What would you build if you were starting again now?

deckingman

@opentoideas said in What would you build if you were starting again now?:

...............This led me to ask the question why all these new super complex machines?............................

Possibly because of laziness or incompetence, but let's be generous and say it's simply a lack of understanding. Multiple motors on one or more axes has been mentioned often in this thread. Why would one want to add that complexity? In the case of a Z axis, it's because people think it is somehow difficult to build a bed which is flat, level and stays that way. So rather than building it properly with a single motor driving multiple screws, they add a motor to each screw so that they can use the firmware to make it level. That just adds a level of complexity for no gain. In fact it makes matters worse because every time the power is cycled, the motors jump by up to 4 steps relative to each other so that firmware levelling process has to be done every time the printer is turned on and off. Similarly using multiple motors to drive an X or Y gantry is because people can't figure out how to stop the gantry twisting. So they add a motor to each end rather than fix the problem mechanically.

Or maybe it's just bad design. People build machines or start with basic kit, see what problems there are, then add more parts to cure the problems instead of going back to basics and fixing the fundamental design flaws.

Whatever route you choose, take your time, build it properly, build it rigid, use good quality parts and materials. Those things are far more important than what type of kinematics to use.

In the final analysis, Cartesian, CoreXY, Delta and derivatives thereof are all capable of producing good quality parts. Arguably, it is the hot end and extrusion system which will determine the print quality and speed, so how that hot end is moved around in space is somewhat irrelevant.

opentoideas

@deckingman said in What would you build if you were starting again now?:

Possibly because of laziness or incompetence, but let's be generous and say it's simply a lack of understanding. Multiple motors on one or more axes has been mentioned often in this thread. Why would one want to add that complexity? In the case of a Z axis, it's because people think it is somehow difficult to build a bed which is flat, level and stays that way. So rather than building it properly with a single motor driving multiple screws, they add a motor to each screw so that they can use the firmware to make it level. That just adds a level of complexity for no gain. In fact it makes matters worse because every time the power is cycled, the motors jump by up to 4 steps relative to each other so that firmware levelling process has to be done every time the printer is turned on and off. Similarly using multiple motors to drive an X or Y gantry is because people can't figure out how to stop the gantry twisting. So they add a motor to each end rather than fix the problem mechanically.

yup I resemble that remark

the first "modification" I made and the biggest continuing pita. now I know slightly more the error is obvious but it seemed like a good idea at the time

fcwilt

@opentoideas said in What would you build if you were starting again now?:

@fcwilt ok perhaps not super complex but mechanically a delta is almost as simple as it gets and I suspect as a result needs to be a far higher tollerance to ensure everything works. Kits from china are less likely to be as high a tollerance as needed and would make the setup challenging but once done or corrected its not got much to go wrong or out of allignment.

With everything at right angles I can see the box design being easier to get correct but there are a lot of moving parts all wearing differently so tweaking and maintenance may be a long term issue.

Delta's are indeed rather elegant which is why I started with them.

And clearly lots of folks can get them setup and working just fine.

I just found them rather frustrating. The FT5 was so simple to get working. I had spent months on the delta's trying to get them to work the way I wanted. I got what I wanted from the FT5 in a week.

Maybe someday I will try a large delta but for now I am having fun exploring different kinds of "Cartesian" printers.

opentoideas

I think 3D printing and frustration go hand in hand.

I started with my cartesian bed slinger and also found the first months a frustrating and unsatisfying experience however eventually something must have sunk in as it all started coming together.

For this current job I finally ran out of the PETG I was printing with from the start so figured I might as well use up some of the PLA I had kicking about..... que another frustrating couple of days dialling in to a different although alledgedly "easy" material

Fortunately the frustration tends to be short lived and the satisfaction of a good print keeps on rewarding

While speed isnt the ultimate aim I guess I would want to do better. At the moment while I can push 150-200mm/s I only use that for very rough tests and for any actual production part for use I need to be at 50-100mm/s depending on the part.

While it always feels slow what are realistic speeds for a reasonable finish with a well designed modern printer? I am guessing there isnt a huge improvement to be gained possibly double?

zapta

@pixelpieper said in What would you build if you were starting again now?:

@zapta I run this very combination together with a 1LC V1.1 toolboard, works extremely well.

@pixelpieper, is the toolboard installed on the moving printing head? What is the motivation, simplifying the wiring? Can you post a picture?

I can't imagine installation of the toolboard on the moving head without destroying the aesthetic of the Voron V2.4.

pixelpieper

@zapta Simplifying the wiring and getting the accelerometer onto the toolhead. It is a bit on the large side and I would totally dig a miniature version of the 1LC, but it works quite well as is.

DIY-O-Sphere

@pixelpieper said in What would you build if you were starting again now?:

I would totally dig a miniature version

https://hackaday.io/project/174429-huvud-a-3d-printer-tool-head-controller-board

zapta

@pixelpieper, looks much nicer than I expected. You replaced the original connector cover.

Yes, a smaller one would be nice. A Voron version, with only the necessary connectors and components on both sides.

pixelpieper

@diy-o-sphere I know, but not rrf compatible and the newest version with accelerometer is as unobtainable as the atsamc21 is which is driving the 1LC, otherwise I would be tempted to make a shrunken down 1LC myself.

pixelpieper

@zapta the great thing with the way this is now mounted is that I was able to map extrusion and retraction onto the two toolboard buttons which is great for loading filament.

dc42

@pixelpieper said in What would you build if you were starting again now?:

@diy-o-sphere I know, but not rrf compatible and the newest version with accelerometer is as unobtainable as the atsamc21 is which is driving the 1LC, otherwise I would be tempted to make a shrunken down 1LC myself.

The tool board layout is already tight. To make it smaller we could have to remove some functionality. The board that @DIY-O-Sphere linked to doesn't support a Z probe, or a docking switch, or fans with tachos, or 4-wire PWM fans, or 12V fans when using 24V VIN, or a filament monitor. I also suspect that the buck regulator would fail CE tests for EMI.

DIY-O-Sphere

@dc42
I know that's comparing apples and pears. But the form factor is cool and like pixelpiper said reduce functions.

fcwilt

@opentoideas said in What would you build if you were starting again now?:

While it always feels slow what are realistic speeds for a reasonable finish with a well designed modern printer? I am guessing there isnt a huge improvement to be gained possibly double?

I haven't attempted to break any speed records.

My default speed is 60 or 90 mm/s depending on what I am printing. I can do 120 but print quality suffers a bit and I'm kind of OC when it comes to print quality.

I've read the factors such as path length coupled with acceleration can get in the way of truly consistent high speeds like the 400mm/s reports you hear from time to time.

When I have configured my printer these higher speeds it begins to make noises I don't like.

Frederick

opentoideas

@fcwilt quality is so subjective as everybody has different aspects of quality and what is acceptable.

For the type of things I tend to print dimensional accuracy is probably most important as parts are often interlocking the current ones having a sliding friction fit rail assembly so it either works or not.

While it is printing at 85mm/s I am less concerned over surface defects as long as the parts fit but surface defects at the points of contact are a problem. Part strength and layer adhesion are more important.

Sounds like my old bed slinger isnt doing too bad though

giostark

@alankilian said in What would you build if you were starting again now?:

Speaking of deltas, (I have a SeeMeCNC Rostock Max V3.2 which uses a Duet2/Ethernet)

SeeMeCNC build a 300mm Delta for US$1,500 and a 500mm !!! Delta for US$4,500. Both use Duet.

You can see the warping even in the demonstration picture...

pixelpieper

@dc42 I am aware that it is already tight, but it is totally acceptable to reduce some functionality. An other option would be to have a stack of PCBs, combining a “digital” one with uC, driver, and CAN transceiver with a power board containing the regulators as well as the MOSFETs for fans and heater.

dc42

@pixelpieper said in What would you build if you were starting again now?:

@dc42 I am aware that it is already tight, but it is totally acceptable to reduce some functionality. An other option would be to have a stack of PCBs, combining a “digital” one with uC, driver, and CAN transceiver with a power board containing the regulators as well as the MOSFETs for fans and heater.

A stack wouldn't work on a E3D tool changer because there isn't room.

Basically, it's impossible to make a single board that meets all needs including CE certification and a desire for smaller size. As it stands, on a Voron the Duet 3 Tool Board provides everything needed, including support for the Z probe and an accelerometer, and provides options for a second temperature sensor for a Pinda-type probe and for fans with tachos.

fcwilt

@opentoideas said in What would you build if you were starting again now?:

@fcwilt quality is so subjective as everybody has different aspects of quality and what is acceptable.

For the type of things I tend to print dimensional accuracy is probably most important as parts are often interlocking the current ones having a sliding friction fit rail assembly so it either works or not.

With the rare exception of printing something in the "fun" category for family/friends everything I print are functional parts of one sort or another. So my requirements are likely quite similar to yours.

Frederick

MikeS

@ajdtreyd My rostock max v2 is laying on the floor with 60% of parts removed (also me an user from 2014). For the last month my Voron 2.4 have printed 8 hour a day and it's working great. I would never come back to a wooden delta anymore and i'm printing faster and with more acceleration now with a direct drive extruder than with the bowden one in the rostock. Things are going only to improve with the upcoming 3.4.
I'd like to build another delta but they need to have a really rigid frame to print reliably and also dimensional accuracy is not always so good, usually near the towers.

ajdtreyd

@mikes

Hehehe, yeah. My v2 sat unused in the corner for almost 2 years. In its stock form I don't think that printer found too many owners able to make it live up to the marketing claims. Like the 280mm (11 inches) diameter build area when the arms are only 270mm long. Their forums were full of complaints about print quality for anything more than 100mm from center. I guess my point is, don't judge all deltas by a really old model with poorly designed geometry and a pressboard (MDF) frame.
After a couple years of upgrading my knowledge and my delta, I'm printing dimensionally accurate parts with no trouble. Here's a test print I did after my latest upgrade (replacing the too flexible molded cheapskates with carriages I designed and printed).

I still needed to tune PA, used no input shaping and I used some old, loose PLA for the test print so its not as good as the printer can do. I had just watched Nero3DP's video "toasty is melting" during which he was asked what his typical print speeds and accels are. He displayed the speed/acceleration page from his SuperSlicer profile and so I used those settings to print the voron cube.

All this said, I would recommend to anyone who has a stock v2 or v3 (or even v4 ??) not bother upgrading unless they are into it for the learning. Contrary to my belief when I started the upgrade process, it's cheaper, easier and faster to just build a new printer. You can sell the old one to someone with an unusual appreciation of nostalgia!

Trey