Pictures PLEASE!!! I really want to see this work of art!
remember, the original frame was 2x4s weak side forward, so a 2x3 strong side forward is going to be stronger.
These are images of the design I was working a few hundred posts back. You can see how the CoG at 10 degrees could be worrisome. 15 degrees is much more comfortable… hopefully comfortable enough. The pivot point is the back edge of the front leg. The motor and top beam is behind the pivot point at 15 degrees but not at 10 degrees. We should check this on the actual design, though.
Most of the scientific comunity in the us has switched to metric, i believe it was after a space probe whnt the wrong way because one module was made with imperial sizes, and one with metric.
That said, that only points to a problem if you use both units together.
A lot of it was metric when I worked there in the early 70s. I’d guess it was a mixed up RFQ thing combined with contractors that didn’t read them carefully enough, or maybe just one programmer’s SNAFU. If it was as simple as one metric and one inch module it would have been caught in ground testing.
I was a Univac mainframe systems programmer, it wasn’t me…
Are there comprehensive instructions of the new frame build?
It’s still a work in progress as things are tweaked.
posted as message 680 in this thread
You are only using one board on the top beam right?
Yes, the top beam is either a 2x4 or a length of unistrut
The critical thing is keeping the motors at a consistant distance from each
other, so the critical force is down the length of the beam.
Is there a material and cut list?
Also thank for the quick responses. Cheers
the most recent version of the cut list is posted in post 694 (color coded to match what we are doing in the assembly instructions)
note that the top two boards on the cut list image are only used if you add some of the optional things
I’ve been quiet, but following along. I took apart my frame made with bolts today and re-constructed it using screws. I still think the bolt technique has some advantages, but I like the screw and glue technique as well.
I think there is some room to reduce the complexity of the design significantly, but I like that a lot of the complexity seems to be in optional steps.
My biggest concern is that right now the design is using an angle bracket, is that correct? There is not time to add that bracket to the upcoming batch which will be an issue.
I’ve been quiet, but following along. I took apart my frame made with bolts
today and re-constructed it using screws. I still think the bolt technique has
some advantages, but I like the screw and glue technique as well.
I think there is some room to reduce the complexity of the design
significantly, but I like that a lot of the complexity seems to be in optional
what do you want to drop?
I’m thinking that the instructions to make it folding, and the foot improvement
should go to separate documents
the top beam support is the hardest one to deal with.
The other complex step is the top crossmember, if we shorten the diagonals
(which we would need to do to tilt it back more), we can simplify step 5
what angle do you want the machine to be at?
My biggest concern is that right now the design is using an angle bracket, is
that correct? There is not time to add that bracket to the upcoming batch
which will be an issue.
That was an attempt to simplify and error proof the top beam mounting, we can
still use the 2x4 or stacked/bolted blocks.
I think that if the top beam is flat as opposed to standing up there should be no problem with the assembler screwing it down. I think that without a drill press or a portable drill guide it would be difficult to get a bolt straight through 7" of 2x without coming out the side.
note that it’s only needing to go through 3.5" of 2x4, not 7" (lag bolt through one board into the other), so it’s not quite that bad, but I agree laying it flat makes it easy.
extending the kicker to 30" makes it hit the ground right about 15 degrees. any steeper than that and we need to move the bottom of the work area higher or not have the legs symmetrical (which I think significantly complicates the build)
I haven’t checked that the legs still work at that angle. I’ll do that later tonight.
Please let me know if I should just leave it at 10 degrees and not fight it