On Mon, 09 Feb 2015 13:48:50 +1100, F Murtz
wrote:

MM wrote:
On Sun, 08 Feb 2015 19:39:51 +0000, newshound
wrote:

On 08/02/2015 16:45, MM wrote:
On Sun, 08 Feb 2015 16:34:00 +0000, Bob Minchin
wrote:

MM wrote:
On Sun, 08 Feb 2015 15:02:52 +0000, newshound
wrote:

On 08/02/2015 14:36, MM wrote:
I have a domestic paper guillotine (BABS Premier 14) that I want to
fix to a wooden shelf. There is a flange each side with a hole on each
corner. Previously, I just used M6 bolts and nuts through the holes
and the shelf, but now I want to hang drawers underneath the shelf and
the bolts/nuts would get in the way.

Hence my idea of using spire nuts like the ones used extensively in
the auto industry. I'd drive Posidrive screws from underneath the
shelf into the spire nuts. If the screw heads were countersunk, they
would not get in the way of the drawers at all.

But thinking back to my days as a motor fitter, these spire nuts were
intended for *body panel* steel, which isn't very thick. The steel
flanges on the guillotine are 2.5mm thick. Is that too thick for a
spire nut?

MM

Surely a countersunk machine screw from underneath, with a nut on the
top is the simplest option. All sizes/types available in relatively
small quantities from eBay.

See my reply to Bob above. The fixing flanges are on the *inside*.

MM

Glue the nuts and a serrated spring washer in place first. this should
be enough to allow assembly and then when tightening, the spring washer
should take over, break the glue and keep it tight.

Yep, that was pretty much my first idea. But I don't have any suitable
glue or (for your suggestion) serrated washers, so it could be cheaper
buying the spire nuts! I'm first going to check my local hardwarew
store tomorrow. Yes, we still have an old-fashioned store with boxes
of loose screws, nuts, etc. They may well stock spire nuts, too, as
they have pretty much every other kind of fixing.

Since I wrote this I had another brainwave: Stick the nuts in place
with Bluetak! I do have plenty of that. Then gingerly insert each
screw.

MM

Or tap the flange.

Good idea, but the manufacturer decided elongated holes would be best,
for some reason. the holes are MUCH larger than even M8 bolts.
'Course, I could just drill four new holes...! (But would 2.5mm metal
thickness be sufficient to take a thread that would endure?)

MM


Google rivnuts.

Man! Boy oh boy! Now THAT is an excellent idea! I didn't just Google,
I went on to Amazon and found several inexpensive rivnut setting tools
(although the cheapest (from Silverline) got very poor reviews).

Brilliant. Brilliant Brilliant. Thanks! Never heard of these things
before, and I can now see other uses for them round the house and in
general DIY.

MM