Pasted from my bigger thread to update this one:
Also kicked off my seat build today. Always preferred steel to fibreglass but didn't know how I was going to do the bump stop.
Decided to just start and see where it took me. Used the upside down frame to trace the seat pan out. Cut it out with the angle grinder:
Plan is to weld these bits together at the end with some bracing behind. Next up I needed to bend the sides down, a tough job as I could only do it by hand and in the end I used the angle grinder to help start the process. Here it is post bending with extra long sides so I can trim them back:
On the bike:
Next up was cutting the seat pan back further to bend up the rear of the seat area, the plan was to curve it up like Benjie's seats so I used my rear hub to get the curve:
Next up was cutting the bent up rear seat section, I used my grinders disc as it was almost the perfect size:
A nice line from the tank through to the bump stop:
Afterwards I cut the first of the segments, made an error here as I really should have made both sides out of 1 piece to minimize the welds, might redo it tomorrow. It needs trimming too as its a bit too wide still:
This first section will probably get cut by about half so I have enough room on the end to get a nice rounded end piece. Then need to French in a rear light.
Bit more seat work done today. First question was how much of the frame rails do I want to expose. I cut the edge to 1" first as I could always cut again, I do like this look though so it will probably stay at 1":
Just the slightest amount of frame visible and it gives a nice sharp edge to the seat area. Test fit with knee scoops to check the lower lines:
Everything so far:
I suspect the rear bump is a little on the tall side. It's quite large and seems a little goofy. I was playing with the idea of trimming approx 15mm off the height as most nice looking bumps seem to be slightly shorter than the top of the tank (Bonita Applebum and GoingsMoto's to be precise). Anyone got some inputs? Estimated new line:
New shape:
Old lines:
All the electricals and battery will be going in the bump but I plan on getting an antigravity battery so I don't need a huge space.
So the plan for this weekend was to redo the bump stop section to get rid of the extra long flat bit and also tidy up the tank holes in preparation for welding in the panels. I have signed up to the Sydney Cafe Racers Facebook page and found someone with a TIG welder that is going to help me get the seat and tank finished.
Had 2 goes at the bump stop today... the first ended up in the rubbish bin, the angles weren't working as I was keeping one side straight and curving the other for each leaf as per the original version. It turned into a shit fight so I came up with a more mathematics based solution:
1. Cut out sheet metal and mark up 10 leaves (2 of these will be cut off at the end leaving me with a fully curved rear section):
2. Cut a curve on each leaf side. Didn't have a compass so ended up using a length of masknig tape stuck to my pen, it worked out ok):
You can see the difference in the leaves between the old version and new version:
3. Carefully bend them and mount it on the bike to get a look:
I think it looks 10x better than the old one
I also mounted the engine (now with studs removed
) and thought I would test fit the motor and carbs to get some thoughts around how I am going to get fuel out of the tank (as I have cut the original tap mount when I cut the knee scoops):
