3d printing process

[Egilman]

21 hours ago, thibaultron said:

Check that Chitubox supports your brand and model of printer.

It does, for over a year now...

[Egilman]

15 hours ago, Dr PR said:

I have been using the free Chitubox and I am satisfied within how it works. Their tech support is pretty amazing, often responding within a few minutes to my email questions!

 

1. You can create custom settings for different resins and save them for future reference.

 

2. You can add settings for any printer - if you know them. For my Anycubic Mono I just started their Photon Workshop slicer program (not nearly as good as Chitubox) and copied the settings from it.

 

3. Chitubox sometimes doesn't add enough default supports and the print fails, leaving the part stuck to the FEP film. I have been manually placing supports with mostly good results. Most of the failures I am seeing are always due to not enough supports near edges and corners. If it isn't supported a surface will flex during printing and come out warped. Another related problem is supports that are too narrow at the contact point with the print part - the support doesn't connect to the printed part and is worthless.

 

4. Chitubox offers many options for designing individual supports, including the base shape and size, support shape and width, support end diameter, shape and depth of penetration into the surface. The only thing that doesn't seem to work correctly is cross links between supports. For me these are a nuisance, but turning them off in the settings doesn't prevent the program from adding them anyway. These can make it very difficult to remove supports from fine details.

 

****

 

On another topic, I have using denatured alcohol (95% ethanol and 5% methanol). This was recommended by Anycubic for cleaning their Basic Grey resin. It is sold in gallon cans for about $18 the last time I looked - look for it in the paint stripper and wood finish products. It has always been cheaper that 95% isopropanol (isopropyl alcohol), primarily because it is available in gallon quantities.

 

****

 

And now a question: I read in someone's post that they used hot water or a heat gun to soften warped pieces and then bend them back into shape. Has anyone tried this? Do you heat the part before curing or after?

 

The single greatest frustration I have found with 3D printing is that thin details like hand rails are often distorted by the forces of separating the print from the FEP and then pressures from resin flow as the part returns to print the next layer. These parts are always bent between the supports, and often come out "fat" in between supports. So far this problem has made 3D printing useless for many of the things I have tried to make. If I can reshape the warped railings and pipes after printing there are a lot more things I could use 3D printing for.

Gonna give CBox a try, it looks like it isn't much different then Lychee in what it offers in the free versions.... Both of them do not create enough supports in their auto routines and I've kinda figured out that most print failures/problems are lack of sufficient supports or insufficient exposure.... It's part of the process I guess just have to get used to it like everything else, experience is the best teacher...

 

I've heard about Denatured Alcohol and Home depot sells it relatively cheap as well... might give it a spin when I need to refresh the alcohol again... Right now I'm still learning about that as well. coming out of the wash n cure, the parts are clean, but my build plate and sieves for screening resin are beginning to pick up a sticky residue that doesn't come off in the wash... I'm sure it's partially cured resin, but how does one get it off? Alcohol isn't cutting it... (even after soaking in alcohol for several days)

 

I'm beginning to come to the conclusion that there is a level of detail that 3D printing cannot replicate... Very very thin parts/surfaces are one of them, surface detail as long as it is securely attached to something seems to work fine but anything else is a lost cause, but then I haven't the experience to tell one way or the other...

 

Thanks for the responses Phil, I've never had to adjust a resin casting or print in hot water yet, plastic yes I've done that and it works... I assume from the many stories of it on the net that it works as well for resin as well...

 

Still learning the process here... will report on any unusual experiences...

[Egilman]

12 hours ago, Kevin-the-lubber said:

Egilman, what’s the cream-coloured resin in #259? The result looks better than the grey resin? I use way more supports than you, I’ve just gravitated towards more over less over time, as I was getting frustrated by the fails. To get over my recent hump of fails I had to increase the exposure times quite a lot, the point being that I’m having to use different settings for the same object, printer, resin etc from those which were successful last year. I guess (printing seems to always involve a lot of guesswork!) this is down to temperature, humidity etc.

 

Kevin those cream colored parts are the kit's engine, styrene plastic... I've learned about the support issue, (more is better) and exposure is more dependent on the resin and environment than the machine is apparently... I've pretty much decided to do a RERF print on each resin I use at the time I'm using it as a calibration test for that session... I've got mine inside my hobby room so that is a kind of environmentally controlled situation... shouldn't have too many issues that way but I will still make sure beforehand...

 

There's a lot more to this than just printing...

[Kevin-the-lubber]

That's pretty good moulding if that's the kit part! If these ship kits were that decent I probably wouldn't have even got into printing 🤔. I see the difference now, comparing the solidworks snip to the kit part - you're including far more detail. I find that anything extremely small, 1/100 bolt heads for instance, can end up looking like these are 'zits' rather than intentional unless there's a strong pattern, but it's still surprising what you can get away with. I printed the most delicate filigree pieces for the Victory that are only about 0.2mm wide and thick, an absolute nightmare to get off the supports, but I was still impressed that the machine could do this. I guess though that we will always want one more level of detail, it's the nature of the game.

 

 

[mtaylor]

Egilman, I think you have the right idea about test prints.   I make test cuts on a laser cutter before feeding it the drawing just make sure nothing changed.  Many moons ago I worked in a place that ran large Cincinnati Milling Machines.... and if the machine was shut down overnight or for maintenance, they ran test run on it .

[Egilman]

5 hours ago, Kevin-the-lubber said:

That's pretty good moulding if that's the kit part! If these ship kits were that decent I probably wouldn't have even got into printing 🤔. I see the difference now, comparing the solidworks snip to the kit part - you're including far more detail. I find that anything extremely small, 1/100 bolt heads for instance, can end up looking like these are 'zits' rather than intentional unless there's a strong pattern, but it's still surprising what you can get away with. I printed the most delicate filigree pieces for the Victory that are only about 0.2mm wide and thick, an absolute nightmare to get off the supports, but I was still impressed that the machine could do this. I guess though that we will always want one more level of detail, it's the nature of the game.

 

 

Thanks Kevin,

 

Oh the Kit is beautifully molded, my issue with the engine that prompted this printing excursion is it isn't an accurate representation of a J-47 at all, it merely represents the engine.... putting the two side by side tells that tale all to vividly... At 1/32nd scale I can get 9/16ths bolt heads quite well, 7/16ths don't come out that bad either, (the kit molding didn't even attempt bolt heads) but flat panels, (like the air islands here) need to be at 1/4th inch to show up on a flat surface.... That's .008" thickness to show the definition... That's the scale factor for you the smaller you go in scale the less you can represent... It can do very delicate relief work or raised details but even such there are limitations... That's half the battle to getting good results, learning the limitations of the medium...

 

On this engine I've a lot of tubes and wires that need to be printed as well, too small at 1/32nd scale to print by themselves, I'm going to have to figure out a representation that makes them look accurate but prints along with each section... 

 

Still some challenges to figure out... 

 

But yeah the abilities of the machine are impressive to say the least... this is way beyond what I was hoping for...

[Egilman]

4 hours ago, mtaylor said:

Egilman, I think you have the right idea about test prints.   I make test cuts on a laser cutter before feeding it the drawing just make sure nothing changed.  Many moons ago I worked in a place that ran large Cincinnati Milling Machines.... and if the machine was shut down overnight or for maintenance, they ran test run on it .

Thanks Mark...

 

My first job out of Machine school was running an old Cincinnatti 2MH mill in a tool room set up for punched tape CNC... And yeah we had to calibrate it every run...

 

Several sources off the net especially that one Ron posted above led me to the conclusion that each and every Resin is different and requires the printer to be calibrated to print it, (even between new batches of the same stuff) when I finally got into setting up Lychee and discovered that they have it set up as well to save resin settings in a clickable database for repetition, that pretty much confirmed that bit of knowledge... They wouldn't do that if it wasn't a real issue...

 

Test your resin on your printer before you print with it, then set your printer up accordingly, a little bit of resin thrown away but a lot less headaches with failed prints...

Edited May 30, 2022 by Egilman

[thibaultron]

Something "interesting" I found out about Sketchup today, at least mt 2017 version. Well really two but one lead to another. I'm designing an interior for a brass HO passenger car I have. So I designed it to a scale 10 7/8" length on my regular CAD program, and transfered it to SketchUp using an old Pro version I have, just for such activities. I had earlier discovered that when I do this, I use inches in my regular CAD, but when I import the drawing (DWG) into my older version converts it from inches (say 100") to feet (100')! So for this interior, I went ahead and shrank it back to the 10+ inches.

 

Then I started to work with it, SketchUp does not like to use fractions of an inch smaller than 1/16th or 1/32!! This makes generating small parts difficult, you start to run into gainyish issues.! I can manipulate the original I imported, but sometimes trying to generate new "things" causes it ti cought. So from now On I design my stuff Full scale, then shrink it down!

[thibaultron]

Does anyone know if we can post an Excel file on the forum? I have developed one to calculate the best angle to print your model at to give the upper surface the smoothest finish, based on a couple of YouTube videos. I would hate to try to explain how to create it for yourself, as it gets into some deep "things" to insert the formulas, into the spreadsheet.

[Kevin-the-lubber]

I think you can attach any kind of file you want.

 

After months of failing to achieve dead straight edges on, for instance, large box-like shapes, I think I’ve finally worked out the (obvious) solution. I tilt the object on two axes, Z And X or Y. This means there is never a straight edge parallel to the build plane. It means more waste as the supports are longer, but it works.

[Dr PR]

Just drag the excel file or use the "choose file" option (seems to work best for some folks) to open a file window and select the file. It will be interesting to see how well it works.

[thibaultron]

After watching the video about how to calculate the best angle for a print to be placed at, to get a smooth surface, I created a spreadsheet to do the calculations. This means I don’t have to rewatch the video every time I want to find the angle! The formula involves finding the angle of the Arctangent of the layer height/pixel height. Don’t run away yet, I know trigonometry hurts, but it will be worth it!

 

The video is at:

 https://www.youtube.com/watch?v=Qs2Rb0ExnIM

 

Here is a diagram of the calculations

 

The video explains it more but the diagram sums it up. I developed a spreadsheet to do the calculations.

 

This is a screen shot of the spreadsheet.

 

As you can see I pasted a copy of the diagram into the spreadsheet to remind me of what I’m looking for.

 

The first section takes the Layer Height and Pixel Size values and uses them to calculate the (90 degrees - ArcTan) value that is what you need to rotate your model to, in your Slicing Software.

 

 

In the spreadsheet I’ve entered the pixel size for my Anycubic Mono 4k printer, the Sonic 4K uses the same pixel size. I found the value by looking at the specifications on the Manufacturer’s site. The Layer Heights I entered are a range of the standard ones for most newer printers. You can replace these values with those of your printer, just be sure not to mix up the pixel and layer values. The last line in this section (with the Red text), is for use if you have some special layer height you need to use.

 

Sometimes you need to place your model at a certain angle to make it fit in the total print volume. For instance, I am designing a model of a specific Santa Fe business car, and a side will just fit diagonally inside the print volume. Therefore I can only print it at a fixed orientation. The second section calculates the Layer Height I need to print this at to get the best surface.

 

 

You enter the angle in the Red text area, and the spreadsheet calculates the correct layer height to use. In the example I used the angle shown in the diagram.

 

Naturally, by picking one surface to be the best, the others will print with more artifact lines, but at least you can determine which surface is the most important. For example, in either the above video or another the YouTuber used a tank body as an example. He wanted the top to be the smoothest surface, as this is the most visible one. He accepted that the back and front might have a slightly rougher finish.

 

I hope this spreadsheet helps you!

General Angle Values For Printing Aflat Surface on a Resin Printer_002.xlsx

[Thistle17]

Ron et al I am not at all critical of your works as a matter of fact I marvel at your bringing the "sciences" into the realm of model building. What have we wrought in just the last few years and maybe more importantly where is it all going?

 

And the other sense I gather is that 3D printing may be more complicated than say CNC or laser machining. Your discussions sugest that in these cases the material brought to the machine is lessof an issue in some respects. But in 3D printing the material is somewhat "one with the machine" if you get my drift. Am I wrong?

Joe

[Nirvana]

18 minutes ago, Thistle17 said:

But in 3D printing the material is somewhat "one with the machine" if you get my drift. Am I wrong?

Joe

Joe, yes you are right. The filament can be made of various material, PLA currently most common for hobby purpose. All the filament will be extruded and heated before being "plated".

[thibaultron]

Joe, you are not wrong, but like any material you use in a hobby, learning the materials is part of the process, be it wood plastic, resin, etc.

[Egilman]

3 hours ago, Thistle17 said:

Ron et al I am not at all critical of your works as a matter of fact I marvel at your bringing the "sciences" into the realm of model building. What have we wrought in just the last few years and maybe more importantly where is it all going?

 

And the other sense I gather is that 3D printing may be more complicated than say CNC or laser machining. Your discussions sugest that in these cases the material brought to the machine is lessof an issue in some respects. But in 3D printing the material is somewhat "one with the machine" if you get my drift. Am I wrong?

Joe

 

36 minutes ago, thibaultron said:

Joe, you are not wrong, but like any material you use in a hobby, learning the materials is part of the process, be it wood plastic, resin, etc.

Absolutely! materials and techniques are the backbone of this hobby, without understanding them and how to work them, there wouldn't be a hobby.... Look at the different materials used in painting artwork and the different techniques to apply it... The same goes for model building, master the materials and the tools to work it, master the craft...

[thibaultron]

Well, tried my first "real" print today. Fail! I think there were a couple problems.

 

1. This is the first file I sliced a month or so ago, and I'm not sure I even got the supports close, I think I modified them to reduce the diameter of the supports where they intersect the print, and they were too weak.

2. I forgot I had reduced the light output from the factory 100% to 80%, and I ran my R_E_R_F print at 100%, so my exposure setting was too low.

 

I re-supported the file using both the default medium, and heavy supports at the first exposure (2.3 seconds), and another file at 2.75 seconds exposure. I'll try the 2.75 first tomorrow, If that is successful I'll retry it at 2.3, just as an interesting test.

 

This is what the print should look like after the supports are removed.

 

This is what printed. Sorry about the blurry picture, I can't find my camera, and my Kindle is really pour at close up photography. The finished print should be about 2+ inches long.

 

This is a screen shot of the Lychee file for the above locomotive skirts with both the medium and heavy supports. I'm going to print both at the same time.

 

 

Once I get a good print, the next one is a short section of the side of the HO passenger car I'm designing. I just want to see if the rivets, and the various layers of steel on the side come out alright, as well as determining if I have to adjust for the resin changing size as it cures. I'd hate to lay out a few hundred rivets, only to find out I need to make them slightly larger to print well!

 

Here is a picture of the section of car side. The rivets are a scale HO 1" in diameter. The various layers are a scale 1/4 inch thick, and one window (left one) has the half round sill. The whole side is a scale 5 inches thick., and the section is 30 scale feet long.

 

Here is the Lychee file for it. This will also test how smooth the surface of the side is, as I used the ArcTan spreadsheet program to calculate the angle (49.4 deg) for a 35um layer height. I'm also running into a problem with this file in Lychee. I import the STL for the section, it says there are no errors. I add the supports, and it is happy. I save the sliced print file, and it is happy. I save the STL of the supported part, and it is happy. Then when I import the supported STL, it says there are errors! If I tell it to fix the errors, it crashes! Then it keeps restarting Lychee, and crashing in cycles. I have to restart the computer to get it to stop! The print is in red, because I imported it for this screen shot.

 

[Dr PR]

I use Microsoft's "3D Builder" program (free download) to repair faulty files. It works very well. I also use Chitubox (also free) for the slicer.

[henrythestaffy]

Ron,

        When I use white resin the printer is set to 60 seconds for the first five layers and then 6 seconds for the rest. How did you arrive at 2.3 seconds for your print? Do you use the slider in the slicing software to simulate the print? It is a great tool for identifying "islands" which are the bane of all resin print jobs. Using default support positions will only go part of the way to a success print. I would also look at angling the parts so that the angled edge is printed first and gains a nice connection to the supports before the strain of a full edge is printed. 

 

Paul

[thibaultron]

The car section I am having problems with, has been checked with Netfab, and passed, and Lychee said it had no errors when I imported it. It is the supported file that Lychee saved as a STL that Lychee is having problems with.

 

I used the Anycubic R_E_R_F file results to get the 2.3 second value, but at 100% light level, I forgot that I had reduced it to 80% to save on wear of the LEDs and LCD screen.

 

These are small parts (2" long by .05" thick each), so I didn't angle them, if the next prints fail, I'll try that.

[thibaultron]

Well the second print of the skirts came out much better! These were done at a 2.75 second exposure, 50um layer height, and 1 minute cure time.  Again the pictures are blurry, due to the limitations of my Kindle camera. My phone camera does much better, but a couple of months ago my computer stopped recognizing it, I suspect after one of the MS updates..

 

Again here is the sliced file

 

Here is the print of both the medium (left) and Heavy (right) support versions. If you look at the tips at the far right, you will notice that bottom of the tip is curved up. I forgot to add supports for the tips at that end.

Here is the best I was able to do for a close up of one of the skirts. Trying to hold the part behind my magnifying light and balance a Kindle in front was quite difficult.

 

And finally here is three of the skirts. The other 5 turned out to be in shadow when i looked at the picture on the computer.

 

I will have to slightly modify the final print, as the bar across the two sections broke when I removed the prints from the supports, and I will add the extra supports and tilt the print, to perhaps help with the tip problem. The fact that I forgot to remove the supports before I cured the prints may have added to the bar breaking.

 

All together though I'm pleased with these, they were just test prints. When I go to print the final ones, I will have to use a better resin, this one is to brittle. Probably I'll use Siraya Tech Build, which is a bit more durable.

 

I would like to thank my cat for helping me write this, the blocking of the monitor, and keyboard, as well as the random key hits was enjoyable, Not!

 

[thibaultron]

Figured out Lychee's problem with the car side. I imported it into Netfab, and the problem was in the supports Lychee added!. Netfab fix, whatever it was, and now Lychee's happy.

[thibaultron]

As promised, here is a more detailed write up on my passenger car test print.

 

Santa Fe Superintendent’s Car In Ho Scale

 

 

Finally got a test print of the rear of the car printed! I wanted to make sure the 1” scale rivets would print out on my Anycubic Mono 4K printer, as well as seeing how some of the other features appear.

 

The short answer is, fantastic! Maybe too well in fact.

 

Anyway, let’s start at the beginning. The railroads used Business Cars for the travel of the upper management during railroad related activities, and the occasional personal ones also (the perks of position). These resembled regular passenger cars, but were better outfitted. The Santa Fe in addition had smaller slightly less fancy cars for their division supervisors, that were used as they traveled back and forth across the tracks they were responsible for. There are only a few HO Scale models of these cars, two offerings from brass importers, and an old somewhat crude (by today’s standards) 1960s vintage stamped metal sided kit, all out of production. The brass models, when you can find them are expensive, and one model from Hallmark, only represents one of the 20 or 30 cars in the class. During their lifetimes (1920s through early 70s), they were modified, many extensively when air conditioning was added, and some changes were made when different groups of cars were delivered in the 1920s. These cars were also shorter than the regular 80 foot long business cars, at about 60 feet long.

 

Anyway, after many months of drawing and correcting as I found new information, I’ve final reached the point being able actually 3D print something! In this case just a test print of about half of one side. I wanted to test both the printer’s ability to print details such as HO scale 1” rivet heads, and the height difference between layers of steel sheets, and the visibility of those features.  I didn’t want to lay down several hundred rivets on top of two differ height layers, only to find that they didn’t print at that size!

 

The 3d file for this test is shown here in a screen shot from the Lychee slicer I used to create the print files. This has one row of vertical rivets along the left side of the leftmost window, as well as the various levels of steel sheets and trim. That window also has the window frame recessed and the half round outside window sill. The section of the car side is 30 feet long. The print took about 16 hours to print, at a 30um layer height. The 30um height was chosen as one full length side fits inside the printer’s print volume at about 50 degrees of tilt, and with this printer placing the print at 49.4 degrees with that layer height gives the smoothest surface finish to all those large flat areas. Just take my word for it. I developed a nice spread sheet based on some Web write-ups and videos, to calculate those settings. The print was done at an exposure of 2.2 seconds per layer using Elegoo Standard Rapid Gray resin. When you go to thinner layers, you need to reduce the exposure time by ½ of the percent difference in the layer height. So from my standard exposure of 2.75 seconds for the standard 50um layer height (30 being 40% less than 50), I reduced the time to 2.2 seconds or 20% less (technical jargon portion finished).

 

After about 16 hours of printing I had this finished print (Yea! No failures) hanging from the build plate.

Settings

 

And the important end of the printed side. I have, unfortunately misplaced my camera (messy shop) and this is the best shot I could get using a magnifying lamp and my cell phone camera.

 

 

The rivets and layers printed out perfectly! Unfortunately, they may be too fine to actually be seen, once a car is painted! So I’ll have to paint this and see what it looks like.

 

Here are some photos of an actual passenger car, I took at my local museum, and the rivets stand out much more in person, even though the printed rivets are completely scale and the same size as the ones on this car.

 

There is a problem with the print itself. If you look closely at the photo you can see that the left side of the window ID bowed out a little towards the inside. I’ll have to add some additional supports to these surfaces.  The part came out to within about a scale ¼ inch over the 30 feet, so I’m satisfied. The print is also flat, and over the last few hours has remained so (sometimes a problem with resin parts).

 

 

And a shot of the car behind this on to show a view from a slight distance

 

 

These pictures were taken with the sun behind me, so that could be adding to the contrast.

[thibaultron]

Here are some pictures of the locomotive skirts I printed out a few days ago, as applied temporally to the model.

 

First the model without the skirts

 

 

Now with the skirt parts just set in place. The chunk missing from the bottom left of the right skirt, happened when I was removing a reinforcing band used during printing. Shows why I will have to use a les brittle resin on the final parts.

 

The skirt parts are just set in place. The square tab at the top would be trimmed when finally installed. I have to thin the skirts a little, they stick past the inside of the shell and would prevent removing the shell from the frame, for servicing. I also have to remove some of the detail from behind that area, as the details stick out a little past the shell. I may also add tabs behind the skirts, and mount them to the frame rather than the shell.

[thibaultron]

Santa Fe Superintendent’s Car In Ho Scale

 

Part 002

Painted the car side and a print of the oil bunker today. The paint I used is a bit darker than what the final model will be, but it does what I wanted, make the details Pop!

 

Here is the picture of the test piece now

 

 

All that scale detail does show. It is even visible at normal viewing distances. What a relief! You can even see the beveling of half round window sill ends.

 

One bad thing is how visible the layer lines are, even at the ideal angle, once painted. I’ll have to think on this as there will be lots more rivets, which will make sanding these difficult, and a filler type primer may make the details disappear, and still require sanding. I may try printing this vertically, and see how that works. To do this I’ll have to print a side as two pieces, but that can work.

 

Here is a picture of the rivet detail on the bunker. The overall print failed, but I’ll talk about that later. It does show that the rivets print crisply. The rivets are a scale 1 1/2 inches in diameter, spaced 1 5/8 inches on center. So detail wise the printer is doing great. The layer lines are also present on this , but they were also present on the ShapeWays print I had done quite a while back. The ShapeWays rivets could be seen, but they were connected by shallow valleys.

 

 

[Patrick Matthews]

And sometimes we print parts for things that float!

 

 

Railings- sometimes there's more resin in supports than the parts:

 

Many of the parts needed for this inland rivers towboat:

[Patrick Matthews]

And it doesn't all have to be printed. The house above is wood and styrene, with printed details. 
My 1:8 R/C DUKW axles work better with some brass parts:

 

Printed wheels, rubber tires from a printed mold:

 

 

Brass tubes because the printed ones I made before actually sagged ("crept") under load:

[Patrick Matthews]

Got something long that won't fit in your printer? You may be able to break it into segments, with strategic glue joints. I made a 20 inch long railing section this way, with half-lap joints in the rails.

Joints were made with CA, but I still had some tiny gaps. These were filled with printer resin and zapped with a UV flashlight. Filed smooth, the joints are invisible.

 

 

Long continuous railing:

 

 

Lining up the segments:

 

Half laps:

 

 

You can use resin to fill gaps. Here I'm filling seams in styrene overlays. Use a UV flashlight and UV safety glasses:

[thibaultron]

The other day I printed out the case of a resin printer heater designed to fit inside the printing area of the printer. I wanted to insure that it would fit, before buying the two most expensive parts (the heater/fan, and the power supply. It does indeed fit inside my Anycubic Mono 4K, so I'll order the rest of the parts. Once it is built I can Use some of the resins that require 25C/77F, or more, for best results. In the winter I can't get the shop that warm with my space heater, and in the summer the temp will drop at night, and 77F is a little warm for doing any type of physically active work.

 

Here is the video I found on the heater, files are listed in the description block:

 

 

[thibaultron]

I updated/expanded my spreadsheet on calculating the best angle to place your print at for the smoothest surface finish. The new spreadsheet now includes a calculation for what exposure time to use when printing thinner layers. As you decrease layer height, less exposure time is needed to cure the thinner “strip” of resin, as the light has less material to shine though. I’ve also added a new calculation to show the correct angle to place the print on, should you desire a specific layer height, rather than the other one that showed the correct layer height for a specific angle (still included on the sheet). I’m not sure how useful the new calculation will be, but I figured it was good to include it.

 

 

General Angle Values For Printing Aflat Surface on a Resin Printer_017.xlsx