@franklyrosalind Any chance of a LR3 table generator?
@franklyrosalind Ok, question time…
For the flat rails - are the long and short ones supposed to meet at the center of an X rail or just out in space? If they don’t center on an X rail, I’ll have to add a doubler on the underside to make sure the joints are stiff.
Sorry, low-to-zero chance I amend it for an LR3. Too much work, and I have no way to really test (I am definitely not going to build a new table for a device I don’t have!)
I tried to make the code relatively well-structured. If you want to take a whack at it, I will review your PR 
They meet in space. I thought about meeting on a spar but it’s helpful to be able to move the rails forward and back to make sure the device is positioned correctly.
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Where would I start?
The code for the table generator is at GitHub - 3ach/table
Glued up and drying. Feels like it’s gonna be really flat and stiff.
A note on the layout of the “flat” and “tube” rails:
- The layout of those rails in the drawing is reversed-- the “flat” rail (with the extra width I gave it) should be “above” the “tube” rail because it’s going to end up on the left side of the table (as looking at it from Y0) and we want the longer rail to be closer to Y0*:
I can fix the issue by selecting the 4 objects in Inkscape and doing a "flip vertical on them and the layout matches what I would expect:
(unfortunately, I didn’t notice this until just now, so I’ll need to cut those out again. Yes, I know I could just turn the pieces I cut over and manually drill holes where I want them, but, you know, automation… 
)
*Having the long rails at the Y0 end of the table makes the most sense – most people will be working closer to Y0 all the time, so putting the joint in the rail closer to Ymax eliminates the issue of having to run the Y axis assemblies over that joint all the time.
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Firstly, I am so unbeliveably stoked to see someone use this thing I built to make a real thing. Thank you for your patience and feedback!!
The holes are meant to be through cuts, and the little notches for the position are on the ‘inside’ (hidden.) I don’t think you need to flip them. Or, rather, I have my table set up like yours (long top rails on Y0) and I didn’t have to.
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Ahh! That’s where I went wrong - I didn’t drill all the way through. That one is easy to rectify!
Feels like the generator could use a README - maybe I can put something together when I get done with building mine. Keep an eye out for a PR…
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More progress. Built a base from scrap lumber and got the table mounted. Flat rails drilled through and mounted one set of belt holders and verified they were the expected distance apart (and they were - the calculator works!)
Somehow, while re-orienting the SVG and setting it up in VCarve, I managed to “lose” the drill holes for the belt holder on the Xmax/Ymin side. Not a big deal, as they are just mounted flush to the end and outside of the flat rail.
I’ll have to cut new x rails for the LR4, as my previous table was sized for 48” and the new will be 49”. And then new strut plates will have to be cut. So it’s gonna be a while before I’m back up and running.
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Could you explain X Cut Dimension and Y Cut Dimension?
The biggest MDF board I can find is 1220x2440mm. The X and Y cut dimensions are larger then this.
Do you mean the pre-loaded ones? They just autoconvert from inches.
Yes, exactly! I have only changed the units from inch to mm. So I should enter 1220 and 2440 mm ?
yes, if that’s the size you want to be able to cut on the LR4, that’s what you should put in.
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Congratulations Zach, I love your table designer.
I think I got a few things wrong when I input my settings in a sleep-deprived haste . I mostly took the defaults but decided to extend the x by 1cm or so for some reason that I can’t remember.
It means that the skins are just overlapping the spars by only 6mm or so. They are glued and nailed so I dont think there will be a problem. There is a small chance it might even be a benefit as I can use the underhang to support a strip of thicker board to act as a stop to hold a full size 1220x2440 sheet in place.
I decided to make mine a vacuum torsion box and make the top skin a 18mm thick plenum that I will cut a pattern of channels . I have painted the inside and outside of the torsion box with gloss paint to seal it to help keep a vacuum.I have configured the inside into 4 zones that will be fed via x4 3d printed ball valves. I intend to to put foam strips around the 4 zones. The foam holding channels will be about 6mm deep, I had intended to use a 12mm top skin but was worried that the 12mm when channelled to 6mm deep might be vulnerable to too much the pressure/downward force when under partial vacuum. The bottom skin is 12mm. Probably all overkill, it feels like it weighs a tonne.
The purpose of this post is to say many, many thanks. 
I understand the rails correctly. The thinner of the rails is for the side of the gantry with a roller and a belt, it attaches to the side of the table with the shorter spars. The wider rail is for the side with a steel guide tube and it goes on the side with the longer spars?
Also I am assuming that the shallow engraved lines should line up with the centre of the appropriate spar?
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Wow, I would love to hear how the vacuum works out!! Workholding is the biggest weakness of this table so far in my shop – if it works for you, I may rebuild as a vacuum 
The shallow engraved line is supposed to be ~roughly where the edge of the last spar is. I wouldn’t measure exactly. Test with your own machine to find the right Y placement for (0,0) to be where you want.
So glad the tool has been useful for you!
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Yes, that’s right!
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DOHHH, where have I gone wrong?
I just laid everything out, luckily I only screwed one rail down without glueing (the other rail with the belt was still loose). I checked the carriage on the full Y range for free movement and noticed that the centre of the router bit over hung one end of the x side by a couple of inches, at the other end it is short of the 8x4 bed by a couple of inches. Everything seems shifted in the Y direction by a few inches.
When I attached the vertical side rails to the end of the spars with the shallow engraved line aligned against the outside (side closest to the nearest X side) of the penultimate spar.
Has anyone else experienced this?
BTW, Zach, I’m not sure, but I think there is a bug in the calculator. When I specify mm, I get a different layout for the corner holes than when I specify inches as the units. See screen grabs below…
BTW , cms are OK
I’m confused by your description. Could you maybe include a picture of your machine at roughly the minimum coordinate (for me that’s all the way to the front, all the way to the non-tube Y side) and with a bit touching the worktop? That’ll communicate a little better which way your setup is off.
My version of this table has the minimum coordinate slightly off the worktop because I made some bad assumptions in the V1 of the generator. I thought I’d corrected them, though (there’s more discussion on this thread).
As for the hole bug, thank you for raising it. I’ll take a look.
The hole bug was simple enough I could fix it from my phone. Done: Fix clip holes for mm · 3ach/table@3b85ed8 · GitHub, should be live in a few mins. Thank you for finding it!!