Finally switched to DLP.

[peteski]

I take it the board gaps are acceptable?

[Lemosteam]

Chris, the roof has a slight angle, not curved, but up close the roof is perfectly smooth. I am blown away. I printed with 3 second exposure and 0.03 layers. The roof is tilted at 43 degrees from horizontal.

I will try to print something with a curved surface tomorrow to share. I mean Bryan’s original post of his greyhound bus sold it for me long ago, actually. I just was sick of dealing with the LCD screen print failures forcing me to peel thick misprints off the FEP, and replacing feps. I went through three feps in one week, printing that dang caboose shell.

The first thing I noticed was the super crisp edges.

Funny story, my first attempted print was a failure, but not because it didn’t print right, the version of Chitubox I was using essentially slowed the printer to an almost imperceptible crawl. The computer screen showed a couple hours+ and the printer screen showed almost 28 hours! I mean I could barely tell if the screw was rotating. So I stopped the print and only the first layer had printed after 15 minutes.

What blew me away though was the perfect layer edges, and I mean perfect circles for the magnet holes, perfectly straight sides, no ballooning etc. 

Once I got the software fixed, I was printing away. I had not had this many successful prints in a row-ever.

To me the biggest advantage is the lack of an LCD at all. Just reflected light coming straight up through clear glass. I had already replaced my screen once on the mono costing me nearly half what I paid. Another advantage is the layers seem mor hardened by the direct light. I recall in the beginning how you would modify the slice images to reduce gray pixels!

The disadvantage is the print volume that I was used to is just gone. I REALLY hope they come out with a larger DLP printer. I’ll be first in line.

[Lemosteam]

OK how did you do the wood grain?

I actually printed 12” plank board gaps in the design. The happy accident was as I was cleaning the mod3l I used a toothbrush in the alcohol bath and it left some scratches. After curing, I dragged some intentional grooves into the model using a knife tip, along with some dents on the top rail.

[rodsup9000]

The disadvantage is the print volume that I was used to is just gone. I REALLY hope they come out with a larger DLP printer. I’ll be first in line.

John
 I have 2 AC D2's now I bought my first one right after Bryan showed the bus he printed. Then I bought the 2nd around last thanksgiving.  I use AC DLP Craftsman resin mixed with a little AC tough resin, so the prints are not so brittle.

[Lemosteam]

I'm interested in the underframe kit for the IMRC SD40-2 too....

James many parts will be a slow go as I have to redesign the kits for resin printing, I.e. supports and such.

I will start a thread in Product Discussion soon with initial offerings, and go from there. If there is a design from before and there aren’t many requests for it, I will consider charging design time for that, which would be added to the price of the sale. Future sales of that item would then be reduced.

It will take quite a while to redesign everything, for a typically small return of investment, but we’ll see.

[Lemosteam]

John
 I have 2 AC D2's now I bought my first one right after Bryan showed the bus he printed. Then I bought the 2nd around last thanksgiving.  I use AC DLP Craftsman resin mixed with a little AC tough resin, so the prints are not so brittle.

Aye, I work a little different, you might try it. I like to triple bath the parts, the last being a cold wash in acetone. The swishing actually cools the material, and somewhat hardens it, then I clean off the supports and let it sit for a couple days. It seems to allow the parts the breathe a little before I actually cure them. I have even built kits before cure and cured them after without issue. I like the way the supports I use and the parts are still somewhat flexible during assembly.

Mixing resins freaks me out due to the expiration dates and I am not very compatible with liquids, seriously.

[bbussey]

… It sounds like the only downside of DLP is that stepping shows up more pronounced. Did you have any problems with that? Does that curved roof have layer lines? Just wondering. I was ready to buy a DLP so many times, but never saw a direct comparison with a model railroad item. I mean I can't tell one dragons scaly skin from another.

Not for me. Stepping is much less on the D2, especially with anti-aliasing employed in the slice file. With curved surfaces, I double-angle on the XY planes at the proper arc-tangent which further reduces visible stepping.

[Chris333]

I do use the DLP resin with the ceramic in it. The first time I used it I noticed the parts were still warm when I picked them up to clean.

Honestly have no idea what brittle prints are.

Sometimes I mix in a little acetone with the denatured alcohol in the final wash. Don't let parts sit in there too long. And I hit everything with an air gun before curing.

[rodsup9000]

I do use the DLP resin with the ceramic in it. The first time I used it I noticed the parts were still warm when I picked them up to clean.

Honestly have no idea what brittle prints are.

Sometimes I mix in a little acetone with the denatured alcohol in the final wash. Don't let parts sit in there too long. And I hit everything with an air gun before curing.

The one on the left was the one of the first quick (just added some supports) prints I did on the D2.  Small parts like the muffler that broke off was brittle. By adding a little "AC tough resin",to the DLP craftsman resin helps a lot so that these small pieces don't break

 The one on the right was printed on 8K printer with ABS like resin.

[basementcalling]

OK how did you do the wood grain?

Isn't that just the usual striation lines in a 3d print? Just in this case parallel to the direction wood grain would run? That was my thought.

[Chris333]

I recently printed about 30 prints of a model with two .023"x.023" stanchions protruding straight up about 3/8" and never broke a single one. Even with crazy force with the brush while cleaning.

[Lemosteam]

Nope its a vertical plane, so no striations and I actually modeled the planks, and scraped them after.  The larger barge is a resin casting.

[Iain]

I take it the board gaps are acceptable?

how wide are your board gaps?

[Lemosteam]

They are v shaped grooves with a flat at the bottom.  I cannot recall the dimensions offhand.  I think the width is 0.3mm angled back with a 0.1mm chamfer.  I think the depth is 0.3mm, but I am not sure.  I will have to measure.

I do have a concern about paint filling them though, but the customer has not tried to paint this model as yet.  If I end up having to widen them it will be done using the angle, likely.

[Lemosteam]

Test fit of the D2 prints of the customer’s design. I’m gonna love this machine.



Roof on shell:


Cupola into roof:


Cupola roof:


Final asy sans underbody. Fitment is near perfect.