What's new
What's new

F.E Reed large change gear identification

Patricknagle

Plastic
Joined
Oct 18, 2023
I’ve got a very old F.E Reed lathe (1890’s from what I can tell) it’s a very nice old lathe and it’s in pretty good shape overall. The problem is that I’m missing most of the threading/feed gears which I would like to 3d print or have machined the problem I’m having designing the gears is I don’t know the pressure angle and don’t have any great way to measure it at the moment, if anyone knows what might have been standard on something like this that that info would be greatly appreciated.

Any help or info on the machine or specifically the gears would be greatly appreciated.

Another note is I’ve been unable to find a model with a similar or identical apron all the examples I can find are slightly differently most notably most models of this size did not include power cross feed from what I could find.


Lathe specs:

Brand: F.E Reed lathe

DOM: 1890-1900

Swing:10in

(Has power cross feed)

If I missed anything let me know and I’ll post pictures next time I’m in the shop
 

Attachments

  • 1C06DB19-ABE5-4EAF-8DCC-39A55E69AAEE.jpeg
    1C06DB19-ABE5-4EAF-8DCC-39A55E69AAEE.jpeg
    2.8 MB · Views: 26
  • B932EFA3-0094-4402-B082-02214999C73C.jpeg
    B932EFA3-0094-4402-B082-02214999C73C.jpeg
    4.5 MB · Views: 25
  • CB8016D2-358D-4FF0-97BA-941A6DE125E6.jpeg
    CB8016D2-358D-4FF0-97BA-941A6DE125E6.jpeg
    1 MB · Views: 27
  • 7AFAE1CE-988D-433B-A7DB-FFAFE9847C92.jpeg
    7AFAE1CE-988D-433B-A7DB-FFAFE9847C92.jpeg
    895 KB · Views: 25
  • E8A1902E-E9DF-4BB4-99AF-E40B8D4269F8.jpeg
    E8A1902E-E9DF-4BB4-99AF-E40B8D4269F8.jpeg
    1 MB · Views: 24
  • B63DE56B-9E9C-4F76-AD8B-6EB28D35C9B6.jpeg
    B63DE56B-9E9C-4F76-AD8B-6EB28D35C9B6.jpeg
    1.8 MB · Views: 28
  • 0EC9C043-E252-4199-A057-92354191F5A6.jpeg
    0EC9C043-E252-4199-A057-92354191F5A6.jpeg
    2 MB · Views: 28
Handy book from those days is A Treatise On gear Wheels by George B. Grant, and is one of the fairly recent reprints by Lindsay.

Fairly decent photo comparison 14 1/2 to 20 degree. Plainly the 20 has more "beef" at the tooth's base compared to 14 1/2. It would be just about a "given" that your lathe was fitted with 14 1/2 - that is what was in vogue - overwhelmingly


As to cross feed or not, the 1901 M,M&M catalog says the cross feed was left off on Taper Attachment lathes
 

Attachments

  • Reed from 1901.jpg
    Reed from 1901.jpg
    460.7 KB · Views: 3
Last edited:
I took a look at that book and it looks like it will have some pretty useful info. It’s even got gear profiles printed in scale for comparison to pre-made gears and some numbers and other info more relevant to the time period.

Thanks for the recommendation!
 
With 20dgr you have less undercut
If all gears are missing it does not matter 15 14,5 or 20 dgr
I would pick 20dgr then More common (so cheaper)and less undercut on small gears

Peter
 
With 20dgr you have less undercut
If all gears are missing it does not matter 15 14,5 or 20 dgr
I would pick 20dgr then More common (so cheaper)and less undercut on small gears

Peter
I suppose I should have been a little more clear in my original post my apologies but I still have 3 of the original gears a 28,96 and 112 tooth gear but I’ve been thinking and wondering if I only have 3 originals then I might as well just make a whole new set of change gears with more standard pitch of 20
 
If I were to remake an entirely new set of gears for threading what would be the important values I need to keep. Just tooth width/tooth height, tooth spacing and tooth count? (from the original thread chart)
 
How many gears you need?
I would buy them
They are so cheap I never mess around with making my own
Gearpitch is determend with Diametrical pitch (Or Module in the rest of the world)


Peter
 
I only need enough gears for the more standard thread pitches like 8,10,24,32 tpi so somewhere around 8 gears
 
Also how would one go about determining the diametral pitch of the original gears?
The diametral pitch (DP) is equal to the number of teeth plus 2 divided by the outside diameter. For example a 40 tooth gear with an OD of 2.33" has a DP of (40+2)/2.33, or 42/2.33, or 18.02, rounded to 18 DP.

Irby
 
Thanks to everyone for the info, next time I’m in the shop I’ll take some measurements do the calculations, put em in cad then print and compare to the old gears

Fingers crossed 🤞 everything meshes correctly
 
Google base pitch tables and you can find how to determine the pitch and the pressure angle by measuring over successive spans of teeth. It is very easy and foolproof.

I agree it is very likely 14.5 PA, and also it is likely you can buy stock gears and mod the bores much cheaper than making blanks and having teeth cut.

You may luck out and find someone parting out a lathe. Or ebay. Of course it doesn't have to be the same lathe.. Maybe post on the wanted forum here. Most of us hate to discard useful stuff, and love to see it go to a good home.
 
I’ll look around a bit on eBay or facebook marketplace for someone parting out an old lathe and see if I can grab some gears.

Thanks again to everyone for the help
 
If you want to try and decide what pressure angle your gears are, I have an Excel spreadsheet I wrote back in 2007 that calculates the shape of the gear teeth given the pressure angle, DP, number of teeth, etc. Here's a comparison of a 20 and 14.5 degree 40 tooth, 18 DP gear. The dimensions are in inches, the "Y" being from the gear center.

tooth profiles 20 and 14.5 degrees.jpg

If you figure the DP of the gear pointed to in this photo - it looks to be in decent shape - and post it, I can try to mill out a thin piece of aluminum or brass stock in the shape of both teeth for you to try to fit into that gear. If one fits better, then it may determine the pressure angle. It looks close to a 40 teeth, 18 DP gear, which is what the change gears were on an old 1890's 12" F.E Reed lathe I once had.

-1F5A6.jpeg

Irby
 
That’s I good idea although I’m beginning to lean towards the idea of just making an entirely new set with a diametral pitch of 20 for simplicity sake.

I’m not not sure what I’m gonna do about the compound gear on the 2nd stud I think I’ll make a new 4 position thread chart where I get a choice over the teeth on each side of the compound gear as a posed to what I think would have originally been done which is have the 2 gears cast as one piece.

Either way I’m gonna have to make some new gears luckily I still have some bronze left over from another project to make bushings for the inside of the new plastic gears.

I’m gonna 3D print some example gears in different diametral pitches and see what gears mesh the best and I’ll go from there.

Thanks for the tips!
 
I’ve got a very old F.E Reed lathe (1890’s from what I can tell) it’s a very nice old lathe and it’s in pretty good shape overall. The problem is that I’m missing most of the threading/feed gears which I would like to 3d print or have machined the problem I’m having designing the gears is I don’t know the pressure angle and don’t have any great way to measure it at the moment, if anyone knows what might have been standard on something like this that that info would be greatly appreciated.

Any help or info on the machine or specifically the gears would be greatly appreciated.

Another note is I’ve been unable to find a model with a similar or identical apron all the examples I can find are slightly differently most notably most models of this size did not include power cross feed from what I could find.


Lathe specs:

Brand: F.E Reed lathe

DOM: 1890-1900

Swing:10in

(Has power cross feed)

If I missed anything let me know and I’ll post pictures next time I’m in the shop
hi i can't help you but just wanted to say that i really like your machine!! good luck.
 
Gosh guys. Do yourself a favor and GOOGLE BASE PITCH TABLES!!!!!

I did it for you.


Basically you measure successive tooth spans, i.e. 3, 4, 5 teeth, and figure the average difference. This difference is the base pitch. Base pitch is unique for each PA and pitch, be it DP, CP, or MOD. Look up the difference in the chart and Bob's your uncle. No muss, no fuss! The caveat is you have to measure over the curved tooth involute so very large tooth number gears can't be measured because the tooth profile approachs a straight side.

The other option is to mess around A LOT and waste a lot of time and maybe kinda sorta know about approximately what you have.
 








 
Back
Top