Author Topic: 3D Printer yet?  (Read 66930 times)

0 Members and 1 Guest are viewing this topic.

Offline metrologist

  • Super Contributor
  • ***
  • Posts: 1834
  • Country: 00
3D Printer yet?
« on: September 05, 2017, 02:04:42 am »
I contracted a 3D illness this weekend and was watching videos covering some popular models, such as CR-10 and Tevo Little Monster. Are they worth considering yet?

The CR-10 almost always has good reviews, the Tevo was a bit mixed, but I kind of like the build of that one.

Any thoughts or suggestions? It's not something for which I have a direct need, just an interest, and it would mostly be for functional / somewhat structural parts, to complement my metal machine shop.

And to add, I really have no insight into the nuances of 3D printing, such as the types of heads, software workflows, etc. - just what I gleaned from an afternoon on youtube...
« Last Edit: September 05, 2017, 02:07:56 am by metrologist »
 

Offline Rerouter

  • Super Contributor
  • ***
  • Posts: 4616
  • Country: au
  • Question Everything... Except This Statement
Re: 3D Printer yet?
« Reply #1 on: September 05, 2017, 03:45:16 am »
Cant say anything about the models you suggested as i've never seen them

Main points:
Set aside a few hours after you have it set up and properly calibrate / level the thing, auto-leveling is a bit of a crutch, (I have a G2S Pro but would only recommend it to machinists willing to length match the diagonal rods and resurface the build plate)

Your build plate should be rigid, if its mounted on springs, ditch them and make it a rigid mount, otherwise the leveling will change 5 times a day

Any adjustment screws for endstops should have a locking nut to make sure they cannot move, these things jerk and vibrate all over the place.

Printers with longer "Bowden" tubes, (The tube that feeds the filament) need the larger filament rolls, those hand sized 500g rolls will curl too much for the motors to handle

The retract length is very easy to find, with it cold and filament stuck in print head, press the filament release, push the filament down the tube lightly, mark it against the top of the tube, then tug it and measure the difference, this is your exact retraction

Each filament, even different colours from the same manufacturer will have slightly different working temperatures

They are slow if your aiming for bigger than your hand.

For PLA, uniform cooling of the printed material makes everything better.


To clarify on the springs and locking nuts, I have on multiple occasions thrown my cheap chinese delta in the car to drive around to someone elses house, plugged it in, and it just works
« Last Edit: September 05, 2017, 03:48:57 am by Rerouter »
 
The following users thanked this post: Synthtech

Offline sokoloff

  • Super Contributor
  • ***
  • Posts: 1398
  • Country: us
Re: 3D Printer yet?
« Reply #2 on: September 05, 2017, 11:54:43 am »
Set aside a few hours after you have it set up and properly calibrate / level the thing, auto-leveling is a bit of a crutch,
I strongly agree with this point (and the rest of @Rerouter's post), but I'd modify it slightly to say:
Get the printer, get it roughly setup, and screw around with it for a few weekends. Print some crap. Have fun.

Then print a dial indicator holder for your particular printer, buy a dial indicator, and go through a detailed setup and calibration process. Plan to spend the better part of a full day doing it.

First use the dial indicator to tram the bed and get it precisely square to the X-Y plane. You can certainly get it within 0.002", but can probably get it within 0.001". Anything inside of 0.004" (0.1mm) will produce "OK" results, but the better you can get it trammed, the less aggravation you'll have later. Tram the bed with the machine at operating temperature (including a hot hotplate if you have one); be careful.

I used something like this, this, this, this, and something like this guide (though that's not the exact guide I remember using) and this guide (that one I did use). (None of those are affiliate links or anything that I'm connected to.)

Print the complex test object above before you start and then again when you're done to get a sense of how much improvement you were able to achieve.

When printing, use skirt always. I print ABS directly on clean Kapton tape (usually without any or with very little ABS/acetone slurry).
 

Offline Rerouter

  • Super Contributor
  • ***
  • Posts: 4616
  • Country: au
  • Question Everything... Except This Statement
Re: 3D Printer yet?
« Reply #3 on: September 05, 2017, 12:57:13 pm »
A dial indicator is a little overkill in my books, but be aware its a mechanical system. so tolerances will show you up if you don't account for them.

A fair bit of this is in relation to Delta Printers, but the ascpects overlap.

So as a simple start, a commercial kit or printer will generally not have an error in the angle of the vertical rods, (120 degrees), Its hard to measure and the influence from it is tiny. More likely your rods may not be quite parallel to each other, this causes binding or resistance in the carriages as they move up and down. which causes failures that may be dependent on temperate or minute changes.

Next in the chain is the carriages that travel up and down the vertical rods, depending on the bearings used they can rock side to side, in or out, etc, for a number of these, you can bias the bearing holders to reduce this motion, It is a source of backlash, and sadly most devices don't place the pivot for the diagonal rods at the center of rotation of the carriages, this alone would mostly eliminate it. you may see modders making carriages with more than 2 bearings to remove it, but biasing accomplishes the same task

Ok moving on the diagonal rods, My cheap choice of printer has had the majority of people recieve different length rods, due to the geometry of a delta if they are not very similar in length its impossible to make its travel level, a quick way to see if this is the case without disassembling a delta is to have it move along the A,B and C axis's of travel, the print head should not rotate at all. These rods are also where a number of people have tired to hunt down backlash, generally by rubber banding them, where in reality there issue is generally the metal pieces that attach to the sleeve bearing are not the right length and just need a nick of a file to bring rigid.

And finally all that's left in the middle is the print head plate. the lower the mass here, the less backlash and overshoot on fast direction changes your likely to see, dont go crazy, but lower weight here can mean a faster average print speed without issues like speed wobble as the motion rings out for a few mm past a 90 degree corner. Generally I havent seen things go wrong here, but a metal piece will last far longer than plastic as the hot end will deform it over time.


Ok so moving on to calibration. Delta's are a little hard to visualize at first glance, its part of what makes the math so weird, but in general as long as the build area is dead flat, and secured rigidly, it being perpendicular to the rods is not so critical, 2-3mm out of plane to the vertical rods can be calibrated out just by the end stops.

Ok, so first up, a Delta's true axis's of motion are A, B and C, towards and away from each tower, there may be a Y axis or and X axis depending on your machine but there is never both, 1 is just calculated. as such calibrating on X and Y axis only hides a lot of the information the movement is trying to tell you.

The first thing I adjust on a delta is its tramming per axis, You move it from one end of a towers axis and back again, noting which end it was out of tram, if it was low towards the tower, you want the end stop position higher, and vice verse, you will likely have to run through this step on each axis a few times in a circle, as it does slightly effect the other axis's as you tram one, but it does converge pretty quickly,

Next up is the Delta Radius, The math to convert a delta's radius based motion to XYZ is based upon an assumed radius of motion, If this radius is too high, the print head will raise towards the center of the build area, and fall towards the outside, and vice versa, most open source printer controllers (marlin or repeater firmware) let you correct this, generally saved to eeprom or by uploading a revised program over USB

And finally is build volume height, rather than touch your carefully adjusted end stops, instead lock them down and just tell the printer its taller or shorter to raise or lower the nozzle to the surface.

Now at this point i would always print a filled 1 layer high circle as a confirmation, generally by eye, looking at how translucent a printed piece is you can spot extremely tiny errors, on the level of a few microns, as the amount of smoosh between adjacent lines changes. this allows for some final small tweaking in.

At this point you should be ready to print something to tolerance, PLA loves cooling, ABS loves heating, for pla get some painters tape and a UHU glue stick, smear a very thin layer of the glue over the tape and you will be set, I've done well over 200 prints without applying new glue or changing the tape (I will eventually need to change it, its starting to discolour) For ABS, go with Kapton tape, a mist of Acetone on the build plate a minute or 2 before printing generally gets the level of adhesion i need (trace amounts of abs still embedded on kapton)

Things to be aware of, When you first run filament through a hot end, it will come running out at you, same for when it heats up to temp the expansion will cause some to shoot out the hot end, this is normal, if you can hear it sizzling, its either quite moist (humidity) or your running it too hot, for PLA humidity is generally fine, for ABS its more of a pain in interlayer bonding, so those rolls should be stored with a desiccant if your not using it for more than 2 weeks,

You will through a little bit of trial and error stumble upon the correct speed and temp for a given filament, e.g. the PLA i use reguarly, the white is 217C for speeds up to 50mm/s ramping up to 230C if i wanted to get to 85mm/s (the heat needs to fully melt the center of the filament), while the Black PLA i use, melts just fine at 182C, but I cannot run it faster than 30mm/s without crazy stringing, In both cases it relates to viscosity, but there will generally be a sweet spot that works best for you, both these filaments came shipped as (195C), but its never exact in my experiences.
 

Offline thm_w

  • Super Contributor
  • ***
  • Posts: 2141
  • Country: ca
Re: 3D Printer yet?
« Reply #4 on: September 05, 2017, 09:14:30 pm »
You don't need a dial indicator as the tevo has a bltouch (a switch that can probe the bed, to calibrate most aspects of the unit).

But don't get a delta unless you are willing to put the work in, and treat it as a bit of a hobby. If you only care about how cool it looks (I felt the same way), and its within your budget, then get it.
If you want minimal screwing around, get something like a prusa i3 mk2 (looks similar to the CR-10). Although that his a kit as well, it should go together simpler, and less chance of QA issues.
 

Offline metrologist

  • Super Contributor
  • ***
  • Posts: 1834
  • Country: 00
Re: 3D Printer yet?
« Reply #5 on: September 06, 2017, 02:26:17 am »
Thanks for all the detail. I'm still back here at the pondering stage and working through which style (Cartesian vs Delta) I'd investigate further.

The lion's share of what I see coming off of the the inexpensive printers does not interest me, but then I come across a few videos where folks produce something like a workable nylon gear and other somewhat structural ABS parts. I saw a review of the Tevo by both RCLifeON and GreatScott with drastically different results, so then I wonder how much is dependent on the operator and setup vs just getting lucky once in a while?

From what I gather, a Delta style printer is more finicky and suffers some kind of "salmon skin" effect, but typically offers more printing volume at significantly increased speed. The Tevo also supposedly can print all of the common filaments and has a hotter bed than many of the inexpensive Cartesian models, but i do not necessarily need it to be the cheapest option.

I seem to have gotten caught up in the maker type crowd and many of the reviews come from donated machines, so the users may have limited insight or otherwise biased. I'm just amazed at how many different makes and manufacturers there are now.

What about the different head/nozzle designs? I saw one product that had electronic circuit or "smart" nozzles. Reminded me of HP smart ink heads and cartridges. Anyway, there are probably some basic elements that are to be avoided and some that would be desired, and worth paying more to have.
 

Offline Muttley Snickers

  • Supporter
  • ****
  • Posts: 2117
  • Country: au
Re: 3D Printer yet?
« Reply #6 on: September 06, 2017, 09:28:45 am »
I'm yet to be afflicted by the bug and have enough on my plate already with projects and other stuff to finish first, anyway I watched a video yesterday  where Keith Fenner assembled and had a play with a 3D printer which was given to him by Bang Good, the video is a bit long winded at an hour and three quarters but I don't mind Keith so I watched it all through.

I'm not up to speed on these to make any real judgement but from what I saw they do appear to be somewhat flimsy, others will know whether these types of machines are any good or worth the effort and I expect that Keith will tell it like it is after he becomes more familiar with these products.

Keith Fenner 3D Printer
 

Offline Rerouter

  • Super Contributor
  • ***
  • Posts: 4616
  • Country: au
  • Question Everything... Except This Statement
Re: 3D Printer yet?
« Reply #7 on: September 06, 2017, 01:03:10 pm »
I have been using mine for engineering level stuff, PLA is stupidly strong when you get above 3mm wall thickness's, oddly 95% infil is much stronger than 100% as it can bend a lot more before permanent deformation,

Things i have designed and printed

18,800RPM 1.8L wine bottle radial centrifuge (wall thickness of the plastic was 5.1mm, any less and it would shatter from a speed wobble), estimated acceleration was in the ballpark of 20,000G's

Screw Clamps for science glassware

Replacement Gears for Paper Shredder (This was mostly a challenge to learn my CAD tools, nothing like inclined curved teeth to confuse a newbie)

Various Test Enclosures.

High power DC motor Mounting clamps, so i can use a commonly available motor and bolt it in place.

95% of a quadcopters frame, Every time i broke something, i just modeled it up, printed out a new one and was flying the next day. (also a few sacrificial bits of armour)




Most delta's without some level of cross bracing will wobble a little up the top, but unless your printing something quite tall it generally does not effect the dimensions.
 

Offline jfr

  • Contributor
  • Posts: 5
  • Country: us
Re: 3D Printer yet?
« Reply #8 on: September 06, 2017, 03:32:46 pm »
After watching some reviews I finally got the CR-10. I've been watching the printers off and on for a while and finally decided to bite the bullet.

It's a pretty decent machine. I need want one to do some quick and dirty prototyping and parts generation. I've since realised that some of the 'issues' people have had with 3D printers are them being overly picky. These sub $500 machines have better output than the "you need special permission" machines we had in college in the early 2000s. Some of the reviewers want a replicator.

The self leveling is a bit overkill IMHO. I got some feeler gauges and balanced the 4 corners and replaced the warped glass plate with a mirror tile.

One of the biggest selling points was that it was already mostly assembled. I had a print going in under an hour. While I sometimes enjoy mucking around with electronics and DIY projects I wanted a "print me this thing" device and for that the CR-10 is perfect. After some minimal configuration I printed a near perfect benchy: http://www.3dbenchy.com/ I'll usually run a build a day. One off toys for my son, RaspPi cases, Ardunio Cases, etc. Mostly stuff I find on thingiverse.

There are quite a few questionable design decisions and home made improvements that the users have found. The facebook group is fairly active to help. I'm probably going to knock off the design and make my brother one for Christmas rolling in the build improvements.
 

Offline metrologist

  • Super Contributor
  • ***
  • Posts: 1834
  • Country: 00
Re: 3D Printer yet?
« Reply #9 on: September 06, 2017, 07:59:13 pm »
Muttley, that's funny you found Fenner's video. I skimmed the first part of it and then went off looking for info on that model, and ended up finding RCLifeON's review- where he said the CR-10 was better. If the code works it would only be ~$10 more for it too, but I would not mind a build project. I also found the3dprintingnerd had some videos about the Tevo delta and succumbed to an hour+ live stream for community help - contrast that with RCLifeON's review of the Tevo (and what's with the stepper motor dangling in the air over the head?).









a point by volume





Then there is the Makers Muse



Moer?
 

Offline branadic

  • Super Contributor
  • ***
  • Posts: 1657
  • Country: de
Re: 3D Printer yet?
« Reply #10 on: July 21, 2018, 12:11:55 pm »
Hi,

I know this thread is somewhat old, but it's a good place to talk about Anycubic Photon. We brought one of this 3D printers, that is currently running at around 450€ on ebay, just for testing if this is any good.
We do have a Prusa FDM printer for mounting tools, prototype cases and such.We also do have a Prodways DLP printer for more advanced stuff, with some high performance material, that we use for injection mold inserts, 3D substrates where we attach tracks to realize 3D circuits and novel sensors. So we are used to handle DLP printed parts and messing with IPA but also familiar with the smell of the resins, so the 3D printing lab does have air ventilation etc.
And now we do have this really amazing bit of kit. I don't want to make any promotion, but this is a wonderful addition to what we already have at hand. Instead of printing avatars and similar sort of stuff this is a wonderful, precise and fast way to get specific prototype cases, mounting tools, holders of very good quality instead of sausage printers, even though you can get ceramic filaments, that can be sintered afterwards. The only drawback is the somewhat poor sclicer software, with it's poor capabilities of auto placing support structures.

Someone over here who uses Anycubic Photon for electronic developement to share experience and knowledge?

-branadic-
Metrology Meeting 2020 is canceled. Looking forward for MM2021
 

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 5179
  • Country: au
  • Toys so very many Toys.
Re: 3D Printer yet?
« Reply #11 on: July 22, 2018, 04:43:08 am »
Hi,

very nice selection of Printers   8)

as my recent acquisition CR-10S gets in the groove maybe it is time for either a dedicated thread on 3D printers and using them for Techie (non skull and statues  ::) ) uses? I got mine for Cases, mounts and similar uses rather than decorative too.

The Resin Print Technology looks great for precision work but to messy for non continuous use yet IMO. I am sure you have done it but there is some really good info on the Anycubic on YouTube too.

First slightly complex print off my CR-10S - new fang fan mount. Slightly melty at 220C so a little lower temp now.
Coffee, Food, R/C and electronics nerd in no particular order. Also CNC wannabe, 3D printer and Laser Cutter Junkie and just don't mention my TEA addiction....
 

Online Monkeh

  • Super Contributor
  • ***
  • Posts: 6393
  • Country: gb
Re: 3D Printer yet?
« Reply #12 on: July 22, 2018, 12:39:36 pm »
I suspect your retractions are a little low.. Pesky bowden.
 
The following users thanked this post: beanflying

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 5179
  • Country: au
  • Toys so very many Toys.
Re: 3D Printer yet?
« Reply #13 on: July 22, 2018, 01:00:04 pm »
Lots to learn and variables to play with. The Fang works a treat with a noticeable improvement on a Test Benchy. Also much more visibility over the stock setup on the lower layers.

Working on top mounting the extruder and remote mounting the spools above that to straighten the bowden a little. The Braces are actually on the printer to stiffen the Z axis to help that work better along with taller prints.
Coffee, Food, R/C and electronics nerd in no particular order. Also CNC wannabe, 3D printer and Laser Cutter Junkie and just don't mention my TEA addiction....
 

Online NiHaoMike

  • Super Contributor
  • ***
  • Posts: 6236
  • Country: us
  • "Don't turn it on - Take it apart!"
    • Facebook Page
Re: 3D Printer yet?
« Reply #14 on: July 22, 2018, 03:15:33 pm »
as my recent acquisition CR-10S gets in the groove maybe it is time for either a dedicated thread on 3D printers and using them for Techie (non skull and statues  ::) ) uses? I got mine for Cases, mounts and similar uses rather than decorative too.
A forum for 3D printing and CNC would be a good idea. Who else agrees?
Cryptocurrency has taught me to love math and at the same time be baffled by it.

Cryptocurrency lesson 0: Altcoins and Bitcoin are not the same thing.
 
The following users thanked this post: CM800

Offline all_repair

  • Frequent Contributor
  • **
  • Posts: 640
Re: 3D Printer yet?
« Reply #15 on: July 22, 2018, 04:16:37 pm »
 Get a magnetic base so you can peel off the print easily.  You can paste your blue tape on the magentic base further to prolong their life.  I cut my thumb badly when removing a print that was stuck to the bed before I got the magnetic base.  The cut needed 7 stitches, cost me the price of a 3D printer.
 
The following users thanked this post: NiHaoMike

Online NiHaoMike

  • Super Contributor
  • ***
  • Posts: 6236
  • Country: us
  • "Don't turn it on - Take it apart!"
    • Facebook Page
Re: 3D Printer yet?
« Reply #16 on: July 22, 2018, 04:59:47 pm »
A magnetic build plate is standard with the Prusa MK2.5 and MK3. Not sure why other manufacturers like Creality aren't getting onboard with that. Maybe patents?
Cryptocurrency has taught me to love math and at the same time be baffled by it.

Cryptocurrency lesson 0: Altcoins and Bitcoin are not the same thing.
 

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 5179
  • Country: au
  • Toys so very many Toys.
Re: 3D Printer yet?
« Reply #17 on: July 22, 2018, 11:46:05 pm »
I thought the Prusa was Open Source? There are issues with 'most' magnets and elevated temperatures if you are going DIY and Spring Steel sheets will be a PITA to get in small quantities of the correct gauge.

I had a few test prints come unstuck so I went to tape as I have a stack of it around and it seems reliable. The Hairspray I got locally was rubbish and no one in town sells glu stick (small town issues). I will get away from Tape and look at other surfaces in time. Santa has promised me an Ender 3 so worst case I will have to wait a bit ;D

Seems I got out of bed to early the overnight print needs a little more cooking  :)
Coffee, Food, R/C and electronics nerd in no particular order. Also CNC wannabe, 3D printer and Laser Cutter Junkie and just don't mention my TEA addiction....
 

Online Mr. Scram

  • Super Contributor
  • ***
  • Posts: 9250
  • Country: 00
  • Display aficionado
Re: 3D Printer yet?
« Reply #18 on: July 23, 2018, 02:49:22 am »
Levelling the bed is something that will make you tear your hair out at first, but also something you'll quickly learn the knack of. Rather than lengthy levelling and relevelling, many people can even adjust things on the fly during the first layer. If you add a brim to your print you're set before the actual print starts.
 

Online NiHaoMike

  • Super Contributor
  • ***
  • Posts: 6236
  • Country: us
  • "Don't turn it on - Take it apart!"
    • Facebook Page
Re: 3D Printer yet?
« Reply #19 on: July 23, 2018, 03:16:55 am »
The MK3 auto levels when starting a print. Some other printers like the CR-10s can be upgraded to do the same.
Cryptocurrency has taught me to love math and at the same time be baffled by it.

Cryptocurrency lesson 0: Altcoins and Bitcoin are not the same thing.
 

Online Mr. Scram

  • Super Contributor
  • ***
  • Posts: 9250
  • Country: 00
  • Display aficionado
Re: 3D Printer yet?
« Reply #20 on: July 23, 2018, 03:26:25 am »
The MK3 auto levels when starting a print. Some other printers like the CR-10s can be upgraded to do the same.
You don't really need it.
 

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 5179
  • Country: au
  • Toys so very many Toys.
Re: 3D Printer yet?
« Reply #21 on: July 23, 2018, 03:50:42 am »
I did break out the Moore and Wright squares, Calipers, Dial indicators and levels before turning the power on partly as my printer arrived as a CR-10 with the later arrival of the upgrade 10S kit. I also fitted X & Y stepper dampers  :)

Plenty of loose wheels, belts and a mixed bag of screw tensions (or lack of  :palm: ) initially but starting square and level makes any CNC easier.

So Bed leveling didn't present to many issues. Auto bed leveling looks like a nice add on particularly if you are running the printer hard or running a bunch for light production.
Coffee, Food, R/C and electronics nerd in no particular order. Also CNC wannabe, 3D printer and Laser Cutter Junkie and just don't mention my TEA addiction....
 

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 5179
  • Country: au
  • Toys so very many Toys.
Re: 3D Printer yet?
« Reply #22 on: July 24, 2018, 03:06:00 am »
Nearly 17 Hours and 84% into a print - LEVEL SHIFT  |O

Pub O'Clock  :popcorn:
Coffee, Food, R/C and electronics nerd in no particular order. Also CNC wannabe, 3D printer and Laser Cutter Junkie and just don't mention my TEA addiction....
 

Online Mr. Scram

  • Super Contributor
  • ***
  • Posts: 9250
  • Country: 00
  • Display aficionado
Re: 3D Printer yet?
« Reply #23 on: July 24, 2018, 11:02:40 am »
Nearly 17 Hours and 84% into a print - LEVEL SHIFT  |O

Pub O'Clock  :popcorn:
That's the proper 3d printing experience.
 

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 5179
  • Country: au
  • Toys so very many Toys.
Re: 3D Printer yet?
« Reply #24 on: July 24, 2018, 11:56:17 am »
Been to the big smoke and got some glue stick today so I am running some tests back on glass only with a small brim - so far so good  :)

After I dropped the support materials off the failure I think it while ugly will do the job (top brackets for the frame brace) and seems stiff enough. I will reprint it sometime later most likely.
Coffee, Food, R/C and electronics nerd in no particular order. Also CNC wannabe, 3D printer and Laser Cutter Junkie and just don't mention my TEA addiction....
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf