I'm in need of a #5 x 32 tpi flat head slotted machine screw, 1/2" long. Prefer steel but brass will work fine. I could tool up and make some but I only need one, so I'm hoping that maybe someone can look through his stash and come up with one. Thanks to anyone who gives it a shot!!
I seem to remember that 5x32 is a thread used on firearms, might check brownells and see if they have any of those.
just search for Brownells on google, the other place id check is e-gunparts.com alot of Guns used some oddball fasteners.
RV I was interested in your description of the machine screw you want. I presume it is not a countersunk one, rather a head with vertical sides. In Australia we call that a cheese head screw, cylindrical like a cheddar cheese wheel.
We also use a different description for what you call an oval head screw. Here it is a raised head countersunk screw. When I first read of US oval head screws I was bemused by the thought that a screw would have an oval head rather than a round one, and mystified as to how it would sit in a countersink.
And still we try to speak the same language!
Allan from down under.
It's a flat slotted head, shown furthest on the right in Art's photo.
I will try the firearms route, but will probably have to go out of state because now in NY, a bolt can't have more than 8 threads or it's illegal.
5-32 is not an ASME thread. Probably predates ASME.
Now let me guess. Is it for a coil?
The original ASME standard was adopted in 1907 to replace the private standards
used by some of the screw manufacturers. I have no way of knowing how far back
the compiler of the master thread chart, (of which this is a small section) went to with
the included size ranges. It does however include sizes that are missing in the ASME
chart in the 1942 Machinery’s Handbook. That 1942 chart does however include a
column with some of the older private sizes used by some manufactures.
The 5 x 32tpi size is shown there.
I just thought that while I was posting the different head styles, that the chart, which
included the in depth info in both inch and metric dimensions of the most likely number
sizes that one may still encounter may be of use to some members.
Yes, I agree, and more importantly, Ford did not always use ASME thread on the Model T. There are parts of the Model T which have the same threads per inch and the same diameter as some ASME threads which are not ASME threads! So just because you see a certain thread listed on the ASME chart and can guage a fastener to match does not mean you can order an ASME tap or die of that specification and expect it to match.
Semantics my friend! ASME undertook to reduce the number of threads in common use at the time. Yes, you are correct on that the sizes existed from years earlier and lots more of them.
But what ASME also did was to define more than just Size and TPI (threads per inch) where previously there were games played and 'house standards' as to thread cutting so that 'my screw went in tighter than yours' and 'my screw went in quicker and smoother than yours'(Just like gear cutting to have a unique situation to cause your aftermarket gypsies fits that later gave AGMA its' need to be.)
Now to make matters worse, Ford was under no requirement to conform! Standards were voluntary with a little of the shaking of the trees in WW1, and further (now universally final) shaking of the trees in WW2. Ford 'may' have complied, Ford 'probably' complied, but we have no knowledge on that (I have NOT looked at every screw and bolt drawing with a T number)
Ford may have used different tap drill sizes, Ford may have used a more rounded root, and for that reason I always suggest a tap be run in some of this old stuff before trying a 'new' bolt or screw. The older it is, the more you just might 'need' it. Old man's paranoia, I know, but I don't twist screws and bolts off and blame it on the Chinese! I would 'guess' and only a guess that once Ford went to rolled threads on most things in '23 or so that by then they were using 'someones' standard, but that's only a guess.
I'll disagree with Royce a little bit here (surprise), his words are correct technically to the decimal place...yet what else to do? Run in a modern ASME tap and have a modern ASME screw and unless Ford used a much smaller tap drill (doubt it, I always question did they go too big on tap drill) you have reformed what you have to the best it could do.
As Art points out, the ASME approved chart went much farther in 'size' and 'TPI' and in fact next time posted throw in the #14 as there is a good one that haunts us in the repop flywheels that exist
Point well taken.
I've run into this situation on antique cars (not just Model T's) several times, and yes that is what I did, not wanting to waste a lot of time finding some arcane obsolete tap somewhere to match an arcane obsolete screw that I also did not possess.
In RV's case I understand he is shooting for absolute correctness which is always an admirable goal.
Hi George and All
Here are the specs for the # 14's, and to make things complete I added the 0-80 and the larger sizes as well.
Yes, Larry; it's for a coil. Not anything that Ford ever used. Three are required and the slots on #3 got all chewed up over the years so I really should have a new one for the most secure hold. It threads into bakelite, so a controlled cross threading wouldn't work well and would cause a loose fit and/or crack the material.
R.V. Maybe you should weld up the old slot and cut a new one.
Not to sound crude!
Use a 6-32 tap and make this attempt and future attempts less challenging!
5-40 screws are commonly available. I have several styles that are used on the Weston HCCT meters.
Steve, I thought about that, and it could be done if the head is re-sized to a #5; also, I have a lot of #5 x 40 screws on hand in all different lengths, but what I'm hoping for is the simplest solution: that someone can come up with the right one.
I think the coarse thread series was originally the Sellers profile, which became the United States Standard Thread in the 1880's. The fine thread series was originally the SAE thread, Society of Automotive Engineers. Current threads are a Unified Standard Fine and Unified Standard Coarse, UNC then there are also some UNS threads which have "non standard" tpi. The Unified series began when the root of the thread was changed from a flat to a radius. The threads with a flat at the root were National Fine, NF and National Coarse, NC threads.