1936 Mercedes-Benz 540 K Cabriolet B - The Old Italeri Kit After Some Improvements * * * Plus Tutorial: Better Treads for Styrene Tires (complete)

[Dann Tier]

Masterpiece comes to mind.

[Plastheniker]

I think it would be a great service to a lot of us if you would consider posting a tutorial on the forums sharing your method of creating that tire tread.

I will try to start a tutorial here probably on Friday.

[misterNNL]

 

I will try to start a tutorial here probably on Friday.

 

I will try to start a tutorial here probably on Friday.

Outstanding!!

[Ack! Ack-ack!]

Another fantastic masterpiece from your workbench!

I am looking forward to the tutorial. I have several old Italeri car and truck kits with hard plastic tires.

 

[Eric Macleod]

This is absolutely spectacular.  I wish i had half the model building skill you have in one finger.

[Plastheniker]

Thanks again!

 

Another fantastic masterpiece from your workbench!

I am looking forward to the tutorial. I have several old Italeri car and truck kits with hard plastic tires.

 

You can find most of the information in German here:

http://www.wettringer-modellbauforum.de/forum/index.php?page=Thread&threadID=44033&highlight=

[Plastheniker]

Here comes the requested tutorial. Please give me an early response if anything is not understandable. Thanks!

 

 

 

 

I. The Problem

 

 

Today modelers expect vinyl or rubber tires in every car or truck kit. Nevertheless there are still kits with two-piece styrene tires. These kits are mostly (re-)releases from the fifties or sixties, but even Italeri (Testors) car and truck kits from the eighties and nineties had and sometimes still have styrene tires.

Most modelers hate styrene tires because for casting reasons these tires have no or only very faint treads. Moreover most of such treads gets lost after filling and sanding the gap between the two tire halves. As a consequence modelers usually try to replace styrene tires by vinyl/rubber tires from other kits.

 

IMO there are some very good reasons, however, to use styrene tires - provided you can give them acceptable treads:

• Sometimes there is a chemical reaction between vinyl/rubber tires and styrene rims that softens and finally destroys the rims (a notorious Italeri problem when they included vinyl tires in some kits in the eighties).

• After years or decades some hollow vinyl/rubber tires prove to be too flimsy to sustain the weight of the model. The tires become flat and never regain their original shape (a former RoG problem concerning some truck kits) .

• Some rubber compounds cannot sustain decades of exposure to daylight. While all four tires on one of my models came from the same cluster one tire dissolved completely while the other three tires, more or less covered, were not attacked (Casadio-Revival).

• A few vinyl tires keep their appearance but release an oily liquid, others stain cabinet boards irreversibly .

• Even if you have ample stocks of vinyl/rubber replacement tires very often the size required is missing. If this is the case there is no other choice than using the kit styrene tires.

• When converting or scratch building sometimes really exotic tire dimensions are needed. Opposite to vinyl/rubber tires styrene tires can be modified regarding width and rim diameter.

 

And in case you have to scratch build tires completely from styrene there remains the problem of how to make the tread.

 

 

II. My Solution

 

Actually my approach is rather obvious.

Basically I cut off the unusable tread from both halves of the two-piece styrene tire. I glue a styrene spacer ring between the two remaining tire flanks to restore the original tire width. The gap between the two tire flanks and the spacer ring is filled with a styrene strip from scribed styrene sheet.

 

 

This may seem quick and easy but unfortunately it isn't. Working accurately is essential and if you tend to miscalculate ...

 

III. Necessary Tools

 

Besides the basic tools owned by every modelers only a dial (or digital) caliper is indispensable because, as already said, precision makes or breaks the finished tire.

All other tools and devices mentioned below make it much easier and much faster to achieve a convincing result, but if necessary you can do without them.

 

 

IV. Preparing the Two Tire Halves

 

All remaining tire flanks must have the same thickness all around, otherwise more than slight differences make the finished tires look wobbly and problems when inserting the rim might occur.

 

• Therefore cutting with a rotary tool without support should be avoided, but if you prefer to rely on your steady hands mark the line on which you intend to cut with a narrow strip of tape

• Better results are achieved with a self-made construction that could be called "lying fretsaw" You saw here by moving the tire half and not the saw. You determine the height of the cut by adding or removing those plastic sheets seen on the right side.

• A similar self-made construction you could call " lying saw blade" works slightly faster. Here you determine the height of the cut by shimming the saw blade up with more or less washers.

• A converted small drill press with rotary tool and circular saw blade is the fastest and most exact way. By turning the vertical wing screw you can adjust the level of the saw blade by fractions of a millimeter. Watch out, you have only ten fingers!

 

 

V. Making the Spacer Ring

 

This is rather laborious because the spacer ring must have an exact outside diameter (remember the drawing above) and an exact inside diameter (= the rim diameter).

• In most cases I use rings cut from telescoping tubes. Usually it is necessary to shim the rings up with strips of styrene. The best way for cutting absolutely vertical rings of equal width from tubes is a manual full-size miter saw (stay away from the flimsy small plastic Dobson Miter Rite).  Originally meant for large pieces of material the surface of the "table" is often ribbed. Simply bolt on a piece of angle as I did. You will have to spend about 50 $, but you get a most versatile tool. I use mine almost daily.

• For large tires, f. e. truck tires, a full-size adjustable circle cutter can cut one-piece rings from thick styrene sheet. This one works perfectly.

 

 

 

To be continued:

 

VI. Making the Tread Strip

VII. Assembly

VIII. Painting the Finished Tires

IX. Inserting the Rim

[Plastheniker]

VI. Making the Tread Strip

 

There are three ways to make the tread strip:

• For the fast and easy way visit the model RR department of your LHS. Look for injection moulded N-gauge or Z-gauge styrene brickwork sheets. Cut off strips (after buying the sheets of course) and use them as the new tire tread. These are two examples

• Scribe any tread pattern into 1.0 mm styrene sheet using a steel ruler and a steel needle/reversed #11 blade. The result will always be more or less spotty but on the finished tire this is tolerable. The scribing procedure , however, is extremely painstaking and after several hours you wonder which part of your back hurts most. Again two examples

• A faster and much more accurate way of making individual tread patterns is the use of a full-size X-Y-table. This is my usual setup with a slowly-running electric drill and a slitting cutter. The treads of the Mercedes 540 K shown at the beginning of this thread was made this way.

 

 

VII. Assembly

 

Test fit before any gluing! If you are satisfied glue the tread strip onto the spacer ring. Instead of gluing this sub-assembly directly to the tire flanks and filling the two gaps consider to glue two additional very thin (0.5 or even 0.3mm thick) spacer rings with a significant smaller outside diameter between the tire flanks and the sub-assembly. This makes two nice additional grooves as seen on the pictures of the Mercedes 540 K and of the Auburn.

Since I never saw an adjustable circle cutter usable for very thin sheet I built my own many years ago. I works perfectly.

 

 

VIII. Painting the Finished Tires

 

A realistic painting is crucial.

First spray the complete tire flat anthracite. Trim the bristles of a wide brush (medium quality is sufficient) to max. 3mm. Drybrush the tire with a lighter anthracite mixture except the area close to the rim. Finally drybrush only the tread with a dark dirt colour. Don't overdo!

Usually drybrushing makes the tire shiny, then spray a final coat of flat clear.

 

 

 

IX. Inserting the Rim

 

Two-piece rims make inserting and applying glue easy.

For inserting one-piece rims cut off the inside rim flange, apply some glue, insert the rim and glue the rim flange back to the rim.

 

 

* * *

 

 

 

As said at the beginning: If anything is not understandable or seems incomplete , please ask!

 

[Spex84]

Spectacular! I love the grille treatment.

Eagerly waiting part 2 of the custom tire tread tutorial

[misterNNL]

Wow you certainly delivering a highly detailed tutorial. Thanks for investing the time and effort necessary to do this.

[PhilX]

Very interested in your wire wheels. More détails about them ?

Like you I like pre-war models and i've a lot of them to build (like your Bugatti, Alfa-Romeo, Mercedes, etc ...)

And for these models, I think you cannot avoid making your own wire wheels.

[Classicgas]

Now it just isnt right posting photos of a real car and saying it's your model! Seriously, that is beautiful!! How about some color pics, and engine pics?

[Ack! Ack-ack!]

Great tutorial! Thanks!

[GerN]

Excellent in all ways!  I completely agree about styrene tires - I often cast tires for my model cars, particularly to allow modifications.  And styrene or resin tires can be painted.

[Plastheniker]

Thanks for all replies!

 

Very interested in your wire wheels. More détails about them ?

Like you I like pre-war models and i've a lot of them to build (like your Bugatti, Alfa-Romeo, Mercedes, etc ...)

And for these models, I think you cannot avoid making your own wire wheels.

My detailed wire wheel tutorial can be found here:

 

Making real wire wheels in all scales

http://www.modelcarsmag.com/forums/index.php?showtopic=77554