Thanks: 0
Likes: 0
Needs Pictures: 0
Picture(s) thanks: 0
Results 1 to 15 of 36
-
8th December 2011, 02:04 PM #1Shedaholic
- Join Date
- Mar 2004
- Location
- Chapel Hill (Brisbane)
- Age
- 53
- Posts
- 70
Sourcing or converting a backplate for 1.5" 8TPI 55deg
I have a Mars "Great Scot" lathe with a 1-1/2" 8tpi spindle.
I was told by the previous owner that this is the same as hercus and southbend, so I bought a used backplate to suit, advertised for hercus/SB. It doesn't fit. Seems my lathe has 55 deg BSW thread profile, not 60deg.
I'm trying to picture whether its feasible to chase out the female faceplate thread to make it mate, and it's doing my head in. I think its the wrong way round (I could modify a male thread but not female). Anyone tried this?
I don't have the threading gears operating on my lathe yet, so haven't done the experiment (or tried to thread a blank plate).
Also, does anyone know of other lathes (probably british or aussie) that use(d) the 1.5/8BSW spindle (brands I could search for when looking for backplates to fit my lathe)?
--chris--
The IEEE has monitored this posting and affirms that no energy was created or destroyed during its composition or transmission.
-
8th December 2011 02:04 PM # ADSGoogle Adsense Advertisement
- Join Date
- Always
- Location
- Advertising world
- Age
- 2010
- Posts
- Many
-
8th December 2011, 03:12 PM #2SENIOR MEMBER
- Join Date
- Sep 2011
- Location
- Ballarat
- Age
- 65
- Posts
- 2,659
Hi Chris,
1 1/2" x 8 TPI Is actually standard BSF. British Standard Fine. Taps and dies can be available.
Phil
Oops. Is that inch and five eights that you have written. If so, ignore everything I wrote.
-
8th December 2011, 04:47 PM #3Distracted Member
- Join Date
- May 2010
- Location
- Lower Lakes SA
- Age
- 58
- Posts
- 2,557
Mr Bigot, if you have no joy, backplate blanks are available for your machining pleasure, eg: RDG Tools - Online Engineering Tools Blank Unfinished Cast Back Plates.
I don't think you can convert American to British because 55 is narrower than 60. The other way, maybe.
-
8th December 2011, 05:14 PM #4GOLD MEMBER
- Join Date
- Jul 2010
- Location
- Melbourne
- Posts
- 7,775
I'm not so sure its that simple Bryan. I'm thinking the 55 degree thread must be deeper than the 60 degree thread. I can't find any numbers on a 60 deg 8 TPI its not UNC thats 6 tpi, UNF is 12tpi.
Stuart
-
8th December 2011, 05:29 PM #5SENIOR MEMBER
- Join Date
- Sep 2011
- Location
- Ballarat
- Age
- 65
- Posts
- 2,659
But 1 1/2 x 8 TPI is BSF
Phil
-
8th December 2011, 05:35 PM #6SENIOR MEMBER
- Join Date
- Sep 2011
- Location
- Ballarat
- Age
- 65
- Posts
- 2,659
If it is a 60 degree thread then it will be an American standard 8 pitch thread.
Phil
-
8th December 2011, 05:38 PM #7GOLD MEMBER
- Join Date
- Jul 2010
- Location
- Melbourne
- Posts
- 7,775
Isn't BSF Whitworth 55 degree?
American standard what?
-
8th December 2011, 05:38 PM #8Philomath in training
- Join Date
- Oct 2011
- Location
- Adelaide
- Age
- 59
- Posts
- 3,149
If the spindle is BSF then the thread grooves will be deeper than the crests on a UN series back plate.
As well as UNC, UNF, UNEF etc , remember that there were also UN inventions like the 8tpi series (and I think 16, 24, ...)
As you say, it's the wrong way around. the only way that you could use the backplate that you have would be to bore it out and sleeve it. You could then re-cut a 55 degree thread
Michael
-
8th December 2011, 05:43 PM #9SENIOR MEMBER
- Join Date
- Sep 2011
- Location
- Ballarat
- Age
- 65
- Posts
- 2,659
-
8th December 2011, 05:46 PM #10GOLD MEMBER
- Join Date
- Jul 2010
- Location
- Melbourne
- Posts
- 7,775
-
8th December 2011, 05:52 PM #11SENIOR MEMBER
- Join Date
- Sep 2011
- Location
- Ballarat
- Age
- 65
- Posts
- 2,659
-
8th December 2011, 05:52 PM #12GOLD MEMBER
- Join Date
- Jul 2010
- Location
- Melbourne
- Posts
- 7,775
-
8th December 2011, 06:05 PM #13SENIOR MEMBER
- Join Date
- Sep 2011
- Location
- Ballarat
- Age
- 65
- Posts
- 2,659
Hi Stuart
No, UNC is Unified National Coarse.
American Standard hails from the American Society of Mechanical Engineers. A.S.M.E.
Unified National is a derivative of this.
Phil
-
8th December 2011, 06:10 PM #14SENIOR MEMBER
- Join Date
- Sep 2011
- Location
- Ballarat
- Age
- 65
- Posts
- 2,659
Just to add to the confusion. Whitworth is pre war. When the war came along, they ran out of steel so they made the bolt heads and nuts smaller and called it British Standard Whitworth
I will stop now lol
-
8th December 2011, 07:34 PM #15Member
- Join Date
- Aug 2009
- Location
- Lake Macquarie
- Age
- 86
- Posts
- 64
[QUOTE=unixbigot;1412366]I have a Mars "Great Scot" lathe with a 1-1/2" 8tpi spindle.
My 9" Hercus Craftsman has 1.5" x 8 tpi USS (Sellers Thread) 60 degree profile.
Col
Similar Threads
-
1" female 10TPI to 1" male 8TPI adaptor
By Simomatra in forum WOODTURNING - PEN TURNINGReplies: 10Last Post: 12th January 2010, 05:22 PM -
Sourcing an 8" x 40mm 80-100 grit white wheel?
By rsser in forum WOODTURNING - GENERALReplies: 46Last Post: 30th November 2008, 11:38 AM -
Advice on sourcing 1" unhandled skew?
By Skew ChiDAMN!! in forum WOODTURNING - GENERALReplies: 48Last Post: 28th September 2007, 07:37 AM -
Sourcing " Bandsaw Handbook"
By sailor in forum BANDSAWSReplies: 9Last Post: 25th July 2007, 05:56 PM