1/32 Fiat RS.14

[AlexM]

Thank you all for your kind comments!

For the moment, I must say that I don't follow the goal to make this a real kit. After some consideration I realized that this is above my skills. It would need some investmenst (last but not least commercial software licence), and the short time I find for modelling, I want to focus on my own projects

The cleas nose was just the fist pull, and will be replaced by a hopefully more clear part. The plug for vacuforming was sanded smooth after printing. It was printed with white HIPS (High Impact Polystyrene), which is relativly soft and easy to sand. A way to further smoothening the plug can be seen on the right. This black part was printed some time ago by a printing service, before I bought my own 3d-printer. It is printed in ABS. I also sanded it smooth, and diped it for just a second into aceton. The aceton melted the surface and turned it shiny after drying.

 

[AlexM]

Talking about the fuselage parts, I'm still in the learning phase The approach for the RS.14 has its problems.

 

First the CAD-work is pretty "labor intensive" as the fuselage halves haves have to be made twice (outer and inner surface). The outer shape can't just be copied and slightly scaled down, as the wall thickness would then be inconsistent. And then follows the actual interior structure, which is laborious too.

Then, the actual wall thickness must be considered. On my RS.14, it varies from normally 1,5mm to 1mm at areas with openings, to come more close to scale thickness while keeping stability. From what I know now, it would have been better to choose a multiple of the printing nozzle diameter (0,4mm), when printing the fuselage perpendicular. For example 1,2mm would be good. With 1,5mm, there is a slight air-gap inside the wall, what leads to less stability.

And finally, even with a 3d-printer with two printheads, it is very difficult to print the fuselage parts with clean interior details. Especially the corners of the interior frames are very difficult to clean up.

 

Therefore, on future projects, I'll try a different approach. Here, I just made the outer surface, and printed both parts as one object, with a small recess line between, where the two halves could be cut apart. The whole part can be printed as a hollow object, and the wall-thickness can be easily adjusted in the printing software (here 1,2mm). All interior details have to be made “conventional†with styrene profiles.

 

[brahman104]

Thanks for the info on the vac forming Alex, I'll have to give it a try sometime.

 

I know exactly what you mean about the fuselage design. I encountered all the same problems with my B-17. I agree with you about the wall thickness, as I made mine 1.5mm as well, but I will correct this for future designs. 

 

My printer only has one print head. What is the advantage of the second? 

 

I also did what you have done here and made a "sacrificial" former that provided good surface area contact on the print base, as well as hopefully retaining the cross-sectional shape of the fuselage.

 

Good to see someone else having a go with major fuselage parts!

 

Craig

[AlexM]

Hey Craig, maybe once we will have a CAD group build in the future

 

With two printheads, you can use different colored materials and get interesting results like here:

https://all3dp.com/colorful-dual-extruder-3d-printer-models/

 

I haven't tried this myself yet, as I prefere Spits and 109s rather than sweet Pokemons and pumpkins   

 

Another interesting feature is the use of completely different materials with the second printhead to create support structure. A 3d-printer can't turn off the laws of physics, and isn't able to print into the air. For overhangs, it needs something to print on (exception for some cases: bridging). The printing software can automaticly create support structure onto which the actual object is printed. The support structure is slightly connected to the actual object, and normally has to be removed with gentle violence at the end. But now there are water soluble materials that can be used with the second printhead for support structure, what leads to interesting posibilities, like shown in this promo video:

 

https://www.youtube.com/watch?v=oeJLLC2NJQs

 

Cheers

Alex

[brahman104]

 

 

I haven't tried this myself yet, as I prefere Spits and 109s rather than sweet Pokemons and pumpkins    

 

Hahahaha! Very true Alex

 

Ah yes I see why that would be an advantage. The software in mine is generally pretty good with its support structure, and most of it usually comes off without too much trouble. I've only used ABS so far, as I've heard PLA tends to break down over time.

 

I'm closely following the development of the Formlabs Form 2 resin printer, as they seem to promise much in the way of fine detail. However for large objects such as you are doing here, I still believe our respective machines are the way to go.

 

You've been doing an amazing job so far. I can't remember if I asked you before what software you use for your CAD work? I've had good success with Rhino3D so far.

 

Cheers,

 

Craig

[SCRATCH BUILDER]

Hey  Alex,

 

If you can get Simplify 3D for you printing software, great software. Like have said before I us Blender software for designing, it will let you select you overall thickness and you are able to split the fuse's to print as two separate objects.  I run a .40 nozzle and can print .40mm wide and a layer height as low as .05mm, I run at a print speed of 30mm/s which greatly improves your prints. Must printers can run at 60mm/s but the results are less then great, if you have time to let it print, slow you speed down.

 

But anyway it looks like its coming along just fine, Need any 3D printing help just shout out!

[AlexM]

Hahahaha! Very true Alex

 

Ah yes I see why that would be an advantage. The software in mine is generally pretty good with its support structure, and most of it usually comes off without too much trouble. I've only used ABS so far, as I've heard PLA tends to break down over time.

 

I'm closely following the development of the Formlabs Form 2 resin printer, as they seem to promise much in the way of fine detail. However for large objects such as you are doing here, I still believe our respective machines are the way to go.

 

You've been doing an amazing job so far. I can't remember if I asked you before what software you use for your CAD work? I've had good success with Rhino3D so far.

 

Cheers,

 

Craig

 

I'm still using Sketchup with some aditional extensions to make it suitable for tasks like a fuselage (with its basic features, this software is defenitly not suitable). I like it as find it easy to use. I once tried the free trial Rhino, and got the impression that it is way superiour to Sketchup. But I was also a little bit overwhelmed (better say: very overwhelmed).

As long as I cope with Sketchup for my projects, I will keep what I am familiar with

 

A machine like the Formlabs Form 2 seems indeed interesting as a secundary printer for small detailed parts. But the resin costs are pretty impressive. 160 € to 450 € for one liter of resin? Seriously?

 

I wonder if that machine is already suitable to make a aceptable radial engine with fine cylinders

[AlexM]

Hey  Alex,

 

If you can get Simplify 3D for you printing software, great software. Like have said before I us Blender software for designing, it will let you select you overall thickness and you are able to split the fuse's to print as two separate objects.  I run a .40 nozzle and can print .40mm wide and a layer height as low as .05mm, I run at a print speed of 30mm/s which greatly improves your prints. Must printers can run at 60mm/s but the results are less then great, if you have time to let it print, slow you speed down.

 

But anyway it looks like its coming along just fine, Need any 3D printing help just shout out!

 

Hi Rick,

 

until now, I never thought about the printing speed. Just checked the printing software (Cura), and its default setting is 70 mm/s. Apparently rather high. I'll once try a lower speed just for test.

 

How do you handle ABS and persuade it not to warp, and to stick on the printing plate?

And how to prevent tension cracks when printing higher objects? This ouccured for example when I tried to print a Float for the RS.14 with ABS.

 

Cheers

Alex

[brahman104]

 

 

I once tried the free trial Rhino, and got the impression that it is way superiour to Sketchup. But I was also a little bit overwhelmed (better say: very overwhelmed).

 

Hahaha, yes I hear you! It is a very powerful program and I'd be lying if said I understood even a fraction of it, but through doing I have learnt. Tim (Wunwinglow) is an expert on the program if you are ever interested in looking into it again and Peter (Airscale) has been able to produce some amazing results as a "novice" (cough cough ).

 

Yes the cost of the consumables does seem excessively high for those machines and I'm still not convinced of the level of detail you can get looking at photos on line. I would argue you could get many parts printed through Shapeways at a very high level of detail before you broke even on what it would cost for the Form 2, so I'm still waiting and watching. I think in time it will get there, but perhaps not yet.........

 

Scratchbuilder raised a very good point which I had not considered before about the print speed. I'm not even sure I can change that on my machine but I'll have to look into it. I printed a horizontal stab and elevator for my B-17 the other day without any problems and they are a bit over 150mm high. Perhaps just due to the pure volume of your float there was too much cooling within the piece. Did you do it solid or with a void in the middle?

 

The lifting from the bed issue I guess depends on your machine. For glass beds, I have seen people use some kind of tape and cover it with a slurry made of ABS prior to the print. My machine has a heated bed, which I always let get to 80 degress C before I start. I still get a little lifting, but the raft underneath tends to "absorb" the lifting before it gets to the part. Orientation is a massive factor in 3D printing as I'm sure you're aware.

 

We should probably make a single topic about 3D printing tips for all our trials and tribulations now there seems to be a few of us doing it!

 

Cheers,

 

Craig

[Starfighter]

Alex, I am following your build since the beginning and I am blown away - you're doing some stellar work! 

 

The resin prices for the Form2 have raised quite a bit since the printer hit the market, but it's still the best "affordable" (yet not for me) desktop printer on the market. I am happy to have one on my desk at work... If I had the funds, I'd definitely buy one. 

Edited September 5, 2017 by Starfighter

[SCRATCH BUILDER]

Took Craig's advice and started a 3D print thread here - 3D Printing

Edited September 5, 2017 by SCRATCH BUILDER

[Jim Barry]

I somehow missed some of the newer updates. Just wanted to chime in and cheer you on. This is so nice, Alex.   Gosh it's just about caught up to the Hampden now (or even passed it).  I feel for you having had Bearcat/Fury attention span issues all this year. I must say it is nice to just have one now, though.  

[AlexM]

Oh yes, there is still that Hampden, looking at me with envious glance for being ignored by me for quite some time. Those navigation lights make me sick  

I should have thought about the lights earlier bevore painting, and probably the whole thing would be finished already.

[AlexM]

Hello there, little update.

 

I made the interior framing of the nose. Unfortunately, my Ultimaker 3d-printer isn't able to create such fine structures, with some frames with just about 0,8 mm width. Therefore it was made by a printing service I found on www.3dhubs.com. It was printed with a machine called Draken from 3dFacture. I'm very pleased with the result. Removing the support structure was somewhat tricky.

 

 

 

Cheers

Alex

[holzemjo]

So cool!