I Gotta Have More Triangles
I've decided to print the corners for the printer myself. On the first go round, I'm going to use ordinary PLA and print the best set of corner brackets I can find for a delta printer made of 1 inch T-slot. So far I like bruckj's design. Its simple and functional.
But, it might not fit within the build volume of my Up! Plus2, so I'll probably have to modify the design slightly.
Once I get the printer to an operational state, I'll be able to print much larger parts than I can currently. What I would like to do eventually is design and print new brackets with some big ornate clawed feet and stuff like that.
The big concern about using printed brackets vs metal ones is whether they will get loose and wobbly after a while. I have some thoughts on that though. The problems people are having aren't caused by the softness of the corner brackets, they're due to a design that doesn't have enough triangles.
If you look at the earliest delta designs, you'll notice the frame consists of three rectangular sides, a triangle at the bottom, one at the bed level, and one at the top. We all know that triangles are much, much stronger than rectangles. A delta is more stable than a four sided printer of similar design would be. But, the design is still flawed, because the sides are just rectangles so the entire structure can very easily twist.
I think that's why people have problems, not because their corners aren't stiff enough or the metal rods are flexing. If you look at the big delta printers that people are having good success with nowadays, most of them have some kind of cross members to create triangles out of the sides.
Thats my theory anyway. Time to put it to the test...
What I'm thinking I'll probably do for starters is just get something like this slotted flat strip and use that to make cross bracing.
But, it might not fit within the build volume of my Up! Plus2, so I'll probably have to modify the design slightly.
Once I get the printer to an operational state, I'll be able to print much larger parts than I can currently. What I would like to do eventually is design and print new brackets with some big ornate clawed feet and stuff like that.
The big concern about using printed brackets vs metal ones is whether they will get loose and wobbly after a while. I have some thoughts on that though. The problems people are having aren't caused by the softness of the corner brackets, they're due to a design that doesn't have enough triangles.
If you look at the earliest delta designs, you'll notice the frame consists of three rectangular sides, a triangle at the bottom, one at the bed level, and one at the top. We all know that triangles are much, much stronger than rectangles. A delta is more stable than a four sided printer of similar design would be. But, the design is still flawed, because the sides are just rectangles so the entire structure can very easily twist.
I think that's why people have problems, not because their corners aren't stiff enough or the metal rods are flexing. If you look at the big delta printers that people are having good success with nowadays, most of them have some kind of cross members to create triangles out of the sides.
Like this Delta Wasp for example.
Thats my theory anyway. Time to put it to the test...
What I'm thinking I'll probably do for starters is just get something like this slotted flat strip and use that to make cross bracing.
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