Thread: Replacement screw for fence on old Stanley 78 rabbet plane

I've found Bunnings, and other places sell imperial bolts poorly cut.
I've one, will have a look later when going to workshop.
It'd be imperial.
Is there a chance the thread is cactus? Reason the screw fell out?
If so have you a tap to run slightly larger thread?

Originally Posted by Avondale

I've found Bunnings, and other places sell imperial bolts poorly cut.
I've one, will have a look later when going to workshop.
It'd be imperial.
Is there a chance the thread is cactus? Reason the screw fell out?
If so have you a tap to run slightly larger thread?

Agree it would be imperial. But so many different thread pitches who knows if it was standard. The thread itself looks fine - can’t see any burrs or anything like that. I’m guessing the original screw was simply lost.

Thanks

Is your No. 78 a USA made plane or English?

I believe they used different pitches for those fence screws.
The English ones also differ additionally depending on their age.

I'd compare my few 78s screws for you but they are packed away at the moment.

Originally Posted by dubrosa22

Is your No. 78 a USA made plane or English?

I believe they used different pitches for those fence screws.
The English ones also differ additionally depending on their age.

I'd compare my few 78s screws for you but they are packed away at the moment.

It’s an English one. Not sure how to tell the age though. Will look for any markings.

Mine is a No 45
Checked all wing nuts. All same
No BA or Witworth equivalent
I tried all options.
Nearest size whitworth tap had No 10 stamped on it. Drill size?
It started and kept going but definitely wasn't right 1707531517151-1.JPEG
A thread pitch gauge that was nearest neat fit was 28

I'm no expert, just got all dads and his dads stuff, ex Nottingham so definitely British.

Did a bit of googling forums
Couple comments below
Stanley planes are notorious for non standard thread sizes

Based on my observations I wonder if this screw is in fact a 10-28. Stanley may have used odd thread sizes, but they were very self-consistent. Even this odd screw/thread seems to have been used in many different parts.

10-28 tallies with my uneducated observation with a No 10 drill and 28tpi.
If that makes any sense

I did find ebay sells such https://www.ebay.com.au/itm/26587987...rid=705-139619
For mine at least but can't see they'd have been different across similar planes

Might be tough to find a replacement. i did see the eBay ones but they are expensive! If I try and re-tap it, I guess I would need to go big enough to fully remove the existing threads?

I've got an English 78, not certain of its age, but likely 1950s or thereabouts. I just went & checked & the fence & depth-stop screws are the same diameter (.176") & the pitch is 28tpi according to my thread gauge, so looks like it's a 10-28, as suggested.

The English Stanleys followed the American originals for a long time, but they started changing things in the 70s or 80s with their bench planes, going to metric by the 90s. No idea if & when they changed threads on the rebate plane.

Cheers,

Hi All

Ahh Stanley threads, a perennial problem.
Sources of 10-28 - ebay as mentions - broken Stanley 78's but also broken - 151 and 153 spokeshave's which used the 10-28 but I suspect other spokeshaves used them as well. I have a couple of Stanley 78 fences in my box of Stanley parts, so if you retap and somehow find a 10-28 thumbscrew you could ask for another fence- I have a bad habit of purchasing Stanley parts when I stumble on them and the price is in pennies.

But here's what's likely the best option Amazon.com and purchase some thumbscrews and rethread.

Regards

eBay is more economical https://www.ebay.com.au/itm/15349081...Bk9SR9jkk6ayYw

almost tempted to buy one myself but no pressing need...

Thanks. Dumb question but what is the “10” in 10-28?

What if I just retap slightly larger with a more standard thread size?

Edit: 10 is a #10 screw (3/16”)

It's a "numbered drill size"
Drill SizesDrill ~ Inch ~ mm
11 ~ 0.191 ~ 4.85
10 ~ 0.193 ~ 4.90
9 ~ 0.196 ~ 4.98
8 ~ 0.199 ~ 5.05
I gather from what dad said it's the appropriate sized drill for a particular tap.
I've got a range of numbered drills, even a cast drill holder somewhere.

As for retapping. Yes I'd suggest that's an option worth pursuing.
I'd just barge in and pick a close next, readily available size.
I'm a woodworker, not a metal worker

It's a ticklish situation, 'cos looking at my thread chart, that thread pitch is a real outlier! A 'standard' #10 UNC or Whitworth thread has a pitch of 24tpi & recommended drill size of 3.8mm (coarse) & 4.1mm for the UNF thread (32tpi). Simply running a standard #10 tap through the existing thread will most likely end up with a mess, so that's not an option.

Finding an original-size thumbscrew would be the simplest solution, but hen's teeth are probably more common! If you wanted to convert to a common (very common!) thread size, I think your best bet would be to go up to M5. That has a recommended drill size of 4.2mm, which should remove most of the original thread & give you a clean & usable thread after re-tapping. Looking at my fence, there is plenty of 'meat' to take the increased size.

The 78 is a bit of a nuisance - virtually any old example you come across has long since parted ways with its "loose" bits, either fence or depth stop (or more often than not, both) &/or their associated screws. It would make life so much easier for those who wish to get them back working if Stanley had opted for a thread size stocked by modern hardware stores!

Cheers,

10-28 comes under the Unified thread series as a UNS, meaning Special.

UNS Thread ASME B1.1-2003

Tap and die sets are actually fairly easy to come by; Ebay and Aliexpress do them for under $15.

It would be nice if 12-20 was as easily and cheaply obtainable... this is the weird size Stanley used on their bench planes for handles and knobs...

Originally Posted by Chief Tiff

It would be nice if 12-20 was as easily and cheaply obtainable... this is the weird size Stanley used on their bench planes for handles and knobs...

Genie of the internet grants your request https://www.ebay.com.au/itm/12630191...3ABFBMoomap7Jj

regards