HMCS Windsor - Upholder class 3D print - files from Nautilus DD

[RanSan]

Thanks, Bob, I appreciate you taking the time to clarify this and to look out for the artists.

For my part, one of the main reasons I started creating these files was to give people access to boats that might otherwise never be available as RC models. There are a lot of interesting, obscure, and historically significant submarines that simply aren't commercially produced in RC form, and I really enjoy being able to bring some of those designs to life and make them accessible to the RC community.

I’m glad to see them being enjoyed by the RC community.

[SubSteve]

Rudder of sistership HMCS Victoria

[NavyShooter]

OK, so, trying to move on....looking at my options for a watertight cylinder, and I think I'm going to try and make my own.

I found this option at Amazon for a tube - should I get 2mm thick or do I get a thicker tube?

https://www.amazon.ca/gp/product/B0CYHCX8DF?smid=AAZIZVY2NCX3Z&psc=1

[NavyShooter]

Also, I created this sub display stand - It was something that didn't come with the print files.

If anyone wants copies of the print files, let me know.

[NavyShooter]

Based on the dimensions given above, I'm working on watertight cylinder end caps now. Tinkercad is a simple program, but for stuff like this it's quite handy.

Here's my first go - should fit in a 70mm OD 66mm ID (2mm wall) cylinder, and accept 66mm O-rings (using 2 because...why not?)

One has a central hole for the shaft. I'm thinking of drilling the other holes.

Print ABS and add a layer of epoxy to seal them completely?

[trout]

I would print with all the holes in the escape and drill out to the correct size if needed. You may need to print a couple of times to do minor adjustments for shrinkage and o-ring fit. You will want the right squish to fit the tube. I personally like 1/8th inch o-rings, but have used 1/16th inch.
it is a fun adventure you are on!

[Subculture]

O-rings will typically be dimensioned on their inside diameter, assuming you purchase from a reputable supplier, so you add on the o-ring cross section twice to get full outer o-ring diameter. So for your example a 66mm o-ring with say a typical cross section of 3mm will be 72mm diameter overall- too big when using radial compression. You would want an o-ring of 60mm or lower for 3mm cross section rings. There is some tolerance with o-rings, but they shouldn’t be too loose or too tight to get a good seal.

Getting the right seal is not art it’s science, assuming your printer is accurate if you dimension the parts right you’ll nail it first time,

You should pay close attention to the end cap groove depth and width, the depth allows sufficient squish and the width allows the o-ring space to extrude as it squish’s, that last part is often overlooked. I aim for 10% of o-ring cross section squish sometimes less, o-ring supplier often specify up to 25% squish, but this will give the o-rings a hard life and make endcap removal difficult.

I would use a minimum of 3mm or 1/8” o-ring cross section, but use a single o-ring rather than two. Extruded tube tends to have a poor internal tolerance and a thicker o-ring is both stronger and gives a bit more tolerance.

Make sure you chamfer the edge of your tube to avoid the cylinder chafing/cutting the seal.

I would also make your end cap outer edges larger than the cylinder if you have room in the boat, and consider printing some kind of knurl pattern on that part. Will make them much easier to remove in the field.

Good guide on designing for o-rings https://www.parker.com/content/dam/P...e/ORD-5700.pdf

[trout]

Andy, good advice! I always enjoyed your you-tube on turning your own end cap.