The following warnings occurred:
Warning [2] Undefined variable $search_thread - Line: 60 - File: showthread.php(1617) : eval()'d code PHP 8.1.31 (Linux)
File Line Function
/inc/class_error.php 153 errorHandler->error
/showthread.php(1617) : eval()'d code 60 errorHandler->error_callback
/showthread.php 1617 eval



Austinsevenfriends › Austin Seven Friends Forum › Forum chat... v
Rist Horn Threads

Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Threaded Mode
Rist Horn Threads
Chris KC Offline
GO 6285
*****
Joined: Aug 2017 Posts: 3,394 Threads: 106
Reputation: 28
Location: Darkest Bedfordshire
#1
23-05-2018, 07:57 PM
Anyone know what thread the terminal posts on a 6V Rist horn are? 3BA perhaps?

They are a shade bigger than the 4BA screws which hold the unit together.
Reply
Stuart Joseph Offline
Senior Member
****
Joined: Aug 2017 Posts: 309 Threads: 56
Reputation: 3
#2
24-05-2018, 08:14 AM
(23-05-2018, 07:57 PM)Chris KC Wrote: Anyone know what thread the terminal posts on a 6V Rist horn are? 3BA perhaps?

They are a shade bigger than the 4BA screws which hold the unit together.
Good morning Chris, I've just tried two horns and the thread on them is 2BA.

Regards from the creative county - Staffordshire

Stuart
Reply
Ian Williams Offline
Freak
*****
Joined: Aug 2017 Posts: 1,715 Threads: 47
Reputation: 25
Location: Auckland NZ
Car type: 36 Nippy, 31 RM, 38 Special, 24 Works Rep
#3
24-05-2018, 08:45 AM
Are you sure, I thought they were coarser 5/32 whit from memory??
Black Art Enthusiast
Reply
Chris KC Offline
GO 6285
*****
Joined: Aug 2017 Posts: 3,394 Threads: 106
Reputation: 28
Location: Darkest Bedfordshire
#4
24-05-2018, 09:36 AM
(24-05-2018, 08:45 AM)Ian Williams Wrote: Are you sure, I thought they were coarser 5/32 whit from memory??

Not sure at all Ian, wild guess based on approx dia over threads ~4mm; so 5/32BSW sounds plausible. 

They are a bit manky so I want to clean them up, would be good to do it with the right die...
Reply
Stuart Joseph Offline
Senior Member
****
Joined: Aug 2017 Posts: 309 Threads: 56
Reputation: 3
#5
24-05-2018, 10:04 AM
(24-05-2018, 08:45 AM)Ian Williams Wrote: Are you sure, I thought they were coarser 5/32 whit from memory??

Hello Ian, I too thought they were courser than BA but a 2BA nut fitted both horns perfectly.

Stuart
Reply
Chris KC Offline
GO 6285
*****
Joined: Aug 2017 Posts: 3,394 Threads: 106
Reputation: 28
Location: Darkest Bedfordshire
#6
24-05-2018, 10:13 AM
Sorry Stuart (& thanks) - somehow I missed your reply earlier.

I wonder if more than one size was used? I'm pretty sure I offered up 2BA last night but it looked way too big; and that would be 4.5mm across the threads (might be more worn than I thought). I'll have to check again tonight, stuck in the office right now!
Reply
Ian Williams Offline
Freak
*****
Joined: Aug 2017 Posts: 1,715 Threads: 47
Reputation: 25
Location: Auckland NZ
Car type: 36 Nippy, 31 RM, 38 Special, 24 Works Rep
#7
24-05-2018, 10:55 AM
Interesting Stuart, I have two genuine Rist horn's here and both are not 2BA, in fact a 2BA nut goes straight over the studs 5/32 BSW is correct for mine so perhaps there was a variation.
Black Art Enthusiast
Reply
Geoff Halstead Offline
Member
***
Joined: Aug 2017 Posts: 112 Threads: 5
Reputation: 2
Location: South Norfolk
#8
24-05-2018, 12:55 PM
5/32x32tpi on mine.

Geoff - Compressed air cooler completed.
Reply
David.H Offline
Posting Freak
*****
Joined: Aug 2017 Posts: 849 Threads: 123
Reputation: 1
#9
24-05-2018, 02:08 PM
(24-05-2018, 12:55 PM)Geoff Halstead Wrote: 5/32x32tpi on mine.

Geoff - Compressed air cooler completed.
This may help (or confuse....)  
Across flats a 2BA nut should be 0.324". 1/8BSW 0.338" . (M5 nut  is 8mm ...0.315")
I think a No 6 UNC/F is 0.313 (5/16"A/Flats)
Reply
Stuart Joseph Offline
Senior Member
****
Joined: Aug 2017 Posts: 309 Threads: 56
Reputation: 3
#10
24-05-2018, 02:50 PM
(24-05-2018, 10:55 AM)Ian Williams Wrote: Interesting Stuart, I have two genuine Rist horn's here and both are not 2BA, in fact a 2BA nut goes straight over the studs 5/32 BSW is correct for mine so perhaps there was a variation.

Hi Ian, just tried a third Rist's horn and it is as you suggest 5/32x32tpi BSW, so there is (was) variation.

5/32 Whit is of course the same size as the original Meccano thread.

Regards

Stuart
Reply


Forum Jump:


Users browsing this thread: 2 Guest(s)