1 of 1- ferulebezel
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Royal KMM screws thread count.
After rooting around for dropped screws and having a long hatred of slotted screws, I've decided to replace every screw I remove with an Allen or Torx one. The problem is that the local hardware stores don't carry screws for anything smaller than a house.
I managed to get the diameters with my yard sale calipers and no training on using them. Anyway I found #s 4, 6, 8, and 10. The problem is that they have a high thread count that I've never seen.
Could someone tell me what the thread counts are?
- ChrisMacgyver
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Re: Royal KMM screws thread count.
I don't have any values, but would do the following:
Get a caliper and find a reasonably long screw (which is screwed in). The longer the better.
Unscrew it to a fraction of the base measurement unit you have (e.g. Inch, metric etc.) and measure with the caliper. Important is you zero the caliper first between the surface and the head of the screw.
Count the numbers of full turns.
Extrapolate the number of turns. If you can unscrew one inch the counts directly mean threads per inch. Otherwise (e.g. 1/2 inch unscrewing) you double it.
Happy typing
Chris
- Pete E.
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Re: Royal KMM screws thread count.
My local ACE hardware and Tru-Value hardware stores both have an aisle where they are all sorts of small SAE and metric screws, nuts, washer, etc. in very small sizes.
They are located in self-serve small pull-out drawers in those aisle.
.
- skywatcher
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Re: Royal KMM screws thread count.
Hi Ferulebezel
Typewriters like early Harley Davidson motorcycles and Briggs & Stratton engines used a lot of now discontinued threads. On these machines, 1/4"-24 was regularly found on American built machines up until the 1960's, if not later. I had to buy a #10-36 threading tap for cleaning up threads in carburetors and #4-44 for some of the governor linkages.
Because many of these threads are now obsolete, I don't think you're going to have much luck finding modern replacements for the various screws. The only supplier of screws that might fit vintage typewriters would be a gun smithing supply company.
When working on these typewriters, a completely clean and clear work area is a must so any screw that gets dropped cannot find its way to the floor. As for the slotted screw heads, no other means of driving small screws had been invented when these machines were built, but for the exception of Robertson which never caught on in the USA as it was a pre World War One Canadian invention. Hope this gives you some food for thought,
Sky
We humans go through many computers in our lives, but in their lives, typewriters go through many of us.
In that way, they’re like violins, like ancestral swords. So I use mine with honor and treat them with respect.
I try to leave them in better condition than I met them. I am not their first user, nor will I be their last.
Frederic S. Durbin. (Typewriter mania and the modern writer)
- branzino
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Re: Royal KMM screws thread count.
To determine the thread size of a screw you can use a screw thread gauge. You can find them for under $10.
- branzino
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Re: Royal KMM screws thread count.
Dropping small parts, especially small springs, is a real nuisance. About half of the time of my watchmaker training was spent looking for small parts on the ground. And finding things that others lost :-)
Working on the middle of your workbench, and not on the edge, good lighting and most of all patience, help a lot.
And a screwdriver with clips.
- ferulebezel
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Re: Royal KMM screws thread count.
branzino wrote:
To determine the thread size of a screw you can use a screw thread gauge. You can find them for under $10.
I saw that and it has threads that were never made. I got a different one and and found that they are #4-10 all 40 tpi and 1/4-24 for the feet and extra holes in the base.
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Thread Starter- ferulebezel
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- Registered: 19-8-2023
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Re: Royal KMM screws thread count.
Dropping small parts, especially small springs, is a real nuisance. About half of the time of my watchmaker training was spent looking for small parts on the ground. And finding things that others lost :-)
Working on the middle of your workbench, and not on the edge, good lighting and most of all patience, help a lot.
And a screwdriver with clips.
I don't think they jade screwdrivers like the one you pictured for decades. I do have it in a big tray on the table, which hasn't helped much.
The screws I want to replace that I haven't dropped are the set screws. One has half the slot broken off. They are all 8-40.
- •
Thread Starter- robmck
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Re: Royal KMM screws thread count.
I've found screwdrivers like this on ebay and antique stores. I also like to use H.J.J. screw starters (3 - Vintage HJJ Co. Brass Screw Starters Machinist Tools | eBay).
