Piezo20 probe and piezo kit now available
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So this would be a piezo with a hole for a bowden, and you just drop it over the top of your groovemount (around the bowden)?
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So the idea is this is a module which will sit between the groovemount in your effector/carriage/extruder such as a titan, and your hotend. It will have just a 3 wire endstop connector on it. Its pretuned and tested on my rig. If you are using one in a chamber or your ambient temp is 35 deg C+ then let us know we will tune one for higher temp environment, or leave the PCB adjuster with no threadlock on it so you can tune it yourself.
If using bowden, you'd just feed your bowden tube through the middle, there will be space to attach and tension the bowden tube on the hot end, as well as remove the hot end without dismantling the module. If using direct I will supply a short length of bowden tube to use as a filament guide from extruder down into the hotend.
This is what it looks like in my test rig. If you don't want groovemount I'll do a version with captive nuts and bolt holes for direct mounting to underside of a carriage or effector. Almost no compliance of the nozzle in this design, the piezo is pre-tensioned quite firmly.
The new custom PCB will be attached to the back of the module for the transparent version and it will light up the module when powered and hopefully change colour when triggered. If preferred a solid colour version will also be available with the pcb on the front (you can insert the module into your printer whichever way around you want) so it will show two LED's one for power, one for triggered.
This module completed 2000 probes on the rig with no issues. I intend to do a test run of 36800 probes which will simulate a full year's use in a heavy-duty-cycle environment, based on doing 16 probes on a delta to autocalibrate each print, and doing 10 prints per day for 46 weeks per year, 5 days a week. This is likely to represent 3+ years of use in a slightly more normal environment.
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DJ think there is a typo and you mean 5 days a week and not 5 days a year
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LOL fair enough edited. Also that didn't multiply up to 38000, it was 36800 probes (edited), I was doing that from memory. Its done 2000 already so another 34800 to do, surprisingly it only takes around 30 minutes to do 1000 probes. I'd leave it going all day whilst I'm at work but if the module fails I am not sure how the rig will deal with it, so I need to do them whilst I'm around and about.
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This is what it looks like in my test rig. If you don't want groovemount I'll do a version with captive nuts and bolt holes for direct mounting to underside of a carriage or effector. Almost no compliance of the nozzle in this design, the piezo is pre-tensioned quite firmly.
I'd be interested in a non groovemount one, I've been playing around with one of Moriquendi's boards on my reach 3d. Although it is groovemount, it mounts sideways onto a plate, so I reckon it is a good candidate for removing the grovemount. I'd just need to design some sort of interface to the captive nuts and my side plate.
My current setup is a bit bodged together (plate between the groovemount adapters, it does sort of work, but not as well as I'd like.
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This sounds really cool, but almost one of those "if you ask how to make it work, you probably can't figure it out" type of things. I am quite interested in trying one of these sensors. While I do like the IR sensor a lot, it would be very nice to be able to use on any type of surface. Is it possible to mount this on a cartesian printer? My printer is quite small so if the hotend gets offset much, it will likely cause a loss of print area available.
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Jmg123,
No problem whilst I haven't made a screw mounted one yet its not a problem. Please give me a shout in a week or two when we're ready to start sending some out and I'll make you one.
Just a question it might be the angle of the photo but what do you do with the inductive/capacitative sensor on its side? Or is it just stowed out of the way for now?
ScotY
Yes its possible to use it on any type of printer. The module sits below the carriage/effector and the hot end clamps into it.
Please let me know once they are released if you want one. I will post something here, and on reprap forum we will have a support/order thread. -
And the module completed its 36800 probes without any issues, simulating a year of heavy duty cycle or three years of "normal" use.
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I've been lurking around here for a while now.
I'm with Moriquendi on lifting the nozzle close to the plane of the effector. So I took DjDemonDs 20mm piezo design and made an effector to use with Haydn's magnetic arms. Arm spacing is 64mm, goes with a 30mm fan and a Berd-Air like cooling pipe.
The M3x25 bolts have no thread for the first 6mm at the base and that can make a good sliding zone. There is room for up to 5 but I think 3 will do.
A second Bowden ( http://e3d-online.com/Mechanical/Bowden/Embedded-Bowden-Couplings-For-Plastic-1.75mm-Filament ) can be used to stop the PTFE tube from pulling sideways.
I'm thinking to use it on the Kossel I'm building but that will take a while. Until then here is the link for .stl , .step and .f3d files.
https://mega.nz/#F!z40QRazQ!5OobZxS4iGTfcdOhj_lC3w
If you need them in any other format or modified in any way please askUpdated 22/04/2017 - Added a second Bowden and made some cosmetic modifications
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ScotY
Yes its possible to use it on any type of printer. The module sits below the carriage/effector and the hot end clamps into it.
Please let me know once they are released if you want one. I will post something here, and on reprap forum we will have a support/order thread.Thanks for the reply. I will definately get one if I can figure out how to mount it. I'm using an E3D Bowden setup. The mount for the E3D is the clamp type and then the mount screws to the x-carriage on the backside. I am assuming a custom mount will be required.
Actually, my setup looks a little like jmg123's setup above. The back of the clamp mounts to the carriage. Then the front clamp goes on, then fan, etc.
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AD-1 that looks great. I've been meaning to try a raised hotend version like that but have been too busy. Let me know how it works out and if you have any issues tuning it.
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Presuming a drilled 20mm piezo works just as good as the 27mm one, it should be easy to tune following your instructions
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Yeah I've not had any issues with 20mm in fact the unit I am going to be selling as a complete drop in module uses 20mm discs. Its Idris' (and Mike's) circuitry that does the job so well, reacting to change in voltage means even very small (but rapid) rises generate useful triggers.
It begs the question how small can we go? The smaller the piezo, the easier it is to incorporate it into any load bearing part of the printer which is compressed on nozzle contact.
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Awesome thread going on here!
Are you guys aware of this board?
http://wiki.seeedstudio.com/wiki/Grove-_Piezo_Vibration_Sensor
Will test it once I get hold of 20mm discs (and could this be an alternative for Moriquendi's board?) -
That seed studio piezo looks like it might be easier to incorporate into the more rectangular hotentd mounting form factors you get in Cartesian and corexy printers.
Also have you considered two of the smallest possible piezos one on either side of the hotend so you don't have to drill a hole through the center of a piezo?
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I was not aware of the grove unit linked to above but it is worth looking into. That being said we are on the border of using these things as load cells detecting dimension change, and microphones listening for the contact.
Very small piezo's might be the answer to many of the harder to integrate setups.
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I've been lurking around here for a while now.
I'm with Moriquendi on lifting the nozzle close to the plane of the effector. So I took DjDemonDs 20mm piezo design and made an effector to use with Haydn's magnetic arms. Arm spacing is 64mm, goes with a 30mm fan and a Berd-Air like cooling pipe.Here's what I came up with for a delta effector that integrated the piezo elements. There's no need for a drilled piezo or having the leverage of the length of the hot end hanging off it.
Those are 15mm piezos with a brass nut soldered to the back.
Idris
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The picture above got me thinking that maybe I could use piezos on my latest Diamond hot end mount design. I'm planning on using the nozzle as a probe and had intended to use some sort of switch but now you've got me thinking. Sorry but I don't know how to post pictures directly but here is a shareable link to an OpenScad png of what I have. https://drive.google.com/file/d/0B_MwtHtQR_ZvOTJxVklrWGdlN3M/view?usp=sharing
The red part is the X carriage upper section. Ignore the pale blue part which is the X carriage lower section, but the white part is the Diamond hot end assembly complete with heat sinks, fan and shroud with short tube sticking out to represent the Bowden tubes. There are 3 bosses on the x carriage which will have bronze pushes inserted and there are 3 mating bosses on the hot end assembly which will have steel dowel pin inserted (shown in grey). So effectively, the hot end will just drop in but can slide in Z. It weighs 250gms so I'm hoping it'll stay put without any form of retainer but the Bowden tubes will also be under compression so will act as springs to some extent.
So the question I have for you guys is, could I use one or more peizo discs between the bosses on the carriage and the bosses on the hot end assembly? Would it work with just the weight of the hot end? Should I put peizos on all 3 bosses? Any other thoughts?
Thanks
Ian -
deckingman… I think Idris 3 piezo design could work for you.
Idris... I like your idea better. Lightweight effector and no moving/sliding parts. I went the other way to avoid soldering piezos, something I'm not that good at.
How do you solder to last? And they are connected in parallel I presume? -
They are connected in parallel.
Preparation and stress relief is the key to soldering piezos easily and to last. My process goes like this.
For the electrical connections:
Thoroughly clean the piezo with acetone or alcohol
Tin both wires
Tin the brass ring of the piezo
Tin the centre contact (put the solder wire on the contact the the soldering iron (at 360deg) on top of the solder, as soon as the solder melts, remove the iron.
Solder the wires to the piezo, tinned wire on tinned contact, touch momentarily with the iron and you're done.The trick to getting the connection to last is to fix the wires somewhere close to the piezo, the solder joint will pull off with very little force so you need to make sure any force on the wires is taken up before it reaches the piezo.
To solder the nut to the back I'm using solder paste but you could do the same thing by tinning the nut, cleanliness is key, I sand the nut and the piezo with very fine sandpaper before soldering then use a very hot iron on top of the nut to reduce the thermal stress on the piezo ceramic.
Idris
