Talk:RepRap Morgan extended BOM

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z-bracket

Hi Robert,

I too want to build a morgan but have been waiting for Quentin's updated instructions. I'm tired of waiting. Seeing stellar work like yours makes we want to build. The group in Charleston has put together some good material.

Interested in your work on the 12-z_bracket. Somehow, I have two of the z-brackets with the tear drop cutouts, one with a triangular back-plane structure, like in current github/stl for morgan, the other like yours with only the single back-plane.

Also, interested in your use if the steel drive shafts. Where did you get your 15mm and 22mm pipe?

Thanks.

Steve

Hello Steve,
glad to see my work being appreciated. I found the steel tubes in our local DIY market.
Both have a wall thickness of 1mm and are very smooth and strong and they were less expensive than in copper. You should pay less than 1,50€/m.
Maybe standard steel-c-pipes (they have 1,5mm walls) would do it too. You'll find a lot of these at ebay below 2€/m.

info on captive nuts

Hi there,

Been waiting for response from Quentin for several days. Was talking with him about the drive shaft assembly, he described the nuts pressed into the sides of the 15mm pipe. Anyway, I responded back asking how far from the ends do the captive nuts get pressed into the pipe? and which end of the pipe goes on the threaded rod-do the captive nuts lead or follow, presuming their at one end. That's the question I've been waiting for an answer.

No response - very odd, historically he has responded very quickly. I know he's frustrated his instructions haven't been released.

So, I thought I'd reach out. If you can't help, I am going to the Charleston Makelab and ask angrychisel his opinion. Really wish I had better instructions. Have you made notes you can share? Thanks.

Steve

Hello Steve,
You should get the student version of Autodesk Inventor (it's free for students though). With that you can look at my virtual Morgan in every detail you need.
The story with the 15mm pipe goes like this: On each end you press an M8 nut up to 80% of its height into the pipe. This bends the ends of the pipe into the M8-shape (you can see that demonstrated in the extended BOM in the "Hardware"-part). So when you screw the pipe onto the threaded rod (with M8 nuts inserted in both ends) the shaped ends of the pipe hold the M8 nuts and it acts like a very long nut itself. Quentin uses this technique to stabilize the threaded rod so that it doesn't bend while printing (the threaded rod alone is not strong enough over long distances).
To press the M8 nuts into the pipe you screw an M8 nut on an M8 bolt. Then you insert the bot into one end of the pipe until the nut stops the insertion. Then you can press the M8 nut further into the pipe by knocking the M8 bolt into the pipe with a hammer.
With a copper-pipe this is quite easy and doesn't need much force. With a steel-pipe you should support the M8-shaping of the pipe by using a vice on the pipe-end with the M8 nut in it. It is not necessary, that the nuts fit absolutely perfect, because they will stay firm once the pipe is screwed onto the threaded rod.
The direction of the pipe doesn't matter, because its symmetrically.
My virtual Morgan as a basis I want to make some small animated videos as assembly instructions. Or maybe someone is so kind to help me with that. It's a lot of work. But the model is there and realistic in every detail.
If you need more tips, feel free to ask.
About Quentin: I guess he just lost overview about all the questions in the forum. He is still answering fast, as far as I can see it. Maybe he just forgot some older questions, because he's quite busy I think.
Greetings
--RobertKuhlmann 20:22, 4 September 2013 (UTC)

re-peat captive nuts

Hi Robert,

I must be just thick-headed. You gave a detailed response. Mostly made sense. Thank you.

The problem I have is I keep expecting to see nuts pressed into the sides of the 15mm pipe.

Every image shows nuts on the threaded rod, only.

Quentin did get back with me. I responded to his 'Lillian' post and asked again. His answer made me a little confident. "Press the nuts in the sides near the end of the pipe." Again, never seen an image. Likewise, don't understand their use being horizontal to the vertical threaded rod. Never see ref to inserting a bolt across the pipe into the captive nuts..

I got my drivewheel hole widened to fit my 3/4" copper. So, I may be on the cusp. I didn't get an email when you updated this-I'll keep an eye open.

Thanks.

Steve

Hello Steve,
do you mean you missed a picture like this one?
Steel pipe with M8 nut.png
The pipe has a nut on each end. This is to stabilize the threaded rod, so that it doesn't bend while printing. The threaded rod alone would be able to twist and bend a bit over its length. With the steelpipe around it, fixed by the two nuts, this doesn't happen.

Hi (Not sure about this editing) No - not at all. The image I'm expecting has the nuts pressed into the sidewalls of the pipe.

Hm. Why should you? The nuts are pressed into the pipe on each side/end. They are not pressed into any wall or into the wall of the pipe. That wouldn't make any sense.
I think you just didn't get Quentin right. He means it in the exact configuration I showed to you.
Regards
Robert

Hi Robert, Exactly my thoughts. But Quentin sent an explicit email where he described pressing the nut in the side-wallof the pipe. That's the whole 80% insertion depth. Maybe I misread the original 'drive shaft assembly' section. Thanks for your help. Guess I'll skip it.

Steve

Extruder block

Hi there,

Do you have and work done on the extruder block, idler, gear

You find the resp. parts in the extended BOM. But they are only repaints of the Prusa-extruder-parts. The RepRap doesn't need a special extruder, except is has to be a bowden type.

I've got my frame built and trying to work the details. Motors get installed tomorrow. Not sure how the Z-motor attaches - only have 2 motor mounts.

The z-axis-motor is placed on the top-platform, the motor-axis pointing downwards. The axis is coupled to the lead-screw via the leadscrew-shaft-motor-mount.

After following your GREAT work, and a bit of Quentin's I've got a few pieces still in the box.

Tightening cones ? Never saw a place for them.

I don't either.

Where do the hall endstops go and what are the details for the magnets.

There's a detailed descrition in Harley's forum. I will transfer it to the wiki later on.
The holders go to the smooth rods of the z-axis, right above the resp. drive wheel. The magnets are placed in one of the small round pits on every drive-wheel. The endstop holder holds the sensor in a way, it can detect the magnet in the resp. drive-wheel.

Also, don't even know where the rear bed-clips go.

Take a look on my personal Morgan-Page here in the wiki: User:RobertKuhlmann/RepRap_Morgan
You'll find some detailed pictures of the platform there.

Curious if my 3/4" pipe is too long - sticks out 3" above the upper platform.

That's intended, because the moving arms shall not collide with the x-axis-stepper motor.

May be too far to the heated bed - should I plan on raising the bed. Measurement specs would have helped

Maybe my Morgan-Page (User:RobertKuhlmann/RepRap_Morgan) can help here too.

6805 bearing adapter ?

Yes. It holds contact between the 22mm-z-axis-pipe and the 6805-bearing in the z-mount-top, making the z-axis sit stable from bottom to top.

For Q:"Frame Assembly" #16, my 3mm bolts are only 6mm by the BOM, looks like the motor coupler needs more of a 20+mm 3mm bolt. Otherwise, where do these 6mm-3mm blots go? Keeps saying three for the motor coupler and I only see 2.

The 3 M3x6mm bolts can be used as a replacement for 3 grub screws to fix the lead-screw-shaft-motor mount to the motor axis. You need to place 3 M3-nuts in the head of it. The lead-screw is fixed by two M3 x 20mm bolts with two M3 nuts.

Plus, all confused by Quentin's Q:"Frame Assembly" #17. Does the spring go inside the z-bracket? Plus, 8mm isn't long enough, the z-bracket is like 50mm wide. I didn't even get two leadscrew nuts. Quentin seems to want one on each side of the z-bracket.

I'll publish a drawing for that.

Those and the bowden adapter are still in the box. Not sure where these pieces go. I need to ask Quentin too, but I may just focus on the extruder block with him. Sorry so wordy. Hard to find anyone ahead. Any help appreciated. You could email if you prefer at

Answering question in public is preferred, because readers with similar questions may be interested in the answers as well.

Thanks.

Steve

Answers are embedded in your text. And please don't forget to sign your posts (2nd last button above the editor window) --RobertKuhlmann (talk) 07:36, 25 September 2013 (PDT)

Leadscrew nuts and the anti-backlash spring

Hi there,

Looks good. What I expected except the BOM only lists one (1) leadscrew nut. Guess I'll need a second made.

Suggestion, maybe you add the dimensions of the spring? Diameter and length? Drawing is solid. Thanks.

Done. I've corrected the quantity in the list and added the dimensions of the spring to the assembling instructions. --RobertKuhlmann (talk) 14:31, 25 September 2013 (PDT)

ML6 - Detail C, toolhead

Hey there,

Just reviewing my build. Looking at the ML6.pdf, noticed detail diagram C. I see the two screws that connect toolhead to the arm. However, you left off the two bolts, M3 I think, that are used to secure the J-head - maybe 20mm. I guess it needs nuts too. Want to help make those diagrams nice - I know I needed them. Thanks for your work.

You're welcome. I'll correct that. Over the time this project will become better and better. :) I love it. --RobertKuhlmann (talk) 00:19, 26 September 2013 (PDT)
And done. --RobertKuhlmann (talk) 00:33, 26 September 2013 (PDT)

Turning the corner

Hi Robert,

Things are going well with my build. But I can't figure out how to add an image.

Anyway, trying to solder up my hall effect endstops. I keep breaking the legs off. All set with the two on the vertical smooth rods. I've got one above the top wheel and the second below the bottom wheel. Now, I just have to figure out the magnet placement based on a Quentin fan's drawing of "home" and "psi-0", etc. Any answers there appreciated.

Anyway, I have got a set of morgan parts I am going to sell on ebay. I was reviewing my parts and the BOM and noted there were three end stops. Where does the third end stop go? It seems like it would be best for the leadscrew, but can't figure it out. There's no way I think it can reach from the smooth rods and I see no where else to hang the last one.

I appreciate your prior reference to your bed layout. Unfortunately, the smaller pair of "lifts", the front mountclips, on the front of the bed weren't designed when my parts were built. I guess I'll just put one on each copper pipe. Hopefully it won't effect leveling.

I feel close. I still have to download software, which unfortunately Quentin hasn't detailed. Figuring Arduino SDK first, then Pronterface and python, then slic3r I guess. I am a software/database guy so hopefully not too rough.

Hope things are well with you. Haven't seen an update in a while from you. How's your homemade heated bed going? Would be nice to have a bigger heated bed area.

Steve

Hello Steve.
Adding an image, even on the discussion page is quite easy. You have to use the "Upload File"-link on the left side (under "Tools"; I only see the German descriptions, so the linkname may vary from my translation). Upload an image file (PNG or JPG). Copy the Wiki-link (shoulöd look like this: "File:MyUploadedPicture.png") and place it in the text with double brackets:
[[File:MyUploadedPicture.png|300px]]
(The "px"-value controls the display size of the picture)
I'm feeling fine again and made some updates the last days. I was struggling a bit with my job and my career and had to reorganize my workplace, but all that is on the right track now and work on my Morgan continues.
My new heated bed is etched and in place already (see the latest update on my personal project page): User:RobertKuhlmann/RepRap_Morgan#Progress_of_my_own_Morgan
I will design a bigger heated bed, as soon as I have some practical experience with my Morgan. In general it is not too hard to design a heated bed. You just need to calculate the resistance of the copper tracks (e.g. 135µm thick) and draw the layout with the needed track lengths. In my recent design, there are four sections in parallel, so the electric resistance of each section has to be four times the overall resistance I want to have (2.4Ohm in this case). Of cause each section should contain the exact same length and width of tracks to ensure equal temperatures everywhere on the building platform.
About leveling: Any placement and montage that gives an almost even building platform is okay, since the platform should be realized adjustable anyway.
--RobertKuhlmann (talk) 12:13, 17 October 2013 (PDT)

Hey Robert, Any thoughts on my questions regarding magnet placement and the "extra" end stop? Thanks. My-morgan.jpeg

Quentin designed the firmware in a way, that homing the z-axis drives it all the way down. So the z-end-stop may be placed on one of the smooth rods above the drive wheels,while the magnet can be glued to one of the platform arms, near the rod. --RobertKuhlmann (talk) 12:52, 21 November 2013 (PST)

Custom heated bed, 625x265

Hi Robert,

Figured out most - thanks to you in part. Still need to place psi magnet.

Anyway, how's your custom heated bed coming? I had been following the conversation, but you've all been quiet recently. Any update?

Also, regarding the wire. I know your using insulated copper wire of some small gauge, but I was wonering if the nichrome wire was an option instead of just copper wire? Likewise, what is the platform on which you lay the wire? If I use an aluminum sheet over wood, do i need to insulate the wires from the AL surface? Look forward to hear from you. Thanks.

BTW, what is your profession?

Steve

Hello Steve,
had a bit trouble the last days and some things came to a short hold. The bed of nails, that will form the wire for the platform, is almost ready (70%).
The wire shouldn't be made of NiChrome, because the resistance is far to high for this usage. The heated bed will be driven by 12V and therefore should have a resistance between 1.5 and 2.5 Ohm. NiChrome is okay for things where you need short wire lengths with a relatively high resistance (compared to the wire length).
The heat wire will be glued to one side of an aluminum platform. The platform can be fixed to and adjusted on the existing platform base. You don't need to insulate the wire additionally, because it's insulated already. But I'mnot sure if I got you right, regarding wood and aluminum. What are you planning to do?
I'll post pictures of the advance within the next days.
My profession: Software architect and designer/developer
My passion: Inventing things
--RobertKuhlmann (talk) 13:06, 21 November 2013 (PST)

Custom heated bed, cont.

Hi Robert,

I was thinking a thin aluminum sheet over a piece of plywood/particle board/MDF, whatever. I can buy a .025 sheet from the local hardware. I've been putting cork underneath for support and insulation.

Would likely use wood underneath to support the screws for the loops. Although haven't figured out a total length for wire yet. What gauge are you using? I know you comment regarding resistance, but I haven't measured.

Fun on the profession. I am an unemployed Oracle DBA for Exadata, former developer. Where are you? Always looking for contacts to figure out how to make a few $$$ somewhere.

I added a new topic because I wasn't sure editing would send the notice to you.

Hi Steve,
I'm notified of every change (even not working at the NSA though ;) ). No problem.
BTT: You did get something wrong from my description of the big heated bed. I'm building a bed of nails that is used to form the wire loops. The wire gets picked up from the bed of nails (e.g. with adhesive tape) and fixed on the underside of the aluminum platform.
I'm using aluminum with 3mm thickness, because I can drill threads into it for my version of platform adjustment (as shown in the BOM:Platform adjustment).
The length of the wire (and therefor the count of loops) depends on the diameter of the wire. :)
The loops shouldn't be separated too far, to ensure an equal temperature everywhere on the platform.
You need some simple calculations for that:
Assumptions: We want app. 100W heating power, using a 12V DC power supply.
100W (P) at 12V DC (U) need 1.44Ohm resistance (R) and gives a current of 8.333A (I).
R = U²/P
I = P/U
35m (l) of copper wire (with a specific resistance (s) of app. 0.01786Ohm*mm²/m) have a resistance of 1.44Ohm (R) at 0.738mm diameter (0.4278mm² (q) ). Thats something between 20 and 21 AWG.
l = (R*q)/s
q = (R/l)*s
So it's a good idea to design the loops first, measure the length of the wire, required for the loops and calculate the diameter for that length.
You can buy 50m of insulated copper wire with 0.75mm² (AWG21) (200g) for app. 10€ to 15€.
--RobertKuhlmann (talk) 02:02, 22 November 2013 (PST)

Hi Robert,

Did you see my photo above of my device?

BTW, I'm in Indy.

Yes, I didn't understand that you were moving the wires to be underneath. With your wires under your AL plate, will you be able to insulate? What material? Fiberglass? I was thinking to sandwich between two AL sheets. That would allow me to insulate with cork underneath. All this sits on top of my AL plate that screws to a base.

Thanks for the formulas. Guess determining the length is next. Seems to me, you could say 30-50m use 20 awg, 50-75m use 18 awg - or whatever, haven't done the math. Using your standard 2.5mm separation is fine. Does the coiling layout matter -zigzag vs concentric loops for instance. Does the wire heat from the middle? The resistance range helps. Looks like your aiming for the low end at 1.44O Thanks again. I'm probably a ways from starting-have to check my wire sources. I am going to try the larger bed printing PLA.

Hello Steve,
I've seen your photo. The platform arms are oriented the wrong way (top-down). You'll have to fix that. ;)
You don't need to insulate the copper-wire, because it is (should be) insulted already (e.g. with PUR). So you can place it direktly on the aluminum. I wouldn't sandwich the wire between two aluminum plates, because all this would become a bit heavy. Just use a 3mm plate with the wire glued underneath it. That's all you need.
The wire will be a bit hotter to the middle, but the aluminum spreads the heat, so you will hardly measure a difference. If the temperature difference between the center and the perimeter is too high, you can easily cut the wire in segments of equal length, and connect them in parallel to the power supply. Overall this results in the same resistance. But it's very important for all segments to have the exact same length in this approach.
Zigzag is done far more easily than a concentric loop, I guess. The shape doesn't matter, as long as the distances between the loops are very similar. A concentric pattern on a non-round that fulfills this requirement is very complicated, if even possible.
Finally: If you don't need a heated bed (printing PLA; that's what you intended I guess), there's no problem at all, but I think big PLA-structures need a heated bed to avoid buckling and twisting.
BTW: I'm living in southern germany. --RobertKuhlmann (talk) 07:48, 22 November 2013 (PST)

Morgan toolhead V3

Hi Robert,

I printed your toolhead v3 and was planning it on using it for my build, do you have more information on how to this mod with the extruder? i.e. how do you connect it and tighten it?

Thanks, Paul


Hi Robert

I too have been looking at the V3 toolhead. Although my question is in regards to the venting. It looks like the fan is set to blow on the hot-end and not at the nozzle. Is this true? My expectation was that the drip-area was where it was best to have the fan aimed. I may have that wrong-haven't seen a conversation regarding. Thanks.

Steve

Hi Robert,

I loaded the STL and looked a little closer. I see how the venting rolls around the center hole. BUT, that brings the question of how does the J-Head load? The hole in the center is only 10mm not the 15.87mm (5/8") needed. Any chance there's room to expand the hole? THanks for your response.

Steve

Quantity of PVC brackets?

Quick question about parts 1 and 2, the PVC pipe brackets. The images indicate that one needs only two of each part, giving us four. Intuition leads me to suspect that we need a total of eight. True? How many of each, and where are each placed? (I get that the difference is for access to the nut-recesses, but the placement is not obvious to me.)