Brake & Clutch pipes - Pt 1

Finally made a start on brake pipes also realising that I need to run the clutch pipe as well. The clutch line is going to follow the line for the front brake pipes only extending past the nearside connection approximately half way down the chassis to where the clutch slave will be mounted. There will be a flexible hose from the rigid mounted clutch pipe to the slave.

I've made a start where suggested in the Gen II manual that being the offside front tee position. Due to the weather I was not able to roll the body outside as it is pouring with rain so I have bent the pipes and positioned the tee where I want it and will drill and fasten later when I can get better access to the chassis.

I spent quite a bit of time practicing both bending the pipe and creating the necessary flares. I can now get a pretty decent flare so am happy to start. I also made a couple of aids for both bending and cutting to length of the pipe. This saved a lot of stress when I was measuring out.

Jigs

The photo above shows the jigs I made to aid in correct fabrication with the flares in their respective nuts. I could then screw the nuts on and mark the new pipe at the back of the nut and then add the required length to allow for the specific flare that was needed. Single flare needed and additional 3mm from the end of the finished flare and the double needed 4mm. On the bent pipe you can just see two lines around the pipe these correspond to two alignment marks on my small pipe bender. It just makes things neater and more consistent. I am a bit of a stickler for the way I want my pipes to look. Only time will tell.

Front offside (unbolted!)

Rear nearside from flex to tee (clips to add min 200mm apart)

That's pretty much where I'm up to so far. I'm going to be looking for some more pipe clips over the weekend so as soon as I've got these I can continue.

I'm off to Stoneleigh on Monday, can't wait. Collecting  some bits from AK and my screen from Brasscraft. Lets hope the weather is good for all of the Bank Holiday weekend.

Fuel tank Installation

I have now moved on to install the stainless fuel tank from AK and a very nice part it is too. I've spent quite a lot of time reading various blogs etc. on how best to fit the tank ranging from drilling right through the chassis and welding in studs to straps that go under the tank and are fastened on top of the chassis. These are all great ideas but I have decided to go a different route.

On the AK Gen III chassis I believe that the tubing section has reduced from 3mm thick to 2mm thick (please correct if wrong but I'm going to be safe rather than sorry!). I would have been concerned simply tapping into 3mm thick with an 8mm thread which has a 1.25mm pitch doesn't leave many threads in the chassis tube. I have been known to be a little heavy handed when tightening up the screws so was worried about stripping a thread or two.

My solution was to make 5 off 3mm thk x 25mm wide stainless straps that go over the 5 mounting lugs welded to the tank. Rather than bolt through the luge and bolt directly into the chassis I have 2 bolts, one either side of the mounting lugs. These screw into M6 steel rivnuts.

I carefully offered up the fuel tank into the chassis, positioned it with an equal gap all round and marked the position each of the 5 mounting lugs onto tape that I have stuck on the chassis.

When all was suitably marked the tank was removed and the drilling process began. I had made a small drilling jig which I clamped to the chassis in the correct position and then initially drilled through with a 4mm drill followed by a cone drill easing out to the correct diameter. The cone drill was very much easier than using a much larger diameter drill in thin steel tube.

The only problem I had was that as soon as the 4mm drill broke through the chassis wall it snapped!!!! However, I was able to remove the broken part with pliers so no harm done. This would have been OK, I never break drills I thought to myself as the next one broke!!!. Chassis 2 me nil! The second drill end stayed inside the chassis and rang like a bell. This had to come out so I continued opening up the holes to 8.9mm (for the M6 rivnuts) and then used a combination of Henry the hoover, to suck out most of the drilling's and then a small powerful magnet on a string to get the broken drill bit out. This meant lowering the rear of the chassis and thumping the chassis with a rubber mallet to slowly make the broken drill migrate to the larger hole. 40 minutes of frustration and then joy as the broken bit attached to the magnet and came out the hole.

New plan was needed. I decided to use the jig only to spot the holes part way through then remove the jig and carefully finish. This generally took a little longer but gave much better results with no frustration.

The picture on the left shows the tank offered up with the lug located between the 2 rivnuts. The picture on the right shows it fully clamped up and nice and secure. In actual fact the strap evenly distributes the clamping load over the whole lug rather than just one bolt in the middle.

As you can see the tank in now installed. Not a permanent fix yet as I need to add sound deadening sheet to the large flat areas of the tank as it rings like the proverbial bell. Also I need to waxoyl the drilled chassis tubes. The 10 off  M6 screws will then be thread locked which will also seal the threads.

Only thing left to do is to add an earth strap from the tank to the chassis. I'll think about that later.

Next job is the brake pipes and fuel line.

Looking forward to the Bank holiday weekend as it is Stoneleigh Kit Car Show and I have lots of bits to collect. Lets hope for better weather this year than last.

Brake Calipers and Flexible Hoses

Now that the suspension is completely finished I thought it best to assembly all the brake calipers and flexible hoses, starting at the front.

As the eagle eyed will notice I have changed the calipers to yellow. Not to everyone's taste but I like them just fine. It took four coats of Por15 caliper paint to get the finish I was after. Not the easiest paint to use but well worth the effort. This took quite a while to do. Do be careful to paint in a well ventilated area as the fumes are toxic. I left these to harden for several weeks. The colour darkens very slightly as it dries.

OK then onto assembly. After doing a trial assembly of all the parts, lubricating the necessary areas with Molykote 111 silicone grease the caliper was then bolted, torqued and finally lock-wired in position (sorry no photos of the lock-wiring!). I did this as a complete carrier assembly as I did not want to undo the pins that allow the sliding parts and pads to be assembled after. It worked OK.

When that was completed I moved onto fitting the flexible hoses as instructed in the manual. Before you fully tighten up the banjo move the assembly through its full articulation to make sure that the hose is not pulled and does not kink either. When satisfied carefully tighten but do not over do it else you will damage the copper seals. (also don't forget to add them either!)

One thing I did have to do was to remove all paint under bolt heads. If I had thought a little harder before painting I would have saved myself a lot of work in cleaning the necessary areas. Still you learn as you go along.

Onto the rear calipers now. The process was similar apart from being able to attach the caliper carrier on its own. This was much easier and gave much more access when lock-wiring. For the eagle eyed the flexible hose in only connected at the banjo end. It is adjusted later when I fix it to the bracket on the chassis rail.

Now all completed. I must say that this has all gone well so far. Not easy but very rewarding and at last I feel that I am making some serious progress.

Well that's pretty much it for now. Just starting to mount the fuel tank and think about the brake, fuel and clutch lines. Sorry it's taken so long and I hope that it won't be so long till next time (famous last words!!)

Handbrake Mech - Pt 1

One thing I can't stand is loose/sloppy mechanisms, they are just asking for trouble (well that's my opinion and I'm sticking by it). I spent quite a while thinking about the chassis mounted part of the handbrake mechanism and wanted it to be both very securely fitted and positive in operation. I started by getting all the parts laid out to see what's what and get the assembly sorted in my mind. Needed to have a look through several other blogs to make sure I had the bits all the right way up. Don't forget to check all holes for powder coat and remove as necessary. I found an 8mm reamer worked great.

When satisfied I loosely assembled it all to see what I needed to do to meet my requirements. For the main pivot I have opted to cut down a longer screw into a stud and rigidly mount it to the bracket on the chassis using a standard nut and a nyloc on the bottom. They were both then tightened very tightly and thread locked as well. This gave a very sturdy pivot to start with.

On the pivot arm I used a similar process in cutting down a longer screw to make a stud and tightly secure again with a couple of nuts and thread-lock. This would become the pivot for the bar that the two cables attach.

Rather than just metal washers I opted to use some flat bearing thrust washers, one either side of each of the arms. This gives a very smooth operation without requiring additional lubricant, even water lubricates these bearings but dry is just fine.

I attached the two cables to the small arm but used shorter clevis pins as those provided were longer than I wanted. With the aid of a washer under the split pin all the slack was removed although all is still able to rotate freely without binding up anywhere throughout its travel. I used copper slip on the clevis pins to help keep them free as well.

All assembled and I am really pleased with its operation. If I ever do this again I will probably turn up a couple of pillars rather than have threads running in side holes. That would last much better although in reality this will not get used that much anyway.

Rear Suspension - Pt 3 Coil over Dampers and Tie bars

Next parts was the fitting of the springs and dampers. This was to prove a little more time consuming than I had anticipated. Generally they would fit however there was no clearance between the top mount and the chassis meaning that when under load there was a serious risk of a metal to metal clash as there is compliance in the rubber bushes. I have some before and after photos.

Before... You can just see that there is a clash  between the top mount and the chassis. There must be good clearance in this area.

After... There is now ample clearance. It was necessary to add a shim to take up the clearance making a good snug fit for the steel bush. This meant that I could happily torque the bolts with no fear of distortion.

The last thing that needed to be done was a final torque up of all nuts and bolts to the correct specifications. I always leave these for a while before re-checking and then 'paint spotting' the nut and thread as confirmation that all is OK. (At least for now!)

Drivers side complete. Just need to secure the handbrake cable to
the tie bar to stop it waggling around.

This is my setup for setting the torque on the drive shaft nuts. I
was able to borrow the torque wrench from Southam Tyres. They
were really accommodating and helpful.

All complete.

Now onto the calipers and flexible hoses.

Rear Suspension - Pt 2 Lower arms and Rear Hubs

Now for the lower suspension arms. These both went on really well, just needed to add spacers to fill the gaps for bolting securely. These were loosely bolted for now as I want to ensure that the rubber suspension bushes are not clamped in the wrong position else they will wear our more quickly or in the worse case, tear.

I had a few issues when I came to locate the hub assemblies but only on the nearside. It was a choice of grinding and re-painting or spreading the gap a couple of millimeters as bracket had closed a little when welded. I took apart an old bearing puller and with the aid of a few nuts and a length of M12 studding came up with a spreader which has worked much better than feared.

Both rear hub assemblies now attached to the lower wishbone. Don't forget to add the handbrake cables else it can be a little fiddly to attach them later.

Sadly I forgot to take photos when I was setting up the camber and attaching the driveshaft's but needless to say this took quite a bit of measurement to get the correct angle on both sides. On the drivers side it was a doddle and required no changes but the nearside was a different matter. Originally there was a 3.5mm stepped spacer along with the tone-wheel. I needed a 6.5mm spacer as a total measurement., I do not like lots a thin shims so decided to remove the tone wheel and the stepped 3.5mm spacer and obtain a solid 6.5mm spacer as per the drives side. After finding the correct part number in the parts catalogue it was ordered from SNG Barrett, arriving a few days later. Using this spacer meant that the drive shaft is still perfectly located and concentric to the diff stub shaft. All the time whilst checking for the gap you have to remember to ensure that the hub is the allotted 150mm from the top of the chassis.

Just a couple of comments about when I was fitting the handbrake cables to the rear hubs. The spigot on the end of the cable was a little loose in the hub body. I added a bit of shrink sleeve which perfectly took up the gap and made it nice and snug.

Rear Suspension - Pt 1 Rear hub assembly

Its been a while but had a lot going on recently. Things have now quietened down a fair bit and although I have been fortunate enough to have some time continuing the build I've not had the time to update the blog, so here goes!!

So now that the differential is installed I can commence the rear suspension. The first thing I did was to assemble the rear hub carrier's for both sides. The photo's below show the parts and progress to completion of both hub carrier's.

Now with the handbrake shoe's & mechanism attached.
(I've protected the shoes from dirt and grease).

Now with the wheel hub inserted.

Finally both hubs assemblies are complete and ready for installation along with all their necessary parts.