Xnaron Printable Magnetic u-joint option for Rostock Max

[Flateric]

If my memory is correct, and I may be wrong here, you need 200 AMPS sustained to create a decent bond. (Or was it 800, hmm, I'll see if I can figure this out more accurately for ya)

[Maco]

HI anyone seen this ?

http://www.igus.com/wpck/3748/igubal_Gelenkkoepfe

looks like a good parts for the rostock

Anyone wants to order parts and make a group purchase?

[nitewatchman]

I have used a LOT of IGUS products over the last 25 years, they are very good people to deal work and their stuff as always done what they said it would.

nitewatchman

[Polygonhell]

Someone on the deltabot google groups forums used those a while back, I'm sure they are probably fine, you could go search through the archives.

[cambo3d]

pretapped steel balls..

http://deltaprintr.com/shop/hardware/10 ... eel-balls/

[Boundless]

Thanks for the link cambo!

Ordered 12 and get this... shipping was only .34 cents! Crazy.

[critical_limit]

Hi,

ordered the steelballs mentioned above. Due to I´m in germany I converted all other things to metric.
Hardware is on the way and while I´m waiting for it, I made a effector with metric dimensions and ready for a E3D V6 Hotend.

As soon as I´m at home I will start printing in Nylon (Taulman Bridge). Never tested it, but hope to manage it with my E3D V6 and .25 Nozzle. Otherwise I will print with ABS. Arms will be made of 8mm CFK-Tubes.

[noishi]

nice! good to see a cheap source for pre-tapped steel balls

[Tincho85]

Hi guys, is someone using magnetic arms? any pro/con?
Is the upgrade worth it? if not, why?

To be more precise, I would love to read an honest review from someone ho has been using them for a few months.

[Behold]

Me too

[Tinyhead]

I used them for a number of months, but ultimately went to the trick laser arms.

Pros:
Quick changing hot ends (if you have multiple types)
Nice lines as there is virtually zero play

Cons:
Failed prints from effector coming off

I had MANY failed prints because of this. If the hot end hit a snag, a lip, or an upturned surface from an overhang or anything.... done. I would often come to my printer in the morning to find a big rats nest of filament and the arms flopping around as the printer was still trying to work.

Great idea in theory, but for me, it wasn't worth the effort. I'm much happier with my trick laser arms.

[xnaron]

I have been using them for a couple of years now. I have never had the effector come off like that. Could be I have my settings tweaked and don't run into those issues. It's always a possibility for it to come off. I wouldn't recommend anyone print unattended. There is too much risk of a fire.

[Tincho85]

Maybe you have more powerful magnets?
Don't know if there is a pull force value or something.


Either way, thanks for the feedback guys.
I might try one day this mod.

[xnaron]

Maybe you have more powerful magnets?
Don't know if there is a pull force value or something.


Either way, thanks for the feedback guys.
I might try one day this mod.

Yes the strength of the magnets I chose was a very important part of my design.

[KAS]

I used n52 magnets, although I think my issue was more in the pre-tapped steel balls. I found it difficult it to measure and align on the effector and carriages when you don't have a set spacer between the ball and item. Trying to use the screw to adjust the overall length accurately on everything was my downfall. I think using the cap screw with the ball glued to would be easier to adjust.

[Tincho85]

- Magnets http://shop.revolutionmachines.com/3-8- ... 8-12pc.htm (BE CAREFUL NOT TO LET THE MAGNETS SNAP TOGETHER AND NEVER USE PLIERS ON THEM. THEY ARE FRAGILE AND CAN EASILY BREAK)

Hi Xnaron, I thinks that link is dead. There are no 3/8'' magnets.

We need N52 3/8'' magnets, but of what thickness? more thick = more pull force (Magnets)

3/8" dia. x 1/4" thick = 8.49 lb Pull Force
3/8" dia. x 3/8" thick = 9.86 lb Pull Force
3/8" dia. x 1/2" thick = 10.5 lb Pull Force

and if we use larger or shorter magnets, the arm lenght would be different.

- You need to #define END_EFFECTOR_HORIZONTAL_OFFSET 36.5 in configuration.h for the new effector. (if you don't do this you prints will be too large)

Could someone explain this please? I can't really understand how the delta geometry works.
If I don't change that value... the print will be bigger in every way? or just x-y?
The EEPROM horizontal radius won't fix this issue? I mean, when doing the z calibration process.

[Polygonhell]

The only thing that impacts z at the center of the build plate is the steps per mm, the rest is really about knowing how long the arms are and knowing what the angle is when at the center of the build plate.

All the horizontal offsets have the same effect, they are just subtracted from the printer radius to compute the length of the arm in the horizontal plane form pivot to pivot.

The problem with making arms is they have to be the same length to tenths of a mm, and you have to know how long they are with similar accuracy. If you don't you have to experimentally set both the arm length and the radius, and they both can compensate for vertical offsets at the towers. If you don't correct with the right setting you can introduce issues with effector motion between the towers.

[Tincho85]

Thank you Polygonhell. I need to write it down, so I can process the new data lol

First I need to make the arms exactly the same length, so they can form a perfect parallelogram. I don't want to know what could happen if there is a small variation.
If they end up beign equal to the stock ones... great, if not, change the dimensions in the firmware.

EDIT: To be sure. 269mm should be from each center of the balls right?
[img]https://farm8.staticflickr.com/7649/168 ... 9fa9_n.jpg[/img]


As for the horizontal offset. I might use the value that Xnaron says, print a test cube and see what happens.
Maybe everything will work just fine! If not, I will be back

[Generic Default]

I have done a bunch of arm mods for the last couple years, mostly with magnetic arms. Here are some things you need to consider;

1) Arms are fairly straight
2) Arms are rigid. Metal tubes or CF preferably.
3) The length from ball center to ball center must be the same for all six arms to within 0.1mm.
4) The strength of the magnet is not enough to hold the arms on near the edges of the build area if your arms are not the same length.

You will not get a great setup with magnetic arms without some big calipers to measure with.

[Cleveralias]

I got outstanding results from the magnetic arms but my first set was starting to look a bit worn after many, many days of use. I had planned to redo them using nylon for the cups and the pre-tapped balls linked in this thread; however, I had a sample of the Igus Tribo filament that seemed too perfect for the application to pass up.

The Tribo seemed a bit brittle by itself and after experimenting with it for a bit I wasn't sure I'd have enough to make all the ends. I tested and discovered it is soluble in acetone, so assumed it may have an ABS component. I checked it's bonding strength when layered with ABS (pausing and switching filament) and found that adhered very strongly! So I was able to make just the cups using Tribo and ABS for the cavity where the magnet and CF tube attach. I've got a few hundred hours on the setup now and it's holding up great.

I highly recommend you request the Tribo sample from Igus (http://www.igus.com/wpck/11723/N14_4_1_ ... ?C=US&L=en). They shipped a very nice kit with their catalog on a flash drive and an Igus branded screwdriver. I was very impressed with the package they sent.

As to sizing the arms, this time around I simply bolted some L brackets to a 2x4 and bolted up the balls before the adhesive had set. I was very pleased that all of my arms were within .01mm of each other.

[Tincho85]

Hi guys, I need a little help... my brother is in Barcelona atm and he will be staying there till April 10.
I wan't to buy 12 N52 3/8'' x 3/8'' magnets or 10x10mm but I can't find them. Google is failing me...

Getting them from outside Europe won't work because of shipping timing.

Someone knows where I can buy them? He won't go to a store, so I need to buy them from here.
Please help!


PS: I've found these: LINK N48 10x10mm with 4.2 kg pull force VS N52 4.47 kg pull force.
Will they work? shipping to Spain is 2-4 days so they prob arrive on time.

[Tincho85]

Never mind, found a friend from a friend from a friend that will bring me the magnets from the states.
Bought these ones: https://www.kjmagnetics.com/proddetail.asp?prod=D66-N52

[jsnbrgg]

So it sounds like from reading about this project that everyone in this thread prefers KISS Slicer, correct? I've never tried it; do you think it gives you more presice prints? Also, I might have overlooked it, but where can I find the STL file for the pyramid you guys are printing? I want to try out and see if I can get my machine fine tuned this good.

Thanks,
J.

[jsnbrgg]

What percent infill did you guys use for the parts in this mod? effector, rod ends, cheapskate ball ends, etc.

Thanks,
J

[gestalt73]

Hey jsnbrqq,

Here's a link to the calibration pyramid:
http://www.thingiverse.com/thing:8757
What's fun about that model is that it's a balance between print speed, print temps, retraction, and part cooling.

As far as slicers go, I've dabbled in Sl1cer, Cura, Mattercontrol, and KISSlicer.

KISSlicer wins, hands down for most everything I throw at it. Mattercontrol is also very good, and would be my second choice for a beginner.
Others have favorites, or favorites for certain types of prints. For me, so far you can't go wrong with KISSlicer.

For the effector parts, I've been printing 4 perimeters, 1.0mm skin thickness, 25% infill and getting great results.