May 2018
4 May 2018 – My Stage 1 order from Ultima has finally arrived. It was quite a challenge to offload, as Hellmann Logistics sent a massive horse and trailer with 2 x 20ft containers on the back to my house. The truck had to park in the road, causing some havoc with traffic.
The next problem was that the container was sealed at the Ultima factory in the UK with some type of key-less padlocks, which means I had to fetch my Generator and an angle grinder to cut off the seals from the container. At least I know nothing was tampered with during shipment.
All the boxes were very nicely packed and protected. The chassis was covered in bubble wrap, strapped down with high quality tie downs and then covered with a ground sheet. All the boxes are numbered, so my next job will be to do a proper audit of all the parts in these boxes to make sure everything is accounted for.
I have read in some of the build diaries that it is important to audit all the parts when they arrive to make sure nothing is missing. A project like this can take a long time, and you don’t want to find that something is missing a year down the line, because then you don’t know where and when it went missing or who is at fault. At least this way when something goes missing, I can check against the audit to see if I did receive the parts.
As you can see in this picture, the 335 rear tyres for the Ultima are massive.
Finally I am ready to start building. I have left the chassis on the wooden blocks it was shipped with, as my Porsche Speedster body is still resting on the Dolly I made for the Ultima Chassis during the build.
As the manual indicated, I started with the real bulkhead panel. Thanks to Humble’s Youtube channel I got some tips on making the panel holes a bit easier to drill. I purchased a 1 x meter steel ruler and drilled 3.2mm holes every 30mm. After I measured and marked the bottom and top position lines for the rivet holes (10mm from the bottom and 19.5mm from the top) I just clamped the ruler in position, punched the holes and started drilling.
I purchased 20 x 3.2mm drill bits, as I read on some other blogs that it is possible to go through many drill bits on these panels.
The drilling was also made a bit easier with a high quality cordless drill.
After the drilling was done, I cleaned up all the aluminium filings and deburred all the holes to ensure I don’t scratch the chassis and ensure a flush fit.
Before I started drilling into the chassis, I made sure to cover parts of the chassis and roll bar with masking tape and bubble wrap to protect the powder coating.
After positioning, measuring and clamping the rear panel (Used a spirit level), I drilled a couple of holes to secure the panel with the provided skinpins that came with the bag of rivets from Ultima.
I finished drilling all the holes, and removed the panel again to trim the bottom of the panels as per the instructions to clear the welds for a flush fit.
I still need to drill the holes for the handbrake and Porsche 996/997 Gearbox cables, but I will leave that for another day as I don’t have the correct 32mm hole saw.
Up to this stage, work was approximately 4 hours.
5 May 2018: I followed similar procedures to start with the cockpit side panels, however the panels don’t fit without doing the correct cutouts, and in order to do the cutouts, you need to do a pre-fit. The only way to do this is to cut a template using cardboard. I used the same cardboard that the side panels were shipped with, so the cardboard was the correct length.
I used the same cardboard template for the left and right side, as the panels are identical dimensions for RHD drive cars.
I made cutouts on the top and bottom of the template, as I just turned the template around for the left and right sides.
I used a combination of an electric jigsaw and pneumatic dremel tool to make the cutouts. There are still a few adjustments to make to the panels and the holes still need to be drilled, but it was too late at night to use any power tools without waking up the family.
So far, day 1 took 11 hours, with 4 hours on the bulkhead panel and 7 hours for the side panels.
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6 May 2018: Continued working on the side panels, making more modifications to make them fit and then onto the marking and drilling. There are many holes to be drilled on these panels, so it is time consuming. After drilling the holes in the side panels, I fitted the panels to the chassis using the skin pins and started drilling the chassis holes. I always had the vacuum cleaner handy, sucking up the steel filings as I go to make sure I don’t scratch the paint, especially on the cockpit floor.
There are approximately 15 holes that cannot be drilled with a normal drill in the corners and difficult to reach areas. For these, I used a Dremel tool with a 90 degree drilling attachment which I bought from Builders Warehouse. I am hoping that I will only need a 90 degree drill for the 3mm holes, as the Dremel tool has a very small chuck which can only take the dremel bits and the small drillbits.
I also realised that the Dremel spins way too fast for drilling through the steel tubing and will destroy too many drill bits at that speed. I made some modifications to the 90 degree attachment so I can attach it to my Makita variable speed cordless drill.
After the drilling was done, I cleaned all the chassis holes with the deburring tool and sprayed some wax oil in the holes to prevent rust.
These side panels took another 11 hours, so a total of 18 hours have been spent on the side panels.
The total amount of working hours to this point has been 6 hours on the rear bulkhead panel, and 22 hours on the side panels.
Total time to this stage is 28 hours.
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8 May 2018: After getting the panels drilled, cut and fitted, the next job was to bend the top of the panels to form over the round tubing of the chassis. To prevent any damage to the paint on the chassis or accidentally breaking the panel pins, I decided to do this in my workshop, using wood panels and a rubber mallet. I used flat pieces of pine and a router to form the round edges with the same contour as the chassis tubes. I then clamped the panels to these pieces of wood using G-clamps with cardboard between not to damage the panels, even though they still had their protective film on.
I then started hammering along the edge of the panel, moving from one side to the other, slowly start bending the panel edge to form to the contour of the wood. It took about 5 iterations going across the panel to ensure it bends smoothly along the edge of the panel.
I did this with all three panels. When this was complete I did another test fit of all the panels to ensure a perfect fit. I then removed the protective plastic covering from the panels and used the deburring tool to remove the remaining aluminium filings on both sides of the panel. I also used the dremel tool with a small sanding attachment to take off any of the sharp edges on the panels, especially around the areas where I modified the panels to fit around the steering support, front roll hoop and dashboard supports.
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9-12 May: I have been working in the evenings to start with the carbon skinning process on the interior panels. This is quite a time consuming process, as you have to wait for the epoxy to dry between coats, but not wait until is is completely dry as the different coats need to chemically bond before it has completely cured. I started off with the rear lower bulkhead panel, then the two side panels.
I sourced all my carbon materials and Epoxy from AMT Composites, however I also did a full day course offered by them to refresh my knowledge and skills on working with composite materials. The course covered mold making, vacuum bagging, resin infusion and carbon prepreg.
I am using Ampreg 21 Epoxy in a 3:1 ratio with hardener and black epoxy pigment to get the base colour black before the 200 gram carbon fabric is laid down. Before doing this, I scuffed the panel with 80 grit sandpaper to ensure a good mechanical bond of the epoxy to the aluminium. The sanding dust was cleaned with thinners before I painted on the black epoxy coat.
After approximately 2 hours, the black epoxy is still tacky, but no longer wet to touch. At this time, I carefully put down my carbon weaved fabric, starting from one side of the panel, rubbing out any air bubbles in the process. After folding the fabric over the edges, I cut it to size and secured the fabric to the back of the panel using masking tape, making sure the fabric covers the edges everywhere so that there is no aluminium visible afterwards once the panels are mounted and ensured there are no air bubbles. This is quite difficult around the cutouts in the panels, as the fabric weave can disturb and fray easily. Once the fabric is down, I used SP115 UV resistant clear epoxy to wet out the fabric. This epoxy is more expensive, but ensures the carbon panels don’t go yellow over time from the sun. This is done with a normal brush, so the surface is quite uneven after the first coat. This is where patience comes in. If you try add a second coat while the fist coat is still wet, you risk making ugly streak marks on the 1st coat if is still in the gelling process. If you lay the coats too think, then you risk having bubbles or runs that are difficult to sand. As I am working on this in the evenings, I have to let the epoxy dry overnight, meaning that it will have cured the next day requiring some sanding to ensure a good mechanical bond on the next coat.
Below is the lower bulkhead panel after sanding the 1st coat.
Below is the lower bulkhead panel after laying down the second coat. The surface is much smoother already, but will require some more sanding starting with 400 grit paper. Once the panels are smooth and I haven’t gone through the epoxy anywhere, it means I no longer need additional coats of Epoxy. At this stage, the panels are then sanded with 800 grit, 1200 and finally 2000 grit before polishing them up using cutting paste and polishing paste using a variable speed circular polisher.
12 May: I am leaving the carbon work on the panels for the week nights as I cannot make too much noise after the family goes to bed, so my 1st job for Saturday was to work on the front bulkhead panel. Similar to the side panels, this required making 4 different cardboard templates to get the fit correct. On the 1st templates, I cut too much on the top around to chassis by the suspension mounts, so there would have been too much of a gap. This panel is quite tricky, as I struggled to get the panel in the tight space without scratching the paint, but I wanted to make sure it is a tight fit.
After getting the shape correct to fit around the tubes and welds, I marked the holes for the master cylinder bolts and drilled them to size. After fitting the panel, I marked the holes for the master cylinders using a permanent marker from inside the cockpit. I then used a 38mm hole saw to cut these holes to size.
I then marked all the rivet holes as before and started drilling. I also measured out where the hole needed to go in this panel for the steering column according to the build manual.
After fitting and drilling up the front bulkhead panel, I got some help to turn the chassis upside down in order to start working on the bottom floor panels. These panels are easy to fit, but now I understand what some of the other builders are complaining about. There really are lots of holes to drill on these panels. Before fitting these panels, I drilled 4 x 6.5mm holes in the battery tray for drainage and the two holes in the radiator panel in order to get to the bolts for the radiator mounts. At the same time, I also marked the cockpit and radiator double skin panel to make fitment easier later.
These panels took the rest of the day.
Total time working on panels is now 64 hours.
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13 May: Mothers Day. We did the family thing for the day, but I wanted to get the floor panels done and riveted to the chassis. I spent 3 hours in the morning to get the panels done before fitting. In the evening, I was ready to start laying down sealer and riveting the panels in place. I did not worry too much about scratches on these panels or to clean too much of the sealer when done as I plan to rubberise the bottom of the chassis anyway.
Total time now 70 hours, of which 14 hours have been carbon work.
14 May: I masked off the chassis in order to seal and protect the bottom of the car. I picked up 2 x litres of Plascon rubberising paint which is normally used to protect the loading bay of utility vehicles, so this should be tough enough to withstand the elements as well as help with some sound insulation underneath the car. Nobody will ever really look beneath the car, but I did not simply want to paint the stuff on with a brush, so used what I learned from an old friend who used to build speaker cabinets for the mobile industry. Instead of painting the cabinets, he used a sandblasting gun to spray the cabinets using thick roof paint combined with wood glue. This stuff is also very thick, so the same process should work on the rubberising paint as well.
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15 May: Once the chassis has been turned over and the panelling done, there is not much more to do while the chassis is upside down, so I decided to take a day’s leave in order to get the rubberising job complete so the chassis can be flipped over again. The 2 x litres of rubberising paint was enough to cover the bottom with 3 coats, approximately 1mm thick. Before I started with the spray job, I erected a temporary spray booth to protect the rest of the workshop from overspray. I also used the Sikaflex to seal around the cockpit area before the rubberising was done. While I was waiting for the coats to clear, I did some more carbon work on the panels.
As you can see, the sandblasting gun did work, and gives quite a nice splattered finish.
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16 May: Starting with the double skin panels, I cut the cockpit inner panel according to the build manual and bent the panel for the pedal area as indicated. I also bolted together the pedal set and drilled out the powder coating from holes in the pedal mounts, as this will be way more difficult to do once the double skin panel is fitted as it would be impossible to get a drill bit in once the panel is riveted down. I then positioned and marked the aluminium brackets for the sides and cross brace before drilling. This panel was not difficult to fit, however took some time as there are plenty of holes to be drilled and deburred.
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17-18 May: Next panel to be done was the radiator double skin as well as the radiator side panels. The manual does not explain this, however I feel it is best to do these at the same time and to drill and rivet them together. Again, a cardboard template was used for this panel to make fitment easier. I also drilled the 16mm holes for the radiator bobbins which I marked before the floor was fitted. Additional 2 x aluminium braces were installed towards the back of the panel for extra support. Once these panels were installed, I mounted the radiator bobbins and tightened them from below through the holes previously made in the floor pan. These holes will be covered with grommets later to ensure no water gets in, but will allow me to replace the bobbins if required.
I also cut and test fitted the battery tray panel. Before these panels can be mounted permanently, they also need to get skinned with Carbon Fibre. Since this process takes a long time due to the curing time of Epoxy, I had enough time to start fitting the radiator. For now, I decided to keep the cardboard protection on the radiator to protect the radiator fins from getting damaged.
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19 May: Since I am covering all the interior panels with carbon, I was unsure if I should leave the area around the pedals in bare aluminium or if I should lay some extra carbon down in the area. Since this is the only section in the cockpit that does not have a double skin, I eventually decided that the additional thickness and strength of the carbon might help with sound and stiffness on this panel. I created a cardboard template for the pedal area in order to cut the carbon fabric the correct size to fit around the pedals. For this, I used a layer of 400g frabric together with a layer of 200g. This should add about 0,8mm of thickness to the panel.
While waiting for Epoxy to cure, I opened the box with the front and rear wishbones. I started with the rear wishbones since the front wishbones can only be fitted after installing the front bulkhead panel. I am still busy with some carbon work on this panel.
The red urethane bushings are easy to fit by hand, but the bearings needed to be pressed in with a little persuasion. After applying the silicone grease to the bushings and bearings, I used a wooden bench vice to press the bearings into the bushes to avoid damaging the bushings.
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20 May: I started off doing more of the epoxy clear flow coats on all the carbon panels, then leaving them to cure. I then continued fitting the bushings and bearings for the front wishbones. Once they were all done, I started fitting the rear wishbones. To fit the bottom rear bushings was a bit more of a challenge, as the frame mounts were too tight for the bushings to fit. I also had to drill out some paint in order for the bolts to fit. I used a smaller bolt, washer and nut as a tool to open up the frame mounts by a small margin so I could fit the wishbones without using excessive force and potentially damaging the bushings.
I used a rubber mallet to gently persuade these wishbones to go in, then fitted the bolts and torqued them to spec. I also used a permanent marker pen to mark the bolts that have been torqued. This way, during the build I will know which bolts and buts have been fastened properly.
After fitting the rear wishbones, I installed the dampers and the rear uprights. These were quite easy to fit and simply bolted on. The only things missing were the copper spacers for the top and bottom of the dampers. So far, there have been no missing parts in my order, so I decided to open more boxes. I eventually found that the team at Ultima stored the damper spanners and all of the copper spacers in the box with the front dampers, so nothing was missing.
The rear of the chassis started looking more like a car, so I could not help myself and had to install the rear brake disk kit.
The AP Racing kits are impressive, and even the way it is packaged says “I mean business”. These callipers were easy to fit, so while I was at it, I also fitted the handbrake calipers. None of these have been torqued up yet, as I mainly wanted to see what it looks like and take a picture of these impressive rotors and calipers.
This week, I spent another 30 hours working on the car, of which 10 hours can probably be attributed to carbon fibre work. This brings the total to 100 hours, with 24 of these hours spent on skinning work.
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21 May: More epoxy work done on the cockpit double skin panel, then leaving it to cure. I still had to complete the fitment of the brake calipers, but the rotors were not going all the way in over the studs with the tight clearances. I fitted the rear wheel in order to tighten the rotor to the wheel hub. This also gave me the opportunity to take some photos showcasing these massive rear tyres.
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22 May: After sanding and polishing the front bulkhead panel, I could finally rivet it down so I could continue fitting the front wishbones, wheel hubs and the steering rack.
The space inside the master cylinder area is too tight for the pneumatic rivet gun which means all these rivets had to be installed by hand riveter. Even though I read the manual several times explaining that the top rivets should not be installed at this time, I completely forgot about it and riveted all the top holes. When the body arrives, I will have to drill out all those rivets again. I will try and remember not to make the same mistake for the rear engine bulkhead panel.
The front wishbones and uprights were fairly easy to fit, only requiring some cleaning of the powder coating for the bolts to fit.
The steering rack itself is also easy to fit, but care needs to be taken to make sure the nuts and washers don’t drop into the chassis uprights. If you don’t use a longer socket, that can also fall in. I used a long size 13 socket and put some masking tape inside and on the front to secure the nuts and washers before putting them in.
To install the rubber bushes for the steering shaft is more of a challenge. It is important to heat them up with a heat gun or leave them in hot water so the rubber can soften, otherwise the rubber starts tearing while pushing the bushes in. I started with a smaller G-clamp, which broke while pushing the 1st bush in, so I had to use a larger, stronger clamp to push it in. I used some plastic squeegees between the clamps to protect the bush and frame.
