DDK - Die Deutschen Klassiker

I have to say this turned out to be a BIG day. You never expect it to be straight forward and take the time you expect, but I didn't think it would take all three of us the entire day One complication after another seemed to arise and it's the first time the Special hasn't obliged with an easy and first time modification. Maybe it wasn't happy with it's nose being dropped a few inches towards the tarmac Barry in typically modest style "lent a hand with a bit of cutting and welding" which ended up being horribly involved and complicated - thank goodness he lives local!

The rear suspension has proved equally troublesome. Ian (Wolfsburg Performance Services 01932 701521) was going to get the Armstrong coilovers rebuilt but seems it's going to be more expensive than brand new but period correct Koni's as none of the parts other than the springs themselves are available, meaning everything has to be specially made. The Koni's are also bump, rebound and height adjustable and perform better, and given we've not driven the car in anger I'm expecting some significant fettling will be required, so that has sealed their fate I think.

Time for a bodywork update I think .

As you'll know, we went for a wire-form buck because it's a brilliant way of visualising / creating shapes for the body. Within a few minutes, subtle changes can be made to a curve, a shape or whatever. Cheap as well: the whole lot so far has barely used £100 of materials.

So great, the perfect solution ..... erm .

The problem is this: the wire is great for freehanding a style, and going all of the way down one side of the car. The trouble is then reproducing it on the other side. Trying to bend wire so that it exactly holds the shape of side one is almost impossible. Also, the 'master' side's wire form is held in with a variety of props and inner wires, meaning that you can't map the inside of the form.

Bottom line is that the more I thought about it, I came to the conclusion that the only option was going to be to reproduce side two in wood (known as an eggbox buck), having taken forms from the master side. Right in the middle of this dilemma I was due to go on a jig-making course (for some more projects I've got in mind), so I held off until then. Just the chance that they might have a magic bullet to get me back on track.

No, it turned out that most people are working from full drawings, or can take sections from an existing car, which is in effect, where we are. Therefore they agreed that side two would have to be in wood. Now I might well be missing something, but I think for us now, wood is the way to go, and that's what we're doing.

No regrets with the wire though: there's no way that you could create this sort of shape in wood, and then convey that to the customer in a way that he could visualise the project.

Now the first side is pretty stress free (design apart): if it looks right, it is right. With side two, things are getting complicated. How do you know when the wings are level? Spirit level? What if the car's not level? What if the floor's not level? What about how far in or out the wing comes? There's no one straight line that you can measure from, and no easy centre-line either.

Sooner or later the bullet had to be bit, and a decision had to be made as to what is the centre-line, and what is 'level'.

Level: I decided that the only truly level part around the front, as far as the car (and not the spirit level) is concerned was the two uprights from the suspension. Someone had put a wire-form in the way, so that had to be bridged:





So that gets a level. EDIT: this thing is parallel to the suspension towers on the top, and at 90d on the sides. This now gives me something I can put a right-angle or straight-edge onto: very useful indeed.

Next thing: where is the master wing (in and out)? Measuring off of the supension arms, I marked a centrepoint on the front of the wireform, and luckily have the screenwasher hole on the scuttle as a rearward centre-line.

With the centreline in place, I could then measure out to the top-most part of the wing at the rear, and scribe in a board to sit on the wing (there's some logic to this ..... ), and keep it parallel to my new centre-line. The previous 'level' board gave something to support the wing board, and ensures that the wing board remains upright:





With these in place, I could now start scribing in some MDF to the existing wire, in order to arrive at something I could draw around to create each station for the wooden buck. The problem that I was stuck on for ages and ages, was to come up with a method that could be translated onto a board for cutting, that could be referenced back to the wing. To put it another way, it's all very well scribing in a shape, but to get that to marry up to the one ahead and behind it in height, width, and twist, is a tricky old thing.

Anyway, as you can see, I marked to wing board on both sides, and it's kept vertical. The process for making each station is as follows:

1) Scribe in scrap MDF into wireform, keeping to reference line on wing board, and ending up with scrap MDF fitting the wire and the board.



2) Draw around this onto thick MDF to form first half of station:



And then repeat for the other side of the wing board. Of course you do need to factor in the width of the board as well when drawing the stations out.

I'm hoping that this method will give me a set of stations with the correct relationship to one another, and that they can be mounted onto the inside 'sister' to that top wing board: i.e. ultimately the underside of the wing board will be drawn around, and this will give the shape for the main wing 'spine' for the buck.



I should point out that we are going to have a weird (and ugly) buck now, where the nearside, the front and the rear will be in wood, and the master side will remain as wire (it might as well).

In fact the wire side will be the first to be built, as that can then yeald some soft 3D patterns to confirm that side two is as accurate as possible.

More in a mo ...[/img]

Loving it

Learning by doing!

It will be so much easier on the next car

Whilst this was going on, I had been giving some thought as to how to achieve some neat lines for the front edge of the clamshell, and especially, the return of the kamm tail to the rear.

As we had plenty of 18mm ply to hand, I thought that perhaps some basic (read: crude) hammerforms might do the trick.

The rear one represents the inside of the kamm tail: i.e. the metal will be laid over the side shown, and will be clamped there by a second similar, but smaller piece (not made yet). With the ally softened, it'll get knocked over the hard edge, hopefully forming a lovely neat and consistent return line. Well, that's the plan anyway. It only needs to work once, and with softened aluminium, I reckon it's got a good chance:





The more heavily curved part represents the top, whilst the lower is a much shallower arc. BTW, where needed, I've just used bodyfiller to blend any rough parts.

As for the front, I scribed around the outside of the existing wireform nose area, and transfered that to some more 18mm ply. This was followed by another layer underneath, and two more on top, all glued and screwed together.

Ultimately, I'll make up a little metal gauge to the correct radius of the nose, and mark-n-plane this form to match.

The idea is to build it into the main buck, and when the 'bonnet' is wheeled, sit the assembly over this hammerform, and after softening it (if it needs it), I'm hoping I can beat it over the form with one of my home-made beech panel bats (made from a neighbour's beech workshop from a rejected kitchen ).

Doesn't look much at the moment, but the foundations are laid at least:





More to follow ...

Oh yes, next course is on hammerforming, and using hammerforms to produce prototype and low production run parts: all useful stuff .

Now, as you might recall, there is the small matter of the English Wheel.

Well, I've been very good, and resisted playing with it up until a week or so ago.

With the buck situation somewhat in limbo, and glue setting on the above forms, I thought I deserved a bit of a play. I had brought along some scrap ally that had previously been destined to be arch liners. I only brought one smallish bit with me, but that was about right for a bit of rear wing.

I should point out that this was never destined to go onto the car, and indeed I wouldn't join panels in this area where this one starts and ends.

Anyway, using the new techniques picked up late last year from the Eckold wheeling course (very different from Rod Yates, and the folk at Contour as well), I came up with a panel.

Now, I'd love to say it just took a couple of minutes, and it was all a doddle, but it twerned . As soon as I started wheeling on my £2150 wheel, following my three day wheeling course, £1500 with lost work, and having committed very publicly to this build (not to mention the Contour courses and at least a year at Rod's), it was clear that I couldn't wheel. For toffee. At all.

As you can imagine, this wasn't a good place to be. The more I wheeled, the less control I had, and the worse the finish. It had started off as a piece of scrap, but my word, it was only getting worse. I called it a day for that weekend, and had a miserable week worrying about the whole thing.

Anyway, a flash of inspiration: I realised I hadn't levelled the wheels ( ): contary to popular belief (including mine until a couple of years ago), the bottom wheels (anvils) aren't a true radius. They actually have a flat on the very top. The tighter the curve, the narrower the flat, and visa versa.

By failing to level the anvil to the top wheel the flat (also known as a 'contact' or a 'blow') was just married to the top wheel on one 'corner' of the flat. So instead of having nearly 3/4 inch of contact, I had about 1/32nd inch.

This gave almost no control over the panel, and made it impossible to overlap the 'tracks' (wheeling patterns). With the use of a bit of copier paper (doubled over), the correct relationship was restored. Longer term I'll make up a mechanical lifter for this.

A truly amazig difference, and control was back again: now you can really feel the quality of the wheel, and feel confident in it's abilities.

Here's the result. Like I say, keep in mind it's heading for the bin (already in there in fact):

Barry - your scrap is beautiful! Keep them wheels rollin'

So things are looking up.

If you look at the above piece, you can see that the actual finish on the surface isn't very good.

This was because the top wheel of the English wheel was rather pock-marked from previous abuse, corrosion and dirt. I had a bit of an effort with some 1000 grit w-n-d paper, and that improved things quite well, with some impressive slurry coming off the thing.

In addition, the top wheel was very, very worn in the centre, meaning that the anvil flat (see above) actually showed as a contact to the left, a contact to the right and a gap inbetween. I gather that this wear is a result of of the metal of the top wheel gradually being pulled from the top wheel, and being left in the surface of the workpiece.

A conversation with a friend prompted me to take things further. He suggested that a diamond lap would be just the thing. Turning wasn't an option for me (I'm no engineer, and anyway, I'd rather leave that option open for the future should it be needed). That didn't rule out the lathe as a method of rotating the wheel though (as my father pointed out: I was all for putting a handle of the end of the English wheel's shaft).

In the end I turned up a mandrel for the biggest collet I had for the lathe, which then held the top wheel nice and true. With my sandwich box under the wheel full of soapy water (that definitely needs a good clean now) , I could start.

No pics on this I'm afraid, but basically the lathe was put into backgear, and the diamond lap (credit card sized, sold for touching up woodworking and engineering tools) hand held. After half an hour the individual scratches started to join up. After an hour there were two dull areas, with an un-touched portion in the middle.

After three hours, there was just a 6-8mm trough in the middle of the wheel, though much reduced in height.

Finally, the lap was flat on the wheel, and it was reversed so that the fine side could take over.

After another half hour or so, I switched to Autosol and Brasso mixed together. Finally I dashed up to the workshop this evening (third day in a row I've been up there ), and re-mounted it.

Using a DTI, it seems that the run-out is about .002": not perfect, but easily good enough. I might well have another attempt before the bonnet area, but I suspect that it will be easily good enough.

To complement the shiny top wheel, I've just ordered a full set of Hoosier anvils from the States. Reputed to be the best worldwide, they should give me the very best chance: which was the whole point in investing in a 'proper' english wheel, and the courses as well.

The whole point of this project is the learning curve for both Steve and I, plus the enjoyment of the journey. So far it's going to plan ....

The scrap bit looked great to me - you must have been so relieved when you worked out what the problem was

So just the 4 hours to get it flat then!

The 0.02" panel looks pretty good - that top shot is now my screen wallpaper

Beautiful stuff Barry

Only very small areas of the Astons were left as wheeled, most of it got a good going over with a body file and paper, but no harm in getting it as near as possible in the bare metal

Barry wrote:

The light line in the wing looks an ideal location for a feature crease line. If you need a wheeling/hammerforming challenge!

You can just see the remains of that central groove, but you can barely feel it, and the anvil flats will bridge it as well. I'm pleased, and am sure it'll be more than fine.

I forgot to mention something on the rear hammerform: the other idea I've had is to use the upper 'clamp part' (not shown) in combination with the base to form some 'factory' looking features.

Not sure yet, but probably raised areas for the rear lights to sit on, and probably some sort of trick return for where Steve wants the very good exhaust collector to exit.

The whole idea of these is that you can work the wood on the bench, reinforcing and smoothing it where needed, and using routers / jigs / sweeps and other tricks to de-skill the detailing. As an example, that top line that denotes the return on the kamm is quite easy to plane up. Easy to sight down and correct as well.

To try to free-hand that very precise, prominent feature would be very, very difficult, and just asking for a good piece to be reduced to scrap, and let's face it, there's going to be little shortage of that once I get going .

On that note, I'd like to point out (un-modestly) that the test piece fits the jig really rather well, and the latests methods I've picked up seem to suit my way of working with the panel. Different strokes for differnent folks I suppose, but it just shows that with panelwork there are often a whole load of ways of tackling the same task.

All for now, thanks for reading ...

Thanks Gary, oh and thanks for the feature line idea: I suppose that's because I've not got enough of a challenge .

With friends like you etc ....

It would look good though wouldn't it?

BTW, that panel started off with a lot of marks (Rod had already thrown the metal out, then I stacked a load of rubbish on it), and other than the final pics, was wheeled with the pre-cleaned top wheel.

I can't wait to try a brand new bit of ally in the wheel, as that will be the real test.

At the moment I'm still gunning for metal finish, although logic says it's not realistic for a first coachbuilding project. No harm in aiming for it though.

Gary71 wrote:It would look good though wouldn't it?

Nope .