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Post by atgordon on Dec 31, 2019 2:37:53 GMT
I have followed Roger's use of 3D printing very closely, and realized that a lot of the jobs I have to create weird fixtures for could be simplified if I had a 3D printer. Simple place the part inside a rectangular body in F360 and subtract the part, and voila, a regular vice compatible clamp. I was waiting for the price to fall for the Prusa kits (still in the $800 range), and just before Xmas saw that I could purchase a TronXY P802MA (an i3 clone) for $87.45 delivered for free ... a Xmas present to me! Plus it offers a 220x220x240 build space, heated bed and self-leveling sensor. (added a UK purchase link in response to a PM ... NFI!) Instructions were a little lacking, but nothing that couldn't be worked out by anyone on this list. Getting the bed leveled and the nozzle at the right height was a pain ... however, some very good YT videos based on the Anet A8 (another clone with a larger user base I'd guess) showed how that could be done. Since then, I've been printing parts successfully for a few days. See below for a PETG (can be used at higher temps and is impervious to coolant) print for an improved Y-axis belt adjuster and a lathe fixture/clamp for a racing ball joint that I need to skim 6mm off the face (part of a anti-roll bar assembly that has ball joints and nylon bushings in place of the usual BL rubber crap stuff). Very pleased so far ...   The wheel in the center is threaded as is the plate with the 4 holes .. it prints the threads! Might not do 8BA, but I love the idea of printed threads (you might see whiskers on the threads and some other parts. A downside of using PETG, but they pull off easily with fingers or pliers in extreme cases! |
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dscott
Elder Statesman
Posts: 2,440
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Post by dscott on Jan 1, 2020 3:09:40 GMT
I still have a box of bits and keep looking at various ideas.
Of course I am going to it together myself.
When your wife or Girlfriend are out...
type in Naomi sexy cyborg wu into You tube and she will show you all you need to know about printers.
She has a huge following and yes they are extended before you ask!!!!!!
Chinese Girls are quite small. In one video Naomi prints a Bikini... Then wears it to a pool party.
YOU HAVE BEEN WARNED.
Happy new year in advance.
David and Lily.
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Post by Jo on Jan 1, 2020 8:41:55 GMT
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Post by Jo on Jan 1, 2020 13:24:58 GMT
Mine should be with me on Monday, as will one reel of PLA and a reel of ABS to learn with 
Jo
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Post by atgordon on Jan 1, 2020 15:46:14 GMT
Mine should be with me on Monday, as will one reel of PLA and a reel of ABS to learn with
Jo
Congrats! You'll enjoy the printer, once you get the paper off the perspex and get it assembled! (the paper removal takes ages) I have made some minor improvements to my printer, primarily adding a MOSFET card to the unit to relieve the main board of carrying the large current for the heated bed. Some useful tips on how to do that can be found in this video ( www.youtube.com/watch?v=ilHyXLVTmLg&t=810s ) ... the MOSFET bit is about half way through, so you have to watch the most tedious and unnecessarily complicated way to add a cork insulator to the heated bed ... I drew round my board with a pencil, cut the tile with a stanley knife, sprayed both with 3M adhesive and bingo, insulted bed! The one thing I would have done as I was assembling the kit was to add stops to the print head guide rods to allow an X-axis adjustable tensioner to work correctly (see the issue explained at 6:29 minutes in the following video, which has a lot of over engineered ideas which can be mostly ignored,apart from the stops - www.youtube.com/watch?v=G5XpvJxJVaQ I have also added a glass plate to the bed to make it easier to remove prints: this causes a problem since the leveling sensor can't detect the glass (not inductive!), so some G code tricks are needed ... see this really helpful video to see how it is done ( www.youtube.com/watch?v=pn1Jd1IiZOE) I would recommend adding an adjustable tensioner to the Y-axis. It is difficult to get the belt tight enough, and I have had some belt slippage already (I slowed down the feed rate in Cura to compensate until I get a tensioner printed). Lots of improvements, including the tensioner can be found here www.thingiverse.com/search?q=TRONXY+P802MA&dwh=485df29433bf040PS: The Anet A8 is physically very similar to the tronXY P802MA (although it appears to use a different control board), so a lot of the improvements and add-on's can be found under that model name as well. Have fun! |
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Post by Jo on Jan 1, 2020 17:57:48 GMT
Thanks, just now have to wait for it to arrive.
Jo
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Post by Jo on Jan 6, 2020 22:32:53 GMT
My cheap 3D printer has turned up. Nearly together but a connector was missing so have ordered one (take too long waiting for the Chinese to deliver one). I am not convinced by the 5mm plywood it is made from but there is nothing stopping me replacing the bits with Aluminium if I get bored. Likely to be a couple of days before I can print anything. Suggestions are welcome  Jo |
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Post by springcrocus on Jan 8, 2020 8:02:18 GMT
Likely to be a couple of days before I can print anything. Suggestions are welcome Jo Loco nameplates?  Regards, Steve |
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Post by Jo on Jan 9, 2020 18:42:40 GMT
Thanks Steve After a few modifications that I have been documenting over on MEM.. So far I have a 25mm cube Jo |
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Post by atgordon on Jan 10, 2020 0:31:40 GMT
Well done Jo, a couple of words of caution ...
This is a cheap, but very well equipped printer (not many low cost printers have auto-bed levelling). But the controller board has very limited memory, it also doesn't have a restart from a failed print. This is a royal pain.
For GBP 70, you get a pretty OK printer with great specs, and with a few well documented tweaks (look for TronXY P802M and Anet A8 which are largely physically similar -Anet has a different controller board), you get a pretty good printer.
I now have a lot of good prints, but only after greatly restricting print time to less than 8 hours. Over 8 hours, it is a crap shoot. And the Melzi 2 control board is so limited it doesn't have "restart print" feature! (a real downside)
I have an old Raspberry Pi 2b, which I plan to use with Octoprint hooked to the printer to see if it improves things. I'll report back in due course.
Roger's pitch for the Prusa unit makes sense if you want a good printer out of the box. The really low costs all have a downside, including the Ender 3, which offers more than the $85 TronXY (but no bed levelling), so they are all well short of the capability of a Prusa i3 mk3.
Will I pay out for the more expensive unit now? probably not. I'll try to add Octoprint (and maybe the with Klipper, if I can fathom how to use it) first, and if it will handle multiple-part, long run-time prints, I'll fine tune this unit to add a lot of the highly recommended upgrades. And I'd still be quids in.
I'd give this unit about a 5/10, and unless you're a gadgetter, I'd hold off getting one for now ...
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Post by atgordon on Jan 10, 2020 1:46:13 GMT
My cheap 3D printer has turned up. Nearly together but a connector was missing so have ordered one (take too long waiting for the Chinese to deliver one). I am not convinced by the 5mm plywood it is made from but there is nothing stopping me replacing the bits with Aluminium if I get bored. Likely to be a couple of days before I can print anything. Suggestions are welcome Jo Just saw this ... the US version is 7.2MM acrylic (and pretty good stuff too ... flat and no flaws) ... didn't realize that the UK version was plywood (not that the Acrylic is that rigid .. I'm running at 60mm/s to stop ghosting). |
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Post by Jo on Jan 10, 2020 8:41:35 GMT
My one now has 10mm Aluminium on the ends of the X axis, with threaded bars. This mod has seriously improved the rigidity.
Printing is ok... As I purchased it to make jigs for use in the workshop I am not fussed by the fact that the layers of plastic are not perfectly aligned.
Second print being attempted to see how it handles holes and curves. This one is scheduled for 5 hours...
Jo
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Post by atgordon on Jan 24, 2020 4:08:26 GMT
Since I started this thread, I thought I ought to give an update having lived with a cheap 3D printer for a few weeks ... Lesson 1: don't expect quality when you pay pennies not pounds. In fairness, I was trying to work out if I could really use/justify a 3D printer and was willing to spend $85 (GBP 68) to see. Lesson 2: Once you get the machine printing, you will spend a lot of time making parts that make it work better. Lesson 3: The 8-bit control board runs out of memory (or who knows what) on long print ... and stops mid-print (after 16 hours ... **@!#$). And this printer does not have a restart from where you left off function (a real PIA). Lesson 4: Expect to learn a lot about 3D printing ... I run a CNC shop (a retirement project that pays for beer, and thankfully not too busy now) and I found myself at the computer for many hours learning how to run 3D printers, and I discovered, its more of an art than a science when compared to CNC machining ... there aren't feed and speed tables and calculators out there ... there are guidelines, but everything is a variable, so it seems to a beginner like me that trial and error is the name of the game for each filament you use - please correct me if I am wrong!. I have now got the printer producing prints that are good quality in PLA and PETG, but it has taken a lot of time and mods, as you will see ... I placed supports on the Y axis ( I used 1/8" angle iron brackets at both ends) [you might seen that Jo did the same] ... you will also see the Y-axis tensioner download from thingiverse.com (what a great resource for 3D printer folks).  Next, improve the bed spring system with 4mm CSK bolts (not the 3mm supplied), meaty springs and nyloc nuts that don't undo when the printer runs like the original wing nuts ... I watched them rotate on the first test print!  Use Octoprint for all your printing ... the cheap Melzi 2.0 onboard controller is a very limited 8-bit board, so if you have a Rapberry Pi nearby, you can run the printer from that single board computer. I had an old RPi, but it didn't support wifi, so I had to purchase a RPi 3A+ ($23). Once you prepare an Octoprint image on your PC or Mac (on a SD card), the RPi will boot to Octoprint, and you are good to go. From then on , you can run the printer from your computer (or your smart phone), and it will drip-feed the g-code to the control board so no board related errors. This is a game changer if you buy a low cost system since the control software is so limited ... on the TronXY unit I bought, I can't even load or unload filament from the crap control panel!. This link will give you the info you need to setup Octoprint ... it worked like a dream for me.   Finally, I did replace the drive belts with higher quality ones (I went for the glass fibre steel cored ones .. hopefully no stretching). I mounted the entire printer on a 19mm plywood board and added printed clamps to the 8mm threaded rods ... not sure it made much of a difference but the prints I'm getting now are clean without any X or Y artifacts caused by shaking or axis vibration .. I also cut the print speed down to 50mm/sec, so that might have helped!  If you go down the cheap-arsed route, you will learn a lot, if you want to cut down on that time, go for an assembled Prusa 3+ unit which will give a fully functioning unit out of the box ... Keep at it, my cheap-arsed list companions, you will succeed in the end! |
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Post by simplyloco on Jan 24, 2020 10:09:33 GMT
SNIP If you go down the cheap-arsed route, you will learn a lot, if you want to cut down on that time, go for an assembled Prusa 3+ unit which will give a fully functioning unit out of the box ... Keep at it, my cheap-arsed list companions, you will succeed in the end!I'm Sooooo glad I'm not a cheap arse...  20190608_142337[1] by inkaboat, on Flickr |
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Post by Jo on Jan 24, 2020 18:37:13 GMT
[I'm Sooooo glad I'm not a cheap arse... href="https://flic.kr/p/2gaJVFJ"]20190608_142337[1] This is the way with technology: Start by trying a cheap lathe and later buy a reasonable one ( mine is a Hardinge HLV-H I named Mr Silky  ) Start buy buying a cheap 3D printer and see if there is any point see how useful it maybe before wasting money on something more expensive. Still working no this one ... Jo |
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Post by atgordon on Jan 27, 2020 0:36:52 GMT
This is the way with technology: Start by trying a cheap lathe and later buy a reasonable one ( mine is a Hardinge HLV-H I named Mr Silky ) Start buy buying a cheap 3D printer and see if there is any point see how useful it maybe before wasting money on something more expensive. Still working no this one ... Jo Your comment about lathes made me smile ... I did just that with my first lathe lathe ... purchased a cheap 7" lathe + vertical milling head! Complete piece of sh*t, that took some time to sell! Now very happy with my 14"x40" Chinese gearhead lathe. Incidentally, I looked around for a long time to see if I could find a good Hardinge lathe via Craigslist (a free online system used extensively in the US), but they are rarely cheap ... you are very fortunate to have such a fine piece of gear! You will smile when you hear that nearly got my hands on a really nice 1950's Monarch 10EE on sale for $1000 but someone got it before I could contact the seller (in 2006 when every machining business in Michigan was in the doldrums and many going bankrupt ... my 2006 purchased Chinese lathe cost $800 with a DRO and accessories!). About the only lathe that matches the Hardinge for build quality and accuracy, but a lot bigger. (I still have a online sales tracker looking for an EE just in case I can find a really good one for less that $5000!) |
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Post by atgordon on Mar 25, 2020 23:12:24 GMT
OK ... gave up with the TronXY, just too many issues and even with the Octoprint/Raspberry Pi combo (which is an amazing way of making a cheap printer produce long run-time prints). I looked at all the i3 models out there, including the very well respected Prusa i3 mkIII, and decided that the moving Y axis table was always going to be a limitation, particularly if printing large objects: the table weighs quite a few grams, and improved adjusting system with heavier M5 nuts and bolts, plus the insulation layer all added up, and when the table was moving quickly, it rocked the framework more than the X or Z movements. The Core-XY generation of printers do not move the table in the Y plane at all: the print head is moved in the X and Y axes, and the Z axis moves down as the layers increment. The printing inertia is constant and not affected by the mass of the item being built (as it is in the i3 models). The unit I went with also has a remote bowden cable/tube filament feed to the print head (the feed motor is mounted remotely on the back panel of the printer, not on the print head) and since the print head is now much lighter, the feed speeds can be increased since the print head inertia is reduced. I opted for a Flying Bear Ghost4S printer for $310 (absolutely no financial involvement apart from laying out the dosh to buy it!). It did need assembly, but that was largely assembling and aligning already pre-assembled parts. No step-by-step manual, but an OK Youtube sequence. I found it very simple to assemble, and anyone on this list will quickly workout how to ensure that the Z-axis rods are actually "aligned", something the video doesn't do to well! I'm happy with the machine so far (2 days of printing and not one issue!). I like the fact that I can very quickly enclose the unit with a door and a top hat and so print ABS and ABS+ easily. I understand that having an enclosure helps the printing of other materials too. The rigidity is good, and the noise level is very low. Here is the assembled machine at work ...  Smokebox door numbers for the Manor (the 8 was a test print) ...  The rear-mounted filament feed system  The 32-bit control system, which supports WiFi loading and printing (straight from Cura!) ... all touch screen and easy to use including loading and unloading of filament!  Video of the printer at work ....
youtu.be/Qamxb_gq4yw |
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Post by Roger on Apr 5, 2020 10:24:41 GMT
It's good to see you're up and running with a much better made printer. The touch screen and 32bit software is an improvement on the Prusa. The new mini Prusa has 32 bit, and I suspect that will be offered as an upgrade at some point. Wifi would be good without having to resort to a Raspberry Pi.
I've never heard of any issues with the split axis design though. I think you might be over estimating the effect of the weight of a large print. I've certainly never seen any printing issues on mine. In reality, I think you'd be very unlikely to print something heavy enough to make a different.
I have modified my prusa by the addition of two sturdy aluminium side plates though. That's because I'm making an enclosure, and that means removing the power supply which acts as a stiffener on one side. It would be too flexible without that, so it made sense to add one to both sides. You don't want any of the electronics inside a heated enclosure.
Anyway, I look forward to seeing what you make. These tools are amazing, I've used mine a lot.
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