With the steering system having caused more headaches than anticipated and research taking a long time, actual progress on the V8Mongrel has been very slow recently.  With a nice, temperate weather forecast, I decided to put down the books and get back into the garage.  There is still a lot to be done other than the steering, much of which can be accomplished without any need to consider the final steering solution.  The temperate weather is also better suited to working with composites, so the rear fender flares were a natural choice.  Having previously purchased the raw materials (which incidentally have a limited shelf life, providing even more motivation to work on this particular project) I could (theoretically at least) get to work without having to wait on anything.

There are posts in the exterior category where I have provided links and information regarding different methods of making fender flares.  I am not following one specific method, but amalgamating the knowledge I have gained and doing what I feel will work best for me.  So far I have created the very basic outline of the flare using insulating foam and blue painters tape.

I taped down a piece of foam in the front to act as a base.  I still have to figure out how to trim that leading edge. The foam is easy to work with, but can make a fluffy mess if cut too quickly or the cut edges are handled roughly.  Heating the knife blade makes for a cleaner cut, but if it is too hot, material close to the blade melts and can remove a lot more than the knife will when cold.

I plan to have the big, flat rear space be cut out and filled with mesh.  The reason for this is twofold.  First, I have seen it done on many professional cars, presumably to relieve pressure; thus another case where I am following the ‘when in doubt, copy the pros’ mantra.  Second, flat is a lot easier to make than curved.

After taking the first pictures, I added an extra support at the leading edge.  From the bottom of that extra piece to the bottom of the fender, I still have to figure out.

Not much to look at so far, but that took a couple of hours since it was my first shot and on the steepest part of the learning curve.

Torque Arm Link Construction

With the link made, it was time to get the connections done.  I managed to do the entire project with parts that were leftover from previous endeavors.

The chassis side pivot point for the link was made from a universal shock mount that was part of one of the many failed attempts at mounting either the front or rear shocks.  I think front, as it is painted red, but I cannot be sure.  And yes, that is the old, too short, link that is replaced in the entry shown at the top of this page.  The torque arm has two mounting holes in it, so no work was needed there.

There is the torque arm attached to the axle.  While it wasn’t in exactly the right spot at the time, it was close enough to make some cuts and locate where the link would go.

Unfortunately, the nut plate you see to the left of the cut is for the factory seatbelt latch, which is now unusable.  This plate also made cutting harder because it is (quite thankfully for those ever in a wreck) much thicker steel than the surrounding sheetmetal.  The view from the inside confirmed that I had made the cuts where needed.

The silver bar visible through the hole is the torque arm, and clearly visible is the mounting hole.  The black bar in the foreground is the seat mount.  I considered using that to mount the pivot, but decided against it because I didn’t want anything to compromise my ability to mount the seat safely.  I also, I don’t want any forces from the axle transmitted to the bar if I am in a crash.  Both the torque link and aluminum arm will be failure points before the seat mount, but better safe that sorry.

I’ll show how the link pivot gets attached to the chassis.  It is still in progress to some extent, so I don’t know when that will be exactly!

Part 1
Part 2
Part 3

The upper control arm mounts, which also ended up including the front shock mounts were a real challenge.  I made some mounts, found out they were wrong, and had to scrap them.  I cut out the factory strut towers for clearance and found out that they might have been useful for mounting the shocks.  I bought shocks only to find that they were too long to fit in the front of the car.

The previous posts have shown the process of putting together the mounts.  Unfortunately, the shock mounts were made during the camera failure time, so I have no pictures.  They are a combination of simple box tubing and an off-the-shelf circle track mount that was at the wrong angle to work without modification.

The parts were then welded up and given a coat of appliance epoxy.  Here is the result.

I would like to add some bracing to support the shock mount since it is kind of floating in space, but that will be later on.  This should suffice for now.

That leaves on the strut rod mount left, and the front suspension is done.

Nearly every sanctioning body requires a master cutoff switch – a single lever or button that will turn off the engine and isolate the battery from the rest of the electrical system.  While it can differ between sanctioning, many stipulate that the switch must be accessible by safety workers from outside the car and must act upon the positive circuit.

The only real complication involves an alternator.  Even with the power from the battery cut, if the engine is turning, the alternator will continue to supply unregulated voltage to the system.  This means that not only dies the switch not function as intended, but there is a risk of damage from voltage spikes.  The solution is a four post switch, which has the main circuit switched like every other, but also has an isolated circuit, activated by the same switch but getting direct battery power rather than feeding through the alternator.  These extra posts are for a circuit that will kill the engine.  I wired the ignition system power to the extra posts, and it works as intended.

What I came to realize was that with the switch accessible to the safety workers, it would likely be inaccessible to the driver.  I could put the switch near the driver side window, but all the power wires, the ignition system and the battery are on the other side.  Also, since in any sanctioned competition a window net will cover the driver side, a switch there might not be considered accessible from the outside.  Thus, the passenger side seemed the better choice, in spite of the driver access issue.

I still have to add the obligatory sticker that makes the switch location more easily known from the exterior.  However, it should be clear that the driver cannot reach the switch without climbing across the car.  Obviously when belted in, it just isn’t going to happen.  I decided that rather than add another switch, I would add a cable pull to the one already in place.

I used a universal parts-store sourced cable, originally purchased for the trunk release that I had section of leftover.  While it didn’t have a finished handle on either end, that didn’t seem like a huge hurdle to overcome.  The project would be a non-starter if there was not way to attach the cable to the switch, so that was step one.

A hole through the handle, a simple 10-32 Phillips head machine screw with a serrated face nut for extra security against loosening, then any unused portion of the screw cut flush with the nut and sanded smooth.  The cable is wrapped around the bolt, then pinched in place.  Pulling the other end of the cable is, by design, pulling the cable into the bolt.  Not too high tech, I will admit, but when it comes to an emergency use system, I am of the opinion that simplicity is a virtue.

Routing is accomplished with simple plastic cable clamps riveted in place.  The pull end would take the most work as everything would be fabricated from scratch.  I needed a bracket to hold everything near the driver and position the outer cable so that only the inner would move when the handle was pulled.  I needed a handle and way in which to attach the cable to it.  Finally, I needed to make sure the unit was the proper length and attach it.

The bracket was made from a three tabs I got from A&A Manufacturing.

3/16″ hole for use with rivets.  I added two more holes for strength when mounting, and made a duplicate for the underside.  This way the thicker metal plates sandwich the thin factory sheet metal and the rivets have strong material to grip.

With the base done, I took another of the same plates and bent it into a U shape in the vice.

That was done with a hammer, not a press or brake.  You don’t need special tools to do many things.

The parts were mocked up before welding just to make sure that there would be no problems with the rivet heads.  The hole in the vertical piece is for the cable to pass through.

This really isn’t my best welding work, to put it kindly.  The rods were damp and I was in too much of a rush.  The parts are held together properly, which is ultimately what matters, but I regret that it is so ugly.  The remedy was a nice thick coat of paint.

Spray on tool dip is a wonderful thing as not only does it cover the ugliness, but it also provides a nice, soft feel to the component; perfect for a part in the car’s interior.  I gave the backup plate a coat too so that it wouldn’t rust.

The handle is a universal lawn mower pull handle kit bought from my local Ace Hardware store then given a thick coat of red Plastic-Dip.  I put the pull string in a drawer for potential use later, then using the same bolted clamp method as on the switch, attached the cable to the metal insert inside the handle.  The holes the insert came with were designed for the pull string, so were much too large for the thin metal cable used in this project.

The handle end was finished by riveting the bracket in place, then adding the cable.  The two parts of the cable (inner and outer) were separated, the outer attached to the bracket, and then the inner snaked inside it.  The outer cable was secured to the bracket with a wing nut that I had in my bolt box that luckily had threads very close to the spiral of the outer cable.  The far side (not visible) has a crimp on connector to stop it from accidentally being pulled through the wrong way.  Even though there is little chance of that happening since the force is in the other direction, I like the added security.

That is the finished product.  I lubed the cable and tested it repeatedly.  Overall, it works nicely.  I found that the wing nut threads weren’t quite close enough and that with a really determined pull, the threads would slip and allow the outer cable to move.  I added some epoxy to area of the cable where the wing nut goes  and to the clamp on the other end just for extra piece of mind.  Total investment is under $10.  If you don’t have the leftover cable like I did, you might have to spend $20.  Still cheaper than another switch, not to mention running cables across the car to it.

I am starting to develop an appreciation for cables.  They are quite useful.

Part 1
Part 2

Next up in the hierarchy of axle positioning was setting the lateral location.  This is determined by the panhard bar.  This is the easiest of all the rear suspension positioning  steps since it requires adjustment of just one suspension member and changes are linear as long as the panhard bar is level to the ground.

The bar attaches to the axle on the driver side.

And to the chassis on the passenger side.

Thus, shortening the bar moves the axle towards the passenger side.  The only possibility for a mistake comes from not having the bar level.  Since my chassis mount is on a slider and the axle mount is bolt on, allowing it be loosened and rotated around the tube to change the height at the other end, this is easily accomplished.

Yes, another circle track part.  It is a Howe Racing cast mount was bought used for less than $20 and does everything I need.

A level panhard bar is important because it minimizes side-to-side movement.  As the axle moves vertically, the panhard bar scribes an arc.  Any bar with one end fixed and one end moving will do this.  The longer the bar is, the less lateral movement there will be.

While length is a design criteria, angle is a setting.  If we take the arc of travel and continue it, we will end up with a circle.  At 90° from the plane of the axle, motion will be almost all lateral and very little vertical.  Conversely, the motion when the bar is level to the axle is mostly vertical.  I have tried to illustrate this below.

Hopefully you can see that an angled bar results in much greater lateral motion.  The astute amongst you will also have noticed that the angled setup also yields less lateral motion than the level bar when the axle moves downward.  If you know that your axle will only move one way, such as on a circle track car, you can use this to your advantage.

Also note that with a level panhard bar the axle moves to the right (passenger side when looking from the rear) in both compression (upward movement) and extension (downward movement).  This means that if the axle is centered in the car when the bar is level, all movement will put it off-center.  A compromise is to set the neutral position slightly to the driver side.  This cause the axle to move towards center at first, and then proceed more to the passenger side.

How much static offset is the right amount?  That requires trigonometry and my memories of that particular subject are strangely dominated by images of the rather well developed blond who I was fortunate enough to sit next to in class, and very little math.  So I guessed and set it at just under ¼”.

Next up, pinion angle.

Part 1
Part 2
Part 3

While the air pan may not be how I want and ultimately determined that it is not fit for use on the car, that doesn’t mean that it is useless.  More so than an air pan, this has been a learning experience and the learning isn’t complete until every step in the project is done.

The next part of the process was to cut the air pan so it can be attached to air cleaner base.  The plan is to use rivets to attach it to the underside of the air cleaner lip.

The other side of this face is the surface on which the air filter sits, so the rivets head will face up to allow the filter to seal properly.  Since the filter has a rubber body, it should conform to a small surface imperfection such as rivet head.  If not, well, I’ll cross that bridge when I come to it.

I made a centering mark and then placed the air cleaner housing in the proper location in order to trace a circle around it.

Of course, that is the outer diameter, which were I to cut around, would leave no lip in the fiberglass to attach to the air cleaner.  The cleaner base would fall right through.

The solution is to measure the width of the lip on the air cleaner base and measure inwards from the circle drawn on the fiberglass in a number of places.  Connect the dots and you get the above.  It doesn’t have to be perfect since it is just a guide for a rough cut that will need to be finished after the cutting is complete.

Lesson 4 – A wide tipped marker works better to mark GRP than the pencil tip Sharpie.

Time to cut, but first:

Important note:
Cutting fiberglass creates a lot of dust.  That dust is hazardous to your health.  Wear a good dust mask.  The first time I worked with fiberglass I didn’t and by the end of day, I was coughing up little specs of blood.  Wear eye protection. I have had fiberglass in my eye and it was one of the single most painful events of my life.  Look online for a picture of fiberglass under a microscope and you will understand why.  Learn from my experiences and protect yourself.

I tried to use hand tools to cut the fiberglass to minimize dust production and spread, but found nothing that worked for this part of the project.  On the edges, a hand hacksaw and high leverage metal snips worked well, but neither of these work well cutting a hole out of a panel.  So I went to the Dremel with a drill bit in it.

Lesson 5 – Start on a slow speed with the Dremel as high speed will melt the GRP.

While cutting I could feel the bubbles as the cut rate would suddenly speed up.  I am still looking into the solution to that, but I am now convinced that it is a problem that must be completely rectified before I continue.

Only step left is to make sure things line up properly.

Not too bad for an experiment.  I am glad that I took it to the end as I found a potential problem.

There isn’t a lot of clearance around the neck for the PCV hose.  I will have to clamp the final air pan to the cleaner base before final riveting so that I can mock it up on the engine with the hose attached in order to be certain that it will clear.  A fiberglass edge will slice a rubber hose in no time, so the clearance will have to be generous.

The next fiberglassing installment might not be for some time as I have the research to complete, but I will report what I find out and my new game plan.  Back to metal for the time being.

Part 1
Part 2

Time to lay some glass!  With the preparations done it is finally time to lay some mat, mix some resin and make a part.  For this entry, there isn’t the usual level of detail I try to provide.  This is for two reasons.  One, the pot time of the resin (how long it takes to become gel) is such that in-progress pictures aren’t going to happen until I have someone with me to operate the camera while I work the fiberglass.  Two, I am still learning this process and I don’t want to post up what I do until I have finalized my own procedures.  This is why there are no resin to catalyst ratios, cloth weights, specific set times or other details.  I am not sure I have it right so I don’t want to make any suggestions until I feel more confident.

Step 1 – I laid out the mat dry to make sure that it wasn’t too small.  Too large is OK, but excessively so just gets in the way, so trimming it to only slightly oversize makes sense.

Lesson 1 – Mark the cloth so that you know which way to lay it when the time comes.

Step 2 – I mixed a batch of resin.  I made an extra large batch; larger than was calculated for the mass of the mat because I needed extra for step 3.

Lesson 2 – Have everything ready before you add the catalyst to the resin.  You want the entire pot time to work with, not waste it looking for a brush or your gloves.

Step 3 – I spread a layer of resin all over the mold.  In this case that was the aluminum foil.

Step 4 – I put the mat over the wet mold and tried to press it into the corners as best I could.  You will see later that I am not exactly an expert at this part.

Step 5 – I then wet down with resin the top side of the mat.  I am still developing my own application technique.  Getting the resin to be even can be a challenge.  This step used up the remained of the resin made in step 2.

Lesson 3 – Be gentle with the brush.  As the resin starts to thicken slightly it gets sticky and a hard brush technique will pull apart the mat pretty badly.

Step 6 – I added natural fiber reinforcements (mixing sticks), mixed up more resin and put down another layer.  This may have been a mistake as I think it generated too much heat, causing the bubbles you will see later.  Perhaps I should have let it dry first.

Here is the wet layup.

Step 7 – Next, I let it dry.  Took about one hour in the upper 80° temperatures of North Carolina in August.

Step 8 – I pulled it off the table and then removed any of the aluminum foil still hanging on.

Now time for the real analysis of the experiment.  This was a learning experience, so the bad parts are going to be more instructive than the good.  Here is the catalog of problems that I need to determine resolution of before continuing with more GRP projects.

Problem 1 – The aluminum tape didn’t release like the aluminum foil.

Problem 2 – The corners didn’t form properly.

Problem 3 – Bubbles.  Lots of bubbles.

Time for some research on how to fix each of these problems.  Although there are obviously some issues, I am still pleased with the progress I am making.  The aluminum foil mold release worked really well.  I am getting a much better handle on pot times.  My application technique has improved.  Overall, I am gaining skill and feel like I am not far from being able to tackle the fender flares.

Link to Part I

Next step in the experiment that is to become that air pan was to set up the mold.  Slightly more complex than a flat panel, the pan still wouldn’t require any other than straight lines.

First thing to do was make sure I had a flat surface.  Unfortunately, I didn’t do this first, as the pictures will show, but I did do it early enough so as not to impact the final product.

The wet lay up process will take place on a rolling metal work table I got free when an office building was cleaned out.  The metal top is not level like a machinist’s ruler, but it is certainly close enough for this project.  There were a couple of lumps in the surface that needed to be taken care of.

They look like someone drove nails into the top, but there is nothing on the underside indicating that to be the case.

Since I didn’t want to risk damage to other parts of the surface, I kept the power tools in the drawer and took the offending lumps down with a hand file.

Halfway done.

Finished.  Lots of dust needed to be cleaned off afterward, but the surface is now smooth enough for my purposes.

Important note:
I am doing this entire project in an attached, two-car garage and chose a rolling table for this step so it can go outside once I start using chemicals.  My sources tell me that the smell of polyester fiberglass resin can permeate food quite easily.  Furthermore, the dust from dry fiberglass mat and sanding the composite material is irritating to airways.  This is a job best done outside.

The pictures above show glimpses of the next couple of steps, but here is the process in greater detail.

After measuring the underside of the hood and the filter base, I put up fences that would make the perimeter lip when duplicated in GRP.

Just some steel tube I had laying around, held with welding magnets.  Nothing fancy.

Next, I sealed the corners with tape so that when I put down the aluminum foil, there would be a smoother radius.  Not sure if this will make any difference, but in metal working sharp edges are a weak point, so I just followed my old habits.

Again, nothing out of the ordinary, just standard blue painters tape.

All of this was just the base for the aluminum foil that would be the surface against which the fiberglass would be laid up.  This is the same method as used by the guys on Muscle Car.

The only thing I did differently than the guys on TV was to not glue the foil in place.  Since they were using a disposable foam mold, that made sense for them, but since I want to keep this table and use it again, I just taped the edges down and sealed the seams with aluminum tape.

Here is the approximate location of the air filter housing on the mold.

All set.  Up next, time to lay some glass.

Since the car now has wheels, the need for fender flares has become very obvious.  I am not ready to dive right in and start with such a big composites project, so I have decided to start small.  I have previously made some flat fiberglass panels for purposes such as an undercar splash shield, but that allowed me to make it extra large and then cut to shape.  With the fender flares, I won’t have the luxury of avoiding bad areas, and I will have to follow curves, raising the difficulty level considerably.

I brushed up on my GRP (Glass Reinforced Plastic, aka fiberglass) knowledge by reviewing the resources I posted over a year ago.  Once I felt like I was up to speed, I looked for a good starter project.  Having gone through all the trouble of making a cowl induction system, I decided that having the air filter sit open to the engine bay made no sense.  Cold air makes any engine run better and provides more horsepower, so an airbox of sorts makes sense as a functional project.

I wasn’t sure that I could do a full box, but since I didn’t want to do another flat panel project a flat pan was out of the question.   I decided that an airpan with a lip around the edge would provide both good practice and function.  Something like this, but in GRP.

I would need a way to seal the pan to the underside of the hood; a function performed by the rubber door seal material in the picture above.  While cowl induction is supposed to provide a steady stream of cool air to the engine, I am still not confident that a rubber seal like that would last under the hood.  Perhaps in some applications, but I have very little room and precious few escape paths for heat, so I am going err on the side of caution.

I found that Moroso sells air pan kits for certain carburetor combinations, and that if you read the fine print, the fire retardant foam is available separately as part number 97070.  At just $12.95 from Summit Racing, I decided to pick up two boxes worth.  The beauty of the foam is that not only am I going to be using it for what is designed for (shocking, I know) but it will easily conform to the underside of the hood, which, because of strengthening ribs, is far from flat.

For materials, I will be using chopped strand mat (CSM).  The one square yard bag made by Bondo and sold in nearly all autoparts stores.  I don’t even know the weight, but I assume it 1½oz/ft².  The resin is polyester and from Elmers.  I got that at Lowes Home Improvement.  Once I feel like I have a handle on the process, I am going to find an online supplier that I can use to order in bulk to save money as buying piecemeal is never cost effective.

I will be using the aluminum foil method I saw on the Muscle Car TV show instead of a chemical release agent.  It has served me well in my flat panel trials, is cheap, available, and about impossible to mess up.  Since I don’t have a part to copy, I will be making a box without a top to serve as my mold.  Nothing fancy, this is about the learning experience more than anything else.

Hopefully I will end up with a usable part and the skill set needed to flare the fenders.

The first step in positioning the rear axle is done – fore aft location.

The wheel is still slightly towards the rear of the wheel arch at neutral position.  This is because at neutral position, the rear trailing arm is level.  Any travel will cause the axle to travel on an arc that brings it closer to the front edge of the fender.  I tried to compensate for this by leaving the axle a little towards the rear.

I had to slightly shorten the rear trailing arms to reach this position.  Since they are aluminum hex tap tubes, it was easy to do.