Driving a 1954 Austin-Healey 100/4 from Peking to Paris in the June 2019 ERA Rally.

Saturday, 22 September 2018

0067 The roll bar takes shape

23rd September 2018
Roll bar, seats, and even more red dust !

253 days to go !!

Roll bar almost complete
Ever since we got back from Alice Springs 3 weeks ago Gidget has been
And seat almost there too
up at J&H Restorations to design and fabricate a roll bar. All the original design phase using plastic pipes, and options for changing the soft top mounting method were detailed in my last post - As were the initial plans to use some MGF Trophy 160 seats in place of the retro seats we have currently.  The time required to design one-off items like this is always a lot longer than can ever be imagined if you have never been involved in car restoration, but I am pleased to confirm that we are nearly there !  We almost have a roll bar and we almost have seats !!

Checking mock up bar for height
First task was to do a "fitting", using the new seats, to check our head clearance to both the roof and also the proposed roll bar height - No good having the roll bar 4 inches lower than our heads !!  The seat in the car still had runners fitted, but this is referred to later on.   The result was that everything was good, and Brett could therefore proceed with making up the bar out of 40 x 3 mm steel tube.  We also looked at shaping the top of the roll bar to match the shape of the rearmost (of 2) roof stays, so that we could then remove the rear stay, simplifying the whole set up for the roof.  We also looked at the bend in the front roof stay which was giving the roof its lop sided appearance when raised.

While I left Brett to work on the steel side, I went looking for cargo nets.  One of the big issues we
Lots of options for cargo nets
have is securing all the stuff that will be carried in the boot - During COT we found that our existing method of strapping down the multiple plastic boxes just didn't work - Any bumpy road soon had boxes bouncing all over the boot, and ending up damaged.   So our new plan is to use more small soft canvas bags (because they squish down to a smaller size when 1/2 empty), and to use a cargo net (as used on the back of Utes) to more securely keep everything in place.  As usual, an initial search raised more questions than answers, but I am leaning towards a much finer mesh unit, and then making sure it can be not only tightened down fully to hold the cargo in place, but also be quickly and easily fastened and unfastened when access is required.

Seat without its cover
Next it was off to the seat uphosterer - Steve at ZZ Trimming.  The MGF seats are serviceable but well used, but as we plan to put a washable seat cover over them, looks are unimportant.  However one of the seats was slightly ripped in the base, as was shown in the pics accompanying post
0065, so I took this off to Steve to address.  Additionally, during the trial
Seat foam to remove on back
fit of the other (unripped) seat in the car, I noted that the back of the back of the seat has plenty of foam in there which is unimportant, so to enable the seat to be mounted as far back as possible, we planned to remove some of this excess padding.   A few days later the torn section was fixed, with a new leather strip inserted to make it stronger, and a
Repaired seat base
section of padding on the back had been removed, giving us another inch or two of movement.  Not a difficult task.  A good coating of black shoe polish brought the leather up nicely removing all the old scuff marks - They could almost be new seats !!

Cleaning seat belts
Bottled red dirt for Ashton !
Meanwhile back at home I was still trying to clean red dust out of everything !  The seat belts were particularly troublesome, requiring work with a wet toothbrush in order to get the red out of the fine webbing !   And even then, when they dried, they still had a red tinge, and needed a second treatment !  I found so much red dirt I was even able to bottle some and label it appropriately in order to send to to Ashton so he can have some good memories of the Adventure in Alice !

Main bar & supports made up
By this time, Brett had received the bent tubing back from the tube bender for the main part of the roll bar, and had fabricated the supports that would bolt onto the inside of the rear wheel arches, supporting the main roll bar mounts.  The ones shown in the photos will be trimmed down once everything is
Worn roof clip
dummied up.  The soft top had also been looked at, and the hooks which locate the front bar across the windscreen top were found to be seriously worn and mishapen, which was one reason the front didn't seal properly.   A seccond reason was found - the thick rubber strip across the windscreen was about 1
Where rubber seal removed
cm too thick - Obviously a previous effort to seal it had been to just put a thicker piece of foam in there.  However by doing this, the small lip which was supposed to fit over the edge of the windscreen and prevent water entry had been raised, thus making the seal even less effective !   By removing the thick foam, the outside lip came back into play, and by making up some new locating hooks, the windscreen now sealed tight !   Brett also straightened the bent roof support bar so the roof now not only sat level, but we also had an extra inch of so of head clearance inside !

Roof fitted over roll bar
On my next trip up to Yatala I emptied the fuel out of the upper reserve tank into the main unit, then removed the upper tank in order to make welding in there a little safer.  As expected, we found lots of red dust in there under the tank !!   Having tacked the main roll bar in place, we then ground off the pins holding the rear roof brace in place, and fitted up the roof using the roll bar in place of the roof stay, and it worked well.  There is a slight section on the rear corners where the fabric is not tight, but this will be filled by the rear braces when they are fitted - Otherwise the roof fitted well,  and a trial fitting of me inside showed we had slightly more headroom.

Brett lining up rear braces
Then it was on to working out the positioning of the rear braces and detailing where they should go through the shroud, and this was done by drilling just a small hole in the anticipated location and then using a plumb bob to make sure it matched up to the panel below the shroud.  Minor adjustments could then be made
Placing for rear brace tube in boot
to ensure it was in the right spot.  It was at this point that Brett made an additional suggestion - If he took an additional brace tube off the very top of the rear brace immediately below where it came through the shroud, and ran this tube right back to the rear chassis extension bar at the back of the boot, it would provide considerable extra rigidity and strength without taking up too much boot space.  In addition, it would provide an excellent firm point for our straps to hold the cargo net in place.  A quick phone call to Ashton in Sydney to run this past him, and we all agreed it was an excellent idea, and should be implemented.

Perspex screen on bar
I had paid a visit to friend John Crighton who is also on the P2P in his MGBGT, and mentioned the fact that our roll bar may enable us to fit a plastic rear "wind deflector" to minimise wind and dust entry from the rear.  John just happened to have one that he used to use on his previous MGB convertible, and he has give it to us to try on Gidget - It will be interesting to see if it works.
Wheel arch mounts
I took it up to Brett and the main roll bar was now finished with the diagonals in place - Its a solid piece of work !   With the mounts now in place on the wheel arches, we were able to fit the bar and see how straightforward it is to fit and remove.  Now it is just a question of fitting the bases on the inside of the rear shroud and, once everything fits, cleaning it up and getting the whole thing painted.  It is certainly going to provide us with the required protection.

New seat (L) vs current
It was back to the seats, and removing the runners. Due to the short
driving position in the Healey, and the fact that we are both 6 footers, we plan to mount the seats directly to the floor without runners as this will give us some extra clearance inside - But I wasn't ready for how much extra room it would provide.   Getting the runners off was a nightmare - I cannot believe how many welds and rivets held them in place to the main frame of the seat - And most of them were really hard to get the angle grinder in to !!  Eventually
New seat height
Original seat height
they were off, and when I measured them up against the previous seats,  the height at the front of the seat was 150 mm compared to 270 mm of the previous seats.  We may need to raise the front of the seats up to provide some additional thigh support, but the rear of the seat will remain low, and thus we should have some 10 cms of additional head clearance.  This should enable us to look through the windscreen instead of at the chrome strip on the top !   Next job is to make up some simple brackets to enable us to bolt the seats to the floor and fit hinges at the front in order to enable us to access both the battery and a storage box located behind the seats.

Rear brace mounts in boot
So at the end of the week, the two major changes are looking good, and will hopefully be completed in the next week or so and we can get on with the many smaller items that remain on the to-do list.

Rest of the photos are here :-  https://photos.app.goo.gl/rX9A59WkTnvTbxLm7


  1. How are you going to know the ideal seat position for Ashton, and what if you are called upon to drive, you being taller than Ashton?

  2. a) We are appoximately the same height
    b) The width of the seats and the width of the available space makes sliding movement limited anyway.
    c) Unless you are under 5 ft tall, or have had a double leg or arm amputation, there is only one feasible position for the seat, and that is as far back as possible.
    We are talking about seriously limited space in these old cabins, Eddie !! The straight arm position is impossible !


Ashton & Giles welcome any visitors, support, and comments as we prepare for our Adventure !