- This topic has 16 replies, 4 voices, and was last updated 9 years, 6 months ago by
.
-
Posts
-
-
I noticed these notches cut into the bottom of the support arm and I was wondering why they exist. My printer’s a bit misaligned and the split is having problems with adhesion.
-
-
-
Speaking of those notches….
I was looking at the Configuration.h file today, and I noticed that the inner arm length and outer arm length are established right there at the top. It set me to wondering – If I wanted to have a larger build platform, would it be as simple as building appropriate arms (say, 200mm), changing the parameters, and recompiling the firmware? My hopeful self is encouraged, but my cynical brain, scorched by long experience, bets otherwise. (Optimistic self also wants to paint 3m by 3m pictures in the street using the SCARA mechanism.)
-
-
-
-
Quentin, I’ve been working on my own Morgan clone based on your design. First off, a lot of the engineering decisions you’ve made become obvious when you dig into the design.I can see there’s a lot of thought and work in the Morgan, so congrats and thank you for your efforts.
Q1: What made you decide to install the Psi arm on the threaded rod instead of the tube? It seems like the tube would better support the weight of the print head and reduce sagging.
Q2: I’m planning to replace the upper tube bearing with three 608 bearings to simplify the BOM. Thoughts?
Q3: I’m also working on replacing the print head bearing with a single 608 and moving the print head to the side of the outer Psi arm (perpendicular). I haven’t dug into the interpolation code yet, but I’d like to think 90deg and an offset wouldn’t be too big a deal. If it works, a second print head might not be too far off.
Q4: I’m also working on replacing the smooth rods with angle iron, which I intend to use as two legs of a 3-legged table (ditching the PVC and associated feet). Are there any problems with that approach that you can see?
Thanks again!
-
Thanks!
A1: Mostly arm placement. I have been working on a new set of arms that will be anchored on the pipe for stability, will post photos of it by next week.
A2: Interesting… How?
A3: You can make it work by just making the opposing arm proportionally shorter as well. This will keep the code the same.
A4: The current triangular frame gives it the stability in that the frame is under stress. Removing the stress and triangles will introduce wobble. Wobble brings unwanted artifacts. Your job would be to combat those.
Best of luck on the build! Pictures mandatory…
Q
-
2: Like a lathe steady rest:
3: Thanks. I’m not quite there yet, hopefully this week. I’ve been dealing with printer issues and finally have a set of decent drive wheels.
4: That’s what I kinda figured. I’m gonna have to get creative and see if I can stabilize with less hardware. Have you considered guy-wires?
-
2: Does the bearings ride on the pipe, or is the bracket attached to the pipe and the bearings run inside a hole?
If the former, you will just need to ensure your pipe is perfectly round to prevent inaccuracies.
4: I did try them initially, but they stretched, and I kept having to adjust. The triangular config followed, so I cannot say if I gave it enough time. Perhaps if you use pre stretched wire it should be good.
-
2: I was planning on a direct pipe/bearing interface so that’s good to know. I’ve got some 3/4″ round welded steel tubing. I wouldn’t say it’s “perfect” 19.04-19.25mm. So let’s see, that’s 0.21mm out of round on the diameter, or 0.105mm on the radius.
4. I figured you might have 😉 Good to know. That does get me noodling on what materials might be good guy-wires and a good way to tension them. It would be *really* slick if I could use the same material for guy-wires and line-drive, e.g. spectra.
-
-
-
-
Hi Quentin, brain pickings again 🙂
Here’s a new idea for the frame and table:
Did you ever explore this corner-style format?
One more with 225mm arms and a 300mm build plate:
-
-
- You must be logged in to reply to this topic.
