How to provide lubrication to the brake Cross-shaft.
1130 forum posts
Need ideas please.
All three double cone bearings where solid with road gunk and rust, the shaft hanging down from the chassis under the car thus open to the elements.
Also need to think of a way to protect said bearings by some sort of covering.
The chassis is upside down, just having given it a coat of Jotamastic 87 Aluminium DTM epoxy paint to be followed by a coat of bitumous black.
The centre bearing is the same as the other two.
The shaft is hollow, being 24in long, thin end 1"Ø, thick end 1.1/4"Ø with the bearings at 1.1/4" centre height to the chassis, the body of the car being 4ft 4in wide, so not easy to get at.
Video of centre bearings
More photos in the Austin Seven Album.
Geoff - iOS9 is an effing disaster for me & Apple won't let me downgrade, the %^#*s!
Edited By OuBallie on 05/11/2015 13:01:33
1130 forum posts
Progress on the car can be viewed.
The centre bearing and the Centre Member where added late in the Seven's production run.
The original 1" shaft was found to be bending, so the OS section from outer bearing to just past the inner one, was increased in diameter by the addition of two extra tubes over the original, thus the difference in bearing sizes.
The bearings have zinc inserts pressed into them.
Brakes are cable operated.
Steve Jobs would never have allowed the release of iOS9.
Geoff - Can you tell that I hate iOS9 and Apple right now, should calm down, but still no heating
|Martin Kyte||05/11/2015 14:02:34|
|1404 forum posts|
I can see what you mean but are you really going to expose that little car to all weathers? Maybe a shield to reduce exposure would be more appropriate than trying to do a complete bearing seal, that or gaters on the shaft. Nice interesting project though.
|Gordon W||05/11/2015 16:30:49|
|2011 forum posts|
Long ago when I had 7's and ford pop etc. had the same problems. Usually just bunged in as much waterproof grease as possible. In the day weekly greasing was the norm. Fit nipples if none provided. I find best grease is a green castrol found in boat chandlers. Use this on 2cv king-pins.
|Nicholas Farr||05/11/2015 18:57:29|
1810 forum posts
Hi Geoff, forgive me if my theory is wrong, as I know nothing about your Austin 7 or any cars of this period that may be similar. However, in your video you say you have one bearing that moves smoothly and one that you can only move if you wedge the two halves apart. These look like self aligning bearings to me, maybe afore runner to a plummer block ball bearing, where the bearing swivels in the housing and therefore allows easy lining with a mating bearing, just in the same manner as your brake shaft. My point is, that these should not swivel easily as you need the shaft to rotate in the bearing and not drag it round. I'm guessing that the one you say moves smoothly has at some time seized up and has made the bearing turn in its housing and over time has worn the swivelling action to a point where you can move it with your fingers.
Of course I maybe totally wrong, but I've dealt with many different types of self aligning bearings in my day job and none move as easily as the one you show.
|Steve Withnell||05/11/2015 19:21:09|
789 forum posts
You're lucky. My Dad's 1930 Singer Junior has a little tray under the carburettor to stop petrol dripping on the exhaust manifold. The intent being it evaporates before overflowing...
|Phil Whitley||05/11/2015 19:25:58|
|824 forum posts|
I think you are right Nick, Oubailie, can you not make a leather pouch (ooh er missus) that will tie round the shaft and enclose the bearings, the movement is limited, and if you only want to keep the muck and weather out of it, it should be fine. 2CV again, I made some for the knife edges on the suspension, filled them with grease and tied them round with a leather thong (here we go again) worked like a charm, and when I had to change a spring box three years later, the knife edges were like the day I put them in.
|Speedy Builder5||05/11/2015 20:52:50|
|1717 forum posts|
Geoff, so its worked OK for the last 80 years - are you sure that petrol will be around in another 80 years time? - Just replace with the original spares which are available. I think the zinc bearings were white metal. The bearings must be self aligning to allow for the chassis to flex as I am sure you know but perhaps others didn't.
|James Alford||05/11/2015 22:21:56|
|341 forum posts|
A friend of mine repairs and restores Austin Sevens, builds replicas and manufactures new parts for them. If you need any advice, you could always give him a try. His details are Ian Tillman, www.oxfordshiresevens.co.uk or 07743 263791.
|Phil P||05/11/2015 23:33:52|
|458 forum posts|
Been there, got the tee shirt so to speak.
I could not bring myself to carry on using those bits of pressed tin as bearings, so I made some radical changes which give the shaft a much better chance of operating correctly, this has been in place for nearly 20 years now and has given no further trouble.
I will let the photo's do the talking and answer any questions if any crop up, sorry the photo's are a bit poor, but digital camera's were not as good back then.
Note the addition of a grease nipple to fill the gap between the shafts so water stays out.
I also took great care to get the brake drums trued up as well.
Edited By Phil P on 05/11/2015 23:34:28
1130 forum posts
Well, I was hoping for some ideas, but didn't expect this response!
Thanks guys for all the suggestions
I certainly won't be taking her out in winter, what with our salt laden roads, but it goes against the grain to see such bearings in the all-together.
I like your suggestions, so will be mulling them over and playing with bits of card whilst I do the bodywork.
I do have a tin of waterproof grease I intend using on exposed parts, but thanks for the suggestion nevertheless.
That shaft only moves a few degrees, as it has all sorts of gubbins and levers secured to it, details in Phil P photos 6 & 7, and as mentioned by SB5, the airings need to accommodate the chassis flexing.
I have no idea what was designed to rotate in what, but hopefully Phil will be able to enlighten me/us.
Been thinking along those lines.
Can grease come into contact with the leather without damaging it?
Petrol/diesel cars will no doubt be museum pieces in 80 years, but as usual I am no doubt going over the top in trying to protect those bearings, but that's me. Get it from my parents who where perfectionists.
Bl@@dy annoying this trait at times when inappropriate.
Zinc has been mentioned on the Friends Forum, so just going on what I read. Open to correction of course.
Thanks for the link.
The big diameter OS tube on my shaft will not come off as yours has.
It appears to be pinned to the long inner one.
Have read everything I can find on these shafts and there is conflicting info as some say the shafts are welded to form one solid ones, then some saying the outer tube is free to rotate slightly, so I am totally confused.
Nice mod to the shaft, but are you still using the double cone bearings?
I do like the way you have set-up the drums for skimming, so something to copy.
Photo of the tubes that make up my Ruby's Cross-shaft, there being a pin spanning the tube/s and possible outer ends visible on the outside, so mine appears to be locked solid.
As can be seen, the OS tube has been turned down to slide over the middle one, itself being turned down as well.
Confused as I said, so nothing new then.
Geoff - I could go on forever about iOS9 but won't bore everyone from now on.
|Phil P||06/11/2015 15:47:06|
|458 forum posts|
If your outer tube is solid with the main shaft, you will not be getting any compensation effect to balance the front and rear brakes, I would investigate further to see if you can part them, or get some replacements.
Everything on mine needed re-bushing and new pivot pins etc to get the brakes as they should be.
|455 forum posts|
Hi OuBallie, looks like u may b able to use a CVJ gaiter, (Constant Velocity Joint) these are available in singles thru flee bay.....
the ones I use are a back silicone rubber, about £7.00, cuttable for different size shafts...as it happen these fits the majority of cars from 1960 to date......I've been fitting these for 5 years and never had a failure......
On my old car, 1928 Citroen C4, I use a st/st strapping clip, to look smart instead of the usual plastic tie clip to fix them in place....
hope this helps....any more info PM me .....Clogs.......
|martyn nutland||06/11/2015 16:49:34|
|95 forum posts|
I can't claim intimate familiarity with ARQ Ruby brakes, but I have two vintage Austin Seven chassis and have thought long and hard about the vagaries, inadequacies and general bad design of the braking systems.
As you would know the early cars have an uncoupled layout, and to a greater extent than on your car, there is a problem concerning the rigidity of the cross-shaft. Also there is no effective way to lubricate it and, like you, I thought this latter point unsatisfactory.
To address both issues, I decided to try to strengthen the cross-shaft and support it in proper bronze bushes at each end, instead of the original wrapped 'tin-foil' types lining the flimsy brackets riveted to the underside of the chassis side-rails. If you are interested, you can read in detail on my website (martynlnutland.com 'engineering' in the drop-down menu) what I tried, but in a nutshell I made solid spigots to insert in each end of a new cross-shaft, cut journals on these and supported them in proper bronze bushes inserted in the chassis brackets. Where this may be relevant to your predicament, is it enabled me to fit grease nipples in the latter and regularly pump grease into the bushes.
While I've never owned a Ruby, I do have a chassis frame of that type. Looking at it this morning I could see a number of places where one might consider fitting grease nipples to advantage. I think that may kill several birds with one stone for you.
Clearly, and wisely, you are worried about muck and grit harming the 'works'. Yet, being a sensible chap, you won't be using an Austin Ruby other than minimally and on high days and holidays! Thus, if we adopt the traditional practice of pumping in grease until fresh appears 'in the gap', the old lubricant coming out will carry away the muck. (I passed some of my mis-spent youth doing this for the king pins, and indeed, brake mechanism, on my father's Austin Sixteen.)
And that said, I wouldn't worry too much about gaiters or other elaborate measures to protect the structure from dirt. Sometimes we have to accept that if an engineer of the calibre of Herbert Austin didn't think it necessary it wasn't, and, by the same token, if he did, we should play it by the book!
|75 forum posts|
As the rotation of the shaft is only a few degrees, how about using bonded rubber bushes, the sort that have outer and inner steel sleeves bonded to the rubber. These can be flexible in torsion but radially stiff. Just an idea.
|Phil Whitley||06/11/2015 22:21:54|
|824 forum posts|
Hi Oubailie, the grease does not harm the leather at all, seems to keep it supple!
|julian atkins||06/11/2015 22:54:51|
1196 forum posts
my dad had an old Austin 7 Ruby.
no one has yet commented upon upgrading the brakes themselves from the original design. i gather this is nowadays quite common.
|Phil P||06/11/2015 23:34:15|
|458 forum posts|
A few people have converted from cable to hydraulic brakes, but without exception have complained that they are too vicious and lock the wheels too often, some have been converted back to cable again.
If the cable brakes are in tip top condition, and more importantly been set up correctly, then they are fine for most people who drive an Austin 7 on todays roads, if you are wanting to enter competitions then it might be a different story.
The foot brake pedal operates the cross shaft which has a front to rear compensation toggle, if you find that the foot brake is not slowing you down enough, then simply pulling on the hand brake gives you exactly the the same four wheel braking but with around twice the leverage.
|martyn nutland||07/11/2015 07:26:47|
|95 forum posts|
I've taken hydraulic conversions back to what Austin intended myself, and I would be interested in what you think of my idea for the uncoupled vintage brakes. (Described on martynlnutland.com under the drop down 'Engineering'.
Of course, the fundamental point is that safety is all, and although you are correct when you say that a perfectly maintained and adjusted system on the later Austin Sevens can cope with modern traffic it depends rather heavily on skills many modern motorists do not have. I.e. a finally honed sense of anticipation and use of the gears in slowing (actually frowned upon these days by the experts) etc.
That said we do need to recognise that the Austin Seven braking system is notoriously poor. Some would say, virtually non-existent; but that is a bit of an exaggeration! Swerve don't stop, eh?
All the best.
1130 forum posts
You have put a lot of work and thought into your website. I like it!
You do not appear to be using the double-cone bearings.
If so, how does your shaft accommodate chassis twist?
How does it compare with the original shaft?
From your site, I take it you have a pre-30s Seven?
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