1/20 Project дельфин, 3D printed

[eckloss]

The hull sections are 5mm think. I'm printing everything with 25% infill to add rigidity. The larger pieces do have some flex to them but nothing near enough to really affect the boat overall.

[eckloss]

First attetmpt at decking is done. I've gone back and edited each section to include some more detail. I'll be printing them again over the next few days.

[sam reichart]

thinking about this hull, and the Seehund that Bob has; how easy is it to sand off the "ridges" in 3D printed objects?

[eckloss]

Sam... depends on how much you do. The low ridges are easily knocked down with 80 grit and then larger grits to get it smooth. In the picture below, just a surface sanding will still show the large ridges you can see, albeit rounded off a bit. You can take it down further, but you start to risk sanding through the top layer. The parts are printed with two outside layers, and, in my case, a honeycomb pattern of filler in-between.

[sam reichart]

Sam... depends on how much you do. The low ridges are easily knocked down with 80 grit and then larger grits to get it smooth. In the picture below, just a surface sanding will still show the large ridges you can see, albeit rounded off a bit. You can take it down further, but you start to risk sanding through the top layer. The parts are printed with two outside layers, and, in my case, a honeycomb pattern of filler in-between.

[ATTACH=CONFIG]6863[/ATTACH]

ah...gotcha.
so, if wanted a slick surface hull, like you'd see in an injected molded model, you would have to have a printer that has a higher(?) tolerance? which is where, I'm assuming, prices for that level of print perfection go though the roof...

[JWLaRue]

Sam,

Part of the 'ridge' or layering problem can (also) be minimized or eliminated depending on the print orientation. That's something that can be addressed when the 3D model is 'sliced' into pieces for printing.

-Jeff

[sgtmac1]

Will you be using high fill primer to smooth out the ridges? And CA to glue it up?

[eckloss]

I found that the Plastruct Bondene works very well on PLA. Provides a true weld rather that just a glued joint as with CA.

And yes, I will be using high build sandal primer. But I may not need as much as I originally thought. It's sanding smooth very easily.

[sgtmac1]

Thanks. Now for the latest rumor-PLA will dissolve in water. True or false? I sure hope that is just somebody mouthing off after I spent $550 on my 1/72 sub...

[eckloss]

That's PVA, not PLA. You have no worries.

[JWLaRue]

However, PLA will absorb water. Not a lot and not very quickly...but it is something to be aware of.

For R/C submarines this shouldn't be a problem given the duty cycle that our boats typically go through.

-Jeff

[thor]

Paint does have a tendency to lift on PLA after multiple exposures to being submerged in water. Make certain to seal any painted surface well and you should be ok.

[eckloss]

Finishing up the last of the deck, stacks, piping, and torpedos. That just about concludes the bulk the printed parts. Next come the WTC saddles and such.

[salmon]

Coming along! Maybe I missed it, what system are you going to put in it?

[eckloss]

That's a very good question. I've been leaning towards this just being a surface runner, so if I stick with that, a 3.5" tube for all the gear and battery.