Old Proctor mast 'rivets'

share hints, tips and experiences
Post Reply
ian60
Posts: 51
Joined: Fri Aug 17, 2012 10:04 am

Old Proctor mast 'rivets'

Post by ian60 »

I am 'renovating' an old Proctor mast (early 60's, with diamonds - pale blue!). There is a separate semi circular cast aluminium fitting where the forestay connects, it partially covers the jib sheave box. It appears to be fitted to the mast with some sort of aluminium 'rivets' 4 in total, each about 5mm dia and about 12mm long with a central core about 1.5mm. Not rivets as I understand them but they have to come out to replace the long dead, tufnol sheave box. Does anyone know anything about these 'rivets'. I have test drilled one of them out. Do such things still exist so that I can replace the fitting in due course or does anyone know of a suitable alternative fastening? I could use some 5mm dia aluminium rod, drill out the centre and then peg/rivet them but I'm not confident of a strong result.
Re the painted finish on the mast - it appears to be original in that in some places the finish has remained remarkably good, is undercoated and continues in all the hidden places that a home respray would have missed. Did Proctors have this finish as an option back in the 60's?. I have an almost identical mast that is just natural aluminium, no coating whatsoever which is in quite good condition and the invoice for that states 'natural' finish which makes me suspect alternatives were available.
User avatar
trebor
Posts: 961
Joined: Mon Jan 02, 2012 1:53 pm
Location: West Midlands

Re: Old Proctor mast 'rivets'

Post by trebor »

Robert
Minisprint 4230
Tinker Traveller 160
Mirror 61147 Anastasia
http://www.aquabatdinghy.co.uk
realnutter
Posts: 212
Joined: Mon Aug 03, 2015 11:18 pm

Re: Old Proctor mast 'rivets'

Post by realnutter »

Except they really ought to be monel...

http://www.ebay.co.uk/itm/Tucker-Monel- ... XQYwFRg59j
Matt

Int Moth K2992
ian60
Posts: 51
Joined: Fri Aug 17, 2012 10:04 am

Re: Old Proctor mast 'rivets'

Post by ian60 »

Thanks for the comments, they are definitely not pop rivets (aluminium core as well as the outer) I'll try to post a picture.
I didn't realise pop rivets went up to such large diameters so may well be a solution.
Michael4
Posts: 504
Joined: Fri Jan 03, 2014 5:25 pm
Location: West Sussex

Re: Old Proctor mast 'rivets'

Post by Michael4 »

I think I know what you mean, are they solid and end up flush with the surface? Countersunk in some way? If so I wouldn't know where to find them. They appear to be similar to the sort of things you'd find on an English Electric Lightening! Good for reducing drag and breaking the sound barrier...unhelpful I know, I ended up using pop rivets, alloy nuts and bolts and to be safe some of that green slime.
Tideway 206
11+
Sold the 'Something bigger and plastic', it never got used.
Chrisrjwood
Posts: 170
Joined: Sun Nov 27, 2011 11:33 pm
Location: Suffolk

Re: Old Proctor mast 'rivets'

Post by Chrisrjwood »

Don't forget... If you are using big aluminium rivets, Monel or stainless steel, you will need a man size riveter, probably the lazy tongs variety, otherwise you won't be able to set the rivets, unless you know two friendly gorillas who can work a pliers type riveter for you :?
Chrisrjwood
Jollyboat J325 Serendipity
Rouse I14 'Brown Trousers' K1094
Kirby 7 I14 Last Chance K1120
Penultimate I14 K1337
Int 14 K391 Velocity
Uffa Fox I14 Nymph K524 (under restoration)
Michael Brigg
Posts: 1663
Joined: Fri Jul 06, 2007 7:11 pm
Location: Gosport, UK

Re: Old Proctor mast 'rivets'

Post by Michael Brigg »

Michael4 wrote:I think I know what you mean, are they solid and end up flush with the surface? Countersunk in some way? If so I wouldn't know where to find them. They appear to be similar to the sort of things you'd find on an English Electric Lightening! Good for reducing drag and breaking the sound barrier...unhelpful I know, I ended up using pop rivets, alloy nuts and bolts and to be safe some of that green slime.

Not green but yellow, Zinc Chromate paste. Stick it in the hole and around the rivet before tightening . Its what the mast makers and riggers use. Easy and inexpensive (especially when compared with the cost of a failed shroud!

Image
Michael Brigg
ian60
Posts: 51
Joined: Fri Aug 17, 2012 10:04 am

Re: Old Proctor mast 'rivets'

Post by ian60 »

Michael, yes the holes on the mast fitting are slightly recessed so the end result is a virtually flush surface. The 'rivet' is not solid as it appears to have a narrow core of the same material (though at a quick glance it appears solid, but when the surface is filed back the core can be seen). it looks like the core may have been inserted - or pulled through - after the outer was put into the hole. It's a bit like the plastic expansion fittings you get on cars where you push in the fitting then tap in a central core which expands the outer locking it into place in the hole.

Chris, many times I've wished I had 'retained' a good old Lazy Tong from my teenage years in an engineering works. All I ended up with was an enormous old aluminium frying pan that could have fried about thirty eggs at a time - never did use it though.

Thanks for your comments everyone.
realnutter
Posts: 212
Joined: Mon Aug 03, 2015 11:18 pm

Re: Old Proctor mast 'rivets'

Post by realnutter »

Early "pop" rivets apparently left none of the mandrel in place after setting, if this article from August 1942 is to be believed...

https://books.google.co.uk/books?id=Xic ... non&f=true

Scroll about halfway down to find the relevant bit....

This would leave a hollow rivet in place, so perhaps a slightly tapered and oversize aluminium core was banged into them to increase strength?
Matt

Int Moth K2992
ian60
Posts: 51
Joined: Fri Aug 17, 2012 10:04 am

Re: Old Proctor mast 'rivets'

Post by ian60 »

Thanks for all the interest - I've definitely escaped many chores whilst following up all the interesting leads. I think we may be on to something with 'drive rivets'

http://www.southco.com/en-gb/10-38

I can't be 100% sure but these are very much like what came out of the mast (because I threw them in the bin and now can't find them!!!!).
Brian E. Evans
Posts: 127
Joined: Sat Oct 02, 2004 6:31 am
Location: USA
Contact:

Re: Old Proctor mast 'rivets'

Post by Brian E. Evans »

You may have a style of rivet known as a " Cherry rivet" these were used in the aircraft industry to overcome the deficiencies of the pop rivet i.e. lack of shear strength. the rivet has a solid mandrel that pulls up through the rivet expanding it ,then shears off at the top of or slightly above the head . they were finished off by snipping the excess stem off then dressing the rivet flat with a file. they can be found in the UK at several distributors here is one of them Wesco UK - Huddersfield
Park Mill Way
Clayton West, Huddersfield
West Yorkshire HD8 9XJS

United Kingdom

Tel: +44 1484 867 701

Fax: +44 1484 867 711

UKSales@wescoair.com

I hope this is of some help the tapit or Southco drive pins do not expand all the way to the top of the hole and you can get movement in the joint after a few months use.
Brian Evans.
ian60
Posts: 51
Joined: Fri Aug 17, 2012 10:04 am

Re: Old Proctor mast 'rivets'

Post by ian60 »

Thanks for the info. I've recently completed that part of the mast. By pure fluke I picked up some large diameter rivets which had been left by a workman beneath a sign he had been installing at a motorway service area. They worked well and I'm hopeful they will last.

Ian
Post Reply