Best way to bend this seat pan

Titan performance

Titan cafe racer builders.
If your pan is largely going to sit on the frame tubes, aluminium will work just fine. It's easy to work and shape, and attaching some heavy rubber strips will help cushion it.
 

doc_rot

Oh the usual... I bowl, I drive around...
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Putting fresh upholstery in the sun is a common tactic by shops to make the material shrink fit tight. Every seat will do this but it depends on how tight you stretch the cover to start with and also how the seat pan is attached to the frame. Most seat pans only have a couple mounting points which let it taco. However if you attach the pan in a way that causes it to be pulled to the underlying structure, like fasterners around the perimeter you casn negate the effect of the cover shrinking with a dead flat pan.

I have made a couple fiberglass seat pans and the problem with those is that unless the resin is heat cured before stretching a cover the seat pan can move when it gets hot the first time as well. You end up having a multiplying effect where the seat cover gets hot and shrinks, it pulls the fiberglass seat pan which is soft from the heat and the whole thing goes taco. Then it cools this way, and its tough to undo. It doesn't move a huge amount. This happened to me with the first custom seat on my KZ1000, I ended up with about a 1/2" gap between the seat and the tail. This is not a huge gap by factory standards, but, dammit this shits custom, it needs a better fit. The last fiberglass seat pan I made I basically took a mold off a factory seat pan, so all the features of a factory seat pan were present in the fiberglass version, and this seat pan did not taco.
 
Well, it looks like this pan is going to be quite a bit more complex than I thought given the tank choice. The tank is off a 750c and doesnt have that nice lip like the f or k tank does. So I'm going with this front piece to take up the gap .... should provide more rigidity, too.

I should have used a bit bigger diameter pipe for my home-brew sheet metal brake die, but oh well .... we'll see

Trying to avoid the gap like this guy here has .... while I love his seat that gap really takes a lot away from it.

I'm guessing the seat he bought was for a k or f model where the front of the seat tucks nicely under the lip of the tank, but just doesnt work well with a 750c model tank

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I ended up reworking the front piece with more rounded corners to hug the tank better. He plan is to weld this to the seat pan and use several mounting points to eliminate the taco problem.

This being 18 gauge steel, I might just secure with bolts and jb weld to smooth out instead of welding.

I think it will work well.

Questions:
1. What glue should I get?
2. Has anyone tried to reuse the stock seat foam material??

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pidjones

Well-Known Member
Seat foam - go to a carpet store and get (free left-over if available) "rebond" carpet padding. Glue with 3M 80 (home improvement store) and trim with electric carving knife (NOT the wife's - you can find them cheap on ebay). Build layers until you get the shape you want.
 
Seat foam - go to a carpet store and get (free left-over if available) "rebond" carpet padding. Glue with 3M 80 (home improvement store) and trim with electric carving knife (NOT the wife's - you can find them cheap on ebay). Build layers until you get the shape you want.

Isn't that stuff a little too firm? I was really hoping to rework the stock seat foam to the right shape ...... if possible, because it seems more comfy :)

I've used 3M super 77 and it's a great adhesive. What's different about 80? Is it better? or just better for foam type materials?

Thanks!
 

pidjones

Well-Known Member
80 is permanent and strong. They put headliners in with it. Carpet padding is firm, so your butt doesn't sink down to the frame. Maybe if you weigh like 140 pounds you could go softer. I went to a foam store - they sell all sorts. The guy told be get carpet rebond padding. After initial shape with the electric knife, you can fine tune with course grit on a side grinder. If you can find some thin, firm neoprene you could put a final smooth layer of that down but if you think ahead your final padding foam layer will do.
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Damn. Got the pan finished up tonight ... but the stock seat foam ain't gonna work with the flat pan. It raises up in the rear too much and it's no good.

The pan turned out awesome, I think.
Got 8 bolts holding the two together. Not sure if I should smear on some JBWELD as well for good measure.

Not to toot my own horn, but almost a shame to cover it all up

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Maritime

Well-Known Member
that turned out well. Are you in Canada or USA? I have used a closed cell kneeling pad you can get from Princess Auto in Canada. It isn't the dense stuff like the puzzle piece mats you can get its firm but also squishy. Hard to describe but like thick neoprene. I made a cafe seat and covered a piece of that with vinyl then attached it to the seat. It was 8 hr comfortable. I road from Moncton, NB to Brifdgewater NS all back roads, 1 stop for lunch and 8hrs total and my but was fine.

This is the one. When you squeeze it you'll see why it's so comfortable. 2 layers of that with a cover would be all day long comfort and still thin and sleek.

https://www.princessauto.com/en/detail/15-x-20-in-kneeling-pad/A-p8099442e
 

DesmoDog

Member
I used what looks like the same type of foam pidjones did. The upholstery guy I used recommened it and it turned out to be more comfy than I was expecting.

I used a carving knife and a belt sander to shape mine. Ended up doing it in seperate pieces and gluing them together, worked out fine. The mistake I made was putting a curve on the base where it met the bum stop, it made it harder to attach the cover when it was done. I'm pretty sure he put a thin layer of foam over all of it before covering it to smooth everything out a little.













I added the badge and trim strips after the recovering was done.
 

Jimbonaut

Well-Known Member
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Nicely done indeed. I'll be starting work on a seat pan soon and have a few ideas rattling around in my head. Your approach has given me a few ideas!
 
that turned out well. Are you in Canada or USA? I have used a closed cell kneeling pad you can get from Princess Auto in Canada. It isn't the dense stuff like the puzzle piece mats you can get its firm but also squishy. Hard to describe but like thick neoprene. I made a cafe seat and covered a piece of that with vinyl then attached it to the seat. It was 8 hr comfortable. I road from Moncton, NB to Brifdgewater NS all back roads, 1 stop for lunch and 8hrs total and my but was fine.

This is the one. When you squeeze it you'll see why it's so comfortable. 2 layers of that with a cover would be all day long comfort and still thin and sleek.

https://www.princessauto.com/en/detail/15-x-20-in-kneeling-pad/A-p8099442e

BC, canada! :)

Thanks for the link. I'll have a look next time I'm at PA.

The seat pan sits directly on the frame rails. Should I use some rubber strips in between? The stock pan sits on about 5-6 rubber cushions, but is stamped and more rigid. Thinking a strip of rubber around the perimeter of the pan

(Which I guess I would have to add after the upholstery?) Thoughts?
 

Maritime

Well-Known Member
You're gonna need to rivet the cover to the pan and then a strip of firm rubber would be a good idea to protect the frame paint from the rivets and also help from vibration transfer.
 
You're gonna need to rivet the cover to the pan and then a strip of firm rubber would be a good idea to protect the frame paint from the rivets and also help from vibration transfer.
Arent a lot of folks just gluing the covers on?
I do agree, rivets would probably be easier for me to get a nice tight fit on there.

That's another thing I need from Princess Auto ... a rivet gun. Are there stainless rivets?
 

Maritime

Well-Known Member
I think there is but you can get steel for sure. one thing to think about is if you want the cover tight, you will need some strength to the pan front to back. the way it is now when you pull the cover on you'll curve your pan and it won't be flat anymore. a couple pieces of small square tube or angle along the sides or up the middle on top or under would work to prevent the clamshell closing. Hard to explain I was going to draw it but couldn't really. You need to make the thing not able to bend easy front to back to get the seat cover right.

These might help:



 
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