Slow Monster rebuild

350TSS · 15-10-2019, 07:28 PM

Garage clearance once more took a back seat over the past couple of days, first my son’s car failed MOT (rear tyre gone oval and a lack of brake force on NS rear wheel which turned out to be one of the two actuating pistons seized solid). I can see this job being a long haul as the rubber flexible brake pipes are quite hard and probably will not appreciate being clamped which means that I will have to put a rubber glove under the master cylinder cap and hope I do not lose all the fluid when I try to get the cylinder off. What was worse was that every time I got underneath the damn thing it started to tip it down. I bloody hate working on cars. Anyway, a new wheel cylinder is ordered and whilst I wait the attachment bolts, the brake pipe and bleed nipple get a good daily dosing of penetrating oil in the hope that the flange nut comes out without strangling the brake pipe itself.

Today the last pour of ethanol resistant resin was made into the tank. I will leave this for about a week to cure off properly before I test whether or not it is petrol tight. I think I would like to make some form of pressure tester so I can blow compressed air into the tank to see if it is likely to leak but I cannot work out a way of sealing the filler cap hole. Compressed air would be preferable to petrol as if there is a leak the petrol will contaminate the site of the leak and make sealing it with resin more difficult and I cannot really get my head around filling it with water as that is just anathema (also petrol is thinner than water and will penetrate where water won’t).

Today rather than clearing the garage, I made the clamps for the ambla seat upholstery out of 3mm polypropylene. I cut the polypropylene with a jig saw as a Stanley knife just will not cut 3mm. I had the usual problem of the jigsaw blade getting hot and the polypropylene welding itself together behind the saw blade. This means you have to cut it out about 3 times and with all the white semi molten plastic you never really manage to follow the line that you prescribed to be cut out. Thus you end up with a lot of remedial filing/ linishing to get a straight edge. It came out reasonably OK in the end though. I do wish I had chosen 4mm csk screws as the basis for the clamping “studs” as I spent most of the day picking up errant 3mm nuts that my banana fingers just cannot grip/manipulate.

Unfortunately I cannot complete this just yet as I need some longer countersunk 3mm cap screws for where the CF is especially thick and where the strap fits over the hump although I did make a start on cutting out the 6mm base layer of closed cell rubber foam. I still have no idea how to secure the ambla at the rear end of the seat.

Luddite · 16-10-2019, 12:51 AM

Great work as usual, Richard. It must be very satisfying to see things finally taking shape.

Quote:

Originally Posted by 350TSS

I think I would like to make some form of pressure tester so I can blow compressed air into the tank to see if it is likely to leak but I cannot work out a way of sealing the filler cap hole.

Have you considered using smoke to check for leaks? Some of the larger car dealerships have 'Smoke Wizard' units for leak detection. These pump smoke at low pressure into a sealed system and any leaks are obvious from the escape of the smoke. I'm sure if you can find a dealer with this equipment they'd be able to check your tank for you.

https://garagewire.co.uk/news/smoke-...k-diagnostics/

Would a large rubber bung (or even cork) cut to size and tapered be good enough to seal the fuel filler hole? Or a thick rubber balloon inflated into the neck perhaps?

Mr Gazza · 16-10-2019, 04:35 PM

Wine or beer brewing kits have big rubber bungs and you can get them from suppliers of kits and home brewing equipment.

I've just read how they used beer brewing bungs on the Black Buck Vulcans to seal the pressurised bulkheads where they had run extra cables through from pylon mounted radar jammers, borrowed from Tornadoes... They had to build the pylons too, but that's another story,,,What a brilliant story though... Read "Vulcan 607"

Just put a little air in it and plunge it into the bath, like a bicycle inner tube..

Another good leak tester is clutch and brake cleaner.

16-10-2019, 04:35 PM	#3
Mr Gazza Lord of the Rings Join Date: May 2013 Location: Norwich Bike: M900sie Posts: 5,831	Wine or beer brewing kits have big rubber bungs and you can get them from suppliers of kits and home brewing equipment. I've just read how they used beer brewing bungs on the Black Buck Vulcans to seal the pressurised bulkheads where they had run extra cables through from pylon mounted radar jammers, borrowed from Tornadoes... They had to build the pylons too, but that's another story,,,What a brilliant story though... Read "Vulcan 607" Just put a little air in it and plunge it into the bath, like a bicycle inner tube.. Another good leak tester is clutch and brake cleaner. __________________

15-10-2019, 07:28 PM	#1
350TSS Too much time on my hands member Join Date: Jan 2013 Location: Shipbourne Bike: M900 Posts: 1,419	Garage clearance once more took a back seat over the past couple of days, first my son’s car failed MOT (rear tyre gone oval and a lack of brake force on NS rear wheel which turned out to be one of the two actuating pistons seized solid). I can see this job being a long haul as the rubber flexible brake pipes are quite hard and probably will not appreciate being clamped which means that I will have to put a rubber glove under the master cylinder cap and hope I do not lose all the fluid when I try to get the cylinder off. What was worse was that every time I got underneath the damn thing it started to tip it down. I bloody hate working on cars. Anyway, a new wheel cylinder is ordered and whilst I wait the attachment bolts, the brake pipe and bleed nipple get a good daily dosing of penetrating oil in the hope that the flange nut comes out without strangling the brake pipe itself. Today the last pour of ethanol resistant resin was made into the tank. I will leave this for about a week to cure off properly before I test whether or not it is petrol tight. I think I would like to make some form of pressure tester so I can blow compressed air into the tank to see if it is likely to leak but I cannot work out a way of sealing the filler cap hole. Compressed air would be preferable to petrol as if there is a leak the petrol will contaminate the site of the leak and make sealing it with resin more difficult and I cannot really get my head around filling it with water as that is just anathema (also petrol is thinner than water and will penetrate where water won’t). Today rather than clearing the garage, I made the clamps for the ambla seat upholstery out of 3mm polypropylene. I cut the polypropylene with a jig saw as a Stanley knife just will not cut 3mm. I had the usual problem of the jigsaw blade getting hot and the polypropylene welding itself together behind the saw blade. This means you have to cut it out about 3 times and with all the white semi molten plastic you never really manage to follow the line that you prescribed to be cut out. Thus you end up with a lot of remedial filing/ linishing to get a straight edge. It came out reasonably OK in the end though. I do wish I had chosen 4mm csk screws as the basis for the clamping “studs” as I spent most of the day picking up errant 3mm nuts that my banana fingers just cannot grip/manipulate. Unfortunately I cannot complete this just yet as I need some longer countersunk 3mm cap screws for where the CF is especially thick and where the strap fits over the hump although I did make a start on cutting out the 6mm base layer of closed cell rubber foam. I still have no idea how to secure the ambla at the rear end of the seat.