159 replies to this topic

[Jean-Michel Piot]

I'm starting today a loooooonnnnnnng topic where I will describe the whole process I use when restoring Cox models.

As I am currently restoring several Chaparral cars, there will be pictures of 2As, 2Ds, and 2Es.

OK, let's start...



Start is not always when you get the car. If you buy on eBay rather than at a swap meet, you have to worry about the protection for shipment. This is even more important when the model is not totally assembled or with parts that came apart.

Recently I saw a very good 2A, with only few parts that were assembled. The clear parts, which are very fragile and which are very important for the final result (glue can ruin the general aspect), were notably untouched.

Same for a 2D I bought few month ago, where only the two halves of the roof air duct had been glued together.

I had an experience with a former 2D that could have been a nightmare. Fortunately I simply had to polish the clear parts. Now I always ask the seller to wrap the separate parts, as this lowers the risk of breakage during shipment.

Here is the 2D I received with no internal protection in the box:



Fortunately nothing was broken and after a polish, as already said, everything was OK.

Now I always propose that the time taken for this service be remunerated. Some sellers add few USD, others don't but since I asked, special care has always been taken by sellers. Caution can also consist in not sending unuseful heavy parts in a lot or "dangerous" ones, like cement tubes.

Here are some excellent buys (OK, I admit the first one was, I mean, excellent because it was sent with proper protection and the car in in very good if not perfect condition):













But examples of unbuilt cars are pretty rare. The most encountered case is the one of cars that have been assembled and generally painted.

The first step is then to disassemble and remove the paint.

For disassembling, I first try with purely mechanical action.





Some times, when cementing is rather strong but without an excess of glue, using a modeller knife will allow to cut the contact zone.





If parts do not come apart directly this way with little effort (take care not to break the plastic), I also put on a little white spirit with a paint brush. It helps to separate the parts but beware not to leave the white spirit on too long. A few seconds should be enough.

Once the parts are disassembled, I wipe the white spirit or wash with soapy water.























Unfortunately, some times you cannot separate the plastic parts and have to destroy some. Here is the case of those fuel caps imbedded in glue and painted:



To be removed with a Dremel or something similar.

(To be continued with the way to remove paint...)

[TSR]

Excellent advice.

[Jean-Michel Piot]

The paint will be removed using a brake fluid bath.

It's better not to leave the parts too long in the bath, especially for the structural parts such as the body and interior.

Then I help with sandpaper and a toothbrush.

After a cleaning in soapy water I get rid of the remaining paint with an X-Acto with a gentle and patient action.



















Next step will be to have a close look at all the defects and...

- remove the remaining glue
- repare parts.

As you will see repairing will be a major part of the job. We will notably learn there how to repair wheels arches.

[yomama]

Great thread! I look forward to the progress.

[Quickcars]

Wow, glad to see this thread! I need all the help I can get. My 2D is pretty sad right now.

[Jean-Michel Piot]

As announced, before the reparation of parts itself, I want to show you the way I remove broken parts that are strongly glued.

Let's take the example of the 2E vertical rods that support the wing.

I first drill holes and thereafter use cutters.

Once the heart of the part is drilled and cut, you can try with white spirit and X-Acto.











Now, let's see how to remove cement, like on this interior:



To remove cement solely, you can use different rotating tools and/or files.





As with any rotating tools, it is very important to have variable speed. With some practice, you know what the correct speed will be for each tool, also depending of course of the nature of the material you are working on.

Especially for plastic, beware of too high speed that would make the plastic melt.

Here for instance, the speed is low:



The goal is to recreate the genuine surface or "re-surface".



Finally, I tried to remove the dash board from this 2E interior and... it worked...

But reparation is not only about removing parts, broken or not, and removing glue. It also deals with filling the holes, gluing broken parts, and adding material.

Now, we will see something quite spectacular:

Do you think the 2E body on the right can be saved?



The rear wheels arches are cut off, one front wing is badly damaged.

In order to repair such a body, you need another one. No, you will not make one body with two, you will create local silicone moulds with a two component silicone, the kind of which is generally used by dentists to take a 3D print.

First of all, you mix the two components in equal parts. Then you apply on the intact body on the very area you have to repair on the broken car and allow few minutes to dry.















You then have to scratch the inner surface with a knife for a stronger mechanical bond if need be.



Then put the mould on the broken car and pour the epoxy resin. Of course you have to apply the mould strongly to the body with your fingers to avoid resin leakage.













Once the resin is dry, you sand down the excess. Et voila!











Pretty smart, isn't it ?

It's easy to use (yes, I admit, you need another genuine body), quick to do, and the result is of course faithful to the original shape.

I used the same process for the two holes on the left side, and re-glued the rear support for chassis and here is the final result:





Next time I will show you more classic repairs with styrene and epoxy mastic. And adaptation of quality repro screens on a couple of 2Ds.

[Brad Korando]

Based upon what you have posted so far: I don't think that it is too early to thank you for what will surely be a fantastic tutorial on the restoration of vintage slot cars. Thanks so much for sharing your restoration techniques. I'm looking forward to reading the next installment.

Brad

[TSR]

Jean-Michel is one of the very best there is in our little world.

[Champion 507]

All I can say is WOW!

I will watch and learn from a master.

Restore on!!

[Prof. Fate]

Hi,

Just to chime in, I am having a blast watching this. I have done that repair by simply using a bit of plastic behind the arch as a support, then layering up the replacement, and sanding to shape, removing the back piece later. Or cutting it away and layering up sheet plastic and again filing to shape.

Not really a restoration the way I do it. Grin.

I was struck by a point, though. I was sort of charmed by the look of the red stripe and nose panel flare. Very "period".

We used to have, at the annual convention in the US, a "Cox Challenge". Some were pretty tatty. But it was fun to watch these period bits actually being raced! Is this restoration likely to be run or raced?

Prof.Fate

[Jean-Michel Piot]

When you do not have another car, the way you did, Prof. Fate, is the only method.

As for the use of all those cars:

Some belong to friends who asked me to restore their toys, others are for sale, a few will remain mine. I do not know about others but for sure my cars do run.

I use the first 2E I restored and presented here in another topic, just like all the other restored cars I have at home.

Don Siegel is the owner of a second 2E I restored (also seen here). I know that his will was to participate to vintage meetings with it.

[Quickcars]

Glad to hear that they will be raced!

Any spare 2D windscreens laying about???

[Jean-Michel Piot]

Have seen your PM. Still have to ask to my friend if he still has some. Will tell you.

[Quickcars]

Hi Jean Michel,

No PM since Sept 1st. Sorry if I missed it.

Thanks for asking for me.

[bosmeck]

The master.

I like the resin idea a lot - thanks, JM - looking forward to the rest.

[Jean-Michel Piot]

To Quickcars: Sorry Paul, I was confusing with another recent PM, not from you. For sure I will ask.

To Chris and all: you will have another episode during the weekend when I will have time for posting. Many thanks for the kind comments so far.

[Jean-Michel Piot]

OK, so we have seen a first way to repair wheel arches or important gaps in a body with resin.

But the most encountered ways to repair parts or bodies consist in using plasticard and/or bi-components epoxy mastic.

Be aware that putty is definitively not strong enough for a repairing use. Moreover, when drying the putty retracts a lot. At last, it makes the plastic melt a little.

This does not mean that putty is a bad product or that I don't use it. Simply its use (which will be detailed later on) must be reserved to surface treatment and must not be confused with the one of above listed products.

First, see the use of epoxy mastic.



On the above picture you notably see a standard, with red labelling, Milliput "Yellow/Grey". I prefer to use the "White/Grey" one which is thinner but I was short of it.

Two component epoxy mastic, such as the Tamiya one or a Milliput products or Andrea Sculp etc. shall preferably be applied with fingers and thereafter be sculpted with tools first put in water.

The wet tools will not stick to the mastic and will allow forming the good shape from the start, a process which is easier than try to sand down a product that becomes really hard when dry.

Here is the way I proceed:













I said that once dry the epoxy mastic is hard and it's better to sculpt it at first rather than work on it when dry. True but you may still sand down a little once dry if needed.

Gluing styrene elements is useful when you have to repair a missing part of the body, like the base of a seat that went with the pilot itself. To simplify the repair, first cut the damaged zone or file it, in order to have straight borders. This will simplify the work.





But apart from this quite straightforward use of styrene, more interesting is the use of the two above seen methods in a complementary mix.

Such is the case of a mixed repair for 2D bodies where the window frames had to be reconstituted because of a da maged edge and were the pillar between side screen and windscreen had been both broken and damaged.

First of all, the pillar elements have been glued. But this is not strong enough.





So I had to cut bands of thin plasticard and cement them along the pillar and along the damaged edges, on the interior side of course each time.

Here is the view from the inside, with yellow arrows for the sole example of an edge.



On the next picture, you can see that the gaps have been treated with epoxy mastic, an exception being the same frame window edge, still to be filled with mastic.



Once the band is cemented (wait at least one hour to allow it to dry and be strong) I use the plastic band as a support for epoxy mastic. I guess that this method is the one Prof. Fate was referring to earlier about repairing wheel arches.

On the following picture, you can see that the gaps in this edge are now filled with epoxy mastic. Same for another edge for the rear screen.



Once dry this will be very strong.

This is the sole way I know to save the car because the Cox body is really thin.

[Jairus]

Those are some very good tips, guys, and this thread, once complete, should be pinned to the top for easy reference.

I for one would like to see how he paints those marvelous driver figures.

[Jean-Michel Piot]

Jairus, I will show everything.

My goal is indeed to help people in their restoration projects.

Now, to revert to the repair means, they can also be used to strengthen the body at the areas that traditionally show some weakness, like the screw mountings for instance.

They can also be used to modify a body or enhance it.

Let's take the example of the 2A body.

After a primer coat on a first body I noticed that the separation line of the right front wing was not sharp enough, especially when compared to the left one or to pictures of the real car.

I thought it was a defect of this very body but, after a comparison with other bodies including a NOS one, I understood that it was a general problem.

So I decided to fix it :













Don't forget to sculpt with wet tools!

Once dry and after a sanding this should be OK.

I will try to post more later today.

[Phil Smith]

Interesting and impressive work, Jean-Michel! Thanks for sharing it with us.

[Quickcars]

Awesome write-up so far. This will be a great help to me as I try to resurrect these cars. The white car will be the basis for my project.

I certainly have my work cut out for me!

[Jean-Michel Piot]

We have seen the different methods I use for repairing the body or plastic parts. But I still have to show you how one can repair, replace, or recreate the screens.

First case: you have a not-too-bad screen, with only little glue on it and scratches that can be polished.

Here is the case of a 2A screen on to which the rear view mirror had been cemented with an excess of glue.



Once treated with 1200 grade sand paper, and thereafter with 2000 wet sand paper and at last polished with Tamiya compound it came like this:



Notice that I filed and polished the pins that are made for mounting. I will explain the reason why later on.

But this method has its limits. Should the excess of glue be too much, or the screen be broken or cracked, you have no other choice than replace it.

Here are pictures of the way I cut and file the transparent parts from a complete repro set made of 1mm thick styrene.

Do not use thin or cheap thermoforming plastic. You really need something as thick as the genuine parts.



















For the 2E, Classic Tin Toy Company makes excellent repro screens. They are not cheap but the quality is worth it. Besides, if you consider the value of a 2E nowadays and if you follow this tutorial to make a nice 2E, the investment is worthwhile. By the way, they also have the transparent tree for the Cox Cheetah. As for the Cox Dino screens and light covers, you will find excellent repros at Mid-America Raceway (Roger Schmitt).

Of course, you can also order from Classic Tin Toy a set of rear lights for your 2E, but you may also recreate them.

Here are three methods:

- First on, you can turn parts in aluminum, using your mini-drill.
- Second, you can do the same in clear plastic, taken from a model plastic tree. Beware not to turn too fast.
- Third, you can create a silicone mould and fill it up with Araldite cement.

Lets see the two last listed methods.

- Turning a transparent rod taken from a plastic tree:





You can even paint the part on the mini-drill, when rotating. It is easier this way.



- Now the other described method: Using a silicone mold with the 3D print of genuine parts.

I put Araldite in the holes and thereafter some aluminum powder, to enhance the light reflection. Of course this will also need some red varnish.













Please note that Cox 2Es are often seen with a little relief in the middle of rear lights. It is simply because of the way they created their plastic tree. It is due to the attachment of the part to the plastic tree and this embossment has to be removed. A genuine 2E rear light is flat.

Let's see now the case of the front lights transparent covers for the 2A. This is at the limit between repairs and modifications/enhancement.

I have two genuine intact sets of transparent parts and four cars.

After a test fitting, I considered that the genuine parts were not good enough to be kept and that the process for assembly of the nose and light covers had important drawbacks.

The original mounting would not be strong, and painting the nose without a visible seal between the front valence and body would be complicated.

And more than this, the thickness of transparent elements would not allow re-creating a realistic seal appearance with a line of paint on the interior side of the transparent cover.



I then decided to create four sets of brand new parts. As you will see later, this may also be useful for a Le Mans version of the 2D.

OK. Let's consider a different mounting process of the nose of the Cox 2A.

Once the nose is assembled (details in a future episode), I sculpted dies in styrene that will be applied on hot transparent sheets of polyester.

For this I simply use a candle in order to have a very local heat.

The pictures speak for themselves...

















Simple, though efficient. I did not take pictures of the adjustments; it is the same process as seen with the 2D repro parts.

I now have to do the same for the three other light covers for the four 2As I have.

Of course, one can use a more conventional thermoforming process. Once again, it's all about what I personally do.

Those individual parts will really look better than the genuine parts, especially once a line of paint is applied at the periphery.

Now, with a repaired body, screens, and transparent parts at their optimum, we have a good start on a proper Cox model.

Next, we have to take care of the chassis.

You will see this very soon.

[TSR]

Not bad for a mere amateur!

[Jean-Michel Piot]

Philippe, your adequate comment highlights the fact that I use very simple tools, so the restorations I do could be done by a lot of people here...

[TSR]

Jean-Michel, compared to most, you are a true artist. All here love to see your restoration tricks and to learn from them.