Ex-Racer Spitfire Mk1 Rebuild

[TimBancroft]

Pete,

That could be a Shacktune flywheel (although I am not sure if he is making flywheels for 4 pots)???? James Shackford is Shacktune, who is a regular RBRR man, could be helpful, contact me for details.

[PeteStupps]

Thanks Tim, I'll keep that in mind when I get to my gearbox overhaul. Which will now be before the postponed RBRR. Overdrive will make it quite a different experience I reckon!

[TimBancroft]

Most certainly, lot more relaxing and less stressful.

[John I]

That looks suspiciously like a Mark Field  "Jigsaw Racing" flywheel. They use to sell on eBay under the name lemans-r and I think there is still some around.

[Escadrille Ecosse]

26 minutes ago, John I said:

That looks suspiciously like a Mark Field  "Jigsaw Racing" flywheel. They use to sell on eBay under the name lemans-r and I think there is still some around.

That's exactly what it is John. Came from Mark

[John I]

2 minutes ago, Escadrille Ecosse said:

That's exactly what it is John. Came from Mark

Nice looking piece of steel.

[Escadrille Ecosse]

Very nicely made. Finish close up is excellent. Fit was first class as well.

Just need to see how it goes!

[John I]

4 minutes ago, Escadrille Ecosse said:

Very nicely made. Finish close up is excellent. Fit was first class as well.

Just need to see how it goes!

Hopefully that is just around the corner

[TimBancroft]

James Shackford gets his flywheels made in association with Alistair Pugh, who runs A2P2, the reverse engineering company. Alistair also used to race Mark Field's Le Mans Spit rep ast CLM...connection? 

EE's flywheel looks very similar to the one in my GT6 mk2, as supplied by James.

[TimBancroft]

http://www.a2p2.co.uk/index.php?idPage=17

[Escadrille Ecosse]

Some nice stuff there.

I used the 3D scanning when I was working for making full size CAD models of the refrigerated LPG storage facility at Grangemouth so we could assess movement of the storage tanks and pipework, work out inspection routines, simplify design of repairs and modifications and stuff like that.

It's a superb technique even on the scale of a half mile long site with tanks 100ft high you can get millimetre accuracy (and yes I realise the mixing of units there!). Remarkably quick too.

[Escadrille Ecosse]

Time for an update on progress on the Spitfire.

Work on the door skins has been proceeding but proved to be a rather tedious job. Basically they fitted only inasmuch as they kind of filled most of the hole used to get in and out of the car.

A lot of the problem here is that the doors I took the original moulds from were not in that great a condition and I'm pretty sure they had been reskinned at some point before I got them. Combine that with the rebuilt tub and there's a fair bit of fettling to do. I don't remember it being this hard when I built the car originally but then I was more interested in the least possible weight rather than perfect panel gaps.

So anyway, after gluing the GRP panel on to the eggbox frame with tigerseal it did at least get rid of the twist and got the crease line matched up front and back. Then came endless trimming and adding around the edges to get a roughly even gap. In the end I went for about 3mm at the back of the door, 8mm at the front and 5mm along the bottom.

The top edge of the door was the most awkward as it was about 2mm low at the back of the door and almost 4mm at the front. And in addition the angle of the extension past the scuttle top was wrong. So I clamped a batten along the top of the door at the correct height and used that as the edge to work to with the filler.

Took forever. However with the skin fixed to the framing I could at least take it off the car to work on the bench which was a lot easier than trying to do it in situ.

Part way through the job. The bulk of the filling is done and there's a primer guide coat on there.

The finished pattern. As the final part will be painted a glossy surface isn't necessary cosmetically but it makes separating from the mould a whole lot easier. It is also critical that any filler is sealed with a coat of paint as it has a slightly porous surface that will defeat even the best mould release system.

Should be shiny enough

That's U-Pol Power-Can grey etch primer on there. Have to say it is probably the best rattle can primer I have found to date. Highly recommended.

Mould flanges applied along with the fillet of wax all round the pattern.

I have been pondering how to mould the return flange along the top edge of the doorskin. The window seal fits to this but the main purpose is to reinforce the free edge of the doorskin. On my orginal GRP moulds this return was formed as part of the mould. However it is a very tight return angle and not ideal although with a bit of care it is possible to hand lay up into this area.

However this sort of very sharp angle is not recommended, especially when using carbon fibre reinforcement and I was especially doubtful about my ability to form this bit with the vacuum bag/resin infusion process I'll be using.

So my solution is to make this section in two steps using a two part mould. The main mould (here) and a second section to form the return. Then once the moulds are finished I can make the main skin using resin infusion and once that is cured but still in the mould, bolt on the flange mould and form that with a hand layup. I will probably also make up a shaped former to clamp the reinforcement into the return while it cures and ensure there are no voids. You can just see the three alignment pips stuck on the mould flange along the top edge of the door in the photo.

I'll be laminating the mould over the weekend as I need two clear days for things to cure along the way.

Edited August 19, 2020 by Escadrille Ecosse
grammar

[Escadrille Ecosse]

A couple of other things on the go when I have got too bored sanding filler.

I have have tidied up my bunnyvac-3000 vacuum system in the garage. The separator drums are off the floor on a shelf along with the dehumidifier and I have plumbed in three extract connections each with a slide valve. Means I can run a hoover and a hose to the sanding block at the same time and adjust the relative sook accordingly.

I have to say that the vac extract sanding blocks are absolutely superb at keeping the mess down when dry sanding filler. Takes velcro backed ceramic mesh sanding sheets. Not cheap but don't clog and last far longer than traditional paper.

The best bit though is that I have put the connection for the industrial workshop vac outside so I can actually hear myself think when it's running. Apparently though the family can hear it from inside the house, even with all the doors and windows shut!

[Escadrille Ecosse]

My plan is to fit EFI to the Spitfire to replace the Webers and mechanical distributor ignition.

Not sure what system I will be going with ultimately although I have some basic thoughts, foremost amongst it being that I want it to be 'relatively' simple plug and play rather than another development project.

In the meantime and having read what I can here and elsewhere and spoken to a few people, in particular Darren Groves, I am starting with the various sensors. First up is the lambda sensor port in the exhaust which I did while I was sorting the damage to the chassis at the wishbone mount.

There isn't a lot of space in there and having read what others have done I went for locating it here. Angled down as specified but pointing under the gearbox rather than between it and the chassis rail as there isn't a lot of space there and accessing it from this side is easier without going into the car. Especially with regards to the cable.

Right now I haven't made a final decision on whether or not to run the system on closed or open loop as the actual sensor and interface to the ECU seem to be one of the most problematic elements of closed loop systems. And in any case the car has run open loop for pretty much it's entire 57 year life!

In which case it will only be used when setting up the system on the rolling road and 'someone else's problem'.

[BiTurbo228]

First off great work wit hthe door form and I'm as amazed at the quality of the spray as you are! We've got a couple of cans of the old-style u-pol weld-through primer that are brilliant. Not particularly weld-thru (are any of them?), but 

Also I'm dead jealous of the vacuum sanding setup. Some of my clothes are still blue from the dust on the Spit!

Be interesting to see the EFI conversion. Each one tends to be slightly different in application so useful to pick and choose bits you like

[Escadrille Ecosse]

Thank you. Yes I decided that I could no longer cope with the dust in the garage and went a bit nuclear.

Aside from anything else I thought the saving on bags for the Vax would be huge. The dust is so fine that they clog up after a couple of hours of use while still almost empty and then anything you suck up just gets recycled straight out the vent!

[Nick Jones]

5 hours ago, Escadrille Ecosse said:

Right now I haven't made a final decision on whether or not to run the system on closed or open loop as the actual sensor and interface to the ECU seem to be one of the most problematic elements of closed loop systems.

Not really.  Mine has mostly worked as intended.  Just don't give it too much authority.

No system is truly plug and play, regardless of cost.  For a 4 pot, Microsquirt takes a bit of beating.  I hesitate to recommend Speeduino, in spite of the excellent cost/features ratio, but maybe we were just unlucky.  Most of the reliability is in the wiring loom, connectors and earthing strategy. Closed loop idle control is a bitch to get right but I've managed without that for 16 years.

Smart move positioning the sensor where you can extract it without dismantling half the car......  I have to take the whole damn exhaust off to get at mine, though to be fair the fat-boy gearbox severely limits the options.

Love the vacuum extractor system........ and impressed with your composite skills.  Not something I've mastered.

Agree on the Upol power can range.  Works well.

[Escadrille Ecosse]

Cheers Nick. Will be interesting when I get to that stage and have to make the commitment!

Useful comment about the lambda sensor. Your point about the wiring/connectors is well taken and I will pay great heed.

Our old Seat Ibiza gradually ground to a halt as various things just stopped working apparently overnight which I put down to connector problems as changing components just turned into a way of giving disposable income away.

The radio was first although the trick there was to put a cassette tape in at which point the radio would burst into life. The random limp mode was mainly just annoying as it would usually reset at the first attempt. Although when turning on and off the ignition to reset you had to be careful not to engage the steering lock!

The final straw was when we could no longer open either door from the inside and only the passenger side window would go up and down which made actually getting out of the thing just too difficult.

[Nick Jones]

Sounds like entirely typical VAG-of-the-2000s behaviour. Probably less reliable than contemporary French and Italian offerings and definitely inferior to Kia, Hyundai and the Japanese.

The ignition switch is a very common failure point that causes radio problems,  failed starter symptoms and random failure to proceed. Cheap easy fix though. Also the use of very light wires causes starting faults, charging faults, plus check engine lights and running issues due to flakey sensor connections.

On later cars you get assorted major engine failures added to the mix. Snapped oil pump drives, failed piston rings, failed timing chains.......

We’ve had very good service from older VAG products but I’m very wary of the more recent ones.

[Escadrille Ecosse]

Gelcoat on the pattern for the outside mould. Allow to cure to tacky surface overnight and laminate tomorrow.

Meanwhile, a few weeks ago I fitted a trigger wheel for the crank position sensor. I wanted it to be as unobtrusive as possible so I went for a 3" 36T wheel to sit in behind the pulley

Got a small step machined on the back of the pulley to locate the wheel

Trigger wheel could then be rotated into the correct position once the sensor position was finalised and welded into place.

Sensor bracket made from a bit of 50x50x3 mm box section to take the Ford Focus position sensor.

Spacing to the trigger wheel determined by washers

Whole thing pretty much out of sight and harms way and when the pulley and trigger wheel are painted black almost unnoticeable. Especially once the radiator is in place. The angle of the picture makes it look like the sensor is very close to the rack but there is actually about 1" vertical clearance between the two.

When I had the timing cover off I noticed that the sharp corner on the tensioner was wearing a groove in the side of the cover.

So I welded a small wear plate and guide to the inside of the cover

And rounded off the sharp corners on the replacement tensioner - old vs new

 

[Nick Jones]

Neat trigger wheel install 

I’m watching the composite stuff with interest - it’s witchcraft to me......

[Escadrille Ecosse]

[Escadrille Ecosse]

Finished the layup of the main part yesterday. Gelcoat cured but the surface still slightly tacky.

Apply some resin onto the gelcoat. Then a layer of surfacing tissue and one layer of 300 g/m2 chopped strand mat (CSM) as the initial coupling coat onto the gelcoat. Well wetted with resin and allowed to cure for an hour.

Wetting out the CSM with resin which breaks down the binder holding the strands of glass together. As it wets you can then work the mat into any corners to make sure there are no voids. You can see this where the shape of the skin meets the flange. The lower edge of the door is work in progress. Compare to the rear edge nearest the camera. Having said that the mat doesn't cope well with very sharp corners. The coupling coat it the most important place for this to ensure no voids between the brittle gelcoat and the structural layers.

You can see this on the picture with the coremat where there is a small void round the edge. Doesn't matter much there, it is well away from the gelcoat. If I was using coremat in a part I would taper the edges to eliminate voids. But doing that on a 'fabric' is a pain in the backside so reserved for critical applications.

Then another two layers of CSM, a later of 1mm thick coremat fabric for bulk and then a final layer of CSM.

Not quite enough on the roll to cut all four layers in one piece so number three needed a wee bit adding at the end. Not an issue just make sure there's an overlap.

The pieces were cut square but roughly to size beforehand then given another trim as they are applied. Makes it easier to work with, limits waste of resin into the bits sticking out and avoids the possibility of lift in the layers at the very edge of the layup where stiff un-resined mat meets the resined stuff. Makes final trimming of the cured material a lot simpler and less prickly too.

Needs to cure on the pattern for another few days to keep it well supported but I can make the other mould section for the flange along the top while that's going on. So I stripped off the corex board to see.

The wee plastic wedges are great for separating the parts. Corex is easy but getting a part out of the mould can be a real b#####d until you break the initial suction and the wedges are brilliant for that.

I used self adhesive silicone rubber buttons of the type you use as 'feet' to form the locating pins for the two parts of the mould.

I'll leave things until tomorrow at least before prepping for the other part of the mould.

Edited August 23, 2020 by Escadrille Ecosse
additional detail

[BiTurbo228]

Yep, complete witchcraft.

The only useful tip I know about fibreglassing is that it doesn't stick to parcel tape so you can mae one-off patterns out of cardboard/foam, coat it all in parcel tape and then glass over the top.

Trigger wheel install looks great too

[Escadrille Ecosse]

Yes. Handy stuff parcel tape