Author Topic: Best way to mount studs into fiberglass seat pan? Quick fab question.  (Read 5610 times)

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Offline aperry

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Hi guys, quick question:  I'm getting close to the end of my basket case cafe project.  I have a Roc City fiberglass cafe style seat/cowl piece that I've mounted to the frame.  Now I need to start thinking about the seat pad.  For this I'd like to make a fiberglass pan formed to the shape of the curve of the existing Roc City seat, and then build the pad with foam and wrap it with leather (or maybe nylon).  I'd like to mount the new pan to the existing fiberglass seat/cowl using studs.  What is the best way to attach the studs to the new fiberglass pan such that the bottom of the pan stays flush (only studs protruding, no nuts/washers)? 

I'm thinking about following something like this to build the pad:
http://www.chopcult.com/forum/showthread.php?t=1590

Of course the top of the studs would be inaccessible once it's all closed up.

Sorry if my terminology isn't quite right.  Many people would probably consider the existing Roc City piece the "pan".  Not sure how to make the distinction between that and the support that I intend to make for the pad.

Thanks!
Aaron
CB750K3 with F1 frame/swingarm

Offline Scott S

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 Why not use heavy duty velcro? That's the way some of Omars seat pads mount and, trust me, they will NOT fly off.
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Offline aperry

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Thanks.  I've noticed that in some of the threads around here.  I didn't know how legitimate that is, but maybe it's the best ay to go.  Thanks for the tip.
CB750K3 with F1 frame/swingarm

Offline shinyribs

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Rivet-nuts and furniture nuts work well for this.

Rivet-nuts are exactly like they sound. It is a rivet that you tighten with a special tool and when done it leaves a threaded tube sitting almost completely flush with the surface. Harbor Freight sells a kit that works good.

Furniture nuts are basically flanges that have 2,3 or 4 holes around the perimeter depending on which model you pick up. It is basically the same as a rivet nut,except instead of the actual fasten riveting itself into place you use rivets in the perimeter holes. These are what I used when I mounted my seat. These too dont sit 100% flush,but i always just use a thin rubber washer under them anyways. Lowe's sells these in various sizes.

I rivet nut grasps a pretty small area. Since you are using 'glass I would probably go with a furniture nut. I have the same job to do and that's what I will use. You can turn the furniture nut ( some call it a T-nut) to where the stud is up inside the seat if you have clearance for that,but I like to mount them with the stud sticking down. That way you can let it protrude thru whatever mounting tab you have and it will help locate the seat. I then use rubber washers on both sides,and a regular metal washer before the fastener goes in to the furniture nut. It helps to prevent the surfaces from scratching the finish on your frame where the tabs are,and possibly eliminate a little vibration.

Hope this helps!     

Rivet nut:
http://www.rivetsinstock.com/tool-kits.html

Furniture nut:
http://www.hystron.com/index.php/english/products/detail/15
« Last Edit: July 05, 2012, 11:46:52 am by shinyribs »
The darn fool didn't know it couldn't be done...so he went ahead and did it anyway.

My Hackjob build- http://forums.sohc4.net/index.php?topic=106103.0

Offline lucky

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Use elevator bolts. you can get them at the hardware store.
Just fiberglass them on. LUCKY
« Last Edit: July 05, 2012, 11:59:16 am by lucky »

Offline aperry

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Thanks guys, these are all great ideas!  I appreciate the info.  This seat pad project was something I was dreading, but the more info I discover from people who have done it, the more excited I am to give it a try.

Thanks again!
CB750K3 with F1 frame/swingarm

Offline jamesb

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i made some brackets out of aluminum  and bolted them to the  frame drilled small holes on top then tapped them and ran screws through the seat pan.
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Offline aperry

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Wow, that's pretty sweet jamesb!  Looks real clean.  Thanks!
CB750K3 with F1 frame/swingarm

Offline Lostboy Steve

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I used these little nut things. Basically looks like a lock-washer with teeth and a nut all in one. Then it got fiber-glassed into the seat pan. But that was so I could screw into the seat pan. So for your needs. I would weld a giant washer to a small bolt and fiber-glass that in somewhere.
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Offline aperry

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Another awesome idea.  Man, you guys are great.  Thanks.  I'm sure this is all plenty obvious to you guys.  But being my first build, I haven't had a chance to use many of these tricks yet.

Thanks again!
CB750K3 with F1 frame/swingarm