Loading

MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.

Download Now

ElmoC

Delta Effector for Nimble, Precision Piezo Probe, and built in fan shroud

by ElmoC Jun 4, 2017
Download All Files

Thing Apps Enabled

Please Login to Comment

A couple of small issues came up in playing with this and the Azteeg X5 mini that cascaded into major failures.

But first, how many steps/mm are you seeing with the Nimble assuming you have 32 microstep drivers and does the inversion of the Nimble change the sign of the actions (extrude and retract are now opposite)? In the short amount of time things were working, it seemed like retract commands were causing extrude actions. My extruder stepper was wired the same as my other 3 steppers, and all of them are doing 128 microsteps so I have to scale up by a factor of 4 and the nimble is geared 30:1

The hotend fan was not running which caused filament to melt higher in the body of the V6 causing it to plug. Trying to remove the V6 to work on it, I found that the heater block had welded itself to the bottom of the little shelf that makes up the bottom of the hotend fan mount. So I couldn't unscrew the heatsink as there is no way to go up and I couldn't unscrew the heater block as it was attached to the effector. Let's just say trying to break loose the heater block didn't go especially well for that hotend. I've trimmed down enough of that shelf so I could mount a second V6 with just enough space to see some light. It just didn't strike me, while assembling with that first V6, I was putting a heater block on plastic because everything was cold - I was more concerned that it was going to affect the piezo operation.

BTW: the panel opening is too wide for the 12 pin Molex connector so the wings don't clip in (I've made an embarassing hack to get this connector to stay in place. I pushed the connector up through the hole with the wings still below the surface and under the part of the wings that partially comes above the surface are very small holes - big enough to poke safety pins across under each wing thus keeping the connector from being pushed down and the ends of the wings keep it from coming up. Nice snug fit.)

The worst part of the disaster was self induced. Amid all the rats nest of loose wires and power supplies on the bench, turning the Delta frame a bit to get a better angle for reattaching the effector caused too much stress on the X5's micro USB connector leaving me with minimal Ethernet connectivity and a micro SD card to pass configuration back and forth to the X5. Still trying to sort out my best course of action to fix this - the first step is to walk away before I do any more damage today.

I am running 2600 steps/mm. I believe the Duet runs at 16 micro steps. For the extruder, I have it running the opposite direction as the axis motors. I don't remember if that was changed from my previous extruder and I can't recall if I had to switch it around after flipping the Nimble over.

Here is a picture of how my heat block is orientated. Once the hot end has been inserted, you cannot turn around without it hitting part of the effector. The position I have it in has the heat block the furthest away from all parts of the effector (looks like it rotated some when tightening). The part of the block with the heating cartridge goes to the back of the effector (opposite side of the fan).

https://www.dropbox.com/s/d4p0l54gc1vbeq5/2017-07-03%2013.08.23.jpg?dl=0

For the molex connector, if you used the same parts, it should fit. Both parts are similar in size, but not the same. The part with the shroud around the pins is the one that is suppose to go into the mount on the effector. If that is the part you placed there, then it could be a difference in the printer's tolerance. I used the exact size from the the Molex part documentation, without make any adjustments for the printer, and they have always fit fine.

https://www.dropbox.com/s/4oheqmd0qlfttyf/2017-07-03%2013.15.01.jpg?dl=0

Can't really help you with that last bit. :)

I am way short with my tuning of steps/mm then and I do believe that inverting the Nimble changes the sign of the actions.

My heater block is pointing at the E3D fan the same as your's. Not sure why my heater block was close enough to melt and weld the block to the bottom of the E3D fan mount and your's doesn't. The only variables I can see is the assembly of the E3D block to the heatsink being shorter on mine or something different in the Piezo-20's size or assembly (both I had assembled by the manufacturers).

You are of course right, the shell holding the male pins is 2+mm wider in both the X and Y directions. And how stupid that I didn't think to test fit both the male and female shells before soldering all my pins. I've made my mistake, now I'll have to live with it (although my mount may be easier to disassemble than squeezing a Molex connector to get it out of the hole of a printed part)

The new board is on the way and I'll try to put a new connector on the old one to use in a different printer. Worst case, I make a micro SD image all tuned up to stick in the old one.

One other thing that came to mind about the position of the heater block. Might you have gotten an older model? I'm not sure if I had published it, but the opening on the bottom used to be a lot smaller.

For the steps/mm on extrusion, probably the best thing to do is just measure it. Disconnect the nimble (bolt one size together so it doesn't fall apart), feed some filament in so the end is level with the housing, and then extrude 100mm (need to enable cold extrusion). Measure the exact amount extruded and use the formula:

(amount requested / actual amount fed) * current steps/mm = new steps/mm.

Do this a few times and you will get it.

(If you were already aware of this procedure, just ignore the post)

OK, I just got through my first full "tighten everything down" assembly and I have a few notes:

1) Don't assemble anything based on the photographs of the blue prototype - most everything is opposite from the black effector pictures
2) The hardware used to connect the Nimble to the mount is not from Nimble. Nimble's long bolts are not threaded to the top which is needed for the spacing nuts shown in the picture. Best to buy a couple of M3x40mm or longer from McMaster Carr that are fully threaded so you can put nuts above the Nimble to shorten the effective bolt as needed. I used a 35mm that I had on hand for one and 3 washers on the top of one of Nimble's 40mm bolts for the other (it's a tight fit as the OD of the washers are against the drive cable mount).
3) Watch out which end of the Nimble points up. If it's upside down, the filament release would have to open into the fan/wiring shroud instead of where you can get at it when needed. (took me a while to figure this out as I followed Nimble's assembly instructions to the letter which is backwards from what you need in this effector. Nice that all you have to do is unbolt it, flip it and reattach).

Overall, I can't praise this design enough. Looking forward to using the Nimble, reliable bed leveling based on where my nozzle tip is, good cooling, and the upgrade to a V6 hotend. Also glad I sprung for the effector piece to be professionally done in nylon - this thing is sweet!!!

Now I'm off to do wiring for this and a new Azteeg X5 mini which is a whole new learning experience.

Going to remove those prototype pictures so no one else is confused. And as you noticed, I switch the Nimble for left hand to right (or was it right to left?) It is the opposite of how it was shipped.

I had planned on trying to find the exact length bolts but found that using the nuts like this works fine. Sorry for not pointing that out.

I'm trying this again, this time with a shop that does Nylon. Part of my problem was trying to work with the piece before getting the Nimble/mount/Piezo20 together as a unit and then mounting the hotend up through the effector and locking it into the Piezo20 and then making the final step the careful insertion of screws through the Nimble mount and into the studs. The order of assembly turned out to be more important as it eliminates chances to torque those top studs. (I'm also hoping that my Piezo20's arrive with a bit smaller footprint than my ABS printed mockup as I had to trim a bit to fit it between the remaining bits of studs I had left from my last attempt).

Thanks for the Molex info, I ordered enough to make up 4 sets.

One last observation, the little notch at the bottom of the cooling fan mount to allow space for the fan's bit that holds the halves together either needs to be wider (variability in these fans from one manufacturer to another), or get rid of the notch and trim the bit off the edge of the fan. The mount is quite snug and holds that side of the fan together without it.

I just uploaded a new version of the Effector that has a wider and deeper notch.

I had already widened and depended that notch from the original design. Using the original creator's link for the fan, I order from that and it was still a tight fit. Will widen and deepen it some more.

What sort of prices are these shops charging you?

When I put mine together, I placed the Piezo mount down between the posts and slide it back so I could slide the hot end up into position. I then slide the Piezo mount around the hot end and attached the locking part. I then placed the Nimble mount threading one of the outer screw most of the way. Then installed the two screws to hold the Piezo. Added the second pillar screw and then tightened.

If the layers separated on the ABS version, it sounds like they may have had the hot end temp too low.

A full set of ABS parts for this including shipping was about $42. Just the Effector in nylon including shipping was $95 (I know, but I want this to work and be pretty robust). They did come back before printing in nylon to ask how critical the knife edge that splits the cooling air flow was. Their software shows that sharp angled edge was not going to print well. I looked at the ABS print and it was more rounded than sharp. For a purist, this might make a difference but in practice, it will have no real effect on the air flow.

After playing with this, you can hold off screwing into the pillars until last but I think I'm going to drill out the holes on the mount to the pillars - first to give it a bit of freedom if the pillars are not 100% vertical due to sagging and second, so the only place the threads are working is in the pillar and not binding on the mount (a lot easier to tighten down if you are just calling the mount a "washer" instead of it being a second "nut" that has to go tight up against the top of the pillar without stripping the thread of one or both). Just wondering if 1-2mm deep holes for the pillars in the bottom of the mount plate might not help to hold alignment during assembly (would have to add the same amount to the pillar height). Maybe not a good thing for some of us "support challenged" printers.

I'm hoping to cure a lot of problems with my first homemade Kossel Mini:

Hall effect probe is not 100% reliable and not a true indication of my nozzle height.
I built mine upside down intentionally to make the wiring a lot cleaner with everything on top and power supplies and switching running up the back of the Z stage. The problem is that it coupled bed leveling and belt tensioning. Pretty to look at but clean prints would be a lot nicer.
Replace Traxas rod ends with magnetic ball joints (this plus the Molex connector will make servicing much easier)
Replace an older E3D hotend built from a kit that jams using PLA with one of the newer ones that is prebuilt and heat cycled. (my guess is that being a Bowden tube version, it is an issue with heat migration up to where the Bowden tube seats along with a not perfectly vertical Bowden tube entering the hotend or possibly a badly seated nozzle during assembly)
Use a Nimble direct extruder and get rid of a meter of filament spring inside of the Bowden tube and get perpendicular feed down the axis of the hotend, plus the biggest gain - the ability to easily change filaments
Silicone socks for the hot end - not just a fashion statement! (Don't know why filament always curves up to start. Sort of like going to the dentist and they tell you to spit in the sink - even with my head below the counter level in the sink, I can still miss)
Carriages with adjustable endstop screws so I can do manual leveling
And replace my borosilicate glass that now has a huge piece of surface glass missing caused by an over-adheared ABS print that cooled unevenly.

The holes on the Nimble mount should be large enough for the M3 bolt to slide through without having to cut threads. The only place threads should be holding is in the pillar.

That answers a number of questions. If I hold up one of my failed PLA attempts against the ABS one I had printed, the ABS one is a solid 3mm smaller between the mounting holes for the ball studs (can you tell me what this should be for my carriages), an M3 bolt doesn't fit through the mount's holes without threading, the undue stress on the pillars trying to get the M3 bolt into it, the fan slot having problems fitting (the fan slot is fine on the PLA attempt so didn't have to be modified), and what was going to be my next question - why the piece of PTFE from E3D not fit through the mount's center hole.

Either my printer is not calibrated or I paid $42 for a print that is 95% of the size it should be. Don't mind spending money for quality but hate to just p**s it away!!!

And the spacing between ball centers is 48mm

Sounds like the shop isn't taking ABS shrinkage into account. ABS shrinkage is the source of its warpage problem. This is just another reason I won't ever print with ABS.

Just got the Effector piece in Nylon - makes me wonder why I'm trying to do "any" 3D printing myself. This part is absolutely stunning!!! Everything is exact on all the critical measurements, the holes are all perfect, and all holes thread nicely without fear of things snapping off. The only issue was I still need to use a modified fan as I gave them the STL before you widened the slot.

Here's hoping that my Piezo sensors are waiting for me at the post office today. I assembled my Nimble extruder this past weekend and immediately ordered another for a different printer. This thing is brilliant.

Glad to hear it's working for you.

The two upright posts that hold the mount for the Nimble extruder and Precision Piezo20 are extremely fragile - just trying to safely put a thread in them snapped one and then trying to set up a fixture to hold the piece in place for gluing popped the top off the other one. May I suggest a thicker wall with a hole on top. Or skip the plastic stud and just do holes where metal spacers, bolts and washers could perform the same function (just thinking ahead to the first time I have to fight with a stuck filament or I need to remove the drive cable to the Nimble which will likely also crack these plastic studs). Love the idea of it all being printed but ABS and PLA have the same problem as any torque breaks at the layer boundaries which is the weakest direction. If the mount formed a box around the Piezo20, with one side open for the circuit board (and for inserting the Piezo20) and part of the opposite wall open to lock the E3D in with the wedge, it could be screw mounted down through the Nimble mount and top of the box, eliminating most of the torque issues.

I use PETG for parts that need the strength. I haven't had any issues like you described with the ones I have printed (and I printed a lot getting it designed). I think I saw that you had it sent out to be printed? Do you know the settings that were used and what material it was printed in?

Where are you located at?

ABS, 2mm skin, 50% infill and the print was beautiful except for the time I had to spend cleaning the support out of the cooling ducts. I've personally tried to print both in ABS and PLA but couldn't get the central support settings right so finally had a shop try it for me (you don't by chance need any solid blocks filled with support - I have a bunch). The shop didn't offer PETG, just ABS and PLA.

I'm located in southern Maine with my printer temporarily set up on the bar which is convenient as this can drive anybody to drink.

Can you post the model/#pins for your Molex connector please? I now have everything made or ordered except that.
Thanks,
Richard

I ordered the parts from DigiKey.

Male Pins WM1000-ND (0002062103 Molex part number)
Female Pins WM1001-ND (02-06-1103)
12 Pin Plug WM1215-ND (03-06-2121)
12 Pin Receptical WM1214-ND (0003061121)

Note that Molex has announced the end of life for the 12 pin parts, but there are replacement parts for them. They are basically discontinuing the connectors without the pre-bent ears for the pre-bent ones. Just don't have the new part numbers right now.

Hi,

I've built the Jerry 226 variant, using Traxxas style arms. I really like how you have done your effector.

Would you consider remixing one with the spacing and mounting points needed for traxxas rod ends?

-M

This maybe too late for you but ElmoC remixed this effector from me, and I have made a traxxas version.

I don't have anything that uses traxxas so I wouldn't have anything to test changes against. But from what I have seen on effectors that use them, there might be some issues with the part cooling fan. How far apart are the centers for the traxxas you are needing? The balls on here and 48mm.

The design I am using is:

http://openbuilds.org/builds/delta-six-jerry426-variant.4005/

The effector and carriages are designed in such a way that the traxxas balls extend out the sides ( as opposed to the magnetic, in which they face forward or at an angle ). As far as I can see ( measuring inside Tinkercad ) before the Traxxas balls are added, the effector spacing is 75mm.

https://goo.gl/photos/BAzpMJYpAQx8AJUs5

75mm doesn't sound right. Mine are 48mm so that is almost double what I have now. It would take a fair amount of reworking to get it. I am working off a STEP file to make my changes. Maybe you can bring that into Tinkercad and make the modifications.