RC Benchy

[ddmckee54]

I don't know if I'd exactly call it a boat or not, it's ugly enough to be cute. I stumbled across an RC version of Benchy on Thingiverse. If you're not into 3D printing. Benchy is used to benchmark how well your printer is performing, hence the name Benchy. That version of Benchy is only a couple of inches long, the RC version is about 8 times bigger. The print files were on Thingiverse, and as soon as I quit laughing I told myself that I gotta build on of those. Somewhere I even saw a picture of somebody that had built a version with one of the Mario Bros. as the captain.

This is about where I'm at on this project. I hope this works, I haven't had a lot of luck posting images on this site.
https://lh3.googleusercontent.com/pw...-no?authuser=0

I've reprinted the bow section which isn't in the picture, and the blue hull section. That section had a layer shift that I finally figured out what was causing it to happen. The blue section you are looking at was the 2nd attempt and the layer shift occurred at about the same place both times. It was also too big, I thing I fat-fingered the scaling factor. The 3rd time printing that part was the charm, came out looking GOOD, and it fits perfectly.

The Thingiverse files give you the option of building Benchy as either a tugboat, or as a fishing boat. I was talking with one of the engineers that I work about the RC Benchy, and he christened him "Dreadnought Benchy", the name stuck. I'm going to build RC Benchy Option #3, the heavily armed tugboat version. He's got to be able to defend himself doesn't he?

Don

[Zabco]

I was at my local Micro Center store about a month ago. They now have a large section of the store dedicated to 3d printing and usually have 8 to 10 printers running at any one time printing various doodads and whatnots just to demonstrate what they can do. Their largest printer was just finishing up printing a scaled up version of Benchy. This was identical to the small version used for testing but BIIIG. Was probably 8 to 9 inches long. Looked pretty darn good. I'd hate to have to guess how long it took to print or how much plastic went into it. Wish I had snapped a photo of it.

[ddmckee54]

The RC Benchy from Thingiverse is a little bigger than that, it's about 15" to 16" long, and 7-1/2" to 8" wide. It's probably about 12" tall, I never measured it.

I built a prototype for the turret two nights ago. But after setting it on the deck last night, I realized that it's too tall. Last night I redesigned the turret, I took 15mm out of the height. If I take much more out of the turret height the barrel on the forward turret won't clear the railing in the bow without elevating. I can currently get about 45-50

[ddmckee54]

There was SUPPOSED to be more to the above post, don't know what happened to the rest. Oh well...

I got my Weldon #4 order an Friday, and Benchy is starting to come together - literally.


As you can see Benchy's hull is one piece now, it's not water-tight yet but it's one piece. He also has his V8, and in the process grew some TEETH. There's a whole lot of sanding to be done before the hull's ready for paint.

Don

[ddmckee54]

A lot of sanding has been done to the hull, it's just about ready for primer, and sanding, and filling, and sanding, and more sanding. Then there's the pilot-house, and the turrets, and the gun barrels, and... Did I mention more sanding?

[jerry56]

That's the only draw back to 3D printing...

[ddmckee54]

Originally Posted by jerry56

That's the only draw back to 3D printing...

That and the print time. The 2 main sections of the hull take about 28-30 hours to print - EACH. I had to print the forward section 3 times before I got a good part.

I THOUGHT I had a brilliant idea to seal up the hull and reinforce it a little at the same time. I was going to use a thinned version of my glue/filler goo and tissue paper, similar to the dope/silkspan covering on the stick and tissue model airplanes that you may, or may not, have built as a kid. Turned out my brilliant idea was more of a brain fart. The Weldon #4 solvents evaporate so quickly that the tissue didn't have much stick-to-it-iveness, and peeled right off.

After that I decided that I needed to go Old-school to seal up the hull - I varnished it with interior/exterior varnish. I spent the rest of the weekend sanding, and varnishing, and sanding, and varnishing, and sanding, and varnishing. The hull now has a mostly blemish-free semi-gloss finish. There's still a couple of minor divots that may or may not get filled when I get to the priming and painting stage. This IS a tugboat after all, it NEEDS a couple of scars.

Don

[frizzen]

Looks like good progress!

Dreadnaught shouldn't even fear sinking.
I was going to ask if the hull might let you put some styrofoam anywhere in there? Or does the support matrix try to seal it up into little airtight chambers well enough to float even when swamped?

[ddmckee54]

Frizzen:

I haven't tried floating this thing yet, there's still a couple of major holes below the waterline. Benchy's still missing his prop shaft/bearings, and rudder tube. I think it's going to take a fair amount of ballast to get this thing down to an appropriate waterline.

Benchy looks pretty massive, but between the rub rails and the deck the hull thickness is only about 0.6-0.8mm thick. It's a total of 2 perimeter walls thick. The rest of the hull is probably 1.0-1.2mm thick, it's a total of 6 perimeter walls thick. The thinnest part of the hull is on the keel in the bow section. There the shape of the interior and the exterior of the hull required infill, so the hull wall at that point is only 3 perimeter walls thick. Overall, the hull walls are probably more than 95% solid.

If the waterline is where I think it is, the barely visible horizontal line in the picture, I'll have about 1" of freeboard between the waterline and the scuppers. There's a lip about 1/4" high around the access hatch in the deck.

There's a pond in the city park behind my house, probably used to be a mill-pond, that's where I sail my other tugboat. I'm a fair-weather sailor so I'm not worried about waves swamping the boat. Besides, the pond's only a couple of feet deep - DAMHIK.

Don

[ddmckee54]

The needle files, the scrapers, the wheel, and myself all have spent a little quality time together for the last couple of nights. I've got the layer lines removed from most of the wheel, should be able to finish it up tonight. The pilot-house is about as smooth as it's gonna get, not much left except the turrets, gun barrels, and pilot-house roof. And the yet to be designed CWIS and exhaust stacks. (And maybe a captain at the helm figure.)

[ddmckee54]

I haven't been able to find a Cap'n Crunch figure in an STL file, licensed trademark and all that. I did find the STL files for Mario on Thingiverse though. Why I can find Mario, and not the Cap'n I don't know.

Mario's supposed to be 11cm tall, which I thought was about right. I downloaded the files and printed out a couple of the major components. I think at the 100% size he's going to be too small. I'm going to print out enough parts at this size to determine if, and how much, I need to scale him up. I've still got to print out the shoes, the neck area, and the hat. Then I can glue him together and know for sure if he needs to be scaled up.

The files are split up so that you can print them in the correct color of plastic to get a realistic Mario - how's that for an oxymoron? I don't have the flesh color, or the brown, and I'm not going to buy a roll of each for just this one print. I'll just print the parts in one color and then paint them the correct color.

He LOOKS pretty good, I've just got one gripe about this model on Thingiverse. The "Download All Files" button doesn't, it just takes you to the files page where you wind up downloading each file individually. There's a LOT of parts to this guy, 35 of them, to be able to print him multicolored - kudos to the designer.

Don

[ddmckee54]

Take a look at this and see what you think, has Benchy got a Cap'n? (I think so.)
https://lh3.googleusercontent.com/pw...-no?authuser=0

Here's a slightly blurry side view.
https://lh3.googleusercontent.com/pw...-no?authuser=0

I printed Mario out at 100% and stuck him in the wheel-house, he was just too small. I reprinted this version at 120%, which I think looks a LOT more better. I think he's going to have to go under the knife and have a little surgery on his right arm though. To make it look more like he's holding the wheel, and less like he's just standing there like a Dork.

Benchey got several other modifications. He got his Close In Weapon System, his smoke-stack was modified to be a radome, and he got his diesel exhaust stacks. I originally had a really neat set of barrels designed for what was supposed to be a Mini-gun. I took one look at the printed version, realized that they were WAY TOO SMALL, and said - "Nope, not gonna happen." The Mini-gun then got replaced with the chain-gun seen in the picture. As you can see this is not just a Close In Weapon System, it's a REALLY Close In Weapon System. In fact it could be used to pick-off the seagulls and keep them from crapping on top of the turret. I've got some seagull figurines on order to set up just such a scene.

I've got to get some more hardware, motor, ESC, prop, bearings, prop-shaft, rudder-post, and all the other Bit's and Bob needed to make a functional boat - that I haven't already got stashed away somewhere.

Then Benchy will be almost ready for the test pond, and his weights and balance testing. Painting will be done after that.

Don

[frizzen]

It's looking good with Mario.

Are you going to put in some movement on the Bow Gun? Having it setup to traverse while under power could look pretty cool.

Mario might need to be careful, i hear there can be pirates around these parts
https://cults3d.com/en/3d-model/various/cap-n-crunch
Or there were a couple action figures

"Look at me, look at me. I am the captain now."

[ddmckee54]

Frizzen:

Actually since I work where Cap'n Crunch is made, it was STRONGLY hinted that the Cap'n should BE the captain of Benchy. I saw that version of the Cap'n, unfortunately I don't have the software or the talent to sculpt the rest of him. I couldn't find any usable STL files of the Cap'n. One of the engineers that retired from here collects Cap'n Crunch memorabilia. He's going to look and see if he's got anything usable that he can scan for me - no luck so far.

I did find the STL files for Mario though. His left hand almost looks like he's going to pull the chain for the horn - at least that's my story and I'm sticking to it. With a little surgery I think I can get his right hand to look like it's on the wheel, or at least spinning the wheel.

I'm halfway thinking about turning the CWIS into a squirt-gun in the future. I may also need to add another CWIS for the aft half of the boat. The damned seagulls have found out that they can crap all over the aft turret, and Fire-Control can't do anything about it. (Stupid radome. Besides, I've got 3 seagull figurines coming and I only need 1 for the forward turret.)

Don

[jerry56]

This project is so cool....I can't wait to see how this turns out...

[ddmckee54]

Mario is out of surgery and recovering nicely. His time under the knife wasn't too drastic. I just bent his arm a little, and twisted it a bit. Just enough so that he doesn't look quite so much like he's the Fonz going Heyyyyyyy. I'll get a little filler on his arm, enough to cover the scar and give him a bit of an elbow.

Don

[ddmckee54]

Mario's surgery was done the old fashioned way, with saw and filler. I just amputated his arm at the elbow and then reattached it. I think it turned out OK. Here's a couple of views of the wheelhouse, this first one is from forward looking into the wheelhouse.
https://lh3.googleusercontent.com/pw...-no?authuser=0

This next one is looking at the port side. I plan to attach a chain to Mario's left hand to make it look like he's going to sound the horn.
https://lh3.googleusercontent.com/pw...-no?authuser=0

This last one is looking at the starboard side. I didn't get too crazy with how much I bent his arm, wasn't exactly sure where his hand would wind up in relation to the wheel. I think it looks OK.
https://lh3.googleusercontent.com/pw...-no?authuser=0

Don

[frizzen]

Mario is looking a lot more at home in there!
(But now i kinda want to see a greaser Mario leaning against a juke box.)

Atleast i'm not feeling as much urge to suggest Steamboat Willie piloting a dreadnaught...

[ddmckee54]

Benchy's temporarily on the back burner while I wait for parts to arrive.

You know, the unimportant stuff like the motor. an ESC, the prop-shaft and bearings, the prop, more servos - little stuff like that. I got the motor yesterday, and the servos a day or two ago. The prop-shaft and its' bearings aren't supposed to get here for another week or two.

I'll have to find something else to do until then, probably yardwork. It is getting to be that time of the year again.

[ddmckee54]

The parts have started arriving. I got the motor and the prop shaft earlier, and last night I got the ESC. I got the motor installed, and the shaft fitted ready for installation. The connector was a 3mm x 3mm, I needed a 3mm x 1/8". It was a solid coupler anyway, so I've got a Huco U-joint ordered. The ESC had NO connectors, so now I've got to source some connectors, get them ordered, and installed. The prop shaft came with a useless, too small, 2 blade prop - which I knew about. So I ordered a 3 blade in the size I wanted. The 3 blade prop is apparently on a different slow boat from China.

I've got to find my 3mm brass rod and my 4mm brass tubing, they're stashed SOMEWHERE. I can get the rudder installed when I find them. When that's done all the holes in the boat should be plugged. Then it'll be weight and balance time? (And checking to see if all the holes in the boat ARE plugged.)

Don