1:800 Scale Resin Printed USCSS Nostromo (WIP)

[skahtul]

This is my first large scale project with my new Mars resin printer. The prints are amazing and the apparent lack of layer lines is pretty awesome. So far, in my experience, the work is not really more or less than my PLA projects, and there is a lot I don't really like about the resin, even for a medium-sized project such as this. That may change with time but for now, I really like the structural integrity and ease of assembly of my PLA prints.

Anyway, here is my first attempt at a medium scale print/project. And my hat off to the author of the files, as you will see there is a ton of thought that has gone into the assembly and lighting options and the overall construction of the kit.

But, the amount of detail is undeniable, this little printer can print small and complex models without breaking a sweat and it really is amazing. It's also so fast, the print below would have taken days instead of hours.

 

[skahtul]

You can see here that some real thought has gone into the layout of the LED wiring tunnels. This is going to be a very quick build and I don't plan to put in the lighting. This is really just intended to get my feet wet with resin projects. I may print the larger 1:400 scale PLA version, but we shall see how this one turns out.

 

[skahtul]

Most of the major parts are printed, except the engine and 'wing' assemblies.

 

[skahtul]

Glue and putty time. The keyholes for the parts are not lining up 100% in all instances, but I suspect this is more due to warping and distortion of the print and not the files themselves.

 

[skahtul]

Most of the major parts are glues and assembled:

 

[skahtul]

This is my first real issue with the resin printer. I have tried some of these parts in many, many different orientations and they always come out distorted along one edge.

It's a bit frustrating because all other facets and edges are amazing, so sharp they can almost cut you, they look incredable. However, it seems almost no matter how I position the part, the part facing the 'bed' of the printer which of course also has the supports never has a clean edge.

All the distorted seams you see below are positioned at 45 degrees so the edge is facing the printing platform. I may try printing a few parts right on the bed, but my issue here is the suction on the FEP film and the difficulty in getting the prints off the bed.

I am not too worried and I believe I can get it 85% there with my putty skills, which are just mediocre. I am 100% sure there is some way to fix this, it will just require more practice and expereince.

 

[Bauble]

This looks really good. I cant see print lines - amazing. About the problem you have, can you extend the model to carry a sacrificial layer on the problem side and sand that off after the print?

 

[joberg]

Very good all in all...yeah, sure; a few little gremlins here and there but nothing resembling an industrial accident

 

[Analyzer]

Very cool

I had similar issues with the edges facing the plate when printing my Razor Crest. Adding more supports can help, even if they are the small ones especially on those rounded corner areas

Where did you get the files?

 

[skahtul]

Very cool

I had similar issues with the edges facing the plate when printing my Razor Crest. Adding more supports can help, even if they are the small ones especially on those rounded corner areas

Where did you get the files?

Search for "Alien" or the names of the ships on the Gambody site. Someone recently released this kit and an amazing Narcissus that includes a full interior. That one is next up on my list as I have been looking for a Narcissus for years. I have looked at so many resin kits but either they were too small or I was not willing to pay what they were asking for a resin cast.

 

[skahtul]

This looks really good. I cant see print lines - amazing. About the problem you have, can you extend the model to carry a sacrificial layer on the problem side and sand that off after the print?

Very true, it will just be more putty practice than normal

This looks really good. I cant see print lines - amazing. About the problem you have, can you extend the model to carry a sacrificial layer on the problem side and sand that off after the print?

That is not a bad idea, I may give that a try.

 

[Firefox3D]

It's almost impossible to stop a small amount of distortion as the resin shrinks as it cures. The distortion as you have found happens nearest the bed as the model pulls on the supports.

Resin manufacturers rarely say what the shrinkage factor is, but "hard" resins shrink more as a rule, the more flexible resins generally do better for bigger pieces.

If you can orient the model so the sharp corners are pointing straight down with a support direct on the corner do that, but this is not always feasible.

I have found if you have a detailed piece like you are printing, making the supports longer so the print starts say 15-20mm from the bed can help. For large solid things a total overkill of thick supports close to the bed.
Also curing the parts before removing them from the bed can help with the amount of distortion.

Also as commented a sacrificial piece, but that's essentially what the long supports do.

I have been printing large parts to assemble and I add 1mm of overlap to each piece them sand off the extra to get a near perfect fit. These are my own models so easy to do.


Jon

 

[skahtul]

It's almost impossible to stop a small amount of distortion as the resin shrinks as it cures. The distortion as you have found happens nearest the bed as the model pulls on the supports.

Resin manufacturers rarely say what the shrinkage factor is, but "hard" resins shrink more as a rule, the more flexible resins generally do better for bigger pieces.

If you can orient the model so the sharp corners are pointing straight down with a support direct on the corner do that, but this is not always feasible.

I have found if you have a detailed piece like you are printing, making the supports longer so the print starts say 15-20mm from the bed can help. For large solid things a total overkill of thick supports close to the bed.
Also curing the parts before removing them from the bed can help with the amount of distortion.

Also as commented a sacrificial piece, but that's essentially what the long supports do.

I have been printing large parts to assemble and I add 1mm of overlap to each piece them sand off the extra to get a near perfect fit. These are my own models so easy to do.


Jon

Awesome, thanks for the advice. I am printing a part right now and I have the edge pointed at exactly 45 degrees directly at the bed to give it a test.

Thanks again!

 

[Firefox3D]

Another thing you can do is download and install a copy of the PreForm software as the auto orientaion in that can be quite a good guide, it does do some damn stupid things also, so....

 

[skahtul]

I had some good prints, and some not so great. Both of these parts were at the same 45-degree orientation with the edge pointed at the bed. One came out great, the other did not.

I at least have a clean edge and the gap is not too bad, but this second part is not usable as it's warped and distorted:

Right now I am attempting the 'tons of supports on the bottom' and printing it 90 degrees straight up. We will see how that works out.

 

[skahtul]

Here is a test print of the 1:400 scale with PLA, now this would be a huge print!

 

[Firefox3D]

I at least have a clean edge and the gap is not too bad, but this second part is not usable as it's warped and distorted:

Can you show how the second part was orientated with a screenshot, I think I know what's going on.

 

[skahtul]

Can you show how the second part was orientated with a screenshot, I think I know what's going on.

Sure thing! Here are both sides:

 

[Firefox3D]

Ok, I think it's a combination of the long thin edge with the many small supports causing it, could be partly caused by resin starvation as well.

It might not be possible but if can you orient it so the corner is facing the bed so it starts printing with just the corner, and/or double the point size and half as many supports.

 

[skahtul]

Ok, I think it's a combination of the long thin edge with the many small supports causing it, could be partly caused by resin starvation as well.

It might not be possible but if can you orient it so the corner is facing the bed so it starts printing with just the corner, and/or double the point size and half as many supports.

Okay, we are printing now! Thanks for all the feedback, it has really helped me get some great prints. I ran out of resin a while ago so this was paused for a few days but that is all in the past now