ORGS build up

[Benjamin M]

..anything much happened in the last four months?

[Chadleys1]

Originally Posted by Benjamin M

..anything much happened in the last four months?

Ditto.
This has really been a great thread.
Thanks.

[Benjamin M]

What happened? Finish the bike!

[_anatic]

[Benjamin M]

Originally Posted by x3300

Hi All,

I got sidetracked on a few other summer projects and a lot of riding, and so haven't been doing much other than research and collecting ideas for my ORGS. I plan to switch back once the rain comes toward the end of the year.

One of the projects was to get a truck and get it into shape so I'll have something to haul the bike around with as needed before it becomes fully road worthy.

-x3300

Okay, we'll let you off then... Just checking

[Box'a'bits]

So dredging this thread back from the dead, any progress? . A man can only stomach so much popcorn....

[beeks76]

My God! I just read through this entire thread with my anticipation building like a teenager on his prom night, waiting for the climax and BAM, no finished photo. I think I am going to have blue balls! At least give us an updated photo.

[x3300]

The old seat pan I had made no longer works with the new subframe, plus I was not entirely satisfied with the way the old one turned out, so I decided to make up a new one. I started with a model made from thin cardboard that I thought looked good on the bike, and then transfered that pattern to some 3/32" aluminum sheet I had been saving.



I used a squaring shear to trim out the blank.



And used this sheet metal brake to bend the sides to the angle I had decided on with the cardboard model. To get the large radius bend from the brake I set the brake fingers back about 20 mm from the hinge joint, the setup of which can just be seen in this view.



Here's the formed pan compared to my cardboard model. I rounded down the sharp corners with a file.



To space the pan from the frame and to add some stiffness I cut these sections from aluminum rectangle stock. As can be seen, in preparation for welding I cleaned up the area around the stiffeners with a flapper disk on an electric angle grinder.



I had planned to make a slip-in front mount to make it easy to access under the seat, but decided for now to simplify the mount and just have it bolt together. I'll add the slip-in mount when I make an under seat storage box. For the frame side of the mount I attached this section of aluminum angle stock to the rear seat mount and drilled a single hole in its top.



I found I needed to do some rework on the pan's front mount once I got it fitted on the bike. It was too wide to fit within the subframe mounting bolts. With the pan centered on the bike I drilled up through the hole in the frame mount and into the pan mount and pan.



To hold the blind side of the front mount bolt which will be covered by the seat foam and cover I welded a tab to the head of a bolt and fixed the tab to the pan with a pop rivet. I ground the bolt head down to a lower profile.



For the rear mount I made these tabs to weld to the subframe.





On the seat pan I welded two tabs cut from 1" x 1/8" aluminum stock.



I used these clip-on nuts for the rear mount bolts. I may weld some nuts on the bottom of the frame tabs the next time I have the subframe off, or better, make a locking quick release mechanism to work with the slip-in front mount.



Here's the seat pan ready for foam and a cover. The side panels really aren't necessary, but I didn't want to just have square block of a seat there so I put on some sides with angles that looked interesting when viewed together with the tank and subframe.



-x3300

[Toyanvil]

[Zebedee]

Originally Posted by toyanvil

+1

[x3300]

I had been looking around and collecting different kinds of foam samples to mock up and test the seat with. After some trials I found that a base layer of rebond foam with another layer of firm weight upholstery grade open cell foam over it provides enough bottoming protection from the rebond and enough cushion from the open cell. Here's a view of the bare seat pan.



These are the things I used on the foam. An angle grinder with an 80 grit flapper disk, some coarse sand paper and a block of wood, a hack saw with a 32T blade for cutting the foam into shapes, some 3M Super 77 adhesive spray, and some Three Bond 1521 adhesive. I didn't really use the Three Bond 1521 though.



I just had some strips of rebond foam, so I cut three pieces with the hacksaw and glued them onto the pan with some Super 77 adhesive. I put a slightly thicker piece at the back with the idea of making a kind of stepped profile. I used the angle grinder to flatten the surface and shape the step at the rear. The angle grinder and flapper disk worked really well at shaping the foam, but it was touchy to control. If the disk was not close to flat it would grab into the foam and remove too much.



After I got the base layer shaped I added a layer of firm weight open cell made from three strips.



Then used the angle grinder to flatten the top and shape the sides to match the contour of the pan sides.



To finish and level the foam I used the sand paper and block of wood. The block sanding worked well to level the surface, but tended to round the corners of the foam as the foam deflected under the sand paper. This rounding didn't happen with the angle grinder. I could get a really sharp corner with it, but found I couldn't control it well enough to smooth a large surface.



This view shows the layers and how I shaped the sides to match the seat pan.



I had read a write-up on seat making that recommended having a final layer of soft foam on the seat, so I added a layer of this pink soft weight open cell foam.



Here's how it looked on the bike. As can be seen the soft outer foam makes all the corners rounded, and when I tried wrapping some fabric around it to mock a seat cover I found it to look like cheap over-stuffed furniture.



I tried pealing, shaving, cutting, scraping, but the only way I could remove the outer foam was with a wire wheel mounted in a hand drill. The result on the floor was not pretty. Heres the stripped seat. I made a few gouges at first until I learned to control the wire wheel.



I went over it with the flapper disk and sanding block to get the remaining glue off. There is one remaning gouge I need to fill before its ready to cover.



-x3300

[x3300]

I wanted to put a leather cover on the seat, but wanted to get something that had a good looking grain and some grip in its texture. I stopped by the LeatherWise leather shop in Santa Cruz, CA and talked with owner Ross Levoy. He told me all about leathers, and after looking over his stock I ended up leaving with a four square foot chunk from a black 2 oz. chrome-tanned cowhide skin.



I did a trial fitting of the material and marked off the seam corners.



Then used some taylor's chalk and a rule to layout the seams. This shows the rear panel and its layout.



Since this leather was soft and fairly thin I just used a conventional electric sewing machine to stich the panels together using plain seams.



I used some leather specific thread and a conventional #16 needle. I have seen leather specific needles though, and have heard standard nylon thread
will work OK. I'll try some leather needles next time, as I did have a little trouble with the thread binding.



Leather is kind of thick and stiff, so to finish the seam I used some Three Bond 1521 adhesive on the seam allowance and adjoining fabric.



Once the glue setup I pounded the seam flat with a rubber mallet which put a nice crease in the leather.



I decided to put a stitch along the allowance to complete the finish, but I think the glue would have been enough to keep the seam flat.



Once I had the cover sewn I used some spray adhesive to glue it down to the foam and seat pan. I ran out of 3M Super 77 Adhesive spray so used some 3M General Trim Adhesive spray. I couldn't really tell any difference between the two.

On the bottom I used plenty of spray and stretched and folded the leather over the corners to get a smooth wrinkle free top. I trimmed down the excess and pounded the folds flat with the rubber mallet. I had planned on using some strips of stiff plastic and pop rivets to hold the underside of the cover from pealing away from the pan, but the 3M adhesive alone seems strong enough for now. I'll add something more if it starts to peal.



Here's how it looks on the bike. I now have a custom leather seat to fill the gap behind the tank. It seems a little short when sitting on it, and I think I'd like to have a little padding on the sides too, but I'll need to do some riding with it to make a real judgment.



I've done a lot of sewing in the past but mostly with nylon and fleece. This was the first major work with leather. I always find sewing very satisfying and recommend it to everyone. Its like welding without the heat, gloves and helmet.

-x3300

[Padmei]

Great write up. Thanks for taking the timeto do this. I agree about the sewing/ metalwork comparison- different skills but same thought processes.

[Zebedee]

Originally Posted by Padmei

Great write up ...

+1

... and it's great to see the build back on track

[mikyheimann]

But you must have an iron butt!!