As long as it ridged enough for 4 foot that is great
I took moved my daughter’s bed the other day. Those cheap bed frames are made of strong angle iron. My brain started wondering if I could use an old bed frame to make a large format CNC. Silly things my brain does. I am not suggesting this as an idea. Just thought it was funny.
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I tries to give a bed frame like that away on CL. No takers. They will give them to you when you buy a matress at some matress stores.
What free CNC frames 
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How about hockey pucks for the wheels, just add a center hole and you are done, they are ~$1 each, compared to the $4 in the ship. Might help with a guiding rail system, flat to flat at a lower distance than rounded wheels.
Cheers!
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I think an “upgrade” would be switching exclusively to metric fasteners. Sure, you wouldn’t be able to pick them up at Walmart, but every town in the US/Canada has a Fastenal, and McMaster-Carr ships everywhere. Even better, a good reason to order directly from @vicious1.
I understand people think that makes it easier, because “90%” of the world uses them…but 99% of my paying customers are in the US. I will do my best to make sure metric works, always have even before you could buy a single thing from me. I am located int the US and buy bulk hardware in the US, Metric is significantly more expensive. So If I make it all metric only, I instantly raise my costs which passes along to the customers that choose to support me.
I made a machine from day 1 that supported metric and imperial fasteners. This gets brought up so often you would think I made it not support metric, it always, always has. I chose #6 machine screws so M3.5 would work, The whole system is based off M8 bolts that fit the bearings perfectly, in the US we use a substandard fitting 5/16".
Number one complaint. M3.5 are non standard, too hard to get. Odd, I can get those in all the same places that carry metric fasteners in the US. Nothing I can do will be perfect, people will always complain on such a giant project.
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I am with you, I just placed an order on Amazon for some metric bolts, I may have bought out the local supply. Definitely easier to get Imperial, but I like eversweet margarine best.
In a perfect world… 
Cheers!
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Yeah, my point wasn’t so much to convert to metric fasteners (though I would support that) but rather that the design would benefit from embracing one system or the other. Currently accommodating both has its downsides.
Metric fasteners cost just as much up here (Fastenal and McMaster are both US companies, and they don’t charge us less); yet I built mine with them because as a fraction of the overall cost, the fasteners weren’t a huge amount. In fact the real penalty was having to buy 25 or 50 fasteners when I only needed 4.
I assume imperial fasteners are just as available in Europe are metric are here, but similarly at 3 times the cost.
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Thought of you guys when I read this
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Table saw fence attachment for the lowrider?
I think building a vertical lowrider is a challenge, but totally doable. Actually I would have done it already if I had any available wall space left in my shop, I considered it then had to face the ugly truth that it was not reasonable.
The way I’d do it would be to use the wall itself as the bed, since it’s made of concrete, then just attach a spoil board to it. So basically everything would be solidly bolted to the wall.
I would build it in “portrait” mode, so the longest side of the board was placed vertically, to minimize the occupied wall space. That also allows for almost unlimited height, the ceiling being the limit, this way you can park the gantry very high so it’ won’t be in the way when you don’t use it, freeing some space to put some table or whatnot under it. Then when you need the CNC you just move the table and you’re good to go.
So the X axis would be the vertical one, then Y axis would be left/right and Z towards the user.
The only real challenge in my opinion is to determine how to move the X axis. For that there are lots of available options, either a belt/pulley system with counterweights, a cable system similar to the garage doors, a rack and pinion system (using a large belt) with a beefy stepper and planetary reduction, a very long leadscrew… Each have pros and cons.
Right now If if had to chose I’d go with belt/counterweigt setup, either in a rack and pinion form or just the regular way. It’s probably the best ratio easy to build/cost/travel speed/accuracy. The threaded rod is easier to build, but it will move slow and is likely to wobble a lot.
The Z axis would need to be an entirely different system as the current one on the lowrider, so that only the tool moves and not the whole gantry. I’d make the gantry using 3 tubes, in order to better support the weight of the tool, so two tubes would be parallel to the wall and one tube perpendicular.
Really wish I had more space, that thing would have been really useful in my shop to cut panels and I have lots of ideas on how to build it… Maybe one day.
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8’ is a standard ceiling here. that means 100% vertical in portrait would leave you no room for the tool or router. On top of that setting a zero on the floor on your hands and knees is not ideal. A tilt would probably be best, but I am not convinced this is the right approach. Work holding becomes extremely important at an angle.
I think most people cutting giant pieces out still need a table to assemble them on. So a flat setup is much simpler and can double as a work table. If anything a tilt provides a place to store material. I screwed up and need to rework my shop a bit. One full sheet of plywood is really getting in my way, I have no where to put it so I just keep moving it around until I get a chance to use it. A tilt or table could also double as a panel saw.
Tilt could be worth it, if I was to do anything to the LR right now I would do a minor update to decrease the unique part count. It is such a hassle to package I might need to raise the price a bit as is. After that think about a full rework.
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Or how about just wheels (appliance casters?) that go on the inside of the end pieces to prevent binding and help with consistency, they are a buck or two each for 1 1/4 " here. Again not sure if that is a minor mod vs platform design.
Cheers!
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That is a redesign. A side wheel is only needed if you do not start your machine squarely, or is help to starting squarely. I would rather make dual endstops the norm before adding more hardware. They accomplish the same thing.
The other option is an asymmetric build with one captured side and the other floating.
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Are they binding because the rails are not straight or because the gantry is not square?
Is there ‘harm’ done if you run your lowrider into hard stops and the steppers chatter a second or two? Does it damage motors or the belts?
I am not opposed to asymmetric. If you leave a mm or two on each side and engage the motors it works fine as it is, if you leave the motors off and go to the start of the workpiece by (slowly) moving it by hand you can push one side more than the other imperceptibly. If you could roll along one side even it would help with runs that are against an edge vs cutting the center out of something. Same reason you would use a guide rail for anything. Thinking of the 8 foot boards I used for my table, the dido like pockets were not precise enough along the entire length, a free mm off, but enough to make a flush join a matter of chisel and sandpaper vs Ikea wannabe. If you want an 7’ Grove in some wood precisely 19.5 mm from the edge, I think it can be done, but the 10th pass it may be off. Hope that explains better where the suggestion is coming from, that and I saw some at the store and bought a few to see if they would even fit.
Dual endstops are a bonus, I may do dual Z as it is as that seems the more troublesome. Nice to have brakes for crazy gcode, but if you standardize dual you may as well go triametic (sp?) drivers, imo. Homing doesn’t seem to come up in that manner for me.
Cheers!
No. There are a lot of impact forces (like little hammer taps) which could be stressing the parts. But the motor and belts aren’t skipping teeth, they are just flipping between magnetic steps.
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