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Thread size for speedometer stud?

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I

ichthos

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One of the studs is broken off on the back of my bugeye speedometer. It looked like it was around an 8-32, so I planned on welding a screw in. I wanted the threads to match the existing stud. I went to to the hardware and found it is definitely not 8-32. Anyone know what the thread size is and where I can get another?
Kevin
 
The thread size is a subject of arguments. Gauge threads did change over decades.

The original thread on your BE speedo is likely to have been 3BA (nominally 0.161" diameter by 34.8 threads/inch). If you really want to keep this original, you will need to contact someplace like the folks at British Fasteners
www.britishfasteners.com
and ask see if they have any 3BA bolts/studs for sale. Alternatively you could buy a die from them and thread a piece of stock to make a 3BA stud.

Were this me, and since this is a part hidden behind the dash, I would forget originality and make an 8-32 stud. Threaded 8-32 stock and nuts are readily available by comparison to 3BA hardware.

EDIT: I just checked the British Fasteners web site. Depending on the head type you want to use, they do have long 3BA screws and nuts to match. It will probably cost you more in shipping than the hardware itself.
 
<div class="ubbcode-block"><div class="ubbcode-header">Click to reveal.. <input type="button" class="form-button" value="Show me!" onclick="toggle_spoiler(this, 'Yikes, my eyes!', 'Show me!')" />]<div style="display: none;">They are 2BA[/QUOTE]</div>

Shows I shouldn't depend on memory. Went and checked my taps and it is 3BA. Should remember, I recently made a couple hundred of the round nuts.
 
Kevin--if you are intent on keeping this stock--and I see no reason to do it, frankly--try calling British Masters. You will know their tagline as "Mountains of British Car Parts" from eBay. Usually they have these on eBay but I don't see them on there right now. Considering the number of cars they've salvaged they probably have jars full of them. 800-333-0461.

But if it was me I'd do what Doug suggests. 8-32

Charlie
 
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