Dealing with boatyard/contractors

[alan_fincher]

I've been on the phone to the steel merchants I used to work for to get a quote for myself. The steel comes in 6'x3' plates. It's a big warehouse and I've never seen coils of metal of that thickness. Thin stuff for pressing and moulding, yeah, but not plate.

 

I'm no expert, but if you are talking about a full over-plate of your boat, (are you?), then using sheets that small sounds wrong to me.

 

Sounds like an awful lot of joins that could be avoided by using bigger sheets.

 

Aren't most narrow-boats more than 6' across the baseplate? (Unless we are talking a V bottom, such as a Springer?).

[TheWilk]

6'10" wide, I assumed they'd be doing it in some sort of patchwork style...

 

I really don't know what to think any more, I feel like I'm in way over my head and can't trust any one.

 

You read the horror story building blogs and hope it will never happen to you, don't you?

[alan_fincher]

6'10" wide, I assumed they'd be doing it in some sort of patchwork style...

 

Unlikely to be that across the baseplate though.

 

I think a lot of boats are built using 2 metre wide plates for the base, so about 6 foot 7 iches (-ish).

[TheWilk]

Unlikely to be that across the baseplate though.

 

I think a lot of boats are built using 2 metre wide plates for the base, so about 6 foot 7 iches (-ish).

 

Of course, it's widest around the gunwales. I'm not thinking straight.

[Alastair]

 

 

Sounds like an awful lot of joins that could be avoided by using bigger sheets.

 

You need the joins, for strength.

 

Imagine if they could buy a plate the full size of the baseplate. It would only be joined at the edges. Not a lot of strength there.

 

Also, the plates have to be manageable.

 

In fact it is normal practice to drill holes in each added plate, weld the plate to the baseplate at the hole, then fill the hole back with weld.

 

There is a reason why overplating is expensive.

[alan_fincher]

You need the joins, for strength.

 

Imagine if they could buy a plate the full size of the baseplate. It would only be joined at the edges. Not a lot of strength there.

 

Also, the plates have to be manageable.

 

In fact it is normal practice to drill holes in each added plate, weld the plate to the baseplate at the hole, then fill the hole back with weld.

 

There is a reason why overplating is expensive.

 

Yes, I know all that.

 

But would you expect an over-plated base to have a join the whole way down the middle?

 

I thought, (but maybe wrong!), that you would at least use full width steel, acknowledging what you have said about supporting those plates other than at the edges.

 

I would have thought 6' x 3' plates were a very unlikely size to use - being not big enough to go across the base in their longer direction, or indeed in the other direction, if you join two plates.

 

Happy to be educated about what plate size is used for a typical boat with a base of (say) 2 metres width, though.

[TheWilk]

Well if you look at my baseplate it's not uniformly flat so I think smaller plates is a better idea.

[bargemast]

I've just looked back at their original quote:

 

 

Supply 8 no sheets of 6mm marine grade steel 9 sheets £96.00 £912.00

 

Anyone spot the mistake(s)?

 

I've been on the phone to the steel merchants I used to work for to get a quote for myself. The steel comes in 6'x3' plates. It's a big warehouse and I've never seen coils of metal of that thickness. Thin stuff for pressing and moulding, yeah, but not plate.

 

Working at a steel merchant won't show you how steel arrives at the bigger steel suppliers places in coils, there it's decoiled and delivered in the required lenghts to the ordinary steel merchants.

 

I've transported big coils weighting between 22 and 30 Tons up to 2.5m wide, these are regulairy transported by water.

 

I'll add a few lines of a Dutch steel supplier where you can get decoiled hot rolled steel of maximum 20mm thick/ 2.5m wide, and up to 16m lenght made into flat plate.

 

qualities:

Corten A & B / S355J0WP / S355J2WP / S355J0W / S355J2W

according to EN 10025-5

widths:

1000 mm up to 2500 mm natural rolling sides

(see diagram below)

thicknesses:

0.60 up to 1.50 (cold rolled) and 2.0 up to 20 mm (hot rolled)

lengths:

less than 800 mm and up to 16000 mm

quantities:

from one plate

certificate:

3.1 according to EN 10204

delivery:

ex works or free destination (BeNeLux and Germany)

Delivery time:

Standard 1.5 - 2 weeks after order. Incidentally, a faster delivery time in consultation.

stock:

Novio Steel in the Netherlands has a large wide graded stock sheets in standard sizes to choose from. Delivered within 1-2 working days

 

Hope this helps in making you believe,

 

Peter.

Edited October 11, 2013 by bargemast

[Alastair]

 

Yes, I know all that.

 

But would you expect an over-plated base to have a join the whole way down the middle?

 

I thought, (but maybe wrong!), that you would at least use full width steel, acknowledging what you have said about supporting those plates other than at the edges.

 

I would have thought 6' x 3' plates were a very unlikely size to use - being not big enough to go across the base in their longer direction, or indeed in the other direction, if you join two plates.

 

Happy to be educated about what plate size is used for a typical boat with a base of (say) 2 metres width, though.

I think you are making the assumption that weld is weaker than steel. That isn't the case (as long as the welder is competent).

[alan_fincher]

I think you are making the assumption that weld is weaker than steel. That isn't the case (as long as the welder is competent).

No I wasn't.

 

I was assuming that if you could buy sheets actually about the correct size with little wastage, and avoid the need for, and labour involved in, lots of additional welding, that that would be sensible.

 

Surely there is an actual and maybe not insignificant cost in labour and materials for each weld you need to make?

[Alastair]

Possibly it would be easier if you could get plates of the right size. If they are *exactly* right. Chances are, that wouldn't happen. So you'd always end up with a bit of patching.

[TheWilk]

 

Working at a steel merchant won't show you how steel arrives at the bigger steel suppliers places in coils, there it's decoiled and delivered in the required lenghts to the ordinary steel merchants.

 

I've transported big coils weighting between 22 and 30 Tons up to 2.5m wide, these are regulairy transported by water.

 

I'll add a few lines of a Dutch steel supplier where you can get decoiled hot rolled steel of maximum 20mm thick/ 2.5m wide, and up to 16m lenght made into flat plate.

 

qualities:

Corten A & B / S355J0WP / S355J2WP / S355J0W / S355J2W

according to EN 10025-5

widths:

1000 mm up to 2500 mm natural rolling sides

(see diagram below)

thicknesses:

0.60 up to 1.50 (cold rolled) and 2.0 up to 20 mm (hot rolled)

lengths:

less than 800 mm and up to 16000 mm

quantities:

from one plate

certificate:

3.1 according to EN 10204

delivery:

ex works or free destination (BeNeLux and Germany)

Delivery time:

Standard 1.5 - 2 weeks after order. Incidentally, a faster delivery time in consultation.

stock:

Novio Steel in the Netherlands has a large wide graded stock sheets in standard sizes to choose from. Delivered within 1-2 working days

 

Hope this helps in making you believe,

 

Peter.

 

Thanks for that! However, their quote said they were getting 8 or 9 plates (neither of which, at £92 a sheet, add up to £912 - no one spot that?!). There are countless suppliers in the area that could supply those in a matter of days. If they're trying to save me money buying direct from a mill or something, great, but the previous lack of communication and ability to stick to timeframes isn't instilling me with much confidence.

[Machpoint005]

 

Working at a steel merchant won't show you how steel arrives at the bigger steel suppliers places in coils, there it's decoiled and delivered in the required lenghts to the ordinary steel merchants.

 

I've transported big coils weighting between 22 and 30 Tons up to 2.5m wide, these are regulairy transported by water.

 

I'll add a few lines of a Dutch steel supplier where you can get decoiled hot rolled steel of maximum 20mm thick/ 2.5m wide, and up to 16m lenght made into flat plate.

 

qualities:

Corten A & B / S355J0WP / S355J2WP / S355J0W / S355J2W

according to EN 10025-5

widths:

1000 mm up to 2500 mm natural rolling sides

(see diagram below)

thicknesses:

0.60 up to 1.50 (cold rolled) and 2.0 up to 20 mm (hot rolled)

lengths:

less than 800 mm and up to 16000 mm

quantities:

from one plate

certificate:

3.1 according to EN 10204

delivery:

ex works or free destination (BeNeLux and Germany)

Delivery time:

Standard 1.5 - 2 weeks after order. Incidentally, a faster delivery time in consultation.

stock:

Novio Steel in the Netherlands has a large wide graded stock sheets in standard sizes to choose from. Delivered within 1-2 working days

 

Hope this helps in making you believe,

 

Peter.

 

I stand corrected, but I wouldn't expect a canal boatyard to buy from coil in the Netherlands -- surely they'll just buy stock plate from their friendly local stockholder? In any event, it's neither here nor there to the customer who wants his boat overplated -- the yard should just be quoting for the materials they need (and getting their sums right!). Are they charging for the iron ore that goes into the steelworks too?

[David Mack]

The steel comes in 6'x3' plates.

Are you sure? Its normally sold in metric sizes, so I would expect 2 metre x 1 metre.

 

Most modern nbs are built on a 2m wide bottom plate, so with 2m x 1m sheets laid transversely you could at least avoid a longitudinal joint down the middle.

I've just looked back at their original quote:

 

Supply 8 no sheets of 6mm marine grade steel

What is "marine grade steel?? I would expect to see them specifying mild steel Grade 43A to British Standard 4360.

[TheWilk]

Are you sure? Its normally sold in metric sizes, so I would expect 2 metre x 1 metre.

 

Most modern nbs are built on a 2m wide bottom plate, so with 2m x 1m sheets laid transversely you could at least avoid a longitudinal joint down the middle.

 

What is "marine grade steel?? I would expect to see them specifying mild steel Grade 43A to British Standard 4360.

 

The guy I spoke to at the steel merchants gave the measurements in imperial, and I questioned that too. I'm also questioning the price he quoted (over £300 a sheet) because poking around on the internet tells me they should be in the £100 region.

 

Mild steel? I was expecting 316, is that the same thing?

 

I've got a feeling what they mean is "the plates are on back order" and the story they've given me is the equivalent of telling me there aren't any cakes because the chickens haven't laid any eggs yet.

[David Mack]

316 is stainless steel, so I doubt you want that!

[alan_fincher]

A random Google, and looking at the first 5 sites it brought up showed steel plate all being sold in metric sizing.

 

It seems strange you have found someone selling in imperial?

[TheWilk]

316 is stainless steel, so I doubt you want that!

 

well oops... that's what I asked for!

 

eta: ah well, at least it's not as embarrassing as getting my sums wrong. Also explains why the person on the phone quoted me over £300.

Edited October 11, 2013 by TheWilk

[Tuscan]

I would want to be talking to and working with the yard to ensure that they do a good job. Poking fun and picking fault when you don't know if they read this forum is a dangerous strategy in my view.

[bargemast]

 

I stand corrected, but I wouldn't expect a canal boatyard to buy from coil in the Netherlands -- surely they'll just buy stock plate from their friendly local stockholder? In any event, it's neither here nor there to the customer who wants his boat overplated -- the yard should just be quoting for the materials they need (and getting their sums right!). Are they charging for the iron ore that goes into the steelworks too?

 

 

I hope you weren't thinking that I'm trying to sell Dutch steel, it was only ment to show TheWilk that flat steel plates comes of coils, and that these coils existed as thick as 20mm.

 

It's pretty sure that they do it exactly the same way in the UK, it arrives in coils from the steelfactory, after that it will go to a big steel place where they uncoil and cut the coils into sheets of easier and more standard sizes to be sold by their friendly local stockholder, but special sizes can be ordered like 2.5m wide and up to 16m lenght if needed, which would make ripplefree sides much easier to make (of course in that case not in 20mm).

 

Peter.

[Batavia]

What is "marine grade steel?? I would expect to see them specifying mild steel Grade 43A to British Standard 4360.

Just to add a note of pedantry (or clarification)....

 

BS 4360 was superseded by EN 10025 and the "replacement" grade for 43A is normally taken to be EN 10025 S275JR, given the requirement in some European standards for a minimum impact performance.

 

I feel that much of this thread demonstrates the importance of obtaining advice from a surveyor who the OP is able to trust.

 

Chris G