22-02-2018, 01:47 AM
First a quick plea. When posting would everyone please use the terminology as used by Austin as found in their spare parts list. The lists are freely available to read and download in the Austin Seven Clubs Association archive section. This would make technical discussions so much easier to follow. (drag link?????? what is that????.....is it the steering side tube 1A4147 or the steering cross tube 1A4018????? and so on. 
I am just about getting to the overhaul of my Nippy special, steering.
I have a dislike for the Steering side tube and its ball pins and associated springs and thrust blocks. I believe some people have used ROSE joints in lieu of the ball pins. To save re-inventing the wheel can someone tell me what size/material tube and rose joints that have been used (I/D and O/D of tube). How were Rose joints fitted to tube (Male thread into tube with female thread; insert, with female thread, welded into tube and rose screwed in?
Really full details/dimensions and how-to-do would be appreciated.
Some car details that may be relevant.
BMC A+ engine so somewhat heavier at front. (this replaces BMC A 948 previously used)
Big 7 front axle with 1A4604 side tube leaver (some call steering arm....the arm in the stub axle that the steering side tube connects to). Apparently bigger radius means they do not crack on inside bend.
Spring shackles standard new big 7 (threaded pins rotate in threaded bush).
Morris minor cross tube leavers instead of big 7 1A4644/1A4645. The Morris leavers were tapered and keyed into their Morris housing but have had taper turned down to parallel with keyway as per big 7. They were also bent down slightly so that the steering cross tube was strait and clears under the chassis. The Morris leavers take easy to get and easily replaceable ball joints. The ball joints are standard Morris, female end screwed onto the strait steering cross tube which i threaded with a die. I don't think I had the big 7 cross tube 1A4646 and ball ends 1A4643 at the time I did the conversion, but Morris ones are better.
The current steering side tube is a pre big 7 one cut and lengthened by a sleeve welded over.
Big 7 radius arms fixed to chassis with silent block bush (housing 1A4626 and bush 2H1051)....Does anyone know the original dimensions of the silent block bush......it would seem to be the same size as the A7 rear axle torque tube socket to chassis mounting.....but that is 2H2181 in big 7 and 2H1051 in 1937 low chassis A7........I do not know if either of the bushes on mine are the correct ones. (who does spare 2H1051 bush? as that is what I will use if I can get a new one.
I have noted that on one radius arm end the inside surface is convex and the inner sleeve of the bush concave....I am assuming this is wear and both should be flat....note to self - must ensure bolt tightened up so no relative movement between arm and bush inner sleeve. Perhaps there is a modern poly bush with stainless inner sleeve that purposely rotates in bush....as per those made by Super Flex for some wishbones?
Steering box is the late A7 1A6111 with worm sector 1A6125 (only 1/3 the number of teeth) and steering arm 1A6127.
Does anyone know of a source of the thrust ball bearing.......cup 1A6131 and cage 1A6124; balls (34 of) 2K5286 or a suitable replacement. Last time I tried to find many years ago nothing was available.
Had trouble locking up on corners...embarrassing nearly going up on pavement at roundabout
Cured by use of Molyslip added to lubricant in box.
I do not have machining capabilities (or the skills) so most work would have to be outsourced. My medium sized lathe is a bit worn and only used for non critical work.
Thanks
Dennis
I am just about getting to the overhaul of my Nippy special, steering.
I have a dislike for the Steering side tube and its ball pins and associated springs and thrust blocks. I believe some people have used ROSE joints in lieu of the ball pins. To save re-inventing the wheel can someone tell me what size/material tube and rose joints that have been used (I/D and O/D of tube). How were Rose joints fitted to tube (Male thread into tube with female thread; insert, with female thread, welded into tube and rose screwed in?
Really full details/dimensions and how-to-do would be appreciated.
Some car details that may be relevant.
BMC A+ engine so somewhat heavier at front. (this replaces BMC A 948 previously used)
Big 7 front axle with 1A4604 side tube leaver (some call steering arm....the arm in the stub axle that the steering side tube connects to). Apparently bigger radius means they do not crack on inside bend.
Spring shackles standard new big 7 (threaded pins rotate in threaded bush).
Morris minor cross tube leavers instead of big 7 1A4644/1A4645. The Morris leavers were tapered and keyed into their Morris housing but have had taper turned down to parallel with keyway as per big 7. They were also bent down slightly so that the steering cross tube was strait and clears under the chassis. The Morris leavers take easy to get and easily replaceable ball joints. The ball joints are standard Morris, female end screwed onto the strait steering cross tube which i threaded with a die. I don't think I had the big 7 cross tube 1A4646 and ball ends 1A4643 at the time I did the conversion, but Morris ones are better.
The current steering side tube is a pre big 7 one cut and lengthened by a sleeve welded over.
Big 7 radius arms fixed to chassis with silent block bush (housing 1A4626 and bush 2H1051)....Does anyone know the original dimensions of the silent block bush......it would seem to be the same size as the A7 rear axle torque tube socket to chassis mounting.....but that is 2H2181 in big 7 and 2H1051 in 1937 low chassis A7........I do not know if either of the bushes on mine are the correct ones. (who does spare 2H1051 bush? as that is what I will use if I can get a new one.
I have noted that on one radius arm end the inside surface is convex and the inner sleeve of the bush concave....I am assuming this is wear and both should be flat....note to self - must ensure bolt tightened up so no relative movement between arm and bush inner sleeve. Perhaps there is a modern poly bush with stainless inner sleeve that purposely rotates in bush....as per those made by Super Flex for some wishbones?
Steering box is the late A7 1A6111 with worm sector 1A6125 (only 1/3 the number of teeth) and steering arm 1A6127.
Does anyone know of a source of the thrust ball bearing.......cup 1A6131 and cage 1A6124; balls (34 of) 2K5286 or a suitable replacement. Last time I tried to find many years ago nothing was available.
Had trouble locking up on corners...embarrassing nearly going up on pavement at roundabout
Cured by use of Molyslip added to lubricant in box.I do not have machining capabilities (or the skills) so most work would have to be outsourced. My medium sized lathe is a bit worn and only used for non critical work.
Thanks
Dennis