Materials scientist needed...

Sea-Fever

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My saloon cabin windows have started leaking. I took one apart. I'm not sure if it is original Westerly but it looks quite old. I see replacements are pretty pricey.

The frame containing the glass sits on the outside of the boat and is clamped to the GRP by 'interscrews' which pass inside.

Many of these were corroded and just fell apart - hence did not clamp the portlight to the GRP and therefore leaked. They seem to be very puny little things about M3.5 Replacement interscrews can be purchased from Trafalgar but I need 80 in total = £50

A stronger option may be to fit M4 button headed bolts in A4 S/S through to Nylock nuts on the other side. I could put a nylon washer on the outside between button head and the portlight frame....this would seal the screw hole and provide some electrical insulation.

I don't know what the frame is made of I can only say it seems to be original but they are in generally good nick.

Can anyone foresee any problems - galvanic corrosion?? Even with the nylon washers?

Anyone guess what the metal used to make the original portlight frame is?

Thanks for any thoughts.
 

VicS

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My saloon cabin windows have started leaking. I took one apart. I'm not sure if it is original Westerly but it looks quite old. I see replacements are pretty pricey.

The frame containing the glass sits on the outside of the boat and is clamped to the GRP by 'interscrews' which pass inside.

Many of these were corroded and just fell apart - hence did not clamp the portlight to the GRP and therefore leaked. They seem to be very puny little things about M3.5 Replacement interscrews can be purchased from Trafalgar but I need 80 in total = £50

A stronger option may be to fit M4 button headed bolts in A4 S/S through to Nylock nuts on the other side. I could put a nylon washer on the outside between button head and the portlight frame....this would seal the screw hole and provide some electrical insulation.

I don't know what the frame is made of I can only say it seems to be original but they are in generally good nick.

Can anyone foresee any problems - galvanic corrosion?? Even with the nylon washers?

Anyone guess what the metal used to make the original portlight frame is?


Thanks for any thoughts.

Those M3.5 interscrews were a "feature" of older Westerlys Dunno what they were made of but they did tend to corrode. Trafalgar is the only place I know of to buy them and they are very expensive.

Would it be possible to drill the frames, the GRP and the inner bezel to take a larger more readily available size. M4, and larger, in 316 stainless are avaialble from Seascrew . You can use 304 screws on the inside if you wish
 

Sea-Fever

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Those M3.5 interscrews were a "feature" of older Westerlys Dunno what they were made of but they did tend to corrode. Trafalgar is the only place I know of to buy them and they are very expensive.

Would it be possible to drill the frames, the GRP and the inner bezel to take a larger more readily available size. M4, and larger, in 316 stainless are avaialble from Seascrew . You can use 304 screws on the inside if you wish

Thanks for the reply. I actually fitted M4 screws from screwfix as a stop gap until I get some proper jobs and it didn't require drilling.... I bedded the window back in with sealant so changing over the screws in due course one by one won't be a drama.....I won't keep the zinc coated screwfix ones as they will no doubt corrode quickly.
 

Boathook

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Thanks for the reply. I actually fitted M4 screws from screwfix as a stop gap until I get some proper jobs and it didn't require drilling.... I bedded the window back in with sealant so changing over the screws in due course one by one won't be a drama.....I won't keep the zinc coated screwfix ones as they will no doubt corrode quickly.

Try Seascrew. https://www.seascrew.com/browse.cfm...-WINDSCREENS--PORTHOLES--WINDOWS&l=0000000586 . M4 A2 stainless, etc. I have found the company very good over the years.
 

maxi77

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My saloon cabin windows have started leaking. I took one apart. I'm not sure if it is original Westerly but it looks quite old. I see replacements are pretty pricey.

The frame containing the glass sits on the outside of the boat and is clamped to the GRP by 'interscrews' which pass inside.

Many of these were corroded and just fell apart - hence did not clamp the portlight to the GRP and therefore leaked. They seem to be very puny little things about M3.5 Replacement interscrews can be purchased from Trafalgar but I need 80 in total = £50

A stronger option may be to fit M4 button headed bolts in A4 S/S through to Nylock nuts on the other side. I could put a nylon washer on the outside between button head and the portlight frame....this would seal the screw hole and provide some electrical insulation.

I don't know what the frame is made of I can only say it seems to be original but they are in generally good nick.

Can anyone foresee any problems - galvanic corrosion?? Even with the nylon washers?

Anyone guess what the metal used to make the original portlight frame is?

Thanks for any thoughts.

A quick google gives quite a few suppliers including my 'go to' for fasteners Seascrew who seem to charge a bit less at £25 for 50
 

cpedw

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My experience of Westerly window frames is that they are aluminium so I would recommend Duralac to prevent SS/Al corrosion.

Another less messy alternative to Duralac was recommended here recently but I can't remember its name.

Derek
 

VicS

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My experience of Westerly window frames is that they are aluminium so I would recommend Duralac to prevent SS/Al corrosion.

Another less messy alternative to Duralac was recommended here recently but I can't remember its name.

Derek

Tef-Gel
PTFE based and chromate free

There is also Duralac Green. Chromate free but may be just as messy as ordinary barium chromate based Duralac, only green instead of yellow
 

Sea-Fever

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Thanks all for your input. Seascrew certainly have a good range albeit in metric sizes, I've never used duralac or similar products, I may investigate those. If indeed the frames are aluminium then I would look to insulate as much as possible. I see on closer inspection the portlight frames are prone to leaking at the leading and trailing edges....I suspect this is because the frames are manufactured straight but the coachroof sides are slightly curved (convex) if viewed from above. I don't believe the OEM interscrews are man enough for the job as you have to tighten them (probably) beyond their design torque to pull the frame in.

Obviously I know much more about good boat building than Westerly ;-)
 
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