[Healeys] hardtop fasteners - the sequel

[Alan Seigrist]

Mirek -

Hey, great news.  Thanks for letting us know!

Alan

'52 A90
'53 BN1
'64 BJ8


On Fri, May 8, 2009 at 10:45 AM, Mirek Sharp <m.g.sharp at sympatico.ca> wrote:

> Hey all,
>
> You may recall a few weeks ago I posted a plea for information on 8-36
> machine
> screws in stainless, Phillips drive, oval head, for attaching the toggle
> clamps on the front corners of factory hardtops.  I have no idea if the
> specification changed over time, but I have a very original hardtop dated
> 1960, and the threads are definitely 8-36.
>
> Many thanks to all who sent leads, but it turns out these seem to be
> unavailable.  I had one offer from a fastener manufacturer in the UK to
> make
> them, but it was a minimum 250 quid, and I figured it may be a while before
> I
> could recoup this, selling 4 screws at a time to those of you out there
> with a
> hardtop restoration in your future.  Peter Svilans and I checked out a few
> examples and it turns out that the toggle clamps are often fastened with
> self-tapping screws.  I am sure this is not right - who would use a
> self-tapping screw to fasten something to a block of aluminum?  My opinion
> is
> that when the original 8-36 machine screws loosened and fell out, or were
> removed and lost, owners also found replacements were unobtainable and used
> the self-tappers.  On my top, one side had machine crews and the other had
> self-tapping screws.
>
> I had given up on the 8-36 screws and was over at Peter's discussing a
> solution.  I figured I would try taking the nearest, larger thread I could
> find, and re-thread them with a die.  Peter and I checked through some
> metric
> sizes and lo and behold discovered that an M4 with a 0.7 pitch is, for all
> intents, an exact match for an 8-36.  Moreover, it is available in Phillips
> drive, oval head and stainless.  So there we have it - I bought 4 and my
> toggle clamps are re-installed - the metric screws went in perfectly.  I am
> sure the thread form is different, but guess what, once installed you can't
> tell - I tried and you really can't see them (and if any concours judge
> reading this ever removes one of these screws with a thread gauge in hand,
> I
> will break his Phillips drive).  I have no idea how common this particular
> metric machine screw is, but Spaenaur carry them and the part number for a
> 16
> mm length is 425-008.
>
> Cheers,
>
> Mirek
> 60 BT7
> _______________________________________________
> Support Team.Net http://www.team.net/donate.html
>
> Healeys at autox.team.net
> http://autox.team.net/mailman/listinfo/healeys
>
> You are subscribed as healey.nut at gmail.com
>
> http://www.team.net/archive