billbedford Posted March 26, 2021 Share Posted March 26, 2021 Looking closely at the photos, it looks like the layers need the apex are deeper than those just below them. Are you using adaptive layering, or something similar? Link to post Share on other sites More sharing options...
MikeTrice Posted March 26, 2021 Author Share Posted March 26, 2021 Rob Apologies, I had not realised that the roof was solid. Yes you need to reduce the exposures when using clear resin, however my experience of printing clear is limited. Those distortions do look very odd and I cannot offer an explanation. If it was me trying to print this I would hollow the model and raise it above the build plate and rotate is some 70-80 degrees. I am assuming here that you have a side that can be placed nearest the build plate and have supports going to it. There will be some distortion where the feeds attach but hopefully they can be sanded smooth. You would then need some supports to keep the model steady during printing. If it helps feel free to PM me the stl and I will do a sample chitubox file and return. Link to post Share on other sites More sharing options...
rholgateau Posted March 27, 2021 Share Posted March 27, 2021 Bill, Yes, the (strange) effect is as if the layer heights had increased near the ridge line. But I haven't knowingly done this - and I didn't know that it could be done on a Photon S. I'm running some further tests : one ridge rather than 3 - is the overall area of the print causing some excess load on the Z axis? changing the overall height, to see if the effect is at a constant Z height, or a constant height relative to the ridge. Maybe I have a binding on the vertical drive at that point? and anything else I can think of. I'll report back, in case anyone is interested... Rob 1 Link to post Share on other sites More sharing options...
RMweb Gold simonmcp Posted March 27, 2021 RMweb Gold Share Posted March 27, 2021 I don't know if Chitubox has 'Adaptive layers' in as an option as if it does that would give that effect. Link to post Share on other sites More sharing options...
RMweb Premium njee20 Posted March 27, 2021 RMweb Premium Share Posted March 27, 2021 Nope, it can be done, but definitely not by accident. I wonder if it’s something to do with the resin pooling at the apex on the last few layers, almost like an inverse elephant’s foot. I can’t quite get my head around that though, as it should be completely displaced by the build plate. I wonder if a higher lift height and/or slower lift speed may help, allowing the excess resin to drip off. Link to post Share on other sites More sharing options...
tebee Posted March 27, 2021 Share Posted March 27, 2021 My guess is it's not actually pooling but something similar, because it's a solid mass you can't get pooling a such. It's a transparent resin, so you need reduce the exposure due to UV bleed through from the layers below. But a side effect of this is that the last few layers are not exposed quite enough as there are no layers below. Coupled with the area being exposed reducing each layer as we near the apex, those last few layers will be underexposed, more liquid and sag a little under their own weight, before being squashed outward when the build plate returns to the bottom. As the build plate rises after the print has finished, those layers will sag again giving layers of increased thickness.. I'd solve this by making it hollow, angling it front to back by 30 degrees and putting supports along the valleys and edges only Link to post Share on other sites More sharing options...
billbedford Posted March 27, 2021 Share Posted March 27, 2021 That doesn't explain why the last few layers are thicker than the rest of the build. I think along the lines of maybe the OP should clean and re-grease the lead screw, especially at the bottom end. Link to post Share on other sites More sharing options...
tebee Posted March 28, 2021 Share Posted March 28, 2021 5 hours ago, billbedford said: That doesn't explain why the last few layers are thicker than the rest of the build. ... because it's semi-liquid it's getting squished outward in the build plates downward stroke, you get a little extra resin traped each time which then gets part cured. Eventually this extra resin slumps downward under gravity, forming the too thick layers. Link to post Share on other sites More sharing options...
rholgateau Posted March 28, 2021 Share Posted March 28, 2021 Hmmm - further usefule suggestions there, guys? Tebee: you are suggesting that maybe it slumps - presumably, after the printing has finished? But I'm a bit surprised that it happens along such a clear line... I've tried some further controlled tests with details removed in the CAD file, so that it is just a "prism" Vertical height of object adjusted between runs solely by extruding the base (i.e. roof angle is constant) Settings are: Photon S, latest firmware, Chitubox v1.8.1, 4x80s base layers, 0.020layers at 6s exposure, list 6mm @60mm/min, Bottom tolerance compensation -0.7mm. Exposure is based on a Photonsters/RERF print with this resin, showing 5s is barely adhering to the base layers, 6s is best for engraved detail, and 11s best for raised detail. (I have roughly sprayed grey primer over the clear resin, to make the results more visible) Apart from that, the only variation between runs is the resin: I topped up between some runs, and didn't on others. Could the resin be settling in the VAT, with different print characteristics at the bottom if it hasn't been stirred?? I have tried three comparative runs: Print 1 and Print 2 are identical, except that #2 have three identical units. I was looking to see if the "point of inflection was the same on both runs, which might suggest a mechanical problem at a particular vertical height. Unfortunately, Print 2 showed the symptom occurring at a different height Print 2 and 3 are identical, except that #3 has the left unit 1mm taller, and the central unit 1mm lower. Print 3 is consistent with #2, in that the feature occurs at (approx) the same height on the right-hand unit as on #2 (for the same height unit), and is around the same absolute height on the shorter and the taller unit, i.e. it is not a constant offset from the ridgeline. This suggests to me that is is not a slumpting characteristic as that would distort to the same shape as the ridge section is identical for all three. So I'm thinking: Bill's suggestion of the lead screw: I'm happy to grease it, but how does one clean it? Do I have to dismantle the unit for this? Is the slicing working as expected? Mike Trice has offered to look at the slicing that I'm getting, and I'll take him up on this... Is the transparency of the clear resin causing problems, as a couple of you have suggested? I'll try some more normal resin - and I'll stir it between runs. And, as a further complication, here's another test piece, hot off the printer (and primer). This one is the same sold shape, but stood up on its back end: Sorry about the grit in the primer(!), but it clearly shows some variation in the lower layers, around the area that has been causing concern?? Apologies for the long post - and thanks for all your help! Rob Link to post Share on other sites More sharing options...
MikeTrice Posted March 28, 2021 Author Share Posted March 28, 2021 I cannot see any issues with the sliced .photons file. Link to post Share on other sites More sharing options...
billbedford Posted March 28, 2021 Share Posted March 28, 2021 10 hours ago, tebee said: because it's semi-liquid it's getting squished outward in the build plates downward stroke, you get a little extra resin traped each time which then gets part cured. Eventually this extra resin slumps downward under gravity, forming the too thick layers. Errr no. SLA/DLP printing works by curing a layer of resin trapped between the tank film and the last layers that were printed. The only way to thicker layers is to have a bigger gap between the film and the work. Link to post Share on other sites More sharing options...
paul9415 Posted March 28, 2021 Share Posted March 28, 2021 Firstly I think the suction Mike is talking about is that between between the exposed layer of resin & the FEP .If you have printed a large flat area on the build plate then there is a large area of suction as the build plate lifts away from the FEP which might be causing the distortion.My other thought is if the in the photograph is going against the building , is being weathered & in N scale -how noticeable will it be ? Link to post Share on other sites More sharing options...
simon br blue Posted April 2, 2021 Share Posted April 2, 2021 Recently I was looking at getting another resin printer and after looking at the various options I went for the Mono X. I've printed a couple of parts to see how they came out. I've used Chitubox for the slicing and used the standard settings for grey resin. The first part printed was the test cube, people seem to have varying results with this and my cube came out ok but the text in the middle wasn't perfect. Anycubic test print by simon br blue, on Flickr I did couple of other test bits done to see how fine and smooth some parts were, below is print of a 4mm class 58 fan grill. The grill is 17mm diameter and the mesh is 0.2mm thick. This printed fine but I had to manually adjust the supports to remove them from the grill. 4mm class 58 grill by simon br blue, on Flickr Also printed was a set of 4mm springs for the Heljan class 58, this came out smooth and the damper spring was strong enough to not get damaged during cleaning. 4mm class 58 springs by simon br blue, on Flickr Another grill test was done with open mesh and a bodyside braces behind the grill. I did print this part in 2 orientations and the one pictured came out better when printed vertically. I had tried this previously on my Form 2 but could get it to print reliably with the open mesh. 4mm bodyside grill by simon br blue, on Flickr Overall very impressed with the printer and compared to the Form 2 its much quicker printing. Just one question for the Mono X users on here - has anyone tried tried reducing the UV power setting and cure time as it has been mentioned that the standard setting over cure the standard Anycubic resins. Link to post Share on other sites More sharing options...
MikeTrice Posted April 2, 2021 Author Share Posted April 2, 2021 If you have not already done it fit a screen protector. I am running mine at 80%. I will at some point do an Anti-aliasing test which will involve reducing the power further and increasing the exposure times to greater than 3 secs. 1 Link to post Share on other sites More sharing options...
Quarryscapes Posted April 3, 2021 Share Posted April 3, 2021 What happened here? I suspect I overheated the resin, or overshook it or something along those lines. The weird patch ends at the point I poured more resin into the vat. I'd heated the resin by a heater as the room was cold this morning and this was going to be a long print so I wanted to get started. Most of the supports failed in the odd region, which has gone like chocloate that's melted then solidified in it's wrapper. I let the print finish because I wanted to test the support scheme. I'll reprint tomorrow with redesigned supports and hopefully no temperature issues! Link to post Share on other sites More sharing options...
MikeTrice Posted April 3, 2021 Author Share Posted April 3, 2021 Hard to tell without seeing how you supported it. Beware that an open wagon will by its nature create areas of suction that can rip things off of supports. You might need to add a couple of vent holes. Link to post Share on other sites More sharing options...
Quarryscapes Posted April 3, 2021 Share Posted April 3, 2021 1 minute ago, MikeTrice said: Hard to tell without seeing how you supported it. Beware that an open wagon will by its nature create areas of suction that can rip things off of supports. You might need to add a couple of vent holes. The weird end has nothing to do with supports. The supports not forming was a result of whatever the weirdness was, not the other way round Link to post Share on other sites More sharing options...
paul9415 Posted April 4, 2021 Share Posted April 4, 2021 On 16/06/2019 at 08:35, Skinnylinny said: With the Photon, I have been able to print Stroudley (26 foot) carriage bodies in one piece. I would reckon on doing bogie coaches in at least two parts, and glueing them together. My next projects are some LSWR bogie carriages. I'm still figuring out the best orientation to print parts, to avoid support marks on visible surfaces while minimising warping/risk of parts not adhering to the print bed. I can highly recommend joining the Facebook group "Anycubic Photon Printer Owners" ( https://www.facebook.com/groups/AnycubicPhoton/ )if you're on Facebook - there is a very very active and helpful community there with a huge wealth of knowledge. If you have a question, someone will almost certainly have asked it before and had at least half a dozen replies! Regarding the level of detail that can be produced with the Photon, I have been absolutely delighted - this wagon print is at 4mm scale, and the rivets and other details have come out beautifully, being drawn as 0.2mm diameter and 0.2mm depth. The Stroudley full-brake carriage here has quite chunky (!) handrails (0.5mm) but I have seen these successfully printed (albeit slightly not-straight) at 0.3mm. The slight stepping at the bottom of the carriage side is due to the turnunder and the carriage being printed flat on the bed - had I printed at an angle it would likely not have occurred. I'm especially delighted with the solebar bolt-heads. Lovely work!, amazing what detail You can achieve .My major concern I have is how fragile is the resin re fitting brass bearings & springing the wheelsets in & out ? Link to post Share on other sites More sharing options...
RMweb Gold JCL Posted April 16, 2021 RMweb Gold Share Posted April 16, 2021 (edited) Posted in the wrong thread Edited April 17, 2021 by JCL Link to post Share on other sites More sharing options...
drduncan Posted April 16, 2021 Share Posted April 16, 2021 Dear all, My photon mono (not a X unfortunately) has just arrived as well as a bottle of elgoo water soluble black resin. Can anyone give me the optimal exposure settings for this resin on the mono so I can tune it all in using one of those downloadable exposure test pieces? Thanks Duncan Link to post Share on other sites More sharing options...
RMweb Gold JCL Posted April 17, 2021 RMweb Gold Share Posted April 17, 2021 (edited) Ok, right post, right thread. Mike, you were looking at antialiasing a short time ago. Here’s a couple of posts from a Lychee slicer FB group “Standard is meaningless on the MonoX because you have to slow down printer below 3seconds in order give the printer enough time to read the USB stick 8 times and generate its blur on the fly. I've had great results using "Blur". I may be wrong, but it seems to be *effectively* the same thing, only doing it in advance and making it part of the file instead of asking the printer to do all the heavy lifting. Basically. It takes several seconds for the firmware to read the frame 8 times, apply a gradiated blur and then expose. So you wind up having to go over 3seconds of exposure. Meaning you have to dial down the UV% way low to compensate... like 30-40%. That totally defeats the value of a fast mono screen printer. You don't subvert it. Its a flaw. Done. Deal with it. Instead you just don't use the built-in "standard" a.a. Using blur in Lychee where it *pre*blurs the images instead of relying on the firmware of the printer to do the work is the best work-around I know at this time.” His settings are: radius: 10px grey offset: 50% antialias on supports: off The original post is here: https://www.facebook.com/groups/LycheeSlicer/permalink/793114854944253/?__cft__[0]=AZVlTqVdlYSGLpo9G2S0KEMUcYKPXxHWHhbSDAkeFnz0mvOo2rhYM2ofAzUM0UQD_vozRiQZkHtQKYZpLQWdbEK4zaR1sttobHbBlgc-nf4p1dKF543c1JgxQI-FYUoFERnh95Jx_h8johhbpltyTW1sZdE8q5kAK1onwHUOPO_UR1lT6p0Xyn0H7EdL1szP7SY&__tn__=%2CO%2CP-R Edited April 17, 2021 by JCL 1 1 Link to post Share on other sites More sharing options...
Quarryscapes Posted April 17, 2021 Share Posted April 17, 2021 22 hours ago, drduncan said: Dear all, My photon mono (not a X unfortunately) has just arrived as well as a bottle of elgoo water soluble black resin. Can anyone give me the optimal exposure settings for this resin on the mono so I can tune it all in using one of those downloadable exposure test pieces? Thanks Duncan Here's my spreadsheet with default exposure times by layer height and a calculator as well as optimal angle by layer height. 3D PRint ANgle finder.xls Link to post Share on other sites More sharing options...
Quarryscapes Posted April 17, 2021 Share Posted April 17, 2021 Happy days here! Updated firmware on the Mono so now I have 1) Anti Aliasing and 2) Chitubox sliced files now actually work instead of just printing strands of spaghetti on my build plate. I also printed a thing: It was a close run thing though, It did actually run out of resin at the very end of the print. No harm done though. Drip Angle Holder.stl Link to post Share on other sites More sharing options...
beingamonkey Posted April 17, 2021 Share Posted April 17, 2021 Hi, new to this thread, it's been really helpful and convinced me to take the plunge and buy a photon. I ordered a Photon Mono a few days ago with a Wash & Cure Machine 2.0 & 1kg of resin, but so far only the Photon Mono and 1kg of resin has arrived (by separate carriers), is this normal for these to all be sent separately? I've sent a message to AnyCubic, hopefully my Wash & Cure Machine 2.0 is still on its way. Just wondering if anyone had any similar experiences. Nic Link to post Share on other sites More sharing options...
Quarryscapes Posted April 17, 2021 Share Posted April 17, 2021 4 minutes ago, beingamonkey said: Hi, new to this thread, it's been really helpful and convinced me to take the plunge and buy a photon. I ordered a Photon Mono a few days ago with a Wash & Cure Machine 2.0 & 1kg of resin, but so far only the Photon Mono and 1kg of resin has arrived (by separate carriers), is this normal for these to all be sent separately? I've sent a message to AnyCubic, hopefully my Wash & Cure Machine 2.0 is still on its way. Just wondering if anyone had any similar experiences. Nic Yes, totally normal, but also incredibly annoying. Link to post Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now