Building an Ormerod

So I've finished building my Ormerod and done my first print, and there are a few things to sort out.

This is my first 3D printer and I tried to follow the instructions on the RepRapPro website with the photographs. I got a few things wrong and found a few weak areas. I should say I'm an electronics engineer who switched to software engineer very early in my career, so fiddling with hardware is not unusual for me.

• I put the large connector on the ribbon cable on the wrong way. I should have paid more attention to the markings on the cable in the photo rather than the description.
• The Y axis bed and band - locating the band in the MDF bed was fiddly and eventually fell off during printing. I've since fixed it in place with a cable tie.
• The X axis band fitting on the motor in a recessed hole with the motor in the way was the fiddliest part of construction. I think I got it to work by sheer luck.
• Somehow the photographis of the extruder assembly confused me enough for me to put it together wrong. Burr on the plastic component prevented it all sliding into place.
• Getting the plastic cogs on the motors was very tight. I had to use a wood block and hammer to make them fit. Then I descovered I'd put the extruder motor cog on upside down!
• I've never done crimping before so I mangled the connector for the bed thermistor. I had to remove that and replace it with a better connector.
• The Z probe connector has lugs that simply get in the way. I've no idea how that was supposed to work. It seems to work itself loose, so I thought. Sometimes, even now after I've made some improvements, homing X fails.
• The documentation for homez.g doesn't mention you need to update homeall.g as well otherwise when a print homes all, it can do the wrong thing - like bury the head in the bed.
• Homing Z is very fiddly, I've had to raise the head by 1mm to prevent it from dragging across the print as it starts.
• I'm not the neatest or patient of people so the tape on the glass is bubbly.

The fact that it's now built means that part of the fun (for me!) is over. Now it's time to try to make it work reliably. The documentation seems to hide temps for the bed and head (head is 200C for PLA, 45C for the bed). Also, I had to create a simple cube reference print myself - seems a few simply shapes would be useful that would (i) quickly check everything and (ii) satisfy those of use who want to see something!

I took about a month to put it all together, in whatever evenings I had spare. I took my time, but there were moments when it got all to fiddly for me!

Edited 1 time(s). Last edit at 06/12/2014 03:24AM by imekon.

You seem to have had experiences similar to others I have seen posted here, and quite similar to mine. Some comments:

• As for the Y axis belt, there is a very elegant fix with iamburny's belt clamps, but you need the printer up and running before you can make those.
• Getting the drive gears on to the stepper motors for Z and E can be tight, but it is probably better to use a small round file to make the hole slightly larger, rather than using blunt force and risk damaging the stepper motor.
• The tabs on the connector for the Z probe indeed are in the way. I just cut mine off to get the connector to attach at all, even then it wasn't very reliable. Have since upgraded to dc42's sensor, which has better connectors.
• Crimp connectors are a bit tricky to assemble. I usually solder and close it up with pliers, and have gotten the hang of it reasonably well (been doing a lot of RC stuff, where those kinds of connectors are extensively used). I have occasionally used a crimp tool, but I found that very tricky to use for small connectors.

Quote
imekon

• I'm not the neatest or patient of people so the tape on the glass is bubbly.

For applying tape two strategies help. First and most important check out the wet application method. This is actually a lot easier than it sounds and really helps get a bubble free and gapless application. There are videos around demonstrating it like this. Second consider getting a reel of wider tape. One can go a full 200mm wide so it is just one strip, but even going to 50mm makes the job a lot easier.

Quote
bobtidey
Second consider getting a reel of wider tape. One can go a full 200mm wide so it is just one strip, but even going to 50mm makes the job a lot easier.

Having wider kapton tape means there is less patience required as it is fewer strips of tape, but it is a lot more difficult to get a 200mm wide one free of bubbles. Even with the wet application method it is rather tricky and I usually have to poke holes in a few bubbles. You only have to do it once, though.
I don't have anything between 200mm and 30mm, maybe 50-ish is the "sweetspot" for ease of application and patience required.

I too found applying the Kapton tape too tricky, so I dispensed with it. I normally print directly on the glass. There are a few tricks to getting this to work well:

* When doing large prints, the bed must be accurately level. But using bed-levelling screws is highly recommended anyway.

* Before printing, make sure the Z=0 position of the print head is set accurately, preferably in the centre of the bed.

* Wash the glass in hot soapy water, then avoid finger-marking the glass. Before each print, wipe the bed with vinegar. Cleaning it with acetone or isopropanol does not work well when printing directly on the glass.

* Use a slightly higher bed temperature. I use 68C. The actual temperature at the top of the bed is about 10C lower.

* In the slic3r settings, set the speed for small perimeters very low. In my firmware fork, I have reduced the minimum XY speed to 10mm/sec.

* If you are doing a tall print with a very narrow base, add a brim to get better adhesion.

If that sounds too complicated, then another alternative to Kapton is to paint solvent pipe cement (Marley KS10 or similar) on to the glass. You can dilute the cement with several parts acetone to make it go further and get a smoother layer. The cement tends to come off the glass with the print, so you have to patch up the bed between prints.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Dont worry too much about the bubbles. They disappear of their own accord after a few days. Dunno why but wait and see

regards
Andy

---

Ormerod #318
www.zoomworks.org - Free and Open Source Stuff

Quote
jstck

Quote
bobtidey
Second consider getting a reel of wider tape. One can go a full 200mm wide so it is just one strip, but even going to 50mm makes the job a lot easier.

Having wider kapton tape means there is less patience required as it is fewer strips of tape, but it is a lot more difficult to get a 200mm wide one free of bubbles. Even with the wet application method it is rather tricky and I usually have to poke holes in a few bubbles. You only have to do it once, though.
I don't have anything between 200mm and 30mm, maybe 50-ish is the "sweetspot" for ease of application and patience required.

Yes. 50mm is what I use and have no problem with it. Doing a new plate takes me about 5 minutes and I get 0 bubbles and tape butted together. The worst part is actually trimming the excess tape off the sides. The 'trick' I think is to use plenty of liquid. At first it doesn't seem right to be flooding it when you're sticking something, but then it just slides around very easily and then grips when you squeegee it out. I haven't personally tried 200mm as a roll is starting to get expensive but I think one would need to make sure the whole plate is well lubricated to stop any dry spots gripping it.

I use the 200mm tape found on Amazon and it works great and lasts ages. I apply it wet with a mist of water with a few drops of washing up liquid. I then squeegy out the worst of the liquid and leave to dry overnight. Pop it on the bed, heat up for half an hour and this will normally clear any remaining bubbles.

Regards,

Les

---

Pointy's Things
Pointy's Blog

Hi

Can I suggest an aluminium bed support upgrade ?

---

Another RS Ormerod Mk1 meets the world

Retired now but I used to make....
CNC Machined Mk1 aluminium bed support plates for the Ormerod
CNC machined X-plates and ribs for Mk1 & Mk2 Ormerods
CNC machined bed support arms for the Mk2 Ormerod.
Dual Hot-End heatsink blocks.

I wondered why when I unplugged the USB from the laptop all the lights would go out - I'd forgotten the jumper on the Duet board. D'oh! I see my lack of attention to detail is working hard again.

So, I hooked it up to my LAN and saw the web page for the first time. Uploaded a few test objects and tried more prints. Definate issue with lifting off the bed. I'm getting a good 20x20x20 cube, but even that has a slight warp.

I've used Tinkercad to create the test objects - so far a small cylindrical cup, a cube, a small flange and a ring. I'll make them public on the Tinkercad site as they're good for testing.

Edited 2 time(s). Last edit at 06/14/2014 04:53AM by imekon.

I also gave up on using Kapton tape. I was not able to lever the bed properly and so either the nozzle damaged the tape or the PLA did not stick. I print directly on the glass like DC42. Even though I am using 57° the PLA sticks good as long as the bed is heated. This does work even with ABS (bed temperature 100° and no need for hair spray or something else). But as DC42 already told - the levelling is a very big problem. The glass needs to be very clean. I am using glass cleaner.

I've found simply wiping the bed before printing makes quite a bit of difference, usually when the bed is up to 60C.

Hi

My two peneth worth:

Again similar to DC I currently print directly to glass, temp 57C for PLA and get very good, reliable results.
Kapton tape peels off on my prints, bubbles, leaves line in the print bottom and can be torn by bad alighment of the head.
Which I do by hand in about 3 minutes using a 6mm drill bit also have the aluminium bed support, haleluja to Dave for this.

Before hand, I scrub the glass surface with a dish cloth, foaming with suds from washing up liquid.
A small amount in the corner of the cloth does the job.
Then I run warm water from the tap over the glass to get rid of the foam and any residue.
Finally I wipe the glass squeeky clean with paper kitchen towels.

This removes all the dust, oil and grease from finger prints etc, I do the same with my glasses, makes then ultra clean to look through

Everyone save your money and try washup up liquid, no need for vinigar, acetone or anything else, just plain cheap cleaning products.

The only issue I have found with the Ormerod is with removing the print afterwards, until I took my partners advise, she said let it cool down to be past comfortable to hold in your hand then put the glass under cool running water. Obviously not hot to cold water that might fracture the glass.
You need the glass to cool slightly quicker than the print so that the stress between them causes the print to pop off.

This happens automatically on my Mendel as there is no insulation under the heated bed and it cools quickly, but the Ormerod cools much slower due to the card insulation.
Hope this is helpful.

Edited 1 time(s). Last edit at 06/16/2014 03:58PM by ezwul.

I recently got my Ormerod and finished building it!

Some of the problems you mention I recognize!

The cable connector that goes in to the Zprobe has pigs on it that make it not fit in the correct orientation.
I simply clipped of the one closest to the hotend so it would fit. But then it would sit really lose. So I used a zip-tie to attach the cable to the filament tube and it would stay put while the print head would move.

I also got the Big connector wrong on the ribbon cable. And sins I am not alone I would think it points to rather confusing instructions.

The Bed belt was very fiddly and I had to use an extra zip-tie at the end before it makes a loop. But with that it seams to work fine
The Other belt was very very fiddly to get through the motor housing part. But with a small screwdriver I could hold it towards the teeth and slowly turn the motor.

I accidentally (mostly out of impatience) missed most of the fine tuning post build. And started to print right away.
Fortunately I was lucky and my prints are surprisingly accurate

The plastic piece that holds the Z motor to the aluminium part broke for me when I screwed it on. Even though I was very careful not to tighten to much.
Think it was a bit of a failed print. But it still holds the motor well enough

The Recommended tools for the Ormerod build needs to be revised.
It tells you to get a 9mm spanner (non adjustable) aswell as an adjustable spanner.
The 9mm fixed spanner is totally useless as fare as I can tell. Not a single 9mm bolt or nut anywhere to be seen.
Still Im sure I get some use out of it some day

The recommended tools list needs to specify a pencil sharpener!
I have not owned one of thouse in 20ish years lol. So I had to sharpen the tube by hand with a sharp scalpel.

Also a hand chuck for drills came as a surprise to me. Don't remember it being on there but might just have missed it.
But solved it by sacrificing my fingers
I thought I had a 2mm drill but it turned out to be a 2.3mm drill. Witch would not fitt the bras nipples.
But turns out that removing them and then hand drilling out the tube with the 2.3mm and putting it back worked just fine

I was reading this forum for a while before I got my Ormerod.
So once it was build I instantly loaded dc42's firmware and iamburny's Webinterface.
And I must say it is AWESOME! Just absolutely love it!

I had a go at printing something a bit bigger, a front panel to a box. It got so far, then there was a loud snap sound, and I found it had slipped about 1cm on the Y axis. I aborted after that. Looks like my cable tie on the belt wasn't enough, ho hum.

Instead of a hand chuck, clamp a drill upright in a vice (or with pliers) and rotate the part into the drill rather than rotating the drill into the part.

Dave
(#106)

Getting better - learned a few things:

• Bed needs to be clean
• Z0 is critical - too high and you get lifting; too low and it can't feed and squashes everything
• Get the bed level, level compensation helps

So I'm printing merrily a side panel for a spool holder. It's about halfway through the print. It stops. Then it seems to reset, and start reprinting as if from scratch. There are now awful sounds as it tries to drag the head through the printed output so far... I hit the reset button.

I cleaned it all, and it seems to have not suffered. So I tried again, same panel. Tried through the web interface, nothing happens. Check... seems the file is corrupted, so I upload it again. Now it prints just fine.

I have noticed sometimes I can't see my printer on my LAN.

Which firmware are you running?

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
imekon
So I'm printing merrily a side panel for a spool holder. It's about halfway through the print. It stops. Then it seems to reset, and start reprinting as if from scratch. There are now awful sounds as it tries to drag the head through the printed output so far... I hit the reset button.

I cleaned it all, and it seems to have not suffered. So I tried again, same panel. Tried through the web interface, nothing happens. Check... seems the file is corrupted, so I upload it again. Now it prints just fine.

I have noticed sometimes I can't see my printer on my LAN.

I had corrupted files to start with Turned out the SD card was not very good.

regards
Andy

---

Ormerod #318
www.zoomworks.org - Free and Open Source Stuff

Still on 0.65e

Quote
imekon
Still on 0.65e

Then I suggest you upgrade it, either to RRP's 0.78 release [forums.reprap.org], or my 0.78a release [forums.reprap.org]. See [forums.reprap.org] for the differences. The 0.65e release you are running contains an acceleration bug, which could be responsible for the pause you experienced.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].