I like the first incarnation. I think the distance from the balls to the nozzle in the second incarnation will mean any tilt in the effector will be greatly magnified.by etfrench - Delta Machines
If the "engineer" has a degree it certainly isn't in mechanical engineering Using four points will over constrain the bed which is never a good thing. If you cannot get the plane of the bed parallel to the X and Y planes with a three point system then you either have a warped bed or don't understand how to adjust each point. Have you determined if your X and Y planes are parallel?by etfrench - General
I could use 3d printed sandpaperby etfrench - General
Lots of fluff, butby etfrench - General
Igus filament is rather expensive. I wonder if one of their regular bushings could be repurposed by heating under pressure?by etfrench - General
Delrin/Acetal nuts are pretty easy to make: You may also be able to find one on Aliexpress.by etfrench - General
Quotefrankvdh However, despite all this, there just doesn't seem to be enough force holding the balls to the magnets. A small protrusion on the top of the print (e.g. a bit of drool or over-extrusion) is enough to break one of the magnetic joints apart. Any thoughts on how to make this work? I've run out of ideas and I'm seriously thinking about going back to Traxxas rod-ends Add springs forby etfrench - Delta Machines
On a current project, I'm using machine screws and tapping MDF. After drilling the holes, I flood them with CA glue, then tap them (after the glue dries).by etfrench - Reprappers
Here's a design that doesn't require any heating and uses standard size PTFE tubing: The empty spaces between the ball and magnet could be filled with smaller sized PTFE tubing.by etfrench - Delta Machines
McMasters has conformable PTFE tape. A 5 yard role is enough to do 360 ends.by etfrench - Delta Machines
+-.5mm means you could have up to a millimeter difference in the distance between a pair of arms. That would definitely effect the accuracy of your prints. You may just need to make extra, then select the ones that match best.by etfrench - Delta Machines
Your magnets wont generate enough force to hold the arms with a 2mm gap. It may work if you use a punch to cut a round hole in the PTFE first. Keeping the socket perfectly centered is probably the biggest issue you'll face. When I tried it with ABS a few years ago, I wasn't able to keep the sockets centered well enough to use them on my delta. The sockets themselves were a perfect match for tby etfrench - Delta Machines
I doubt the effector and arms will be able to constrain the motors from rotating slightly around the ball screws.by etfrench - Delta Machines
+-1mm tolerance?? Is that a joke? You can hold better tolerances with a handsawby etfrench - General
If you already know your design is not very good, why proceed with it? p.s. Look at Momusby etfrench - General
Before you build it, I'd recommend posting your design on cnczone. You'll quickly find out how good the design isby etfrench - General
This should give you all the specs you need p.s. I built my CNC router for under $500 with most of that in the VFD and the spindle motor. I used 25mm unsupported rails for a usable build area 18"x15". The carriages were made by casting polyurethane around bushings. The frame is MDF with tensioning rods. The design is based on MicroCarve's work. I routinely do aluminum on it.by etfrench - General
It's a faulty design if you can crash at high speeds. I'd put a limit switch in before your carriage can hit the end of its travel. You can test the distance it needs in the middle of the travel instead of the end.by etfrench - General
How did you determine the amperage your board was producing?by etfrench - General
What's the downside of having the magnet touch the ball as long as there is no pressure involved?by etfrench - Delta Machines
Use a good renderer in your 3d model program like they did Acetone vapor treatment works for ABS but not PLA. PLA sands better than ABS. High fill paints work well for smoothing prints.by etfrench - General
No, it's not the same. This tape has adhesive on the back.by etfrench - Delta Machines
QuoteRoger123D your best bet is to contact the supplier by email with what you are using it for and they will set that or advise you. With linear bearings it is best not to remove the block from the rails Blocks are quite easy to safely remove from the rails for cleaning and replacing balls. You just need to remove the rails from blocks, not the blocks from the rails.by etfrench - Reprappers
PTFE tape is available from McMaster Carr as thin as .0035". I'm using the conformable version that is .0045" thick and haven't seen any wear in a year or so of use.by etfrench - Delta Machines
Or you could just use a program like Gearotic to create your pulleys and/or verify your results: GT2-2mm 20 teeth: Outside Diameter: 12.2244 Pitch Radius: 6.3662 Root Radius: 4.1122by etfrench - General
Normally, when you design something you base it relative to known dimensions. In the case of GT2 pulleys, the known dimensions are the root diameter and the diametrical pitch. If you need to allow for different thickness belts, then the part securing the outside of the belt should be adjustable. The thickness of the belt should not affect how it tracks.by etfrench - General
Did you read the specs in the links I provided? They have all of the data needed to make your calculations. p.s. Gates belts are not that expensive.by etfrench - General