No need to say sorry, I really appreciate the help!
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Recently I learned these touch probes can be had from AliExpress for like $60.
Chucking up in the collet is by far more trouble than it’s worth, but with the combination of easy removal and kinematic repeatability, it could open up possibilities.
At the current rate, I might get to it in the spring of next year.
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Cool! Are you thinking mesh leveling? Something else/more? I’ve been thinking mesh leveling for good while!
Are you talking about this kind of listing?
https://www.aliexpress.us/item/3256803280100804.html?spm=a2g0o.productlist.main.1.66cc70a2uRGrQG
Based on a video there, it seems to be probing laterally instead of vertically. ??
You are probably already aware of this and you’re simply envisioning something different than I was.
I think i saw them on amazon too
Yes, I am thinking vertical and lateral, unlike the BLTouch for example which only works vertically.
I made one a long time ago because I didn’t know you could buy them for a reasonable price. Assuming they were available then.
The software side is still missing a lot, for example probing the center of a circle or correcting for a skewed workpiece, although for hobbyists these are more niche uses, so it’s not really surprising they don’t get much interest.
Mapping an uneven workpiece should be doable with existing features and only requires vertical probing, so a probe like BLTouch would work for engraving on an uneven surface I would think. It is still advantageous to be removable and repeatable, so that use-case also benefits from the kinematic accessory attachment.
The probe combined with kinematic mount is perhaps a solution in search of a problem, but it is a cool solution.
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Something like this would have been awesome when I made this beach sign
Every time I moved it to do an epoxy pour I was nervous I wouldn’t get it back in the exact spot. Then once I cut the outside I totally lost it all. Was extremely nerve racking putting the groves in the back. So worried I wouldn’t get them centered correctly. Something like this to know exactly where the part was and where to set zero would have been AMAZING
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Could you do something like 3D printers in the pre-BLTouch era where the probe is installed with a known offset (X,Y,Z), and deployed for probing? Then stow the probe and get on with machining.
The old 3D printer setups used a servo deployment or even manually flipping the probe.
My solidoodle workbench had a microswitch based probe where the operator had to manually click the probe down, and then after the bed leveling cycle, it would run the probe/extruder assembly down to a point where the nozzle was at 0, and this forced the probe to click (pop) back up to its stowed position out of the way of the extruders. It was horrible to get working right and needed lots of tweaking, but for a few of us that stuck it out it worked reasonably well. You had to pay close attention to every print, because it had lots of weird failure modes.
That’s an example of a crappy system, but is notable because even manually deploying a probe is probably acceptable for the workflow for the V1 machines.
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Yes, this is exactly the idea. There will be a fixed X/Y offset between the router and the probe, and Z will remain constant until you switch bits. You can measure the Z offset with paper or something.
Deploying the probe is attaching magnetically and stowing is removing it. Convenience and repeatability are key, and I think those are both covered.
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How does the glue holds after all this time? Would it be wise idea to still add a screw?
And would it be an option to put the magnet too in the mobile base? What is your idea on that?
Yeah this is the cheapest on amazon. https://www.amazon.com/V5-Waterproof-Anti-roll-Compatible-Finder-NO/dp/B0BDSDSJF6/ref=mp_s_a_1_5?keywords=cnc+touch+probe&qid=1690330751&sr=8-5
Others go up to 90
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The glue on the washer is still holding strong and I think it will hold forever because it has a large area.
The problem with the magnets is that the front has a strong field and the back has almost no field. If magnets are oriented front-to-front they will repel, so that won’t work, and front-to-back is not much better than just using iron for the second piece. Flipping the magnet in one of the holders is possible but for me it didn’t seem worth it. The magnet to washer has just the right amount of force in my opinion.
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@jamiek is exactly right, and I concur. (And I mentioned those problems in my video.)
I had tried washers first, and the only reason I switched to magnet to magnet (flipping magnet on one side) was because my washers were non-ferrous (not subject to magnetism), and I only later found out that a certain type of stainless steel is non-ferrous, and often used in washers. For ordering washers online, the easiest way I have found for making sure they are subject to magnetism, is to buy ones that say “zinc coated”!
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Than you guys!
I will try to find the correct o-rings.
I’ll probably try to glue it with some epoxy so it has a strong hold.
I bit my tongue, as I’m not trusting what I’m about to share (and I’ve not done any testing either).
But I watched a YouTube video, that said doubling the number of magnets, depth wise, increased their holding strength. In other words, instead of two magnets, in position one, having 4, in position one. Two on each piece, one on top of the other.
In my mind it doesn’t work that way, and I’ve been meaning to test that theory for my own curiosity.
I think it was for a vacuum quick disconnect, made out of wood. Same overall design, as the 3D printed ones. But it could have been something RC related as well. Can’t remember.
Just thought either someone is going to be able to confirm that tuber is wrong, or it might be an option. Again, sounds not right to me…
Actually, in my experience it would greatly increase the holding strength to double up the magnets. I don’t know about “double” but I can agree to much increase.
Also, in my experience it increases the holding strength to increase the thickness of the amount (mass) of non-magnetic yet ferrous metal being mated to the magnets.
Thanks for that info Doug.
Sounds like the ferrous metal on one side is still stronger, but for those who have plenty of magnets and depth to work with….
The magnets I used, are strong enough when using one magnet and one washer, stronger with one magnet and two washers (double the washers not the magnet) and very very strong when using two magnets, but only when one of the two magnets is flipped.
Not all magnet products are equal in strength. It really matters which kind you get. Magnets have an “N” rating of their strength. Higher is better. Also, look for the word “neodymium” — stronger, better.
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It pretty much does work that way - someone posted quite a detailed explanation (might even be on this thread) about distances etc.
I designed my workshop dust collection fittings, probably along the lines of the wood ones you mentioned, so that I could add extra magnets from behind if they were necessary - they weren’t, but doubling them on both fittings had spectacularly noticeable effect.
Just another simple tip - if you are using magnets in an array like this, alternate polarity - all you need is a slight twist to get them apart and that when they come into range of the adjoining magnet they repel - if that description makes sense!
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