This is the page where I will mainly track the progress of the plug making, Bodywork 2 will cover mainly mold and body panel making.

All references to pictures are to those above the relevant text.

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The plan...

I'd Imagine at this stage you'd be thinking that the image on the page background is a fair representation of the intended final shape, but you'd be wrong*. I have decided to go with a more of a sports racer/track car look. The traditional "seven" look is really not suited to mid-engined cars, but as I said from day one it was the spirit rather than the look that I was after. So really the car will still be light, simple, no frills and good performer (hopefully)

(* This was true when written, but as of Oct 1 the background does now accurately represent the intended finished shape, perhaps :) )

The first picture is some way off in terms of final details, air intakes, lights etc. But you should get the idea. The second gives some idea of how I plan to access each end.

Early stages

These two show the plug (or buck if you prefer) in progress. At this stage you see worst, crudest approximation of the shape. It will get better!
So far I've used 1/8" hardboard, which forms very well for the simple curves, mounted on a frame of 2x4, 2x2, and 1x2 wood. The white "filler" is pre-mixed sheetrock compound (plasterboard finishing plaster in the UK) which is cheap, easy to spread, and easy to sand. The final filling will be done with regular car body filler, but it's expensive to use at this stage (i.e. when you use a lot).

I'm currently working on putting a horizontal "skirt" all round the lower edges flush with the bottom of the frame. This will give a place for the lower flanges of the mold to be formed so that a return lip can be formed. (This will become clear as I progress)

  4/7/02:  

The pictures above show the "skirt" mentioned above. Also shown is the first forming of the fender (wing) top pieces. The second pictures shows a piece of wood next to the wheel, it is not fastened there, it just gives me something to take vertical measurements off and compare from side to side. The flat pieces that have become the sides of the wheel arch are marked from the same template, so side to side variations should be minimal. The skirt, being flush with the frame bottom, is also a good datum for measurements. It's strange how perspective works, the "hood" (bonnet) part looks almost parallel, yet it is a long way from it! Pictures 3 and 4 show more progress on the front. The end of the hood was done by stacking about 6 pieces of expanded polystyrene (Styrofoam ?) cut to shape with a flame heated hacksaw blade (worked well!, but be careful of the fumes, and setting in on fire!) The shaped stack was then covered in the white filler. Incidentally, if you didn't know, regular car body filler (Bondo) can't be put onto polystyrene because it just dissolves it.

My plan is to get all of the body to the white filler stage (my version of "body in white", tee hee ) then step back, have a good look, and the add "features", vents, scoops, ducts etc. Then I will finish in "Bondo", final sand and paint, and repeat until ready for molding. Or, then again, I may have a different plan.

Outside viewing

I could not resist the temptation to push it outside for a look. Good idea really, it let's you get a real good look at it, which you can't do from 5 or 6 feet away! There are one or two areas I want to address (besides finishing the damn thing!) but generally I was quite pleased. The side does have a duct/scoop added and, although I said I'd add features later, this was probably easier to do now (plus I could always use my change of plan clause!) The "driver" (my son, who conveniently appears when something cool is happening!) is about 5"10" to give some idea of scale. The second picture is a rendering of the proposed roll bar cover and rear "fins" which should help to distract visually from the engine cover (not shown). The third picture shows that the hood (bonnet) part is definitely not parallel as it appears above in an earlier in shop picture.

Rear fins

Rear fins, roll bar cover and engine cover under construction. I find that the best way to join the hardboard is to run wood in the corners (behind the joint) if possible, then glue and screw and clamp the joints. When the glue is dried I remove the clamps (yeah, obvious I know) and the screws. Lack of screw heads helps filling and sanding a lot! I can see that when I have the rear end more completed that I'll have to wheel it outside again for a proper look. You may possibly wonder why I only show the side scoop down the drivers side? Yes, of course, it's the only side done! I thought time was better spent moving onto new areas rather than copying half of it. If I need to make a big change to the side I then only do it once (and then copy it !) The "solid" panel (under the roll bar) is actually cut out now, but still has extra allowance for mold flanges. 04/26/02, added 4th picture showing cut out

Arches

Some arch detail in progress. The first picture shows the inner arch piece which basically just acts as a dam to work against and gives somewhere for the mold outer lip to form (more later). The second picture shows some blocks of Styrofoam roughly cut to shape and stuck in place with the white filler. At this stage it's very easy to shape (and consequently easy re-shape when you rip it off because you don't like it!)
You will notice the roll bar cover and fins part not fitted at this stage. I decided to keep it removable for as long as possible so I could keep trying it both fitted and not fitted and keep comparing the looks. If the fins/roll bar cover could stay a separate part that would be ideal so I'll work towards that if I can.

The first picture show some progress on the rear arch, and the second shows the right/left hand drive version! OK, I mirrored half the picture to give an idea of what I'm doing at the rear. The third picture is pretty much the same but from a higher viewpoint.

The good thing about this method of plug construction is this ease with which you can change things. I decided, after further study and consultation (thanks Steve) that the rear arch wasn't right. Too much MK1 Escort rally car IMO, not that there's anything wrong with that (I had two myself!). So, I blended the front edge into the rear edge of the air duct and followed the line of the air duct top edge into the arch top edge. A little more integral now I think. The first two pictures show the arch mods. in progress, and the third picture gives a more updated idea as to where I'm going with it. 

Reworking the arches

The first picture shows how I'm reworking the front edge of the front arches. The far one (left, looking in the direction of forward travel) is the modified one, the front edge being moved back about 3" to reduce the bulk in front of the wheel. I couldn't go any further back as the lights have to go in, and preferably at a legal height. The second picture shows the rear edge of the arch blended back into the body, it helps to visually balance the arch. Picture three shows how I've rounded the rear corner more, and finally in the fourth picture you can see some detail on the leading edge of the rear arch.

You may wonder (or not) what the black is? It is simply some aerosol spray paint put on on to highlight the undulations, which are harder to see in matt (flat) white.  

Outside again

Well, obviously, two outside pictures first. Since they were taken I removed the "hood/bonnet" in progress so I could work on the dash/scuttle area. Near the top of the page you can see how I intended the whole front end to hinge forward, well I changed my mind. Now, just the hood/bonnet will open. This means that I can save some materials and weight by not having the whole front rigid enough for hinging. The third and fourth pictures show work in progress on the dash area. Picture 3 shows a fan to help the filler dry because of how wet it is here at the moment. (In case you were wondering)

Phase two

I've now officially moved into phase two of the plug build. Fairly meaningless but at least I get the satisfaction of a milestone to cross off! Phase one was getting all the body it's first covering of white filler and achieving the first iteration of the the body shape. Phase two is refining the shape and adding the details.

The first detail is the grille, and reshaping the front skirt is the first refinement, both shown above. You will notice I've changed to ply mainly because of it's extra stiffness, and gone to two layers. The first layer really is just to form the back of the grille area which will be cut out on the finished molding. and the second layer allows some small lips to be on the finished opening, rather than just cutting a plain aperture. The refinement of the shape is basically pulling the corners back now that the wings/fenders are shorter and giving it a constant radius rather than a flat with two radiused corners.

07/06/02, added picture 4. Work in progress on the grille area, notice how I'm aiming for a sharp corner on the near vertical edge. It's easier (voice of experience here:)) to form a sharp corner first and then sand the radius onto it. If for no other reason than it is easier to measure from the sharp edge back to datums and center lines. Try measuring something that is all curves and angles and you'll see what I mean. The plywood edge has a small radius on the front edge and it's rear edge makes a good place to fill to, a bit like shuttering concrete really. 

As I get areas of white that are reasonably true say within 0.02" (0.5mm) of true surface I'm going into Bondo mode. I'm using it as a form of thick hard paint that I can rub down to a good finish. My theory is that by using a notched spreader on my first coat and a smooth one on the second I can get a fairly consistent coating (see picture 2 for my theory) Of course this may the correct and normal way to do this, but I just don't know!
It's worth mentioning at this point (if you hadn't already figured) that some of my procedures are experimental and I may end up re-doing a load stuff. If I didn't mention earlier it's probably 15 years since I last made any plugs and mold, let's hope I remembered the the important bits. Time will tell I guess. The third picture would be "guess my hobby?" not many would say building you own car would they?

Reworking the rear

Finally decided to do some major mods. New back end!. I've tried to recreate the same hard edged gentle curve as I did at the front to add a little cohesion whilst still keeping the curves towards the rear (picture 4 below, the high rear view, shows what I mean)

Picture 1, the old rear chopped off. 2, trail fit new plywood panels. 3, glue Styrofoam under new edge to be, to support panels and provide backing for filler on the corner. 4, inside of the new panels, showing glued on blocks and filler backing behind the join.

Picture 1, new rear panel fitted. 2, view of rear with filling and blending partially completed. 3, as picture but different angle. 4, as before, but high rear view. 

Once more notice how I'm trying to create sharp edges first and the create the radii later.
If anyone tells me that they preferred the other way, do not leave any means of contact. I WILL track you down : ) Seriously though, constructive comments, good or bad, are always welcome.

Back to phase two

Moving on again with phase 2, the "pink" phase I guess. Picture 1 shows where I spent some time adding draft in the inside face of the arches, and where I've started the pink filler (Bondo). At some time during the plug making process you have to give some thought to how the mold will split and the parts will come out and sometimes add some extra draft, hence pic 1. Picture 2 shows where I've added more material to reduce the arch opening, this is give a little more leeway when I come to cutting out the openings in the finished molding.

At this stage it's probably worth listing a few observations. These are just my findings and not necessarily good practice or recommended, but they worked for me.

1 - Polyester filler (Bondo etc.) does attack Styrofoam (as mentioned earlier) but, if little bit of filler does touch a bit of foam it's not exactly a nuclear meltdown scenario! It eats away and dissolves a little but not much, so basically if it is exposed through the white filler I've just been ignoring it and filling on top of it. <runs to workshop to check it hasn't burnt down>

2 - The surface tolerance of the white filler can be relaxed to 1 to 1.5mm (0.04" to 0.06") as it is easier and more productive to spend the time getting the pink filler right. It looks as if I'm on target to use 4 or 5 gallons of Bondo and at around $10 to $13 per gallon, so another tin will not kill the budget.

3 - As mentioned previously, create sharp edges, and radius them absolutely the last job.

4 - Don't try to spread the Bondo too thin, it's just too easy to rub through especially on corners.

Picture 1 shows the right front arch after two layers of Bondo (1 notched and 1 smooth, see above) first sanding and patching and then the second sanding. Notice that because all main bulk of Bondo is on I've gone ahead and formed the radii. Picture 2 shows some primer on the arch and the other side part way through the matching process, using templates, radius gauges, and other black magic : ) Picture 3 shows the first gloss applied, definitely not perfect, but encouraging nevertheless. Let's hope every further fill, rub and paint cycle shows improvement. Black, as you may know, is the worse possible color for showing surface blemishes and undulations, hence it's use at this stage.

I was asked on a forum how do you match one side to the other? I think this is a good question and basically this is what I said:

The side to side matching is done several ways: 

1 - Make the basic underlying forms as accurate as possible. 
2 - Keep edges sharp as long as possible to measure from. (i.e. don't radius too soon, did I mention this before?) 
3 - Have accurate datum and reference point on the skirt to measure from. 
4 - Use templates to match curves (make one good side, then make the template from that) 
5 - Use digital photography. Photograph the same feature on each side from the same relative viewpoint, then mirror one image and overlap onto the other to show any discrepancies  

Another good point crossed my mind too, after thinking back to my previous encounters with GRP.
Getting the best possible finish on your plug IS important, but IMO it's more important that you have no high spots, and that any minor blemishes that you don't deal with are of the sunken type. Why?, well when you make the mold those scratches or pinholes that you may have missed become raised features which in turn will be polished out (or sanded if bad). In fact trying to fill tiny pinholes on an otherwise perfect surface could be very counter productive. Again, this is just an observation on my part rather than a proven technique, and I'll stress again that a good finish on the plug is important. 

Reworking the arches (again)

   

After thinking over some possible re-design options, and getting feedback from my focus group : ) (thanks guys!) I decided to rework the rear arches once more. Hopefully this should give a more integrated look to the whole shape, picture 1 shows work in progress. I'm aiming for having one complete side primed in about a week or so, but as always, we shall see. Picture 1 shows work in progress, picture 2 shows er.. work still in progress! This time the wheel is back on to get a better idea how it will  look. Notice also the distinct bumps in the engine cover, something else that will need attention. Picture 3 shows some work on the cockpit side. I'm going to put a flange along the line you can vaguely make out in order to create a downwards return to make trimming easier (good idea, thanks Jack!) 

Added picture 4. It shows a mod to the body each side of the engine cover, I've added about an inch to give a more gentle curve rather than a kink on the transition between the sides and the rear. Also, it reduces the perceived height of the engine cover. I think it looks better, anyone agree/disagree ? 

After recommendation from Dennis, I obtained a body file/hand sander (pic 1). It really does make it a lot easier to get the flat areas truly flat, and the curved areas true to profile too. Pic. 2 shows the Bondo layer on the re-shaped rear corner.

Thanks to everyone who has offered their opinions at this stage. I expected that there would more diverse opinions than there actually has been. Everyone has been positive and in general agreement with the way it's going, and any criticisms have been minor (and I agree with most too). Again thanks. 

Getting one side closer to finished...

Ok, picture 1 shows a coat of paint on all of one side, it is a paint called Kilz and is readily available in the US. It's really a primer that is good at covering  stains and potential bleed through, but it dries quickly and, importantly, dries very hard. Picture  2 shows above the arch after some rubbing down with 600 grit wet and dry, some minor imperfections are still there, but will come out in the mold easier. Picture 3, more re-work/design changes. Some subtle changes to the intake duct area, a bit nicer I think.

OK, side one is pretty much finished shape wise. A little minor finishing and final sand/polish is all that is needed. Picture 1 shows the subtle changes around the air intake area and picture 2 a general view from the front. Some of side two is fairly close to matching already so hopefully that shouldn't take too long.

Onwards to the other side...

Pictures 1 and 2 show the first fill, over Styrofoam blocks. The cracks are no problem, they help to key the next layer. Pictures 3 and 4 show the second layer applied. Time for some profile matching.

Pictures 1 and 2 are both self-explanatory really. Some work is still needed of course but it's getting close. Picture 3 is the right-hand rear corner, whereas picture  4 is the left-hand rear corner mirrored for comparison. The two shots aren't from  similar enough viewpoints to be used for accurate matching, but I'm sure you get the idea.  Accurately taken pictures can be laid over each other with one faded to investigate the true contour matches.

The templates are good for confirming that a localized profile  matches a similar profile on the other side. However, you can't be certain that the position of the template is mirrored accurately, so some key points need to be measured relative to a fixed datum plane on the car centerline. Picture 1 shows what I devised to do this. It is two tubular stands with a piece of aluminum angle clamped between and leveled. Then, two 3 foot rules are riveted to the angle about the center. The whole structure is then aligned square with the car centerline and centered.  Picture 2 shows the device from the side. 

Picture 3 shows it in use. It is simple to transfer measurements by measuring the x and y co-ordinates of relevant key points in the format, x from center and y down. One or two discrepancies have been discovered and since corrected, and once they key points are validated then the templates can be fully trusted. I hope I didn't say this body stuff was easy :-)

Picture 1 shows a high up rear view. I like this view, it shows the curves quite well, but I'm not sure if the corners near the lights need softening with more radius or are better left hard as they.  Picture 2 is  just a lower side view of the same. Picture 3 shows where I have hacked out for the license plate recess, picture 4, where I've started to fill it! i knew there must be a use for those CDs that keep I getting sent :-) just about the same size as the lights I'll use. I've also been doing more filling on the left side and it is getting close to Bondo time. 

Picture 1 is a very rough sketch of where I'm going with the rear. The lights can be either mounted in the body direct or into mesh as shown. The mesh can be either black as shown, or even painted body color. The same goes for the lower side vents. Picture 2 shows my response to the survey above. Most people like the harder edge so I'm just softening it only very slightly. Picture 3 shows it after filling, and with Kilz just brushed on. It works as well spraying, just needs more rubbing down, great for small areas like this. Notice the comparison with this and picture 2 in the selection above these. It is very subtle, but in the flesh works well IMO. Added picture 4 (10/27/02) showing matching work in progress. The slight radius increase at the corner seems to show up better on this side because of the lighting. I must say also that the rear arch shape is really growing on me now, I wasn't too convinced at first, but the majority of opinions offered were in favor of it. Rightly, it seems. Added picture 5 (10/27/02) to show a more side on rear view.

Also, from the "survey" the suggestion of a rear diffuser was mentioned (thanks Terry). This is a definite possibility but would be as an add-on into the mold rather than trying to figure it out now. The reason being is that I must consider the hinging of the rear and the fact that there is little distance from the body rear extremities to the frame (maybe 10"). This would limit me to a fairly small vertical dimension in order to keep a reasonably shallow angle on the diffuser.

Picture 1 shows my co-ordinate measuring fixture now moved to the front. Not because I'm just about to work there, unfortunately, but because I no longer need it at the rear. All my key datum points at the rear have now been validated and I can work just with the templates and photos.  Picture 2 shows how I'm going to finish the engine bulge. The flat area at the front is OK but the two distinct bumps will be turned into one gentle curve. Also shown is the reasonably good finish you can get from the white filler alone, this still needs the Bondo layer! Picture 3 shows some progress on the filling.

Picture 1 shows the first Bondo layer going on the left hand side. Picture 2 shows the engine cover progressing a little. You often find yourself working in two or areas at once rather than standing idly waiting for filler to harden/dry (it seems take forever when you wait). Picture 3 shows the left rear corner from about as far back as I can get within the shop.

Picture 1 shows the next stage after getting the engine cover fairly flat.....making it convex! I don't want any tendency for the moldings to appear concave so I'm adding some definite convexity to it (Thanks Jack, for the clarification on that). 

You may be able to see that I have used an old vee belt laid along the center line, to give me around half an inch of rise in the center, and then filled between the belt and the edges. Picture 2 shows the second filling. Oh, and yes, the belt will be removed and the gap filled.

Meanwhile, more first layer Bondo is being applied to the left body side. (trust me on that, I don't think it needs another picture!) Picture 3 shows a high view above the rear with the engine cover area close to finished (in white filler). Picture 4 shows the engine cover with the first Bondo layer.

These three pictures don't particular show anything new other than further progress. The engine cover is ready for paint and the rear corner is filing nicely.

Reworking the front

A quick survey showed unanimous support for reducing the bulk ahead of the front wheel, and after a little study and some re-measuring I found that could cut 3" out of the arch area and move the front back. The pictures show the story of how that happened and are in order of the steps I took. The blue disc is a Styrofoam piece that I will be using to form my mold flanges on which in turn will give me the returns on the edges. It was placing this disc in position that highlighted the visual imbalance, which was subsequently confirmed by some fellow builders. (Thanks guys :-)) 

The problem was caused by me allowing ample room for lights to be fitted at the legal height. It transpires that it was in fact too ample. Some of the pictures show a light outline sketched on the side.

Finishing the rear

Pictures 1 and 2 show some detail finishing of the plug flanges. Pictures 3,4, and 5 show the rear painted in gray tinted Kilz. 

It is almost certain that all mold making books would tell you to finish a plug completely before making any of the molds or mold sections. Needless to say I'm not going to do that, for several reasons, some good some maybe not. Reason one, once I have a large area cleaned, polished and ready for molding I'd like to make the mold to cover and protect the plug surface. Reason two, it is important to allow the molds to cure well before breaking them off the mold, doing them with a little time break between will help this. Reason three, I need a break from filling and rubbing down!

Ok, so when does plug making become mold making? Lets say from here onwards. Bodywork 2