Pencarrow: nothing to see, move along please.

[2ManySpams]

Asbestos sheets can be a bigger pitchthan the steel I think. 1.4mm sounds on the small side to me usual pitch for steel sheet is 3inch or 1.75mm in 7mil. That does suggest to me the sheets are bigger than 6x2 (assuming you have estimated from the sheet width. More likely I think would be 6x 3 sheets with an overall so about 2ft 9in wide visible.

The ones we used for a garage at my old place were 3in pitch and 3 x 6.3 metres (i.e the length of the garage) We needed four sheets to cover the ten foot width due to the overlap and avoided cutting by increasing the overlap.

Don

 

edit P.S. If you want to use them full size go for the ones sprayed with flock underneath stops the condensation drips. Alrigh not needed for the model but it might help someone.

 

Don

 

Morning Don,

 

I settled on a figure of about 2'as the visible width based upon seeing how many of the 18" long concrete blocks it took to run under 10 of the roofing sheets. The answer came out at a smidge over 14 based on a higher resolution photo than I'm posting in the thread.

 

If the visible width of the sheet is closer to 2'9" then that would make the blocks a bit over 2'long and 1' tall. This would make the building much bigger, an extra 3'tall at gutter level and an extra 5'3" by the time ridge level is reached.

 

Assuming that the blocks are 18"x9" works for other dimensions such as door opening heights so I'm fairly sure that the block size is OK. I agree that in many cases the visible width of the roofing sheets is greater than 2'but in this case I think the narrower width is about right.

 

I've also managed to count the blocks in the gable end of the building and this gives the length of the sloping roof at the gable to be a bit over 12', hence why I think the visible portion of the sheet length is about 6'.

 

Not completely scientific but method in my madness.

[2ManySpams]

Dimensions of prototype asbestos sheets here if it helps:http://www.asbestosremovalguide.com/1129/standard-corrugated-asbestos-sheeting/

Dave

Also found this:

 

[2ManySpams]

Shocking news from London but the best thing to do IMO is carry on with life as normal. So, with the sun shining on Pencarrow, here's a few photos of the concrete block building in place on the layout. The walls are still only a single sheet of 1mm plasticard and will be beefed up in my usual manner. The black roof structure is all 1.5mm 60thou and forms the rigid backbone of the building.

 

 

The cardboard box in the yard next to the new building is the rough position of a second building in what I've decided will be a stonemasons yard.

 

 

I quite like the two different aged buildings being next to each other. Something you see every day in the real world.

 

 

Signal box and cottages form the backdrop.

 

 

 

 

Not much to see from Mark's favourite spotting position.

 

 

Right, time to go out into the garden.

[2ManySpams]

As a final thought before going to play with the worms.... The 4mm Wills sheets scale 2'2" wide in 7mm, bang on the width in my diagram above. Far to big for 4mm?

 

[DonB]

Assuming that's a 4mm/ft scale rule, the spacing of the corrugations seems pretty close to me at 7 in 2ft =.£.48"   Don't have a prototype sample to hand, (asbestos is a dirty word in the building trade these days,)  but my failing memory says 3.5" spacing ,Ridge to Ridge is / was the norm.

Edited June 4, 2017 by DonB

[2ManySpams]

That's a 7mm scale rule Don.

[Donw]

Morning Don,

 

I settled on a figure of about 2'as the visible width based upon seeing how many of the 18" long concrete blocks it took to run under 10 of the roofing sheets. The answer came out at a smidge over 14 based on a higher resolution photo than I'm posting in the thread.

 

If the visible width of the sheet is closer to 2'9" then that would make the blocks a bit over 2'long and 1' tall. This would make the building much bigger, an extra 3'tall at gutter level and an extra 5'3" by the time ridge level is reached.

 

Assuming that the blocks are 18"x9" works for other dimensions such as door opening heights so I'm fairly sure that the block size is OK. I agree that in many cases the visible width of the roofing sheets is greater than 2'but in this case I think the narrower width is about right.

 

I've also managed to count the blocks in the gable end of the building and this gives the length of the sloping roof at the gable to be a bit over 12', hence why I think the visible portion of the sheet length is about 6'.

 

Not completely scientific but method in my madness.

 

You are probably right. I had a quick google 660mm corrugated steel sheets are available giving a 2ft sheet spacing and the profile 8 rolls at 3ins the length is 6ft. (Mine were cut to length as they come of the rolling mill). It was the spacing of the rolls that made me think perhaps the sheet was wider. Rolls of under 3ins were unusual until the mini profile plastic sheets were introduced. I would check the spacing of the rolls 

Don

[2ManySpams]

On and off I've spent about 5hrs on the the concrete block building today. What a massive difference...

 

 

Oh.

[N15class]

I hope you are using a decent DPM on the end walls against the railway. Don't want all your hard work suffering with damp problems.

[2ManySpams]

So the almost invisible work has included:

 

Finishing off the 4 main corners to file them flush and carry the mortar lines round.

Thickening the walls up from a single layer of 40thou to 3 layers, including recesses around the window openings to give a bed for the glazing panels.

Some internal bracing.

And adding mortar lines around the window openings.

 

That's it really.

[2ManySpams]

I hope you are using a decent DPM on the end walls against the railway. Don't want all your hard work suffering with damp problems.

It will be to the usual standard of the period Pete, so damp walls it is then ;-p

[bgman]

It will be to the usual standard of the period Pete, so damp walls it is then ;-p

Well, as a retired ( YEY ) Building Inspector you have my FULL permission! )

 

D.Ontcare

[2ManySpams]

Last night I was mostly filing. I decided to use the Wills asbestos sheets and so set about thinning down the visible edges. Left is how the sheet comes and right how it looks once the weight of material has been removed. Firststep is taking a nasty big flat file and chamfering the edge to about 45deg. Then a small round file to form the curvy wavy profile in the underside. Takes a while to do:

 

 

Sheets going on. The white bits of plastic a tabs to give the next sheet more to fix to.

 

 

Another view of the edge.

 

 

Not much to show for 2hrs work...

 

[Simond]

Might take a while to do, but the difference is worth every second....

[Siberian Snooper]

It's doing that little bit extra that lifts a model from being run of the mill to outstanding.

[Stubby47]

One question - the walls only look to be one block thick (pic #3, post 5053). If so, would the set of blocks between the windows not be just 3 rows of single blocks, rather than having one row of two split ones ?

[2ManySpams]

One question - the walls only look to be one block thick (pic #3, post 5053). If so, would the set of blocks between the windows not be just 3 rows of single blocks, rather than having one row of two split ones ?

Walls will be thicker Stu but the glazing units will be added next and then some more wall thickness afterwards. This prevents a gap around the window from and makes sure the glazing units are well fixed.

[Simond]

Stu

 

I suspect you're right

 

Chris

 

I suspect you've answered a different question

 

best

Simon

[2ManySpams]

Stu

 

I suspect you're right

 

Chris

 

I suspect you've answered a different question

 

best

Simon

I would imagine that the building would be single block thickness generally but double block nibs in places in the inside to strengthen the walls. The side with the doors and large openings already has a few nibs included, I'll think about how best to show this on the small window side but a nib between the windows would be a good location IMO.

[Simond]

Not familiar with the word "nib" in this sense, presume it's a pillar inside the wall to double it locally. I'd guess that up the inside of a narrow pillar between two windows would be a sensible place to put it, but wouldn't a doubler make a different pattern of blocks on the outside, if it were bonded in? Alternatively, could it not be simply be tied in with those figure-8 wire thingies in the mortar?

 

Would such a pillar have anything to do with the support for the roof trusses in a building like this? I've been in such buildings, but obviously wasn't paying enough attention...

 

Best

Simon

[2ManySpams]

Not familiar with the word "nib" in this sense, presume it's a pillar inside the wall to double it locally. I'd guess that up the inside of a narrow pillar between two windows would be a sensible place to put it, but wouldn't a doubler make a different pattern of blocks on the outside, if it were bonded in? Alternatively, could it not be simply be tied in with those figure-8 wire thingies in the mortar?

Would such a pillar have anything to do with the support for the roof trusses in a building like this? I've been in such buildings, but obviously wasn't paying enough attention...

Best

Simon

Yes nib would be a local doubling of the blocks. Interestingly the photo I have of the side of the building with the two small windows appears to show a couple of half blocks on the middle pier. For a wall of that length there must have been either internal block partitions, or a double skin or nibs. Not having any of these would result in a long slender wall prone to collapse if a sideways force (wind, roof loading, internal fittings, impact) acted on it.

 

No idea when wall ties came into use. They are common now but in the 50s?

 

I suspect on a building like this the roof trusses could be lightweight angle iron affairs which rest on the wall tops. But that's just guesswork as the building isn't there to look at anymore.

[2ManySpams]

Lots of useful general building info in this website:

 

https://fet.uwe.ac.uk/conweb/house_ages/elements/print.htm

[wagonbasher]

I hope you are using a decent DPM on the end walls against the railway. Don't want all your hard work suffering with damp problems.

 

In those days a vertical DPM would be in the form of a latex and bitumen emulsion.  (Rubberised Bituminous waterproofer).

 

Painted on the outside of the block work two generous coats in opposite directions.

 

Andy

[2ManySpams]

I think wall ties came in with cavity walls and for the concrete block building, physical bonding between block courses is more likely to get used?

[MikeHemmings]

Caverty walls were being used in the construction we'll be for the 1950s.

 

Mike