filming window in Duck Punt - brain pick

dylanwinter

dylanwinter

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www.keepturningleft.co.uk
Since I started sailing the duck punt I now realise that you get the best out of it if you sail it on its ear - -with the water close to the waterline gunwhale.

The other day some-one posted an image of a big yacht tight reaching with the leeward portholes almost under the water

as a cameraman I also realised that what I want to do is to film across the tops of the vegetation - not straight down through it.

The boat is made from 4 mm ply

I am planning to get some perspex and get a man to mill the edge off to the thickness of the ply so that it has a lip maybe an inch wide

I am then going to cut a hole in the side of the boat to match the inner dimension

push it into place on a bed of epoxy or mastic and then put epoxy take around the outside

this version is not going to be pretty

as a cameraman I want the window to be as big as I can make it

as a sailor I do not want that to become a weak point on the boat


this is the quick and dirty test bed to see if a window works

I like the punt so much that I am going to build a nicer one next winter - I can make it ligher, stifferer, more comfortable and more bouyant with uouyancy tanks fore and aft

exactly the same hull shape and rig though b ecause it sails so well

this will determine if I build a window into the next one

A4 size 6mm perspex sheet from here

http://www.ebay.co.uk/itm/Clear-Acr...t=LH_DefaultDomain_3&var=&hash=item76c18b1910

£4.70

I am going to just put the window on the port side - I can steer with my left hand and film with my right

the flip out viewfinder will be towards me

I am going to cut a hole smaller than the A4 and then attach the perspex with this sort of pungent transparent mastic

http://www.ebay.co.uk/itm/PLUMBERS-...DIY_Materials_Plumbing_MJ&hash=item45fc6f7111

I will then drill holes through and put countersunk nuts and bolts from the outside with washers on the inside of the boat to spread the load.. If oucntersingling is not a good idea I can put simple slot head bolts through - more turbulance.... but not much

that will avoid weakening the perspex compared to a countserink

how big an overlap do I need is one inch enough

is 6mm the right thickness

how far apart can the bolts be

one in each corner and a single one in the middle of the short sides and two along the long side

10 bolts in all

will this keep the water out?

will this work

can I get by with thinner perspex

Dylan

http://www.youtube.com/watch?v=y_qFvMbrMWw
 
Last edited:
Have you tried focusing the Xacti through perspex and water? I suspect it could keep alternating focus between the perspex and the river bed depending on the available light. I've noticed this if I film through a window.

I'm pretty sure that thinner perspex could work - it only has to keep the water out and there is almost no pressure as it is barely below the surface.

I think I would utilise the waterproof qualities of the Xacti and immerse it directly in the water as it has an exposure mode to deal with that. Maybe make a mini "shark cage" to protect it from groundings.

I'm looking forward to seeing the results!
 
bigger camera

planteater said:
Have you tried focusing the Xacti through perspex and water? I suspect it could keep alternating focus between the perspex and the river bed depending on the available light. I've noticed this if I film through a window.

I'm pretty sure that thinner perspex could work - it only has to keep the water out and there is almost no pressure as it is barely below the surface.

I think I would utilise the waterproof qualities of the Xacti and immerse it directly in the water as it has an exposure mode to deal with that. Maybe make a mini "shark cage" to protect it from groundings.

I'm looking forward to seeing the results!
Click to expand...

my plan is to use the bigger camera

I can control the focus and it also does a much better job with the light than the Xacti

also when the xacti is under water you cannot see the viewfinder.

so can I go to 4mm

d
 
Rather than use perspex, I would be down the local car yard and find a small window in tempered glass. Hold it into the recess with an ally bezel and sticky goo. Lots of the small vans have rectangular widows just aft of the doors to aid visibility. One of those might do.
DW
 
DownWest said:
Rather than use perspex, I would be down the local car yard and find a small window in tempered glass. Hold it into the recess with an ally bezel and sticky goo. Lots of the small vans have rectangular widows just aft of the doors to aid visibility. One of those might do.
DW
Click to expand...
I would suggest the same. Perspex will scratch up ever so quickly, more so than glass.
 
good plan - but

DownWest said:
Rather than use perspex, I would be down the local car yard and find a small window in tempered glass. Hold it into the recess with an ally bezel and sticky goo. Lots of the small vans have rectangular widows just aft of the doors to aid visibility. One of those might do.
DW
Click to expand...

that will be very elegant - but also heavy

not sure if I will get the rubber seal out just in one peice and back in again

I am passing a junk yard today - going to have a look though

thanks for the suggestion

D
 
Dylan,

as someone who used to play with camera pods on aircraft a lot, I think Planteaters' concerns are valid.

Can you manually overide the focus ?

A thought; there used to be 'candid adaptors', working on the same principle as a periscope with a mirror in front of the lens at 45 degrees, so one was pointing at 90 degrees from what one was actually filming.

Such a gizmo - I wouldn't think too difficult to DIY - would allow you to have the camera in line with the hull, not sticking out athwartships ready to get kicked etc, possibly opening a hole in the side !

If really serious, some sort of aimed lighting from the punt bottom may also be an idea ?
 
I'd suggest using thinner polycarbonate sheet rather than acrylic sheet such as perspex, after all if it's tough enough for crash helmet visors it should be tough enough for a hull window. Also it might be worthwhile doubling the thickness of the plywood around the window to reduce stresses in the hull at the window corners.

I'll bet you still don't get to see the seals feeding though!:)
 
good idea

PaulJS said:
I'd suggest using thinner polycarbonate sheet rather than acrylic sheet such as perspex, after all if it's tough enough for crash helmet visors it should be tough enough for a hull window. Also it might be worthwhile doubling the thickness of the plywood around the window to reduce stresses in the hull at the window corners.

I'll bet you still don't get to see the seals feeding though!:)
Click to expand...

aha

you mean this stuff

http://www.ebay.co.uk/itm/4mm-Green...den_Structures_Fencing_CV&hash=item4cfc1f6fef

looks cheap and available

can I drill it - is it tougher than perspex or acrylic

D
 
Much tougher than perspex. Riot shields are made out of thicker sheets. But, same problems with scratching. You can drill it. About the weight of car windows, many are only 3mm thick, so not very heavy.
 
Definitely not polycarbonate twinwall Dylan - it isn't transparent! Also its more like corrugated cardboard and the plastic sheet it's formed from is really much less than 1mm thick.

I reckon something like this would be suitable:-

http://www.ebay.co.uk/itm/2MM-CLEAR...924?pt=LH_DefaultDomain_3&hash=item5d2aa35d94

By the way, another way to reduce the weakening of the hull would be to make the hole with radiused corners
 
I can live with scratches

DownWest said:
Much tougher than perspex. Riot shields are made out of thicker sheets. But, same problems with scratching. You can drill it. About the weight of car windows, many are only 3mm thick, so not very heavy.
Click to expand...

I can replace the window if it gets scratched - bit it is not in the bottom of the boat - it is in the side

Dylan
 
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