Test Driving the TDR 427 Roadster

[LR3]

Assembly of the rear end and spindles completes the frame part of the chassis. In the instructions there is a detail on sheet (step) 7 to pay close attention to. The rear of the frame is at an angle and the lower A arm end needs to have the mounting hole enlarged slightly as the 0-80 bolt goes through at an angle. The arm goes between the two brackets.

Tim used a #54 drill for the brackets and just threaded the bolt right into the forward most bracket. I did it the hard way.

One of the nice things about this model is the mechanical assembly. This is another area where I had jumped into assembly before the instructions were available and I had mistakenly mounted the arm between the last bracket and the tube frame. Just another time it was nice to take something apart that is bolted instead of glued.

The flex brake lines are not part of the kit but I couldn't just leave the calipers hanging out there. Once the wheels and body are attached they will never be seen again.

Tim has helped me a number of times with explanations of the mechanics of this model. For instance: There are basically 3 sizes of bolts/nuts used in automotive applications. They are ½", 3/8", and ¼" bolts/nuts (in 1:1 scale). In 1/8th scale these equate to 000-120, 00-90 and 0-80. Due to availability we are substituting 1mm for the 000-120.

The TDR 427 Roadster chassis was designed to take 0-80 bolts at all major suspension locations. Two lengths of bolts are required to assemble the chassis, they are ½" long and ¾" long. Some cutting will be required on some bolts but by getting the two sizes this cutting will be minimized. Also, a decision has to be made about the type of head on the bolt (hex or Allen) and the material ( brass or steel). Brass might have to be nickel plated or blackened.

I stuck with hex head and found problems more than once due to lack of a ¾" length in hex. There are no 3/4" 0-80 hex bolts, only Allen head. There also were areas where an 0-80 wrench did not have room to seat a bolt. Allen head, at least in some places, might be the way to go.

Bolt vendors are www.scalemotorcars, www.mcmaster, www.jimorrisco and www.scalehardware. Although Scalehardware does not list them, he will nickel plate his brass 0-80 and 00-90 bolts free of charge when asked so he can supply all the hex head requirements plus wrenches to fit all.

Edited February 15, 2011 by LR3

[Ralph Henderson]

Hey Syd, I get some of my fasteners from...

Micro-fasteners

you might check there, as they do have 0-80 by 3/4 hex bolts listed, in brass...

Looks COOL!!

[LR3]

Step 9 of the instructions covers the initial assembly of the block. There will be two production engine offerings: a street version and a competition version. This version of the engine was done in the original RP material, the parts that will be cast in resin are in progress . The block, bell housing and transmission will be RP but the smaller parts will be resin. The block only needs sanding where there are machined surfaces. I lightly sanded the RP heads and inlet manifolds as reference pictures seem to show those castings have finer grain finish than the block. I sanded the pan and valve covers to a smooth surface. The quarter is for size comparison.

The drawing details what size bolts are required and the pilot holes are indicated on the parts. Mating holes always line up perfectly from the CAD drawings so individual parts can be drilled knowing the bolts will fit when the parts are assembled. But if you sand too aggressively as I did on the front of the block you can always drill through the mating part as a pattern.

Most of the surfaces that require drilling will have an opposing surface for a base making it easy to drill bolt holes but the competition manifold has the carburetor mounts canted slightly requiring the manifold to be tilted a bit.

These are the pan, manifold and valve covers for the competition engine.

I have just placed the parts on the block for photos as I want to show how each will look. When I finish with the carburetors I will bolt the engine assembly together in the street version.

[LR3]

Not being a mechanic I forgot all about spark plugs until I found the next step included the distributor. I looked back at the head and found there were dimples cast in to show where to drill for spark plugs. Be sure to accomplish this before attaching the head as it is difficult to drill them after assembly. The plugs should reside at about 35 degrees or so based on a reference photo.

The hole size is not specified because 1/8 after market plugs have different base sizes depending on the vendor.

[LR3]

Step 10 adds the manifold, distributor and carburetor to the block. If the manifold is being bolted down instead of glued down, be sure to bolt the manifold before attaching the carburetor and distributor. Something I forgot to do while dealing with two different type assemblies.

I added brass fuel inlet blocking bolts, distributor wire boots and throttle linkage (the boots and rod end are from RB Motion.)

The fuel line to the carburetor distribution will be flex (the AN fittings are from RB motion, the elbow and T fittings are just styrene tube.)

The competition manifold features extremely detailed Weber carburetors. I don't have the talent yet to work out the fuel distribution or throttle linkage at this time.

Here is a reference picture of a Weber layout.

[Darin Bastedo]

Which competition 427 Cobra had webers? the only 427 Cobra I've ever seen in my reference albums with webers was the ex-bill cosby car that Brian Angliss rebuilt from spares. as far as I've been able to reserch there hasn't been a 427 Competition cobra raced with webers.

[ajwheels]

Legend has it that the TDR Roadster was configured with a variety of intake variations over time..............as for the 427 Cobra, it's competition history is sparce, for Shelby did not build enough of them to homologate the car, and as such could not run in the production classes.......and it was just not competitive elsewhere.......

[LR3]

Steps 11, 12 and 13 add the rest of the engine components. There will be a remote oil filter added shortly. There will also be an option for an oil cooler. If the cooler is desired one oil line will go to the cooler first, if no cooler is desired both lines will go straight to the filter. A V belt is in the works to replace the black tape simulating a belt.

[DaytonaTim]

Which competition 427 Cobra had webers? the only 427 Cobra I've ever seen in my reference albums with webers was the ex-bill cosby car that Brian Angliss rebuilt from spares. as far as I've been able to reserch there hasn't been a 427 Competition cobra raced with webers.

Also, remember that his engine will be offered separately from the 427 Roadster Kit. So those of you that want to drop this engine into you Deuce or T can do so. That is one of the things we strive for here at TDR. Gone are the days of having to kit bash your stash of model cars. Now think of it more as a 1/8 scale buffet.....you go up and select exactly what parts you want!!

[Carmikeman]

yep, gotta get me one of those engines. gotta Big Duece just screaming for one. very nice stuff!!!

[comp1839]

the TDR 427 roadster is off the charts guys! the chassis/ drivetrain details are just fantastic. the 427 will add another warhead to the TDR arsenal of engines. kudos to the creators and the assembler. very fine job!

[LR3]

Steps 14 and 15 assemble the bell housing/transmission and starter. The transmission mount has an offset. Be sure the holes in the bottom of the mount are facing forward.

Edited March 22, 2011 by LR3

[LR3]

Step 16 mates the transmission/bell housing to the motor and adds the exhaust manifold. This is also a good time to add finishing details like the wiring and transmission arms.

[Iron Fist]

awesome

[LR3]

Steps 17 and 18 are used to install the radiator and drive train then check the assemblies for fit before starting on the sheet metal. The engine is not permanently mounted at this time; just positioned to be sure there are appropriate clearances. It is said the fit between the sheet metal and engine is very tight and further adjustments might be needed later.

[LR3]

The sheet metal panels are thin aluminum allowing them to be easily bent and shaped. Use care when cleaning or bending the aluminum as it can be easily scratched. The panels can be cleaned with paint thinner or mineral spirits. Be aware that while cleaning if your cleaning cloth accidentally catches an edge or corner it will bend the material. Accidental bends are almost impossible to remove completely.

Key tools are a pair of duck billed pliers, a door hinge, metal ruler, x-acto knife or scribe, small vice or C clamps, pencil and possibly a triangle and protractor to help visualize angles by drawing them out. If confused about the angles the patterns could be transferred to thin card stock and a mock-up made before bending the aluminum. The door hinge acts as a poor man's brake held either in the vise or C clamps. Masking tape or similar on the surface of the pliers and vice jaws will help prevent scratching or marring.

The drawings show where to scribe bend lines and the angle of the bend. The arrows on the assembly sheet indicate the direction of the bend where there might be confusion. Generally bends will be 90 degrees in the obvious direction. The scribe line must be on the backside of a bend. Scribe lightly as a deep cut might break the material during the bending process. The scribed line produces a clean sharp bend edge. If a mistake is made and it is required to scribe the other side for the same line, the odds are the material will break away when bent.

One thing that is very important on making these bends is that you need to start with the internal bends first and work your way out to the edges. You need to bend the stair step in the pan before you bend the perimeter flanges. If you don't, the perimeter bends get in the way of making the stair step bends.

A second set of drawings is provided to cut out and use as a pattern to locate bend lines. Do not use high tack tape to affix the pattern to the aluminum. Scotch tape will bond too tightly to the metal, be very difficult to remove and in most cases leave a residue. If one feels the pattern would be more effective taped to the metal use low tack masking or blue painter's tape available at most hardware stores, tape sparingly. Actually it is best if the pattern is loose as some items require some lines on alternate sides depending on the bend direction. The bend lines for tabs could be drawn on the aluminum with a soft lead pencil before scribing. At times you may find it's beneficial to fold the paper pattern first to insure you know how the bends interact.

One thing that is really nice about this metal is that it can be easily cut with a pair of scissors. Since the modeler already has patterns included in the instruction manual, all they need to do if they damage a part, is to go to Lowes, or any hardware store that sells roofing materials, purchase some aluminum flashing that is about .007" thick and cut out a new part using scissor and/or and x-acto knife. I wont say it will be the easiest thing to do but I am sure it is possible.

Although a natural aluminum cockpit and trunk will look really nice, the real cars had the metal painted. To get the natural aluminum finish the modeler will have to work very carefully and make sure that all seams are completely closed up. If they decide to paint the metal then they should use some sort of "seam sealer" just like what the real cars would have had. I think this could be simulated by using water-soluble kids school glue or similar. The modeler could fill any cracks and voids with this, let it dry, and then paint the panels.

[stump]

This thing is amazing to watch coming together!

Couldn't agree more Mark. Fabulous to watch.

Syd, bet you'd be having no more fun even if you were building 1:1..................Seriously great work mate. Keep'em coming.

[LR3]

The plug wires were a jumble because I used telephone wire. Multi strand wire is too stiff and difficult to lay down. I finally found some single strand wire that would allow me to group the plug wires more realistically.

The red telephone wire was so stiff I would dislodge one end or the other when I tried to lay the wires together. The single strand wire was much more flexible.

[stump]

Yes Syd, the black leads look more realistic and suited to that much better.

They are probably closer to a "factory" look too. Coming along very nicely. (yes, I'm trying to save my penny's, but slow work...)

[GrandpaMcGurk]

Syd......the 427 looks great, try to save some of your enthusiasm for the body......you'll be getting your prototype soon.

If you could (being the body is fiberglass), perhaps pass a few basic (do's & don'ts) finishing tips on to the MCM members following this thread. I'm sure many haven't worked with a glass body before.

[LR3]

Don has a sense of humor saying "If you could (being the body is fiberglass), perhaps pass a few basic (do's & don'ts) finishing tips on to the members that have never worked with a glass body before." seeing as I have never dealt with either fiberglass or sheet metal before but I will have some tips from the Madd Fabricator to pass on.

As far as the sheet metal goes there has been a delay because when the prototype body met the prototype chassis (including sheet metal) there was some interference as one might expect with the body and chassis being developed in different locals. A new set of sheet metal was required and some body details were reworked. The new body is scheduled to arrive early next week and I will post pictures. The new sheet metal will arrive soon also.

Knowing there would be new sheet metal I chose to bend what I had as a learning process. Most of the parts were straightforward but a few are tricky and the bends need to be made in a certain sequence. I also learned it is prudent to tape parts together as you go rather than glue each part as you finish. All this will be covered as I work with and post about the new metal. The pictured parts have some gaps as the tape let some pieces move around when handled but by using tape you do get a feel for adjusting bend angles as sub-assemblies go together.

[GrandpaMcGurk]

I just had a chat with Syd regarding how to prep the fiberglass body for his TDR Roadster build, as he mentioned he (like many of you) may have never worked with a glass body before.

We've decided to do a mini tutorial at this point and pass along some tips, hopefully to give everyone a "step-up" as far as handling the finishing required to take the "mystery" out of the equation.

First of all, glass is not resin.......period.

TDR uses fiberglass for it's bodies because they are much lighter, they can be produced thinner than resin castings.

They can also be keep much closer to scale. The molds themselves are fiberglass as well...they don't break down the way rubber molds can and from one body to the next the castings remain constant.

Another benefit is that the bodies are laid up by hand one at a time...extra reinforcements can be added to corners etc. without the bodies becoming overweight, thick door stops as is often the case with resin.

Glass tends to be far more stable than resin in these (large scale) models.

The bodies are done with multiple layers of fiberglass cloth (fine, med. mesh) and random mat.

Pinholes and hidden voids are all but eliminated...if we happen to fine a flaw it is repaired before shipment or the body is trashed....TDR nor the Madd Fabricator sells seconds as finished castings.

One more interesting point is that bodies can be laid up in sections...for instance....if someone really messed up a fender.....it could be laid up as a "partial" without having to replace the entire body.

The only draw back to glass as far as TDR is concerned is that being laid up one at a time they require a little more time to produce than pouring resin.

Anyway, enough chatter....Syd will post some pics of the prototype body he received, give you his impressions and we'll dig into it from there.

Being unfamiliar with glass, Syd will be learning as he goes and sharing his hands on experience with the rest of you members.......so if you've been reluctant to give a glass body a try, follow along as Syd tackles his. He will be able to point out the "beginners" questions that TDR or the Madd Fabricator don't think about. We'll answer them as they pop up. If any of you members have questions about the glass please feel free to ask in this thread....we'll do our best to shed some light on them.....back to Syd.

Edited April 7, 2011 by GrandpaMcGurk

[LR3]

The fiberglass body arrived today! I have no experience with fiberglass so this will be a learning process. Hope I can keep the body looking this good when I have finished! The fiberglass finish is very smooth and true. There are no ripples on the surface as you can tell from the light reflection lines. The body is very lightweight and stiff. There will be a minimum of sanding required except where the panels are cut out. So far the kit consists of the body, hood, trunk, doors and their insides; the light bezels, lenses, etc, will follow later.

I see no areas requiring putty. Looks like the only work to be done is to sand the front and back mold lines (barely visible), cut out the openings and prime for color.

The 427 body compared to a Deuce.

[Darin Bastedo]

This build looks very impressive, as is the kit. I'm a huge fan of this so far, but there are a couple of things you might want to correct at this stage.

The Foot boxes and spare tire well on these cars were made of fiberglass not aluminium. The difference will stick out like a sore thumb to those who know these cars well. here is a shot of the footwells of CSX3345 during it's restoration.

Here is a shot of the trunk of CSX3111 one of the most original 427 Street Cobras out there.

Notice that the footwells are in white gel coat and the the tire well in black. Also of note ere the two fiberglass bulges in the rear of the trunk. these are to clear the under car exhaust system in the street cars.

[LR3]

Thanks for that information. When I paint the final sheet metal I will paint the foot boxes accordingly and not paint the upper sides of the trunk.