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Describe thumb nut size and thread on speedo stud

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2wrench

2wrench

Luke Skywalker
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Rebuilding my dash. Got everthing I need except
did not receive (must have been overlooked by shipping)
the knurled nuts that hold the speedometer and the
tachometer onto the wood dash fascia.

These are the little donut looking things with a hole in
the middle that is threaded that screws onto the threaded
stud on the backs of the speedometer and tachometer to hold
them in place.

Special ordered some parts and thought I asked for them too;
maybe they just don't have them.

Anyway, anybody know if they are metric; standard thread;
what size, etc?

Seems like a piece of hardware I can obtain if I knew the
specs. Other of my resources of info are not presently
available. My CD/shop manual is stuck in a computer drive
that died. Got to send to the shop to get it out and repaired.

2wrench
 
Guess I went too far and asked too much this time.
Oh, well, what it is, is that you guys cease to
amaze me. It blows my mind the info you guys come up
with.

Oh, well, I'll get her figured out, and when I do, maybe
I can share the info or something, okay?

Best to a bunch of the best,

2wrench
 
2wrench:
Are they the same size as the Knurled nuts on the guages?
If so, P.M. me with your address I have some extra but they are for the guages.
Be glad to send em to ya.
Kerry
 
Go to Lowes. They have brass ones that are bigger and are a heck of a lot easier to get your fingers on.
 
Re: Describe thumb nut size and thread on speedo s

I tried to measure the studs on the back of a spare speedo and I can tell you they are not standard threads. At first they appeared to be 8-32 but it is not, a standard 8-32 nut would not go on. I then tried to check it with a thread pitch gauge and noting matched up either standard or metric. The studs on the gauges must be 55 deg Whitworth thread.
Sorry, you wont find them at the local hardware store.
/bcforum/images/%%GRAEMLIN_URL%%/frown.gif
 
Re: Describe thumb nut size and thread on speedo s

I have the brass ones on all my gauges, I think that makes, 9 of them total. actually have a couple left.
 
Ahhh, Mannn, that is so cool, except I do need the
knurled nuts that go onto either the tachometer or
the speedometer. Those two instruments have the same
size threaded stud. So I have to pass on yer offer
and thank you very much. Hope to be able to return a
similar gesture some day.

2wrench
 
Thanks, DNK. Yeah, I'll go to Lowe's. Thought
about trying brass and looking about the hardware
store more myself. Thought occurred to me as to
whether or not I could be setting up some kind of
problem putting brass on, electroysis or some such thing.

Hey, if brass has worked for you in the past, I'm
there.

I ordered some rubber O-rings from an outfit that I
can't remember the name of at the moment. Asked if they
could send these nuts. Thought I got a positive, but
then, maybe not. I'll get their name and if they have
more OEM looking stuff, I'll post the info.

Thanks again,

2wrench
 
Re: Describe thumb nut size and thread on speedo s

Yeah, kinda my thoughts as well, but I'll continue
to look. Hate like the dickens to be carrying my
tach or speedo around just when it's ready to go back
in... don't want to drop that sucker or something like
that. My parts look so good. Scattered about the
livingroom and everywhere. My wife is great! She puts
up with it with a good attitude.

Thanks,

2wrench
 
Re: Describe thumb nut size and thread on speedo s

Also, guess it seems I need to put your stuff in
quotes when responding for this thing to make more
sense. I'm-a still learning

2wrench
 
Re: Describe thumb nut size and thread on speedo s

Instead of starting a new post box,just edit your last post to add more.
Here is the ones I use

Gaugeknurlednuts.jpg
 
Re: Describe thumb nut size and thread on speedo s

I think they are BA threads. You could call MoMa Speedometer Repair (New Mexico) or Nisonger Speedometer Repair (Palo Alto, CA) and see if they have replacements in stock.

A quick google search will give you the phone numbers.

Cheers,
John
 
Re: Describe thumb nut size and thread on speedo s

Went to Lowe's. Closest match was a metric,
a :4M .70. Had a really strange experience. Picked
up 4M .70 bolts and removed one of the knurled nuts off
the back of my speedometer. The nut off my speedometer
screwed well right onto the 4M .70 bolt. So I figured
I had it figured. Purchased wing nuts size 4M .70 and then
tried to screw onto the stud on the back of the speedo.
Guess what? It didn't screw on. It feels like if you were
screwing on a lock nut. It stops and I don't feel comfortable forcing it. I purchased again wing nuts
size 4M .70 from another hardware store. Again, it did
not want to go onto the speedometer, but it went onto any
other bolt or threaded stud I tried -- and the nuts right off the speedo also screwed well onto any other bolt or
stud in the store 4M .70.

I will follow up suggestions to contact New Mexico or
Palo Alto (a fairly close neighboring city, I might add) to
inquire.

2wrench
 
Re: Describe thumb nut size and thread on speedo s

Got parts coming from Moma in
Alq., New Mexico. Thanks for the help and the leads.

2wrench
 
Re: Describe thumb nut size and thread on speedo s

Do your self a favor. Before you install the new ones chase the threads with a die.
 
Re: Describe thumb nut size and thread on speedo s

A 2BA thread is 31.4 threads per inch. Not many folks have this die. Some fuel pumps & carbs may also have BA threads. A 32 tpi thread will definitely bind if more than a couple of threads are engaged.
D
 
Re: Describe thumb nut size and thread on speedo s

My only regret is that I have not one iota of
useful information to leave behind on this thread
other than the studs on the back of the gauges of
my TR6 are British made and you ain't gonna find 'em
in the Five and Dime store.

Now that's real value!

Got em coming and I'll take that.

Thanks.

2wrench
 
Re: Describe thumb nut size and thread on speedo s

Moot point now, You can spin an 8-32 die on those threads and change them to accept an easier finding nut.
 
Re: Describe thumb nut size and thread on speedo s

Actually, not so moot. Thought about doing this but
wasn't so sure which thread would be best, etc.

It's killing me waiting for two darned nuts.

I'll tuck this info away and look for it as the
solution should this issue be readdressed.


2wrench
 
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