Fitting the Roll Hoops - 4 - Here we go!

Time to put the plan into practice. Having marked the underside of the boot off the studding and drilled a pilot hole upwards I then drilled two 25mm dia holes to expose the ends of the studding:You can see in the next photo the 6mm pilot hole in the studding to centre the hole saw mandrel. The piece of MDF you can see in the hole is the boot template being used to space the studding at the correct centres.These holes were not expected to be concentric with the studding due to the difficulty of marking the exact centre of the studding on the underside of the body from within the boot. The next step was to cut the two 51mm dia holes for the main legs:

These holes were gradually opened up with the Dremel until the bolts could be fitted and tightened without the legs binding on the edges of the holes. The hoop was fitted the wrong way round so that the back leg could be ignored for now:The MDF template was used to "spot" the pilot hole for the back leg. It was made from the leg spacing gauge as shown below:Because the hoop is being trial fitted the wrong way round you must remember to flip the template over when "spotting" the back leg hole on the body.

With the hole "spotted" a 38mm dia hole was cut in the body and the whole process of opening out started again until all three bolts could be fitted. The back leg needed to be pulled out a couple of mm and this was done by packing between the legs in the boot.

So the hoop is in but the holes are a but untidy. This was remedied by scribing round the legs using an M10 washer to give a 5mm clearance hole:

It is then a simple task to open out the holes to the scribed line. The best method is to use an 80 grit flap wheel in the Dremel -use 15,000 rpm for removing the bulk of the material and 10,000 rpm for finishing off. The end result is three nicely finished, perfectly circular accurately centred holes:

The roll hoop was loosely refitted and the grommets installed - purely as I wanted to see what it would look like. I found the 5mm clearance hole just about spot on for getting the grommets to fit snugly:

So it would appear that the plan has worked. Feeling flushed with confidence I decided not to fit the other hoop today - over confidence leads to mistakes. From start to finish it took me 6 hours to fit one hoop. But most of that time was spent double and triple checking and it can get a bit time consuming lifting the hoop in and out whilst opening out the holes a little at a time.

So to finish here's some gratuitous shots of the finished article. I don't think I'll bolt the hoops down permanently yet as they will only have to come out to fit the boot carpet.