Wednesday 26 December 2012

POST 45 - DECEMBER 2012 - EARLY LEARNING

A few days ago I was chatting to an acquaintance deeply involved in the Classic Car Concours scene.   I went to some lengths to explain what I hoped to achieve with this particular restoration and the reasoning behind the many upgrades.  He was clearly a little puzzled and asked, when did this urge to modify and hopefully improve bits of machinery first manifest itself?  Had there ever been a time when I felt truly content to the point of simply, riding, driving and enjoying whatever mode of old bike or car transport I owned at the time?
Looking back, I had to say, as far as I could remember, probably never.


Aged about three.  I am pretty sure that the Britool
ring spanner in the picture is the same one I borrowed
from my dad many years ago and still have and use.
This conversation spurred me on to dig out a short piece I wrote quite a few years back and illustrates the point rather well :

In 1961 I was 13 years old and a keen member, possibly even a founder member of the local track bike riders club. Not formally recognised as a club (not even by its members) it never the less had a quite definite set of rules and hierarchy.  It was I think the same year that I distinguished  myself by riding from home to school (about a mile) entirely on the back wheel of my very tatty old black bike.  Also in that year, I remember that success in the 11 plus exam had rewarded a friend with a brand new Raleigh Blue Streak Racing Bike.  A similar inducement from my parents had failed.  I suppose somewhat piqued, I couldn't help but remind him that his pride and joy was named after a failed ballistic missile design.  

With my new status as a teenager (just) it was obvious that something needed to be done to retain my perceived standing in the small community of Stokesley (as it was fifty years ago).  It seemed to me that the measure of a man (boy) was mainly determined by his bike and to that end, my well worn old screeve (as bikes were then locally known) would need some serious attention. 

The frame was duly stripped and re-painted with Humbrol black enamel.  Cow-horn handlebars and knobbly tyres were purchased from Westbrookes Garage, and then the ultimate accessory – a new back wheel with Sturmey Archer all steel 3 speed ball bearing hub and 28 tooth cog, a special order from Place's bike shop.   Total cost all in, about seven pounds.  At two shillings and thrupence (11P) a day from my milk round (6.30 to 8.00am, 365 days a year) this equated to over two months wages, a big outlay.  Life was hard... you know the rest.     Anyway, all was well for a while.  My re-furbished machine looked pretty good and performed very well on the various circuits around the towns beck-side but my slightly enhanced position in the pecking order was to be short lived.  The local Blacksmiths son (another founder club member) had also been busy re-building his bike and I was given a preview. 

Astonishment quickly turned to envy.  It had front suspension.  Now I know that the mountain bike fraternity generally believe that this development appeared around 25? years ago (no pedants please) but this 'son of a blacksmith' can lay claim to being a clear 20 or so years ahead of the game.  Close scrutiny of the design revealed the following:

The front forks had been turned round.  Telescopic tubes were fabricated from an old bike frame, the cross bar removed then cut in half and neatly slid inside the cut to length down tubes.  The tubes were squashed flat at the fixing ends and valve springs inserted down the larger ones to effectively form a sprung tube.  A ‘U’ shaped bracket had been made to hold the top of the spring tubes.  This was fixed to the top of the forks with a 1/4 inch bolt where the front brake was previously attached.  The scrap frames forks formed the swinging arm which pivoted on the bikes reversed forks and held the wheel and the bottom of spring tubes – Greaves / Dot style.   The front brake was now attached to the swinging arm forks.  Damping would apparently be considered as the next area for development.
In spite of my recent significant outlay, this new cycle technology really couldn't be ignored.  Fortunately, in the early sixties almost every home had at least one old bike frame in the back garden, so I dashed (almost certainly on my back wheel) home to my workshop (the wash house) and got to work with hack saw, hammer and hand drill. 



A couple of days later the bike emerged with a close technical facsimile of the previously described  front suspension, admittedly with some of the finer details omitted.Now for the trial ride.  The first thing I noticed was that the front wheel seemed strangely  disconnected from the handlebars.  The suspension actually worked quite well but went up and down in unison with pedal strokes.   My new found engineering acumen told me that wheelies (not a 1960’s term) would take a little more effort due to the additional weight of the re-constituted bike frame now attached to the front.  Not to be put off, up went the front wheel, then gravity kicked in, the spring tubes parted company and the valve springs fell out and “boinged” down the road.  Pedalling and balancing for a few seconds, I quickly acknowledged defeat and jumped off the back.



  Re-assembly by the roadside was fairly straight forward and off we went again.  The front brake was applied at the road end.  Up went the swinging arm, (now attached via brake blocks to the wheel), and the entire assembly parted company again.  Being approximately half my current weight and a little more agile, I once again landed more or less right side up.  Becoming quite adept  in the process of road side re-assembly, and considering myself on a par with aviation test pilots, undeterred I was  off again in no time.   So carefully avoiding wheelies and braking, how will it perform on some real bumps at speed.  The engineers amongst you should be able to calculate the next critical path, but probably not the outcome.   At the first bump, the  1/4 inch bolt holding the entire front suspension contrivance promptly snapped.  The bottom of the stem tube landed on the knobbly tyre stopping the front of the bike instantly.  The back of the bike (with me still attached) turned somersault as I shot over the handlebars.   Unlike the previous two incidents, this one really hurt.
It took a little while to resolve the teething troubles but they were eventually sorted.  Now armed with a high level of knowledge relating to spring rates and advanced suspension geometry, it was time to focus on the rear.  This was almost entirely my design, plagiarism being limited to the telescopic sprung tubes.  A gudgeon pin formed the pivot for the swinging arm, constructed from yet another pair of front forks (but somewhat modified).  The gudgeon pin was welded with some difficulty to the frame by a puzzled mechanic at Neasham’s Garage.  Similar complex technology as used for the front suspension provided the springing bits.  A Derailleur gear solved the problem of the chain constantly coming off, the cost of this being the only real expenditure for the entire suspension project.


   The bike (now the best part of 3 bikes) weighed quite a bit and the entire contraption now bounced up and down evenly in unison with pedal strokes.   I have a wonderful memory of a group of racing cyclists slowing down to pass me, each one totally transfixed as I nonchalantly laboured in first gear up Seamer Hill, bum out of the saddle, the whole strange affair oscillating happily.  
After a couple of years, girls replaced bikes and I gave the contraption to my then girlfriends brother, (in the hope of some interesting reward – from the girlfriend that is – not the brother).   Looking back, I really can’t believe that anyone could scrap such a wonderful thing.  I wonder where it is now.

Many thanks to good friend and artist Pete Baker for the illustrations

Next serious post about 120 progress - beginning of January






Thursday 13 December 2012

POST 44 - DECEMBER 2012 - HOT AIR REQUIRED

It's a shame that the comments facility on Google blogspot attracts mainly spammers.  Nothing malicious, just some automated system that sends positive anonymous comments to probably millions of blogs simultaneously in the hope that we will be flattered and might reciprocate, thus increasing their viewing numbers.  I can only guess that the motive is financial, linked to some dodgy advertising income.  Deleting this rubbish is time consuming, so comments for the time being are de-activated.  Get a grip Google!

One serious shortcoming in every old car I've ever owned has been the heaters inability to live up to it's name.  I've resolved the problem in my 140 fixed head by fitting a Mazda MX5 Matrix and blower unit.  It works at least 5 times better than the original but I feel could still be improved on.
My requirement for the 120 is in a different league.  I'm not too bothered about de-misting but on cold days the heater will need to send out a constant blast of really hot air to keep me, and in particular my legs (which are invariably cold) toasty warm. 
As the car wasn't fitted with a heater of any kind, my only constraint is to try to make whatever I fit, appear reasonably similar to the optional equipment item. I also want it to work a good deal better than some of the modern after market heaters currently available. 
So, two areas to consider - first is as big a matrix as I can possibly accommodate in the very limited space available and second is a a multi-speed blower, capable of shifting serious amounts of air through the heater matrix. 
There is absolutely no point in having a matrix filled with slow moving warm water, and that I believe, is a major reason why many old car heaters are so poor.  The colder the day, the less heat they appear to produce.  I think (hope) the solution to this is to use an electric booster pump (EBP).

Bosch Heater Pump with PWM control.  Just need to hide
the knob under the dash.
This will work in conjunction with my electric water pump conversion (see post 42).  The heater will have (when required) first call on the hot water supply, with the main water pump, radiator and fan topping up the cooling as and when required.  As with the main water pump, the heater booster pump will have pulse width modulation (PWM) control to set its speed, effectively allowing control of the temperature in the matrix. 

My interpretation of how this will look and work with both
Electric Water Pump (EWP) and Electric Booster Pump (EBP)
shown.  The graph relates to the EWP control only.
The matrix needs to be enclosed in a box mounted on the engine side of the bulkhead with it's output passing to the other side, the passenger compartment just above the gearbox cover, more or less as the original heater.  The largest unit I can find that will fit comes from Car Builder Solutions http://www.nfauto.co.uk/ and measures 8" x 5" x 2" high.  It also has its pipes running in the right direction for what I think will make for a neat installation.

£48.00 Heater Matrix from Car Builder Solutions
The worst part of the job is tackled first.  Not that it's difficult, but I hate cutting holes regardless of necessity.  It makes me feel a little better to know that this one is in the same place as the original would have been if the optional heater had been fitted, just a slightly different shape.


Hole for Heater Matrix output cut in bulkhead
Next I need to work out the design of the enclosure.  Air will be pushed into the top of the matrix from a blower which will be mounted under the passenger wing in a 140 style battery box.  The hot air will come out of the heater matrix into the cabin from two 3" vents, each with rocking and rotating vanes to direct the flow.  It may even be possible to fit an original heater cover over these (if I can find one)


Draw it first, half the fun, if like me you enjoy that sort of thing,
but still leaves some elements of 'making it up as you go along'

The enclosure is made from 1.5mm Aluminium sheet, cut, bent and riveted together.  Isopon sealed the joints airtight and high temperature silicone fixed the matrix in place and ensured no leakage between the input and output chambers. On completion, to check for leakage, I submerged it in water to see if any air bubbles emerged - none.

Inside of enclosure with chamber divider Araldited in place
Years ago I borrowed and used some cracking good and very clever 'sprung' rivets to temporarily hold sheets of aluminium together, mainly to allow accurate drilling of additional holes, but also to allow easy dismantling and de-burring before final assembly.  I lent the kit to someone and you can guess the rest.  I saw something almost identical advertised (again Car Builder Solutions) but under the brand name of 'Cleko'.  I bought the base kit, insertion tool and 10 1/8 inch Clekos and they were once again indispensable.

Side of heater matrix enclosure temporarily 'cleko'd' together.
Happy with the matrix enclosure, I give it a roughing up in my blast cabinet to ensure good paint adhesion, before applying a few coats of satin black to match the rest of the engine compartment.

Finished enclosure - Air inlet sits below bulkhead and has 4Nr
3/16 UNF inserts araldited on to allow fixing of 63mm flange
for flexible pipe from blower.

Water in / out side of enclosure

Finally in place on the bulkhead.  Just needs a couple of Smiths
Heater labels to fool all but the most astute XK aficionados.
The rivets will hopefully be less obvious without the camera flash.
The second part of the installation, the blower, to be ensconced under the passenger wing will be completed in February and finally, the booster pump and plumbing after the engine is re-installed, probably in April. 

Whilst I optimistically hope this will produce all the heat I could ever ask for, I am aware that it is at this stage mainly theoretical - The proof of the pudding etc.
My glass remains as ever, more than half full!!!

Rear wings and doors - Trial fit
Having secured the body to the chassis and carefully and continually checked the door gap measurement between two datum points, it's time to trial fit the rear wings and doors, just to ensure nothing major has occurred during the process. 
I also have the wing beading made up by the trim man so this is also trial fitted. Alex and Niel from Auto-Bodycraft arrive 7.00am prompt and spend a couple of hours hanging the doors and setting the gaps back up. Door and wing fit turns out to be as good as I have seen anywhere. The beading still needs a little 'tweaking'.

Doors will be taken off again to prevent damage, but I now
know for certain that the gaps and fit are excellent. 
Thanks to Alex and Niel at Auto-Bodycraft
Miscellany
Visitors invariably comment on the general tidiness of the workshop, but in reality they don't see the real mess it gets into on occasions.  I usually call a halt when I can't find things anymore.

Halfway through the heater enclosure job.  Picture proves that
it's not quite as organised as it sometimes seems.
Next Post Early January 2013


 

Sunday 2 December 2012

POST 43 - DECEMBER 2012 - ODDS & ENDS

A bit of a mixture of stuff going on at just now.  Even allowing for the expulsion of all none XK120 related bits from the workshop it's bursting at the seems.  I suppose that this is the point in time when maximum space is required, just before some of the more space consuming parts are re-fitted. 



Every shelf and horizontal surface now occupied - can only get better
I seem to have spent a good deal of time ensuring that the body is correctly fitted back on the chassis but with 5mm rubber replacing the water absorbing and rust inducing felt originally used.  This will also be used between the chassis and the floor boards when I eventually get round to fitting them.

I've finally decided on the Coach Trimmer or should I say after I was 'interviewed' he considered me a suitable client.  John Richardson of Shildon comes very highly recommended by several friends and acquaintances.  He previously worked for David Royle at Barnard Castle, a restoration company with a huge reputation, and used by London's Rolls and Bentley specialists.  Alas Royles went out of business a few years back mainly I understand through some rather large unpaid bills.  Anyway, John decided to set up on his own but restricts his activities to one job at a time and works by himself.  On my first visit, he was busy making a pair of new but old looking seats for a fabulous Delahay race car which almost filled his workshop.  Certainly no doubts about his trimming credentials then.  
My car is booked in for the full works, upholstery, door cappings, carpets, hood, side screens and tonneau and will be away for two to three weeks in March next year, but in the meantime I can send John a few parts to be getting on with.
Having finally decided on Old Red and Biscuit, my amateur effort of trimming the dash in red leather back in spring 2011 now needs to be re-done in biscuit with red edging. 

All to be re-done in biscuit with old red edging
I've decided to change the seat backs to bucket style and order a set of seat frames from Aldridge, trimming company.  The bases are longer and a little thinner than the originals, but very sturdy and well made and will still hinge forward to access the area behind the seats.  This also means that I can increase the height of the central arm rest by a couple of inches to incorporate a storage area.  In all other respects it will look identical to the original. 

New central arm rest, now with storage and ICE controller
The plan was to install a Pure Highway 300i DAB Radio and iPod interface / controller under the hinged lid. Only problem is that they seem to be sold only by Halfords who don't have any, so may have to re-think this, but in any event I don't want any ICE kit on show.
Pure Highway 300i controller will sit nicely
in arm rest storage and also control iPod.
Just need to find one!
With the exception of front disc brakes which I can't do anything about, I really don't want any of the many upgrades I've planned to be seen and this includes hiding away a secondary wiring loom for the ancillary equipment.  To this end, an additional four fuses are required, which need to be accessible but out of site.  The RF95 Voltage regulator is really now only required as a terminal block as its innards have been made redundant by the fitting of an alternator.  The space vacated by it's coils and relays makes an ideal home for a neat little fuse assembly.


Four way fuse box now lives in RF95 Voltage Controller

Side View - looks like it's always been there and will disappear
entirely once the cover is in place.
One job that I intended to do as soon as I got the body back onto the chassis was to check that the door gaps were still as perfect as they were at the body shop when mounted on the jig.  Ideally I need the rear wings back on before this can be done properly, but I need to fit the spring gaiters and locate the correct wing beading before I fit the wings.  The gaiters were sourced some time ago from Wefco and I actually spoke at length to the lady who was going to sew them together which was rather nice.  They looked pretty good before fitting but look superb once sewn up on the springs.


Beautifully made rear spring gaiters by Wefco

Fit on original springs is perfect.  
I understand that on early steel 120's, the beading between the rear wing and body was made up from rexine over paper cord then painted body colour.  I have managed to source some exterior quality Vinyl (normally used for hoods) which looks similar to rexine and is almost an exact colour match and this will be used to make up the beading.
 
My recent visit to the Classic Car Show at the NEC started very well.  The entrance to the exhibition was dominated by a beautiful 120 Roadster on a pedestal, who's first owner was Clark Gable.  This car has been restored at very considerable cost by JD Classics and went on win best in class at this years Pebble Beach Concours.  With such a prestigious win, I would expect it to be technically correct in every tiny detail, meriting around thirty photographs for future reference.


One off special colour by the factory - became known as
Gable Gray.    Note rear wing piping in body colour.
 Pity they wouldn't let me open the bonnet and boot.  I was reliably informed by it's temporary custodian / security guard that this was not possible due it's value of £3.4 million!  With Chassis No 670003 it's certainly worth more than a later aluminium car at say £250K but how much more will the Gable connection influence it's value?

Clark Gables 67003 - Value £3.4 Million? - Unlikely but who knows
Miscellany
The stream that runs thirty meters from my front door has a normal level of around three meters below my damp proof course.  Up to the 27th of November it had rained almost continually for four days and I must say I was starting to become a little concerned when I could see the level rising by the hour until it was almost over the top.  This is in spite of a very expensive flood relief scheme built in 1979.  A little research revealed that we are still in a 'zone 3' area which effectively means we can expect to be flooded once every one hundred years or so.  With thirty odd years gone, the odds are shortening!  Fortunately the rain stopped a and within a few hours it was back to normal.



Next Post mid December