Awesome! That book must be a fun read.
Because you asked…
The base plate, the top plate, and the wheels were made using the lowrider. Because the power distribution takes up so much space, I plan to create another level, maybe out of 1/4-inch or thinner stock, that sits between these two plates and move all the power parts to that. Less likely someone will touch something they shouldn’t.
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The pulley grab screws will slip more the closer you get the bit to the loose screw mind always do anyways
You can load estcam on multiple comps just 1 user though
That is awesome. Is it running ROS? I see a pi on there, but I am not sure you can run ROS on a pi. It would be fun to build up some SLAM using that connect. Does it have any localization sensors? Specifically, wheel encoders, gyro or accelerometer?
That looks like a bunch of fun.
I made a new thread for it…
Back on subject, I discovered my wooden blocks that the belt holders are attached to are just press-fit inside my unistrut rails. I forgot to insert screws in them to keep them from moving… which explains why my belts tend to loosen. I need to reset the blocks and all and secure them. I’m not sure if that explains the wandering or not though. When I cut the wheels for the robot above, I noticed issues with having a stepped cut again (I think it was the top right quadrant of the wheel).
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More ‘wandering’ issues AND some broken bits… Last night I cut new parts for V2 of the robot and broke three 1/8-inch bits. I had set my DOC to 5 mm and my feed rate was 480 mm/s (8 mm/min). I used 5-degree ramps for everything and all my ‘small’ holes came out fine. But when I went to cut out a large shape, a bit snapped. No problem, replaced the bit and modified the gcode to restart from the piece that was being cut.
Then I went on to another piece that was a couple of feet further down the x-axis. I broken two bits on that one. Both were on “large” pieces (10x2-inch hole and a 20-inch circle). Its VERY possible the bits broke because the board was slightly ‘bowed’ and I didn’t have it perfectly flat, and therefore it might have been cutting more than 5 mm on the first pass, but I hadn’t broken any bits before and this time I broke three. The last bit break was due to the wandering issue (below) where on the 20-inch circle, the bit wandered and definitely was trying to cut more than 5mm.
But, the real issue is that I experienced wandering again. Among having problems with the 20-inch circle, I noticed this with a 10x2-inch hole…
The top image is the dimensions of the hole and how the cut was performed on 1/2-inch plywood from HD. The bottom image shows the step that was formed as I can feel a little step on both sides of the cut… It’s not a precise depiction of the step, just made it based upon how it felt. The ends (where in the X-axis was steady) came out fine, but there the X-axis moved, there was a step. What I find odd is that both the top and bottom had steps. The question I have is why steps on both sides, and why at the bottom of the cut? Seems to point to Y-axis issue to me, but it just seems odd .
I don’t know that I have any answers for you, but I’m wondering what kind of bit? Or maybe something’s wrong with the collet or the router itself. I’ve only broken one bit. I didn’t get the collet tight enough, and the bit eventually slipped down. This wore down the collet as well. Even then the bit didn’t break right away. I tightened it back up and kept going, but eventually the bit broke and chewed up the collet further. I replaced the collet and have had no issues since.
I just finished a project cutting parts that are 24" square or so with an 1/8" 2 flute up-cut spiral bit from Ryan, with no issues. I had very similar cut settings (5.1mm DOC, 540mm/min).
I was probably using similar plywood too, ~3/4" BC HD plywood. This also had some significant warpage, that I could not pull out. I’m pretty sure I was cutting at least 9mm deep on the first pass in that area. My Lowrider just plowed right through.
They are cheap and I’m not so worried I broke them. My concern is mostly with the step and I had similar issues using nice quality 1/4-inch bits…
https://www.amazon.com/gp/product/B074R9VXKQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
What I am thinking of doing is buying some 1/2-inch foam board and doing some cuts in it. If it comes out clean, then the problem is something ‘dynamic’ from the load of the cut. If it’s still stepping, then there’s some kind of alignment/structural issue causing it. At least that’s the theory.
Also, my Y-plate on the side with the controller ‘droops’ down some (think I mentioned this in another thread). When the z-axis is low, It’s really apparent that the wheels are tilted outward. I recalled this morning that when I was assembling the parts, the holes for the wheel bolts on the Y-plates were not perfect circles, but rather had some oval-ness to them. I didn’t get concerned at the time but I’m thinking maybe I should use my lowrider to cut some replacements… would allow me to make some tweaks to it to facilitate mounting the controller better.
You’re either going too deep or too fast.
Either reduce DOC or reduce feed.
The wandering bit could be due to the bit grabbing the wood and following the grain.
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So my test in foam should come out clean if it’s related to this, correct?
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correct.
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I think the foam cuts are a good idea.
Also, FWIW, the bit I’ve been using is like these, from the same seller you linked.
I’m trying to understand about the wheels tilting. The bolts through the YZ Roller assemblies should be holding them perpendicular to the Y Plate and Z tubes. Seems to me like something isn’t right, and would be worth trying to figure out
You say 480 mm/s and 8mm/min. That is not right correct if its 480mm/s it’s way to fast
Unfortunately I had a disaster today and my x axis belt on the side next to my shed wall came loose… I think one of the little black inserts popped out (can’t find it), loosening the belt near one end and then when trying to makeshift a solution, the one on the other end popped out. So, I now need to find a good solution to belt termination… I’ve had a lot of problems with the belt coming loose. Hopefully something not complicated or require 3d printing.
The zaxis tubes seem straight, but both the wheels tilt outward (positive camber). They seem straight on the other side. All I have weight-wise on the Y-plate the RPI, mini-Rambo, and the LCD screen… none of which seem very heavy.
Maybe more zip ties? You don’t need them to be supremely tight. Jist enough that they stay taught.
I haven’t had that particular issue with the Z. I remember an issue where that was assembled backward, and one of the piece had a flange that was making it crooked. The V1 didn’t have a flange (and I haven’t upgraded yet…), so I’m not sure.
I had put extra zip ties on it to keep that bugger in place (had popped out before). Maybe I’m doing it wrong… but now the piece is missing and I’m looking at different options.
As for the ‘flange’, I had noticed what you are talking about when I first assembled and undid one setup because of had it wrong… I assume I got it right.
I’m mostly really impressed with @vicious1’s designs, but I don’t like those little belt inserts. It just seems like a bit of a kluge, and they’re really fiddly to put together. I found them frustrating (and as an aircraft mechanic, I’ve made a career of assembling fiddly bits by feel while reaching through a 4" inspection hole in wings and such}. I think there is a more elegant solution.
However, I’m wondering if your belts might be a touch loose. Once those fiddly little inserts are in place, and the belts are tension-ed, they should be pretty well trapped, and unable to pop out.
Regarding the tilting wheels, I don’t think the weight is an issue. Looking at my Lowrider to see how the wheels could be tilting like that, has me thinking the lower Z rollers might be installed with the wrong side towards the plate. I would think that tilt would be binding up the Z axis a bit too. I don’t see how else it could be tilting like that.
You mentioned possibly making new Y plates, as well. I don’t think a little oval-ness in the wheel holes is likely to be an issue, but I think I’ve seen a couple of posts about 1/2" MDF “sagging”.
When I first assembled my Lowrider, I made my flat parts (611 plate and Y plate) by hand on a bandsaw, out of scrap and they were a touch rough. As soon as I had it running decently, I used it to make some good ones out of Baltic Birch ply. Baltic Birch is pricey, but it’s really nice for stuff like this.
Hope you get things worked out, I’m watching your robot project with interest, and looking forward to more progress.
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