This is the continuation of my attempt to build a 3D printer with a minimum budget of around $400 using new and recycled parts.
The Y-Axis will consist of a moving build bed which means that the part will be moving and as long as velocities are not too high it can prove no problem. A handy glue stick on the glass or some printers put a coat of hairspray to lock the part down as it is being built.
The bed plate will slide on 3 linear bearings on 16mm steel rods. The two rods are mounted to the base frame with aluminum shaft supports. The blocks are bolted in oversized holes to allow alignment. Vertical alignment is done with thin shims under the blocks. The rods need to be parallel to each other and perfectly level to the vertical frame.
If you wonder why three bearing and not four is that it reduces shuttering or any binding that might show up. A flexing hose to protect the rod would keep trash out of the bearing that I am thinking about too.
As I have mentioned before that I work at a screen printing company and the machines that print the shirts have aluminum pallets. I was blessed to find an old one not being used. The size was 6mm thick X 355mm wide and I cut the length to 320mm. It has a mounting bracket under it and is un-removable but it just makes it stronger. The size will give me room to grow the build bed to a very large size some day.
The rods were harvested from an old HP 5500 large format color printer. I was really hoping to use more parts from it but it was very custom built from Germany. Many of the electrical components run at 24 volts some run at 33 volts. None of the stepper motors can be used. It was a great printer in its day but when a 15-year old printer needs $1200 print heads it is time to stop.
Waiting for funds and shipment for the mounts and bearings but as the photo shows the rods and plate are cut and ready to go. I can not wait!
What a glorious day that celebrates the spirit of Easter for a Geek. I got to order my parts for Step 3 and Step 4 of the build.
It will take about a week before they begin to show up but what a milestone. Sacrifices had to be made for this to happen. I had a beautiful 44″ wide Epson printer and as that got sold and picked up today, it made room for my new chapter.
Build cost for this section from Ebay Seller leap3d and giorgio11185
- $0.00 – 1 – Build Bed Plate Aluminum (Scavenged)
- $0.00 – 2 – 16mm X 780mm Steel Rod (Scavenged)
- $9.96 – 4 – SK16 Linear Rail Shaft Guide Support 16mm Bore
- $22.85 – 3 SBR16UU 16mm Aluminum Open Linear Router Motion Bearing Solid Shaft Block
- $10.00 – 28 – Bolts with nuts and washers
- $42.81 – Y AXIS SUB-TOTAL
- $50.00 – FRAME SUB-TOTAL
- $92.81 – TOTAL SO FAR
What am trying to do is very hard and bound to lead me to stumbles. My first one was simply not watching the details of the clearly marked title for at linear bearing. I was so excited to get to order I overlooked the size, not being 16mm. The first order of parts and my heart just sank. If the bearings are not on the rods I would not be very far into the build at all, basically shutting down the completion of this section.
So I emailed Leap3d and they were so easy to work with. At this time they do not carry the 16mm bearing so I found giorgio11185 and reordered. That puts it about a day or so behind the supports. That is OK, this project does not have any deadline, it comes as it comes. I just watched a documentary about a train system being built in the harsh conditions of South Africa, the builders are facing daily challenges that strain their deadlines and budgets. Land bridges for the tracks are being built to cross sections of soil that have been known to have sink holes, incredible.
Each foot of progress leads to a mile and each mile finishes the whole. My project did not come as a kit packed in a box with instructions. Nor did I come up with something that no one has ever built. But I did throw my spin on the details that make it mine. I have the confidence to know that it will be a success and unique but not without a lot of research.
The assembly that has always worried me is the precision of drilling the bolt holes. After actually sliding the real bearing on the rod and feeling the tolerance of angle it likes to be really straight. Mis-alignment will just put drag into the movement, which translates to undo strain on the motor and possibly missed steps.
My methods that I describe may not be modern working practices they are just my skill level and very crude supply of hand tools and somehow it all works out.
So let us break it down and the thought so far is to mount one rod and align to that.
I carefully laid out lines for the holes on the bed, used a sharp pointed punch on each crossing line and cut small guide holes before the final size is cut. This reduces movement in the bit as it starts to cut. The bolt holes in the bearings dead-end at 10mm, so with the thickness accounted for, I got M5-12mm bolts and that gave me about 6mm of bite for the threads.
With the one rod mounted to the bed, I attached the rod to the printer frame with the shaft support blocks.
After working on this section carefully, cutting each hole and checking the distance between the rods, I have good news. It slides with tight bolts!
Thanks for hanging in with me.