. They do have power supplies for Australian use, and also steel L brackets for mounting the motors which I'll seek advice about. Seems like they get some local AU business from me too.
- BigTreeTech SKR v1.4 bundle, $81.60
- V6 All-metal Hotend, $19.96
- Heated bed in 3mm instead of regular 1mm, $20.54
- Thermister for heated bed, it didn't come with one, $3.15
- Cheap end stops x 6, $7.11
- A 3d printer cabling set $5.99
- Probably these stepper motors
- Maybe these stepper motors if I read that more torque is actually useful:Maybe these stepper motors if I read that more torque is actually useful.
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.
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?
I've opened my 3d printer and used it finally, during the in the 112 day Melbournce, Victoria, Australia lockdown. It is fun, but needs some fixes, but these can be printed by the printer itself due to clever designs.
I have a Monoprice Mini Select v1, the specs are here.
Spare extruder parts
Apparently the extruder clamp/ arm thing has been know to break on my printer, but here are the patterns for spare parts!
Drilling Free heat bed reroute with cable chain
There is another design fault on my printer were the routing of the heated bed wires rubs against things and needs eventually to be rerouted. This extremely clever design prints in several piece that snap together.
Here is a picture of a ring that I'm about to do some mining in.
Trade route helper rogey
Find places near you to mine expensive materials to sell like Panite and Low Temperatue Diamonds edtools
Plot jumps using neutron starts to have fewer jumps. spansh
Find closest stations to buy ship upgrades inara
Find closest station with a Material Trader or facility. inara
Deadlift 72kg / 158lb (5 reps) Back Squat 54kg / 119lb (5 reps) Bench Press 40kg / 87lb (5 reps) Barbell Row 40kg / 87lb (5 reps) Pull/Chin-ups 10 reps Military Press 14kg / 32lb (5 reps)