Rega Tone Arm Thread Size

Does anyone actually know the thread dimensions and type of
thread on a Rega TA base - the bit that bolts through the
plinth.

As far as I can work it out it 7/8" 25TPI 55Deg pitch. In
other words a totally unique thread :-(

None of my thread gauges can identify it. Can someone
please give me the actual specs.

Cheers TT

TT wrote:
Does anyone actually know the thread dimensions and type of
thread on a Rega TA base - the bit that bolts through the
plinth.

Having a quick google, I come across the description 32mm A/F [1] and
someone's upgrade story finding that a bicycle spanner fits to tighten
it. Knowing the story of Rega's beginnings could it be possible that you
might find matching components in a cycle shop? [2] :-p BTW I also found
claims that tightening the base nut too much could be detrimental to the
sound...

Probably worth giving Origin (the arm rebuilders) a call - they may tell
you if Rega don't. I've got a P3-24 which one day I'd like to mess about
for changing carts from Rega's (fine) own. I'm just a bit tight paying
for a set of spacers at the moment, £15 each - for things stamped out of
sheet metal ;-)

[1] - as useful to finding thread spec as ...
[2] - crazy project idea, build a Hi-Fi turntable out of bicycle bits?

--
Adrian C

Adrian C wrote:
TT wrote:

Does anyone actually know the thread dimensions and type of thread on
a Rega TA base - the bit that bolts through the plinth.


Having a quick google, I come across the description 32mm A/F [1] and
someone's upgrade story finding that a bicycle spanner fits to tighten
it. Knowing the story of Rega's beginnings could it be possible that you
might find matching components in a cycle shop? [2] :-p BTW I also found
claims that tightening the base nut too much could be detrimental to the
sound...

Probably worth giving Origin (the arm rebuilders) a call - they may tell
you if Rega don't. I've got a P3-24 which one day I'd like to mess about
for changing carts from Rega's (fine) own. I'm just a bit tight paying
for a set of spacers at the moment, £15 each - for things stamped out of
sheet metal ;-)

[1] - as useful to finding thread spec as ...
[2] - crazy project idea, build a Hi-Fi turntable out of bicycle bits?

I know a reasonable amount about bikes, but that thread size doesn't
look familiar.
Something close comes up as a brass pipe thread on

http://www.oldengine.org/members/die...les/brass1.htm

Looks more like a plumbing shop than a bike shop that you'll be going to..
it's a shallow nut so you can be a bit flexible on the pitch, I would
have thought.
Roger Thorpe

"Adrian C" wrote in message
...
TT wrote:
Does anyone actually know the thread dimensions and type of thread on a
Rega TA base - the bit that bolts through the plinth.

Having a quick google, I come across the description 32mm

That is the actual outside nut size. I am referring to the threaded bit
inside.

A/F [1] and someone's upgrade story finding that a bicycle spanner fits to
tighten it. Knowing the story of Rega's beginnings could it be possible
that you might find matching components in a cycle shop? [2] :-p BTW I
also found claims that tightening the base nut too much could be
detrimental to the sound...

Overtightening anything can be detrimental :-(


Probably worth giving Origin (the arm rebuilders) a call - they may tell
you if Rega don't.

That's an idea.

I've got a P3-24 which one day I'd like to mess about
for changing carts from Rega's (fine) own. I'm just a bit tight paying for
a set of spacers at the moment, £15 each - for things stamped out of sheet
metal ;-)

Why no VTA is beyond me :-(

Cheers TT

On Thu, 17 Jul 2008 22:33:04 +0800, "TT"
wrote:


"Adrian C" wrote in message
...
TT wrote:
Does anyone actually know the thread dimensions and type of thread on a
Rega TA base - the bit that bolts through the plinth.

Having a quick google, I come across the description 32mm

That is the actual outside nut size. I am referring to the threaded bit
inside.

A/F [1] and someone's upgrade story finding that a bicycle spanner fits to
tighten it. Knowing the story of Rega's beginnings could it be possible
that you might find matching components in a cycle shop? [2] :-p BTW I
also found claims that tightening the base nut too much could be
detrimental to the sound...

Overtightening anything can be detrimental :-(


Probably worth giving Origin (the arm rebuilders) a call - they may tell
you if Rega don't.

That's an idea.

I've got a P3-24 which one day I'd like to mess about
for changing carts from Rega's (fine) own. I'm just a bit tight paying for
a set of spacers at the moment, £15 each - for things stamped out of sheet
metal ;-)

Why no VTA is beyond me :-(

Well, a few years back, I designed a VTA adjuster for my
Rega with the help of my friend, a skilled machinist. He
could not find a standard tap to match and had to cut the
parts using a custom-fashioned cutter tool and the thread
cutting facilities on his lathe. I will ask him if he still
has the specs.

Kal

"Kalman Rubinson" wrote in message
...
On Thu, 17 Jul 2008 22:33:04 +0800, "TT"
wrote:


"Adrian C" wrote in message
...
TT wrote:
Does anyone actually know the thread dimensions and
type of thread on a
Rega TA base - the bit that bolts through the plinth.

Having a quick google, I come across the description
32mm

That is the actual outside nut size. I am referring to
the threaded bit
inside.

A/F [1] and someone's upgrade story finding that a
bicycle spanner fits to
tighten it. Knowing the story of Rega's beginnings could
it be possible
that you might find matching components in a cycle shop?
[2] :-p BTW I
also found claims that tightening the base nut too much
could be
detrimental to the sound...

Overtightening anything can be detrimental :-(


Probably worth giving Origin (the arm rebuilders) a
call - they may tell
you if Rega don't.

That's an idea.

I've got a P3-24 which one day I'd like to mess about
for changing carts from Rega's (fine) own. I'm just a
bit tight paying for
a set of spacers at the moment, £15 each - for things
stamped out of sheet
metal ;-)

Why no VTA is beyond me :-(

Well, a few years back, I designed a VTA adjuster for my
Rega with the help of my friend, a skilled machinist. He
could not find a standard tap to match and had to cut the
parts using a custom-fashioned cutter tool and the thread
cutting facilities on his lathe. I will ask him if he
still
has the specs.

Kal

That would be greatly appreciated :-)

TIA TT

On Fri, 18 Jul 2008 13:02:19 +0800, "TT"
wrote:


"Kalman Rubinson" wrote in message
.. .

Well, a few years back, I designed a VTA adjuster for my
Rega with the help of my friend, a skilled machinist. He
could not find a standard tap to match and had to cut the
parts using a custom-fashioned cutter tool and the thread
cutting facilities on his lathe. I will ask him if he
still
has the specs.

Kal

That would be greatly appreciated :-)

I emailed him and he says he cannot recall (it was about 6
years ago) and he does not have the info (he moved his shop
about 3 years ago).

Sorry. As I sit here, I am looking at one of the threaded inserts
that he made for me but there's no more info in that than there
is in the arm threads themselves.

Kal

TT wrote:
Why no VTA is beyond me :-(


Adjusting VTA or not is apparently a contentious issue between vinyl
freaks. Couple of articles here.

http://www.n.mackie.btinternet.co.uk/documents/regaonvta.html
http://www.vtaf.com/vtaf_install.html

I've even seen a yank arm mod for adjustable VTA, that has a LED digital
display to show the height adjustment!

Of course, the problem with the Rega line is the limited build height of
their own carts. And why spacers are sometimes necessary to raise the
height of the mounting for compatibility with other manufacturers carts.

http://www.rega.co.uk/index2.htm

"Note: On all Rega turntables spacers should not be necessary.

Arm Height or V.T.A adjustment can be a controversial subject. Rega
believes that the integrity of the arm fixing onto the arm mounting
board is much more important than the questionable facility of arm
adjustment: The arm should be reasonably parallel to the record surface
or slightly lower at the mounting. The only time a spacer is necessary
to raise the arm height is if the rear of a cartridge is hitting the
record whilst playing"

--
Adrian C