Adding a pidgeon box

[MtB]

There's a boat we've seen that we like and it seems probable that we'll buy it. Being all portholes it's a bit dark inside - unlike our current all-porthole boat! The difference is that our current boat has a nice big pidgeon box with four portholes in the roof of the saloon. Makes all the difference!

 

So, how much is it likely to cost to get a steel pidgeon box with four 6" portholes made, fitted and painted should we buy this boat we've seen? And who might do this for us down here on the Thames at Reading?

 

We've also seen what I'd call 'prism lights' in the roof of another boat. Quite effective at illuminating the inside and they look a whole lot easier to fit. A few of these might give just as much light as the pidgeon box. Anyone here have them, or know where they come from?

 

Cheers Mike

Edited November 8, 2008 by mike bryant

[wonderdust]

We have a couple of mason type, they do let quite a lot of light in but ours suffer from condensation now and again, also when we had our bss the examiner checked them as he said there had been recorded accounts ( certain types )of them acting like a magnifying glass and setting fire to boats!

Edited November 8, 2008 by wonderdust

[ditchcrawler]

There's a boat we've seen that we like and it seems probable that we'll buy it. Being all portholes it's a bit dark inside - unlike our current all-porthole boat! The difference is that our current boat has a nice big pidgeon box with four portholes in the roof of the saloon. Makes all the difference!

 

So, how much is it likely to cost to get a steel pidgeon box with four 6" portholes made, fitted and painted should we buy this boat we've seen? And who might do this for us down here on the Thames at Reading?

 

We've also seen what I'd call 'prism lights' in the roof of another boat. Quite effective at illuminating the inside and they look a whole lot easier to fit. A few of these might give just as much light as the pidgeon box. Anyone here have them, or know where they come from?

 

Cheers Mike

Midland Chandlers sell a standard pigeon box for just under £100

http://www.midlandchandlers.co.uk/PIGEON-B...ORTS_A1B5C.aspx

But any good steel worker should be able to make one to your own specification. There was a chap that goes to the boat shows who makes them and side doors that bolt in so you don't need to weld the boat.

[US Marines]

We've got a couple of 'bulls eyes' in the roof - they work very well - adding quite a surprising amount of light for their small size (not that surprising, I suppose, considering how they work ! - doh !) and my experience is that the rectangular prisms work well too. As long as they are seated and sealed properly (and that is important), they shouldn't leak at all.

 

 

We have a couple of mason type, they do let quite a lot of light in but ours suffer from condensation now and again, also when we had our bss the examiner checked them as he said there had been recorded accounts ( certain types )of them acting like a magnifying glass and setting fire to boats!

I'd be EXTREMELY interested to see or hear any proof/first hand accounts of this ever happening. The chances are infinitessimally small in my book - less than your boat catching fire because it is struck by lightning.

 

My guess is that its another Elf & Safety myth - similar to mobile phones at filling stations.....

Edited November 8, 2008 by US Marines

[wonderdust]

Ok!

[US Marines]

Sorry wonderdust - I wasn't aiming that at you - all you are doing is passing on something in good faith that you've been told by a 'professional'.....but I still would be really interested in any proof of this ever happening......

 

 

....if anyone on the forum has experienced anything like this, perhaps they could let us know.....

Edited November 8, 2008 by US Marines

[US Marines]

Post deleted coz it didn't add anything.

Edited November 8, 2008 by US Marines

[alan_fincher]

I'd be EXTREMELY interested to see or hear any proof/first hand accounts of this ever happening. The chances are infinitessimally small in my book - less than your boat catching fire because it is struck by lightning.

 

My guess is that its another Elf & Safety myth - similar to mobile phones at filling stations.....

 

Worth reading this then....

 

(Warning to those on slow connections - it's a PDF document)

 

http://www.boatsafetyscheme.com/downloads/...ght%20FINAL.pdf

 

Looks like several near misses, rather than major conflagrations.

Edited November 8, 2008 by alan_fincher

[US Marines]

Worth reading this then....

 

(Warning to those on slow connections - it's a PDF document)

 

http://www.boatsafetyscheme.com/downloads/...ght%20FINAL.pdf

 

Looks like several near misses, rather than major conflagrations.

Thanks Alan - and I guess its sensible advice....but....

 

many years of use in lots of boats......some evidence of rare scorching events taking place......no mention of whether those particular prisms were cracked or otherwise unusually focusing the rays to the side etc.

 

I can't work out why a properly installed and undamaged lens would cause the roof lining next to it to get so hot as to scorch....seems really strange to me....

 

Yes, you don't want to put anything combustible at its focal length (I'm guessing ours are around 100mm or so) but that's pretty obvious and, in most cases, quite difficult to do (other than perhaps curtains or something in a traditional back cabin)....

 

Not a reason for not installing them, as far as I'm concerned.....

Edited November 8, 2008 by US Marines

[alan_fincher]

Thanks Alan - and I guess its kind of sensible advice....but....

 

......how many boats are there with a table or floor or any other surface where there's the possibility of there being anything combustible at the focal lengths we're talking about here ?

Sort of agree, but the BSS people seem to only issue that kind of ad-hoc bulletin fairly occasionally. I guess they must have had enough 'concern' examples to do so.

 

I didn't quite understand the "charred wood in ceiling" picture, TBH, but it's the kind of thing one can well do without!

[johnthebridge]

We've got a couple of 'bulls eyes' in the roof - they work very well - adding quite a surprising amount of light for their small size (not that surprising, I suppose, considering how they work ! - doh !) and my experience is that the rectangular prisms work well too. As long as they are seated and sealed properly (and that is important), they shouldn't leak at all.

 

 

 

I'd be EXTREMELY interested to see or hear any proof/first hand accounts of this ever happening. The chances are infinitessimally small in my book - less than your boat catching fire because it is struck by lightning.

 

My guess is that its another Elf & Safety myth - similar to mobile phones at filling stations.....

I can tell you that this has happened to me once, and once to a friend. Because I was on it at the time, my boat did not suffer any significant damage, but my friends boat was severely damaged. Both of us were aware of the potential dangers involved, and on leaving our boats, would cover up the bulls-eyes with an inverted dog bowl, but his was lifted off by high wind, which left it unprotected. With a bulls-eye fitted the "wrong way", i.e. with convex side uppermost, it is a very real danger. The danger is exacerbated if the bulls-eye is located near a timber fitting like a roofbeam, as in a back cabin.

[US Marines]

I can tell you that this has happened to me once, and once to a friend. Because I was on it at the time, my boat did not suffer any significant damage, but my friends boat was severely damaged. Both of us were aware of the potential dangers involved, and on leaving our boats, would cover up the bulls-eyes with an inverted dog bowl, but his was lifted off by high wind, which left it unprotected. With a bulls-eye fitted the "wrong way", i.e. with convex side uppermost, it is a very real danger. The danger is exacerbated if the bulls-eye is located near a timber fitting like a roofbeam, as in a back cabin.

 

Couple of things I need to say:

 

(1st) Sorry, I was editing my post above for ages (because the phone rang) after posting it by mistake before I'd finished - and I only then discovered that Alan & you, John had then replied already.

 

(2nd) OK John, now that really does sound like first hand evidence - and I'm VERY sorry to hear of it - can you please explain the details of the event(s) where this did happen to you/your friend a bit more - was it a curtain for example, or the roof lining than initially caught fire ? Thanks.

Edited November 8, 2008 by US Marines

[johnthebridge]

Couple of things I need to say:

 

(1st) Sorry, I was editing my post above for ages (because the phone rang) after posting it by mistake before I'd finished - and I only then discovered that Alan & you, John had then replied already.

 

(2nd) OK John, now that really does sound like first hand evidence - and I'm VERY sorry to hear of it - can you please explain the details of the event(s) where this did happen to you/your friend a bit more - was it a curtain for example, or the roof lining than initially caught fire ? Thanks.

Will do after the Wales-Boks match!

[andywatson]

There's a boat we've seen that we like and it seems probable that we'll buy it. Being all portholes it's a bit dark inside - unlike our current all-porthole boat! The difference is that our current boat has a nice big pidgeon box with four portholes in the roof of the saloon. Makes all the difference!

 

So, how much is it likely to cost to get a steel pidgeon box with four 6" portholes made, fitted and painted should we buy this boat we've seen? And who might do this for us down here on the Thames at Reading?

 

We've also seen what I'd call 'prism lights' in the roof of another boat. Quite effective at illuminating the inside and they look a whole lot easier to fit. A few of these might give just as much light as the pidgeon box. Anyone here have them, or know where they come from?

 

Cheers Mike

 

I made 2 pigeon boxes from inch thick oak at a cost of about £20 the pair

for the wood and about £5 for steel profiles to cover the ridge and slightly overlap the gap where the sloping bit meets the ridge. This is painted black and the oak is dark stained then oiled

Each has 6 small brass portholes (3 each side) lifted from the previous rotting pair.

 

They look nice and don't get condensation which might well affect steel but probably are not so secure.

Worth considering if you like woodwork more than spending money!

[ditchcrawler]

I made 2 pigeon boxes from inch thick oak at a cost of about £20 the pair

for the wood and about £5 for steel profiles to cover the ridge and slightly overlap the gap where the sloping bit meets the ridge. This is painted black and the oak is dark stained then oiled

Each has 6 small brass portholes (3 each side) lifted from the previous rotting pair.

 

They look nice and don't get condensation which might well affect steel but probably are not so secure.

Worth considering if you like woodwork more than spending money!

Are add's allowed as I have 4 small portholes that I took out of mine in the shed.

[MtB]

Are add's allowed as I have 4 small portholes that I took out of mine in the shed.

 

Hi DC

 

Portholes in your shed? Great idea! I bet they look cool!

 

Won't the rain get in though if you take them out and sell them to me ;-)

 

Cheers, Mike

 

P.S. how much do you want for them?

[johnthebridge]

I had a cheap plastic clock stuck on the middle beam in the back cabin of "Amsterdam". On a very hot day on the Severn, with the sun belting through the bulls-eye, this melted and subsequently caught fire, taking the bed-hole curtain and lace with it. It was quite alarming, to say the least, when smoke started billowing up through the slide. The curtain, the lace and the clock were ripped out and chucked in the river. The beam was scorched.

Previously when leaving my boats I'd always put covers over the bulls-eyes, but from that time on, whenever the sun came out with any strength, I'd put the dog bowl on, even when on the boat.

I think that it's probably right to say it's unlikely that a fire is going to start through a bulls-eye where there is no adjoining inflammable material, but I would still cover them if leaving the boat.

My friend's boat was on its mooring. He was at work, but fortunately a neighbour spotted smoke coming from the back cabin slide. The fire investigator was adamant that the fire had started in the area of the beam, next to the bulls-eye........

Subsequently, and on advice, I painted small black circles in the middle of the glasses to "break" the sun's effect, but I remain unconvinced of the efficacy of this.

Edited November 8, 2008 by johnthebridge

[US Marines]

I had a cheap plastic clock stuck on the middle beam in the back cabin of "Amsterdam". On a very hot day on the Severn, with the sun belting through the bulls-eye, this melted and subsequently caught fire, taking the bed-hole curtain and lace with it. It was quite alarming, to say the least, when smoke started billowing up through the slide. The curtain, the lace and the clock were ripped out and chucked in the river. The beam was scorched.

Previously when leaving my boats I'd always put covers over the bulls-eyes, but from that time on, whenever the sun came out with any strength, I'd put the dog bowl on, even when on the boat.

I think that it's probably right to say it's unlikely that a fire is going to start through a bulls-eye where there is no adjoining inflammable material, but I would still cover them if leaving the boat.

My friend's boat was on its mooring. He was at work, but fortunately a neighbour spotted smoke coming from the back cabin slide. The fire investigator was adamant that the fire had started in the area of the beam, next to the bulls-eye........

Subsequently, and on advice, I painted small black circles in the middle of the glasses to "break" the sun's effect, but I remain unconvinced of the efficacy of this.

Thanks John - your experiences have certainly made me think again about all this.....

 

Yeah, I had heard that some people painted black circles on the centre of them, used some translucent film on them or even ground a flat off the top of the 'dome'. Prior to today, I thought all this was nonsense but, obviously, that's not quite the right attititude......

Edited November 8, 2008 by US Marines

[dave moore]

Hi all

The triangular section rectangular prisms available from Midland Chandlers cast an amazing amount of light inside and are not a potential fire hazard at all. Bedded in with silicon they hardly disturb the look of the roof (from the outside) at all. If that sounds confusing, visualise a glass Toblerone bar!

The "Bull eye" glass can indeed be a fire hazard and I had a narrow escape years ago on Resolute...scorch marks on the tube below which could have developed well into a fire...the solution, proposed by another boater at Norton Canes ( a retired scientist and engineer) was to cut a circle of "frosted" acrylic sheet similar to bathroom window glass and attach it with silicon. The theory behind this is that the perspex acts as a diffuser and the bull eye is unable to focus. No problems since!

Cheers

Dave

[johnthebridge]

Hi all

The triangular section rectangular prisms available from Midland Chandlers cast an amazing amount of light inside and are not a potential fire hazard at all. Bedded in with silicon they hardly disturb the look of the roof (from the outside) at all. If that sounds confusing, visualise a glass Toblerone bar!

The "Bull eye" glass can indeed be a fire hazard and I had a narrow escape years ago on Resolute...scorch marks on the tube below which could have developed well into a fire...the solution, proposed by another boater at Norton Canes ( a retired scientist and engineer) was to cut a circle of "frosted" acrylic sheet similar to bathroom window glass and attach it with silicon. The theory behind this is that the perspex acts as a diffuser and the bull eye is unable to focus. No problems since!

Cheers

Dave

Hello Dave,

I think it's only on the canal that bulls-eyes get put in the "wrong" way. Most barges and seaboats of my acquaintance have the flat side uppermost. This obviates the fire hazard, and, I think, creates more light inside, but does allow water to sit on the glass.

John.

[US Marines]

Mike - if you haven't already worked it out - listen to Dave and John (et al) not me !

 

Those glass Toblerones sound the business.....

 

 

 

Having said that - the glass toblerones and a bulls-eye flat side up would just spread out the light that would otherwise have come in through the same size hole in the roof - whereas the bulls eye dome uppermost deflects some of the light that would have passed over the top of the boat, into it......so should lead to a brighter interior for the size of glass....

Edited November 8, 2008 by US Marines

[johnthebridge]

Mike - if you haven't already worked it out - listen to Dave (et al) not me !

 

Those glass Toblerones sound the business.....

Only thing is, they're a bugger if, like me, you're tall. Oww!

[dave moore]

Hi John

According to Colin, my scientist friend, it made no difference whether the glass was installed curved or flat side up...it would still act as a focusing lens. My physics days are well behind me so I can't comment on the accuracy of this statement, but this was a guy who designed satellites in his day job and produced an excellent set of offset controls for his DM2. He was well respected at the yard as a problem solver. Should ther be a "D" in pigeon?

Dave

[ditchcrawler]

Hi John

According to Colin, my scientist friend, it made no difference whether the glass was installed curved or flat side up...it would still act as a focusing lens. My physics days are well behind me so I can't comment on the accuracy of this statement, but this was a guy who designed satellites in his day job and produced an excellent set of offset controls for his DM2. He was well respected at the yard as a problem solver. Should ther be a "D" in pigeon?

Dave

Mine is flat side up and the sun often focuses on the liner which is white, shiny GRP and it hits it at quite an angle, so far this has not caused a problem. As for the D in pigeon, I did hear there is no F in fish due to the storms.

[John Orentas]

Mine is flat side up and the sun often focuses on the liner which is white, shiny GRP and it hits it at quite an angle, so far this has not caused a problem. As for the D in pigeon, I did hear there is no F in fish due to the storms.

 

 

Yes this story about bulls eye lenses is the kind of thing that I my cynical brain would normally discount or at least be very sceptical about but as the few earlier posts would indicate is was quite well authenticated a couple of decades ago.. The problem is that a totally burned out boat will leave no clues as to it's cause..

 

But again as the earlier post indicated there were several near misses reported and if I remember some of the scorching to the boat interiors were to some extent confirmed by some testing of the focal lengths of the prisms.