Section XII Internal Sheet Metal Work

These note should be used in conjunction with the Video's

Before we can go much further the next logical sequence is to fit the internal sheet metal panels. These comprise (a) Seat Back Panel. (b) Tunnel sides - 4 items (c) 2 Footwell ends) 4) 2 Firewall panels and a Battery plate.(d) Tunnel top - 3 items. A total of 14 panels if we include the Dashboard which can be left until later.

Some of the panels are miles out and it may be necessary to make new panels that fit perfectly. This applies particularly to the firewall panels and the drivers footwell panel. Make a card template that fits and modify or remake to suit. Drilling holes for the Pop rivets in situ, all dead in line and to correct pitch, with not much space and the sheet already folded is not easy. It is far better to drill the panels "in the flat " before folding using a simple drill jig. Once the panels are in position, the second set of holes can be spotted through with perfect accuracy. Use 3mm pops at 1" centers. I also used 5mm pops for the seat back panel top and the first and last end rivets in any run. Ideally the burrs should be removed from ALL holes but this is not always 100% possible. The Cobalt drills have proved superb, so far I have drilled over 600 holes in the Stainless with one drill, and it has NOT been re-sharpened. See J+L in the Floorpan section.

Talking to builders at various car shows would indicate that the sheet metal work gives a lot of problems to some, and none to others. This would suggest that either skills vary or the kit does. The truth probably lies somewhere in the middle. Panels that do not fit, stainless steel that is hard to fold, Chassis's out of line, Panel holes in the wrong place, the list goes on. Some of the panel cut outs are miles out, the cut outs for the chassis side rails in the passenger firewall for example.

Following the advice in the Video, loose fit the panels using a couple of Self tappers or an Alloy pop rivet. Alloy pops can be easily drilled out and stainless steel pops fitted later. When fitting the Internal Panels make sure the Floor Pan is FLAT. Any bow at this stage will be riveted in. Support underneath with a large sheet of chipboard and a couple of jacks if required, at least until the tunnel sides are riveted on. Most of the panels interact with each other, for example the front tunnel sides must be at the same height otherwise the top will slope.

Due to the difficulty of getting sharp neat bends in stainless steel by hand it is recommended that you use a Sheet Metal Folder or a Press Brake. Take the bigger panels down to a local fabricator and bend the lot in one go, each bend only takes a couple of minutes and is spot on every time. If you are lucky he will do it for free. This applies particularly to the 2 bends in the Seat Back Panel. Get these bent at 110 degs.

Note :- One of the more annoying features of this kit is the way the Seat Back Panel is mutilated to allow fitting of a Sierra fuel tank. If you are not fitting the Ford fuel tank this cut out can be used to our advantage. By cutting out a mirror copy on the drivers side you can finish up with a rectangular cut out approx. 7" x 13" giving access to the Boot from inside the car. (Safe and does not leak !!) If you pursue this approach, cut the stainless Rear Panel now as it is more or less impossible once the panel and the 3/8" ply Boot Front are in. It is easy to cut the ply out later using a jig saw and the 7" x 13" aperture as a template.

See the Fuel Tank and Boot Section XV There are plenty of photographs showing construction methods. Incidentally, the Boot Floor forms part of the Fuel Tank mounting assembly

As per the video bend up the Seat Back Panel and the place to one side. There is a problem with this panel. If bent as per the Video you will find that there is not enough clearance for the rear Propshaft Universal Joint. The rear tunnel sides need to be angled outwards to give about 3/8" clearance each side of the joint. (5 degs is about right) Once the Seat Back Panel and the 4 Tunnel Side panels are fitted temporarily we can turn our attention to the Pedal Assy and the Steering. See Section XIII. Once these are in we can return to the Interior Panels by fitting the Footwell end panels (2) The photographs make the general assembly quite clear. Note the position of the Passenger tunnel side panel in relation to the Handbrake cut out and the corner detail in the lower seat back panel.

Most of the panels will need trimming and fitting to suit. Note the battery box floor needs to be bent to fit into the Zed fold in the Passenger side firewall. It may however be better to fold it over the TOP of the chassis tube to meet the passenger footwell end panel, this makes the folds less critical and a neater job. Non of the firewall panels seem tall enough and once the car is finished a complete new set will be made to fit the bonnet line precisely. As I intend to fit a separate Scuttle & Nosecone some redesign of the firewall will be required anyway. As you will see later on, I have decided to fit the Battery in front of the passenger footwell panel adjacent to the Starter Motor. You may decide to fit the Passenger footwell panel to the rear of the upper chassis cross member, rather than the front. ie: 38mm to the rear. This will make all the difference to fitting the battery later on.

At this stage you will need to consider two very important components. One is the full harness seat belt mounting and the second is the handbrake. The upper seat belt mountings are pre fitted (4) and there are two pre-drilled brackets on the chassis members for the lower outer mounting points. (The SVA test now requires that the seat belt mounting bolts can be undone using one hand only. This means that the nut or thread must be captive) This leaves the inboard fittings. It is suggested that these are fitted to the short piece of 2" x 2" angle provided for the handbrake cable ends which is bolted to the floor pan. This means that at least two of the harness mountings will pass through the rear panel/floor panel. A very solid anchor point could be the inner ends of the Wishbone pivot bolts. Cutting holes in the sheet is much easier with the panels off the car but there are already cutouts at this point. A couple of 2" x 3/16" steel plates can be brought out through the seat back panel to the inside the car for the actual harness bolts. Another possibility is the Recaro seat mounting points. But make sure the seat is anchored to more than the St St Floorpan. Plenty of bracing underneath to something substantial. Your life and that of your passenger may depend upon it. Use High Tensile Steel bolts, High Grade Steel for the plates and Threadlock all the nuts.

The handbrake position has been a subject of some debate. It is said that with a non-inertia reel belt and short arms, you cannot reach the floor mounted handbrake. A possible solution is to fit the handbrake to the tunnel top. Modifying the Sierra handbrake to raise the lever, or to fit it to the tunnel top are well covered on the RHOCaR web site. (as is shortening the Sierra gear lever) It is a personal choice. Whichever method you decide upon, you will still need very secure mountings for the lower inboard seat belt mounting points and the handbrake. I have used 1" x 1" angle located at the rear handbrake hole and also picked up on the Recaro seat rails. A spur comes off the angle for the front handbrake mounting hole going forward to the chassis rail If you raise the handbrake lever you will need a cut-out in the angle for the pull rod to pass through. This angle would be better fitted at the floorpan stage when the car is upside down. Next time !!

Note:- Before final fitting the Tunnel Panels you will need to make arrangements for the various wires and pipes to pass down the Tunnel, 2 Fuel Pipes, Brake Pipe and Wiring Loom. One possible solution is to use 21.5mm plastic overflow pipe and clips. Use 4 per side and pop rivet before fitting the sides, feed the pipe in later. Keep the fuel supply and return pipes in its own conduit. (Is this OK for SVA) If required they can be pulled out in the future for repair etc. You will also need to make sure you can get at the Gearbox oil filler plug, (fill the Gearbox with oil at this stage) Reversing switch plug, Speedo Cable (use a 1:1 ratio 90 deg gearbox if possible, as this avoids the cable arcing across the floor.) and the Grease Nipples for the Propshaft (2) The rear nipple is readily accessible and the floorpan has a D shaped flap which can be prised open once a year to grease the front nipple. If you grease them now they may not require doing for 12 months or more. Once the tunnel is sealed it will be an awful job to get inside. The Tunnel Top is fitted at the Dash installation stage as the two fit together.

SVA Note:- At this point it may be a good time to consider the requirements of the SVA viz a viz internal projections in the passenger and drivers footwell area.. The regulations, quite rightly, consider this area of the car as important as the exterior and the 165mm ball and stipulated radii will apply. There are a number of ways to comply, either make sure that all the radii in this area comply or panel in the area subject to the regulations above the driver and passengers legs with suitable material, covering over any non-compliances. The regulations stipulate (and this applies to ALL SVA work) "material that a major motor manufacture could be expected to use", temporary work obviously designed to be removed after a pass will not be accepted.

Note:- The internal length of the foot wells is governed by the combined length of the tunnel side panels. The location of these is fixed by the cutouts for the chassis cross member (in front of the Handbrake mounting) If you loosely fit these panels you will see that the floorpan is too long, furthermore if you loose fit the passenger footwell panel you will see that the passenger tunnel wall sits inside the floor pan (from the Gearbox mounting forwards by about 3/4") You may decide to remove this excess material and this is best done before you fit any panels, better still before you fit the engine assembly. It may come in useful re the battery location. The drivers side footwell panel is virtually useless and it is best to make up a card pattern and manufacture a new panel. With care this can be made in one piece with a hole for the steering column shaft, much neater.

Go to Section XIII

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© Colin Usher 2005