First build - large Hex framed Delta - 3DR Mega style

Quote
GroupB
Why not use bigger hole in the effector for the ball so you can adjust them perfectly with something like a jig for spacing and a dial for the Up/Down? The jig then can also be use for the carrier. You can do better than 0.5mm , this is a important measure to get right, try to aim in the 0.05mm (0.002 inch), we talking about the tilt problem if those are not right. I know its hard and will take time to get that kind of precision but at the end you will avoid problem.

Good point, I'm going to do a small redesign to enable that.

Nothing I've read says much about the accuracy of the distance between the rods for rod spacing pairs, only that both ends should be the same distance apart. The rod length is written as needing to be precise and I'll be jigging that so all six are exactly the same.

However thanks goes out for the help for something that is all new to me and especially when I'm doing something different. I'd rather fix it before it's all together.

Cheers

I did not read anything that said rod spacing need to be accurate , I did not measure mine , but I made a flat bar with 2 hole where my balls sit and use that as a jig on 3 side of the effector and on the 3 carrier so I must have the same spacing around.

Im curious why use rod and linear bearing if you have a extrusion in the middle? why not a linear rail or some kind of Vslot carrier ? to me get 3 tower at the good position look almost a fun thing to do vs 6 independant rod ( took half a day to set my 3 tower)

How about having the balls screw into the carriages at 45 degree angles to the plane of the carriage? Then by putting shims under one or both balls, you could adjust both the ball spacing and the angle of the line between the ball centres.

---

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
GroupB
I did not read anything that said rod spacing need to be accurate , I did not measure mine , but I made a flat bar with 2 hole where my balls sit and use that as a jig on 3 side of the effector and on the 3 carrier so I must have the same spacing around.

mmm, it's given me an idea to split the effector print into three parts now to fully remove X/Y position errors of the triangular print and only deal with x errors by making the jig itself an insert into the effector. doing this could allow for it to be printed or made from aluminium bar.

thanks

Quote
GroupB
Im curious why use rod and linear bearing if you have a extrusion in the middle? why not a linear rail or some kind of Vslot carrier ? to me get 3 tower at the good position look almost a fun thing to do vs 6 independant rod ( took half a day to set my 3 tower)

Early in my working life I did a lot of telephone exchange fit out working with U channel, one practical lesson was span distance between supports with the seemingly unbendable u-channel being rather "flexible" over certain lengths.
Intuition said that 2040 T-Slot longer than 1000mm may well be more flexible than expected and for the 1520mm unsupported vertical length a larger sizing would be more sensible, however T-Slot is not easy to find nor is it cheap here in Australia so it is being used as a framing member not as a carriage bearing member.
Intuition was right btw, a quick test last night of just tapping the extrusion showed quite visible deflection and resonance vibrations that would definitely impact print quality, the same tapping on the 20mm rod showed nothing.
The T-slot as a framing member allows easy attachment of an external frame.
Why not linear rail..... well the linear rail attached to the t-slot would be affected in some extent by the flexibility of the vertical extrusion. wheeled carriages would be impacted even worse.
I'm now firmly convinced that t-slot is not the suitable as a carriage bearing member for tall printers unless you scale up significantly.

This is the scaling issue I've read about all the time as people scale up small designs to get bigger print areas by just using longer lengths of any item without scaling the item.

Your effector dont need to be precise if you allow your ball to move ( bigger hole) and using a nut or a screw in the balls, you just have to be precise when you do the alignment of the balls, so there no tilt, and if your center is not dead center that also not that important. I made my effector from .125 alu a triangle with 6 feet that I put 45 degree,my hole are not precise at all but my balls position are.

For me allow adjustment in a design is priority #1 , when you design with that in mind there less headache later when come the time to calibrate it and its allow certain parts to be a little off and easier to make/machine.

Like are you planing a system of some kind to adjust your linear rod position ?

Quote
GroupB
Like are you planing a system of some kind to adjust your linear rod position ?

Assuming you mean the vertical rods then no, the top and bottom corners are identical and the FFCP will produce essentially identical parts printed on the same part of the bed so all spacing is the same.

Cheers

Today was Aluminium cutting day.

Had to square up the drop saw first, lucky it is easy to do.

Sliced the 5 verticals to 1650mm long so they extend 50mm out the top for mounting options, this is 50mm longer than the 1600mm vertical rods (63")

Next did a quick jig to ensure all the base/top frame members were cut identical lengths, (345mm)


The drop saw is a 12 inch compound mitre saw with a 80 tooth tungsten carbide blade and it does a fairly neat job

As I had three corner brackets printed I couldn't resist just putting together the 3 main verticals...... now i start to realise just how tall this is going to be.......


Ordered a duet 0.8.5 today, so controller is decided.
Have dc42's paneldue and height sensor board ordered as well.

Just noticed I stuffed up a little on the corner bracket, four screws will need to be 25mm not 16mm like everywhere else.... now i need to order some 25mm M5's....
Wish the order of t-slot nuts would arrive in from China, hard to bolt anything together without them.

Thought I should post an update.

Things achieved:
32mm MDF base stand completed:
top cut out, still to be painted
heatbed platform cut out, still to be painted
Base hexagonal structure bolted together
2040 and 20mm rods placed in base.
2040 plum bobbed and then bolted to brackets.
top pulley mounts designed, printed and confirmed valid
rod carriages finalised, linear bearings inserted and tested on the rods.
carriages move well with no obvious binding with carriages comfortably falling under gravity to the base.
Tested string/spring setup with carriage/rod/effector.... seems to be workable, felt silky smooth moving around by hand.
End stop switch brackets designed and printed, using micro switches retrieved from new but excess Logitech mice.

DC42's height sensor (and paneldue board) have arrived. (thanks Dave)
Dyzend hot end ordered. ordered it with 300c thermistor first.
Duet 0.8.5 ordered, no sign it has shipped yet.
Ordered the new E3D Titan extruder, really wanted to get a BondTech QR but honestly the near AU$240 cost was just too much.
1200W 500mm heater ordered from aliexpress, it's shipped

The cast ALU plate has not yet been ordered, but it's nearly local so should only take a couple days.

It's physically coming together....

Where in aus are you?

---

RepRapPro Mendel 3 Tricolour
RepRapPro Fisher
-Carbon Arms
-Easy adjust Carriage+effector
-axis stiffness mods
HE3D -600 delta
-Duet 0.8.5
-PanelDue
-DC42 Height probe
-RobotDigg metal components
Simplyfy3D
RS Design Spark CAD

Quote
bgkdavis
Where in aus are you?

Canberra

guess someone has to live there

---

RepRapPro Mendel 3 Tricolour
RepRapPro Fisher
-Carbon Arms
-Easy adjust Carriage+effector
-axis stiffness mods
HE3D -600 delta
-Duet 0.8.5
-PanelDue
-DC42 Height probe
-RobotDigg metal components
Simplyfy3D
RS Design Spark CAD

Quote
bgkdavis
guess someone has to live there

And if your not in the land of the gods (Cairns) then I guess people have to live elsewhere as well

Where are you bg?

Brissy, maybe not quite the land of the gods

---

RepRapPro Mendel 3 Tricolour
RepRapPro Fisher
-Carbon Arms
-Easy adjust Carriage+effector
-axis stiffness mods
HE3D -600 delta
-Duet 0.8.5
-PanelDue
-DC42 Height probe
-RobotDigg metal components
Simplyfy3D
RS Design Spark CAD

another weekend and some more progress, the physical construction has got to a point where it now looks like a 3D printer







The dyzend hotend has arrived but still waiting on the E3D Titan extruder and a Duet 0.8.5..... start working on laying out wiring tomorrow.

I'm sure "royal mail tracked" from the UK ensures it goes on the slow boat, the mrs gets packages from the uk normal mail faster than the poor E3D Titan took to arrive..... but it did last night along with the Nema17 they had as an option. the Nema17 weighs in at 280g.
The Titan goes together pretty easy as long as you follow the instructions on the E3D wiki but one thing I'm not comfortable with is the quick release lever seems slightly loose on the motor shaft that leads to moving fractionally out of alignment, I've designed a additional fitting to better locate it but not yet printed to try.

This will end up in a flying extruder type setup but with 650mm arms (pending) I'm going to try something different.... pictures once I know it will work but aiming for 200mm of Bowden tube length. The 1300mm of internal height has created a couple of interesting possibilities and challenges

Phil

Did you go with the Steel Cored GT2 belt if so What size pulley have you gone For?

Reason I ask is that I put some of it on a printer and it lasted all of 2 days before it stretched and started jumping teeth.

It appears that it can't cope with tight bend radiuses and the Steel cores break internally and one of the teeth instead of being 2 mm pitch ended up more like 5

just a warning.

Doug

Everything decided to arrive in time for weekend.
Duet arrived Sat, thanks to Filastruder.
8mm ATP-5 Cast plate arrived Friday, thanks to CALM Aluminium, got a 610x900 offcut so have some spare
500mm 1200W heating pad arrived
found some 3mm ceramic paper for thermal insulation under the bed

Had some fun cutting out the plate to shape but some patience and lots of wd40 got it done. Stuck the heating pad on and did an informal test, absolutely no issue getting up to temperature actually it's to fast as the edges don't heat fast enough from transfer...... might upgrade to a 600mm heating pad in the future.

Now i'm firmly into unknown territory... this is my first reprap printer so all this firmware config setups is new and foreign, the hardest bit has been finding info on doing simple things.

Been taking this in baby steps, tested the tower motors first with the endstops and it was awesome to get things moving up and down.... now to get the rest of the wiring completed.

One thing I don't understand on the DWC web pages is the Machine Information tab under settings

There is an interesting piece about belts on Shapeoko site: [www.shapeoko.com]
So, it seems nothing could replace kevlar for belt reinforcment.
or , simply get larger belts or double them. RobotDigg sells wide and double pulleys for reasonable cost.

Quote
dougal1957
Phil

Did you go with the Steel Cored GT2 belt if so What size pulley have you gone For?

Reason I ask is that I put some of it on a printer and it lasted all of 2 days before it stretched and started jumping teeth.

It appears that it can't cope with tight bend radiuses and the Steel cores break internally and one of the teeth instead of being 2 mm pitch ended up more like 5

just a warning.

Doug

---

Pierre

- Safety [reprap.org]
- Embedded help system for Duet and RepRap Firmware [forums.reprap.org]
- Enclosed delta printers Lily [rouzeau.net] and Lily Big [rouzeau.net]
- OpenScad delta printer simulator [github.com]
- 3D printing on my site [www.rouzeau.net]

Quote
PRZ
There is an interesting piece about belts on Shapeoko site: [www.shapeoko.com]
So, it seems nothing could replace kevlar for belt reinforcment.
or , simply get larger belts or double them. RobotDigg sells wide and double pulleys for reasonable cost.

Quote
dougal1957
Phil

Did you go with the Steel Cored GT2 belt if so What size pulley have you gone For?

Reason I ask is that I put some of it on a printer and it lasted all of 2 days before it stretched and started jumping teeth.

It appears that it can't cope with tight bend radiuses and the Steel cores break internally and one of the teeth instead of being 2 mm pitch ended up more like 5

just a warning.

Doug

crap, don't know how i missed Doug's reply....... Yes went for steel reinforced 10mm wide GT2 on 20 teeth pullys and 20 tooth idlers.... i'll keep an eye on it.
Maybe Doug, you got a bad batch or lemon, I had a short length i was bending completely in half to test joiners and there was no obvious broken steel threads.

PRZ... yeah interesting little read.

Cheers
Phil

Think it is the repeated bending/straightening that works hardens the cores and makes them Brittle.

Point was just to make you aware.

Doug

Yes, belts dies from fatigue [en.wikipedia.org] and fatigue for composite materials is a VERY complex matter.

What I want to point with the shapeoko link is this sentence in 'tensile chords' paragraph:

Quote

Steel cords have higher tensile stiffness, but can't be bent as tightly so they may require larger-diameter pulleys and idlers.

Quote
dougal1957
Think it is the repeated bending/straightening that works hardens the cores and makes them Brittle.

Point was just to make you aware.

Doug

---

Pierre

- Safety [reprap.org]
- Embedded help system for Duet and RepRap Firmware [forums.reprap.org]
- Enclosed delta printers Lily [rouzeau.net] and Lily Big [rouzeau.net]
- OpenScad delta printer simulator [github.com]
- 3D printing on my site [www.rouzeau.net]

Exactly What we found Pierre tho we had them on 16 tooth pulley think the same would have happened with 20 and not as much so with 36's but think it would still happen

Quote
aussiephil
One thing I don't understand on the DWC web pages is the Machine Information tab under settings

You mean the Machine Properties tab? It shows you the values that you current have set for maximum accelerations, speeds etc. which will be as you have them configured in config.g unless you have amended them since the Duet was reset, or the firmware defaults if you did not configure those items. And it shows the endstop sensor states.

---

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
dc42

Quote
aussiephil
One thing I don't understand on the DWC web pages is the Machine Information tab under settings

You mean the Machine Properties tab? It shows you the values that you current have set for maximum accelerations, speeds etc. which will be as you have them configured in config.g unless you have amended them since the Duet was reset, or the firmware defaults if you did not configure those items. And it shows the endstop sensor states.

yeah that's the one I mean Ta

I'd sort of got half way down that road after I changed the settings for the motor currents for the N23 motors and seen the change reflected in this tab. It's one of the few tab's/forms that doesn't seem to be documented anywhere.

Might throw a feature request at Chris to see if the associated g-code's code be included in headings to assist people understanding which code to use to adjust things.

Cheers

ALIVE and Printing ...... happy and relieved

As it not yet enclosed and it's winter time here I've started with some PLA

First thing was a simple square 150mm per side, result came out at 150.65mm each way, close enough for today


Next i grabbed a bowl from thingiverse ...[www.thingiverse.com]
scaled it up by 130% and sliced it with S3D... took a few goes to dial in core settings but once I got it stuck to the bed all was good.


About 1/4 done


And finished item, the blue tape is 50mm wide strips to give an idea of size


Bed was set to 65c and being a 240v heater it was good to check the SSR ran cold for the 3hour print.


Slicer was set for 150mm/sec but doubt it got close, the frame will benefit from the enclosure bracing but the print isn't showing any obvious movement or vibration artifacts