Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Tutorials & "How Tos" ... => Topic started by: GG on September 08, 2019, 02:58:00 pm

Title: Working Cowl Vents
Post by: GG on September 08, 2019, 02:58:00 pm
cowl vents are one of those items I often prefer to buy rather than make, well assuming that suitable shapes and sizes are available.  On electrically powered model it matters not if the vents are solid, they are there just to add to the model's appearance.  However, faced with the need to get as much fresh air as possible inside a steam powered model of an early TBD (Torpedo Boat Destroyer) some functional vents were needed.

No suitable ready made vents could be found so I would be forced to make the damn things.  Luckily, the contents of one of Mrs Guests kitchen drawers came to my rescue.  Amongst all the knives and other implements, of which I admit little idea of their functions, were a set of plastic measuring spoons.

My immediate thought was that they would make perfect tops for the cowl vents.  This was quickly followed by the realization that I would never get away with "borrowing" a few from the drawer.  Luckily, a couple of cheap sets of various size measuring spoons could be bought from local shops.

Back home and the bowls were cut away from the spoon handles, holes made for the tubes and they were stuck together.  A little sanding was needed to blend the tubes to the inner bowl surfaces, a lick of paint and the TBD model had its working vents.

It is such an obvious thing that I'm sure others must have done it before.  It is also an example of how pushing a problem to the back of your mind but keeping your eyes open, will often locate a solution.  This approach makes life tolerable when Mrs Guest takes me into shops I would never normally enter.  I just wander around thinking "there has to be something in here that can be used in a model".

Glynn Guest
Title: Re: Working Cowl Vents
Post by: Capt Podge on September 08, 2019, 03:07:57 pm
Simple yet brilliant solution Glynn. That's another one for the 'good ideas' book - thank you for sharing  :-))

Title: Re: Working Cowl Vents
Post by: RST on September 09, 2019, 08:43:34 pm
Nice result and ping-pong balls etc!

I use the plastic sheets "pills" like asprin / paracetamol come in for things like this also -just have to remember to use a fingernail etc to cut the foil and not to push the pill through and cut the plastic.  Admittedley not the easiest to remember when you have a headache.

I saw something on this before.  I suppose maybe it was even the measuring spoons!  Question is, how quick were you to replace them because you usually have to factor in a domestic at some point ha ha.

...One question -on that pic with the ali(?) main tube it looks like there's not much area for the glue to hold.  What glue did you use.  Kitchen utensils are renowned to be non-stick / low surface energy which makes them difficult to bond on small areas.  Or they hold fine for 6 months, then fall-off of their own accord.

I must admit, slowly learning 3-D printing with a dirt-cheap printer and things like this are becoming rediculously easy to reproduce when more than 2 or 3 identical twins are required, as long as the geometry isn't too complex.

Title: Re: Working Cowl Vents
Post by: GG on September 10, 2019, 09:24:46 am
        Only having to deal with powders, I suspect these measuring spoons were made from cheap polystyrene.  And so, very easy to stick to anything.

Title: Re: Working Cowl Vents
Post by: Geoff on September 16, 2019, 01:16:53 pm
Another way to make these vents is to soften some plastic card over a flame or in the oven, hold it over a pipe of the right diameter and press a ball shaped object down. This will form a semi-circular shape which can then be trilmmed to shape.  The ball needs to be a rattle fit in the tube to allow for the thickness of the plastic card sheet. The advantage is that using styrene you can then glue/weld the tube and cut out the hole.

With steam I also found that it may help if some of the vents are pointed the other way as this allows exhaust air to leave and assists in freassh air being drawn in.