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How to make an MG TC bodyshell?
choc-ice - 10/8/15 at 09:17 PM

I'll throw this one out there because I'm stuck. But I'd like to say thanks to SteveWallace for his patience when asking him about his TC.

I'd like to make an MGTC, an authentic car is £25,000 which leaves me about £24,000 short. Even a resto project is £10,000 upwards and the price of spare parts (like a front wing or body tub) is insane. I've made 1:32 scale model cars that run on a Scalextric track, how much harder can a real car be...?



Originally I thought about using a Bedford Rascal running gear but they only have a chassis from behind the cab, so the front part of the chassis with engine mounts would have to be designed and made by me anyway. The advantage of this base vehicle is the size - an old MG is a very narrow vehicle and I don't want to use something that looks too wide, I'd like it as authentic as possible.

Plan B is to use an MG Midget as donor vehicle, it's pretty much the right track width, you can get hubs for wire wheels and if I can possibly sell some of these to cover my costs then an MG based on an MG would sit right with customers I think. The part that I'm stuck on is how to make the bodyshell.

I've got no experience with fibreglass other than owning a couple of fibreglass cars in the past. I've read a few articles, watched a bit on youtube and the more I see the more I think the chances of me achieving a good product in my garage is slim. You need to take a mould from an original but my cunning plan is to 3D scan a real car then get the buck machined using blue foam. However the machining something that size isn't cheap either.

I then wondered about getting the parts done as vacuum forms, I visited a potential supplier last week and again the tooling cost is several thousand pounds just for a single front wing.

If I get a frame made (like the ash frame on an original) it's possible to use sheet plastic, but it should fold over itself as you can see here along the top of the door and the rear quarter panel, which plastic wouldn't be good for.



Maybe thin sheet metal like the original? I really want something that can be made with minimal, or cheap tooling.

The other tricky area is the scuttle - the panel between the windscreen and the bonnet. Everything else has a curve in one direction but this has a complex curve with the double bubble over the dashboard, is there any way to make this other than GRP?

Any words of advice you can give me would be appreciated! My day job is a mechanical design engineer so I've got 3D CAD skills and tools, I've got an amateur's working knowledge on chassis and suspension designs and I've got some local suppliers who could make a decent part in sheet metal and some machining.

Gareth


Wadders - 10/8/15 at 10:51 PM

How authentic ? Are you talking about an exact replica of the MG or just something that looks period.

This might be a good starting point

http://www.ebay.co.uk/itm/kit-car-project-burlington-arrow-/131574736785?hash=item1ea2772791


IIRC the body was intended to be made from plans out of plywood skinned in thin ally sheet, possibly on a triumph herald chassis ??


coozer - 10/8/15 at 11:07 PM

Why not just build a Jaguar SS?

Saw this at Stoneleigh a few years ago and was very impressed....


choc-ice - 11/8/15 at 05:58 AM

quote:
Originally posted by Wadders
How authentic ? Are you talking about an exact replica of the MG or just something that looks period.

This might be a good starting point

http://www.ebay.co.uk/itm/kit-car-project-burlington-arrow-/131574736785?hash=item1ea2772791


IIRC the body was intended to be made from plans out of plywood skinned in thin ally sheet, possibly on a triumph herald chassis ??

I'm after something authentic, those replicas are always too wide and the wheels are too small. But the idea of how they are made is great, thank you. I've ordered a set of plans to see if that helps.
quote:
Originally posted by coozer
Why not just build a Jaguar SS?

Because I don't want one, Suffolk Sports Cars already make one, a replica SS is even more expensive than a real MG and if I built one from scratch I'd have exactly the same difficulties I'm having with an MG.

Otherwise, no reason at all ;-)


JC - 11/8/15 at 06:17 AM

Help is always give at LCB to those who ask


mark chandler - 11/8/15 at 09:21 AM

Herald chassis is a good shout IMHO as you can rebody and keep away from IVA saving £££

The body looks like it is mostly straight panels with single plane curves so you need to construct a frame (tube or ash) and dress it with an aluminium skin, wheel arches will be your biggest problem, have a look at alternatives you can build out or bite the bullet and get the correct items.


Wadders - 11/8/15 at 09:57 AM

How about this for a good base, no IVA and a 1935 reg plate. http://m.ebay.co.uk/itm/Morris-10-chassis-rolling-1935-hotrod-kit-car-replica-classic-pendine-racer-/331619102700?nav=SEARCH


David Jenkins - 11/8/15 at 10:02 AM

Well, here is what Ron Champion was working on while he worked at Oundle School... he was going to write a contruction book for it...

Oundle-1
Oundle-1

Oundle-2
Oundle-2

oundle-3
oundle-3

oundle-4
oundle-4


True to form, he didn't finish the book (if he ever started!)


cliftyhanger - 11/8/15 at 10:21 AM

Building accurate replicas is a nightmare, all too often they fall down on the expensive details.

If you want it to look identical, I suspect the cheapest route would be to spend the money and buy one. Defeatest I know, but it will only appreciate in value.

If you want a kit, there used to be plenty of plans out there for building a variety of 30's style cars, often ali or even cloth over ply. But starting from scratch is mighty hard and usually rather expensive.....


myke pocock - 11/8/15 at 11:19 AM

Do a search for JC Midge. I built one but on 13" wheels. With 15's they can, with a bit of ingenuity with the body look the dogs bits. They come up occasionally on ebay at a reasonable price and pre registered which would save IVA.


choc-ice - 11/8/15 at 11:50 AM

quote:
Originally posted by JC
Help is always give at LCB to those who ask

That’s the one I found, thank you. I’ve ordered a set of plans to see if the bodywork construction can help.
quote:
Originally posted by mark chandler
Herald chassis is a good shout IMHO as you can rebody and keep away from IVA saving £££

The body looks like it is mostly straight panels with single plane curves so you need to construct a frame (tube or ash) and dress it with an aluminium skin, wheel arches will be your biggest problem, have a look at alternatives you can build out or bite the bullet and get the correct items.

The Herald is too wide, plus I’ve heard that you either like Triumphs or MGs so I suppose the world stops turning if you make one out of another? It’s like the rusty car version of nuclear fusion.

Agree about mostly single plane curves. Except for the scuttle and wings it “should be” straightforward.

quote:
Originally posted by Wadders
How about this for a good base, no IVA and a 1935 reg plate. http://m.ebay.co.uk/itm/Morris-10-chassis-rolling-1935-hotrod-kit-car-replica-classic-pendine-racer-/331619102700?nav=SEARCH

Yes, but that only gives me a chassis and I’d have exactly the same problems trying to make a body.

quote:
Originally posted by David Jenkins
Well, here is what Ron Champion was working on while he worked at Oundle School... he was going to write a contruction book for it...

True to form, he didn't finish the book (if he ever started!)

That looks like what I need. Do you have any “in progress” photos of it?

quote:
Originally posted by cliftyhanger
Building accurate replicas is a nightmare, all too often they fall down on the expensive details.

If you want it to look identical, I suspect the cheapest route would be to spend the money and buy one. Defeatest I know, but it will only appreciate in value.

If you want a kit, there used to be plenty of plans out there for building a variety of 30's style cars, often ali or even cloth over ply. But starting from scratch is mighty hard and usually rather expensive.....

Your defeatist answer is the one that keeps staring me in the face, I know you’re correct. But if it was made without a roof and just with aero screens then the only expensive detail would be wheels and tyres, that’s not too terrible a situation. Hopefully the Burlington plans earlier will give me a starting place for a wood frame and thin metal, perhaps I need to see how the original MGs were made too – that was a similar construction so I wonder if most of the bodywork sheet metal was only blanked rather than had form tooling.

quote:
Originally posted by myke pocock
Do a search for JC Midge. I built one but on 13" wheels. With 15's they can, with a bit of ingenuity with the body look the dogs bits. They come up occasionally on ebay at a reasonable price and pre registered which would save IVA.

I’ll have a look, thank you.


cs3tcr - 11/8/15 at 03:06 PM

You might want to check out the "how its made" episode on building wood framed sports cars (Morgan), it gives a bit of insight into building the coachwork: Morgan

For TC's, most of the body panels (in steel) are more or less single curve though they do wrap around the timbers at the top and bottom. The scuttle panel is the tough bit, and may prove to be easier to build in fiberglass. Wood kits are available from the usual suppliers if you're wanting an exact replica. The chassis is another story, they were constructed from channel and aren't that stiff. If I were to build a copy, I would opt for rectangular hollow section, though the front of the chassis poses a problem if you're wanting to use a solid axle (as per the original).

I've often toyed with the idea of building an MG Q-type style car for myself, but finding a suitable front axle and the cost of either 16" or 19" wire wheels has kept the idea an idea. I already have an MG Midget axle, gearbox and a Coventry Climax 750cc engine that would be a perfect fit in a smaller pre-war style sports car.

Rod

[Edited on 11/8/15 by cs3tcr]


David Jenkins - 11/8/15 at 03:43 PM

quote:
Originally posted by choc-ice
quote:
Originally posted by David Jenkins
Well, here is what Ron Champion was working on while he worked at Oundle School... he was going to write a contruction book for it...

True to form, he didn't finish the book (if he ever started!)

That looks like what I need. Do you have any “in progress” photos of it?




No - that's all I ever saw of it. I went on a trip to visit the school workshops with a load of other Locost builders and there were lots of part-made cars around, including that one. There was some discussion afterwards, but it disappeared - I think SVA might have had something to do with it.


ettore bugatti - 13/8/15 at 10:54 PM

Check your local Ebay or your worldwide autojumble for a book called:
Sports Car bodywork by B.W. Locke

That should have the information you're after.

So yes ash frame, aluminium panels. Scuttle could be hammered on a sand bag, but GRP might be quiter for the neighbours.

And why not go for TC parts?
http://www.mossmotors.com/sitegraphics/index/mg-parts/mg-tc-parts.html


choc-ice - 16/8/15 at 08:20 AM

Going for some genuine parts is a stroke of genius - if the scuttle top is the most difficult part then actually £350 for a metal one isn't a bad way to get out of the problem.

I remember seeing that book around old book shops but the www thinks they're £60 now! I'll keep an eye on ebay for one.

I found this too, which seems to show the whole thing can be made in about half an hour, or at least a TD can.


David Jenkins - 16/8/15 at 09:26 AM

That video just makes me think that I would NOT want to try and make an MG TC body! So many forming and building jigs, plus I'd bet that the ash for the frame is hard to get in decent quality, and horribly expensive. What brought it home was when he fitted the steel side panel to the frame, and it just needed the odd tap with a mallet to move it into place perfectly.

Making a replica at home would be non-trivial, and I'm someone who loves woodwork! I will admit to disliking panel beating though, mostly because I'm never happy with the quality I'm able to produce. There's a bloke in Colchester who runs panel beating courses for amateur car restorers and I've often been tempted as it's not too far from me, but it's a skill I'd rarely use so would lose the benefit quite quickly.


choc-ice - 16/8/15 at 10:33 AM

Agreed, you'd be there forever making it that way. But that was from a time when materials were expensive but labour was cheap, nowadays it's the other way around.

If you had a frame that did the whole of one side, formed to the body tub's curve, then it wouldn't be too bad to put thin metal over it?


Volvorsport - 16/8/15 at 10:53 AM

Designing and building cars by Andre jute , covers building replicas.

If you cant afford the wheels scuttle and grill , then it will never look like a tc ...

I thought a jba falcon was pretty close tho...


choc-ice - 16/8/15 at 02:57 PM

Cool, another book I've just ordered!

You're right that the details need to work, if I see another vintage car on 14" steels with wire wheel hubcaps I think I'll have a nosebleed. But if I can get the proportions right and the major details I think it'll look good. A bit like Suffolk Sports Cars do with their SS100 but for a more affordable price.

The JBA Falcon is too wide and the door line is too high. It's not a bad effort (he says, having achieved nothing so far) but I'd like to do better.


Volvorsport - 16/8/15 at 04:17 PM

Don't forget the marlin roadster either , probably the prettiest of the lot , an started off like you as a one off...


choc-ice - 6/7/16 at 04:40 PM

Wow, has this really been sitting in the doldrums for all this time?

Well, in my defence we had a house extension done and I didn't believe how much time (and money) that ate up. It continues to eat up the money with "finishing touches" like the garden, decorating etc.

I've had a few more thoughts on doing this, here's what I've got so far.

I'm going to use an MG Midget running gear, my datum point is the rear axle so in my head the position of the Midget rear axle is overlaid to the TC location. The Midget propshaft will be standard and that gives the position of the gearbox and the engine too. The front suspension will be moved forwards to match the position of the TC's front, the TC wheelbase is 14 inches longer than a Midget.



In terms of the Midget's hardware, it means taking the mechanical components plus the front chassis legs and front crossmember. The Midget uses the front suspension supports as engine mounts so I can use the front chassis legs with their crossmember and suspension supports and fabricate new engine mounts to suit.



The chassis will need to be fabricated, I think mild steel thin wall rectangular section tube will work. I need to pick up on the Midget's front chassis legs, continue backwards to where the new engine mounts will be, then it's a bit vague until it picks up the rear spring positions. The Midget's rear springs are quite wide as you can see below, the TC used outriggers which doesn't seem necessary if I make the chassis wide.



With all these thoughts in my head and after lots of sheets of paper, I started with a CAD model of the finished car



I put some wheels on, as much to check the scale of the 3D model as anything else, the wheelbase is now correct



I sketched in a chassis, it's very approximate for the moment as I can't find any dimensions for the Midget parts and I don't have one to measure!



Bodyshell image removed, this better shows the shape of the chassis. I'm going to use a flat panel for the sides so all I need to do is put the ends of it in the right shape in both planes. This could be with metal supports fixed onto a plate which is bolted to the chassis. I want to be able to remove the bodyshell in one piece rather than remove it in sections. At the rear is a machined profile which gives the shape of steel hammered over an ash frame. Mine will be machined from plastic.



Next I sketched up the body shape as a flat piece. The idea is to make it from thin ABS or Polycarbonate, the same as the rear machined section and then I'll plastic weld them together. The doors can be done in a similar way, perhaps a bit simpler but still thin plastic sheet stuck to a machined solid part (made in sections to avoid too much material waste).

Getting this far allowed me to get quotes in and so far it looks favourable. Making a fibreglass shell would be great but I don't have the skills and I'm sure the cost of the buck would be extortionate unless you're making a few. The front and rear wings will have to be fibreglass as will the radiator grille (probably), the scuttle is too complex to make in anything other than a press tool or a fibreglass mould so for the moment I've planned to use a metal one as they're only a few hundred pounds. I'd like to use metal wings too but they are a couple of thousand pounds each

Any thought if I'm on the right track?


britishtrident - 6/7/16 at 05:58 PM

A TD or TF would be a more suitable choice to replicate because they used ifs and a stiffer frame. the TA/TB/TC had an axle mounted above the chassis as did proper Morgans.


choc-ice - 6/7/16 at 06:04 PM

Very true, but I don't like the look of the TD or TF, and if I did there are plenty of replicas around already I could buy.

I did toy with the idea of a solid front axle but that seems like a huge amount more work and I've got no idea where to start looking for commonly available parts.


Ugg10 - 6/7/16 at 06:24 PM

Any use?

THE JC 'MIDGE ROADSTER' HAND BUILT SPECIAL PLANS/PATTERNS BUILD INSTRUCTIONS


britishtrident - 6/7/16 at 06:42 PM

quote:
Originally posted by choc-ice
Very true, but I don't like the look of the TD or TF, and if I did there are plenty of replicas around already I could buy.

I did toy with the idea of a solid front axle but that seems like a huge amount more work and I've got no idea where to start looking for commonly available parts.


You must like ugly.
The TF was one of the best looking production cars ever


Sam_68 - 6/7/16 at 07:28 PM

quote:
Originally posted by britishtrident
You must like ugly.
The TF was one of the best looking production cars ever


Shoulda gone to Specsavers, BT: I'm with choc-ice, here - the TD and TF are the fugly ones, and were generally criticized as such in-period due to the nose-heavy look created by the radiator in front of the axle line. In terms of 'vintage' aesthetics, that's just the biggest bungle you can make! The smaller wheels don't help, either. The TC was much prettier, I reckon!

In terms of the JC Midge, one thing it might be useful for is the construction technique: IIRC, it the main tub was made of decent thickness plywood, but faced with very thin aluminium. Relatively heavy, perhaps, but it gives you the advantage of a much simpler timber sructure than the old ash framing techniques, and the thin aluminium (supported by the ply) is supposed to be very very easy to form.


choc-ice - 6/7/16 at 07:44 PM

The Midge is interesting, I don't need the full size plans for £99 but a paper copy will probably show enough detail for a tenner, thank you.

Looking at photos of the Midge they look quite slab sided, think it's possible to curve the sides in at the bottom and from the seats to the scuttle? I'm sure my idea of thin sheet plastic would curve but I don't know about the Midge's thick plywood.

As for being told I like ugly, if it's anything like girls they're usually more fun

[Edited on 6/7/16 by choc-ice]


ettore bugatti - 6/7/16 at 09:06 PM

Interesting plan about welding plastic sheets, you might not be the last to use that technique.

You can bend it with a heat gun too, so that offers potential for the scuttle. CAD should be able to generate some template so you can check the shape during bending.


choc-ice - 7/7/19 at 08:57 AM

Holy thread resurrection, Batman!

I've made some progress but it's been so incredibly slow that even if it was a month since the last post, you'd say I was a slacker.



Since my last post I've gathered some parts from real TCs to give it a head start in terms of shape and proportion. Someone suggested earlier that I use a metal TC scuttle with its complex double-hump shape instead of worrying about how to make it myself so I did this for some other parts too. Here's what I've found after looooong searches:

Fibreglass front wings - £100
Fibreglass rear wings - £75
Metal scuttle - £100
Fibreglass front apron - £30
Original radiator shell - £150

All these came off TCs that were bodged through the 1960s and 70s when they were cheap old cars and were now being properly restored. It might seem like a lot of expensive parts but metal front wings are £2200 a pair, rear wings are £1700 and the scuttle is £500, my costs are a lot less than a "real" one. A radiator shell? £1200!

I couldn't progress on the chassis with anything more than the rough idea I had before, unless I had a 1970s Midget to measure up the suspension components for. I kept an eye on eBay, Facebook and anywhere else I could think of for a Midget that was rusty but had its suspension parts. Even a set of complete front suspension parts is £300 because people use them on their Austin A35s. This was a bit pricey for my project which was definitely still in the planning stage.

After a while, this came up. Someone had used the parts they need, intended to use the shell for a hillclimb racer but changed their mind and now just wanted rid of it. Isn't it beautiful?



ok, it's not beautiful, but the price was free as long as it was removed before that weekend. Obviously the car was 100 miles away but that's what Shipley is for, so for a price of about £130 it was picked up and delivered to my house. This meant I could measure up the suspension units at my leisure and then design the chassis.



I went along to the kit car show at Stonleigh and had a look at some ladder chassis to get an idea of the size of box section I need. The real TC uses a channel section rather than box section, but it's about 75mm tall. After looking at several chassis from Reliant, through Cobra (both using 75mm tall box section which must make the Cobra a laugh with all that torque) and finally Marlin (the strongest of all at 100mm box section?) I settled on 75mm x 50mm box section with 3mm wall thickness.

I positioned them in the CAD over this drawing to get things in the right place



And this is it



Which allowed me to sketch in a ladder chassis picking up on the suspension points (mostly)



Back to the bodyshell, here's something that I didn't bank on - getting the shape right. I had factory drawings, I had a basic CAD model, I had a 1:24 model kit, they'd all overlay and be the same, right? I couldn't be more wrong!


choc-ice - 7/7/19 at 09:57 AM

I bought a book by Mike Sherrell called TCs Forever which is basically the restoration bible. It had loads of information about size and shape of the body tub which didn't match the factory drawings.



But that's ok, because the factory drawing of the bodyshell didn't match itself between the side view and the plan view!

Neither of them matched up with the CAD model I had, but that's not too surprising because getting the shape absolutely correct is proving to be very difficult. In the end I went for the TC's Forever drawing with just a hint of the factory drawing, because back then the "master" was what was being made in the factory, not what the drawing office thought was being made. As for drawing complex curves and tying up different views? There were about a million places that could go wrong and just one place it could go right.

I used the drawings to produce these curves in the CAD, which describe the curve of the bodyshell front to back, and how it curves under lower down the body tub. Then we'll fast forward over the checking, rechecking, putting it into the main assembly and checking again... The straight lines in blue are the major width and length dimensions that I was reasonably sure of, it also allowed me to transpose the parts from one assembly to another for checking.



From these curves I created (yeah right, the CAD created) the complex curve of the side of the tub



I'd spoken to a metal fabricator about chassis and he'd told me about laser cutting of tubes. It's no problem to mark and cut the chassis tubes myself, but he said if you want real accuracy on a chassis, like 0.1mm per cut, use something like this. It's hypnotic to watch.



This is the only way to cut intersecting round tubes without driving yourself crazy but because the machinery works so fast, it can be cost effective for square tubes too. It also gave me an idea of how to finally do the body shape that I needed instead of that tricky and expensive mucking around with shaving wood to shape.

I used the surface to assemble box section metal to, then to describe the way I needed it cut. Like this



I've spun the view around a bit so we're looking at the left side of the tub but from inside. There's a sill that gives the lower shape, a vertical (in one plane) post that's the door hinge at the back and then two longer pieces which are the door striker and the front of the body tub.

With the surface removed, the body assembly looks like this



It gives me plenty of weld area to the 50x75x3mm box section at the bottom and locates the 3 uprights I need with good accuracy. I can now add an upright which will give me the top seat belt anchor and horizontal pieces to run along the top of the rear wheelarch.

I'm still undecided on the bodyshell itself, I could use plywood, plastic or even sheet metal to do the tub.

I spent a while with a complete 1500 Midget and took some basic dimensions of the engine. If I use the engine, gearbox, suspension and steering as is planned here, I'll have no problem getting enough points to keep an age related plate.

As you can see, there's still an awful lot to do, but at least it's moving forwards a bit. Comments and help are welcome!


hughpinder - 10/7/19 at 12:27 PM

About 20 years ago my dad restored a TC. He was missing the front wings. By sheer change he was chatting to an 'old boy' in the pub one night who used to work in the factory hand making wings. He offered to make some for him - my dad turned up the next day to this random tatty shed, not expecting much, and found him just finishing the second one on the wheeling machine(for 150/pair). When asked how he measured the bits (since no plans or drawings were in evidence), he was told it was just by memory/eye. We fitted them when he got home and they fitted as well as anything else +-1/2" difference in the length/width of the body panels from one side of the car to the other seemed to be about the standard fit for anything!


dan8400 - 10/7/19 at 07:28 PM

How about fibreglass over plywood.

It’s a nice little series to watch if nothing else

https://m.youtube.com/watch?v=JJax6pqlEoI

Thanks
Dan


HowardB - 10/7/19 at 08:45 PM

quote:
Originally posted by coozer
Why not just build a Jaguar SS?

Saw this at Stoneleigh a few years ago and was very impressed....





oh - that is nice!