Seat pan repair / Seat Concepts install

Discussion in 'GS Boxers' started by slartidbartfast, Feb 26, 2013.

  1. slartidbartfast

    slartidbartfast Love those blue pipes

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    Despite living with it for eight years, the stock seat on my 1100GS has never been very comfortable for more than two or three hours at a time. I aquired a Corbin which has a totally different feel but digs into my thighs at the front and is no better than the stocker after 200 miles - plus it weighs a ton and the pillion seat doesn't fit with it. Based upon the outstanding Seat Concepts seat I installed on my DR350, I have purchased a Seat Concepts kit for the 1100GS.

    Rather than tearing apart the perfectly good stock seat, I am trying to use a seat pan that came from a salvaged (underwater) bike. The seat pan was apparently damaged by a Bavarian upholstery gnome's over-zealous use of a trimming knife during assembly and at some subsequent point, the pan split.
    [​IMG]

    Here is the other side with the seat foam removed
    [​IMG]

    I have used a heat gun to soften the plastic and get it more-or-less back into shape but now need to repair the actual split.
    [​IMG]

    Plastic welding seems like the obvious way to go but I do not have any experience and am not sure what material the pan is made from. Do not really want to spend $50 on a hot air welding kit if there's an easier way - or if it is unlikely to work anyway.

    Can anyone offer any advice please?
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  2. JimVonBaden

    JimVonBaden "Cool" Aid!

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    Stainless steel safety wire sewing and a nice plastic epoxy over the wire. I did something similar to my ST headlight.

    [​IMG]

    For yours I would do closer stitching.

    Jim :brow
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  3. slartidbartfast

    slartidbartfast Love those blue pipes

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    Thanks JVB - I hadn't thought of that and I think I'll save it for a last resort. With the seat cover pulled tight, the edge of the pan will be pulled outward so the forces will be trying to bend the plastic along the repaired joint, not pull it apart as with your headlamp. Safety wire stitching seems like a good technique for repairing split fenders and plastic body panels in an emergency (along with liberal use of duct tape, of course!)
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  4. Lomax

    Lomax Nanu-Nanu Adventurer

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    Great job Jim. Your ingenuity really intrigues me some times. :clap

    Maybe I should have you hook up my Corbin seat. :lol3 I think someone got the wires on the switch wrong and the fuze goes pop when I turn it on. Or maybe I just need to spend some time with a meter this weekend. :lol3

    Marc
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  5. JimVonBaden

    JimVonBaden "Cool" Aid!

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    Definitely different stresses on a seat. IMHO, here are few plastic glues/fixes that can handle a lot of constant movement. I would consider a stitch of safety wire combined with your choice of adhesive.

    Either way, I am interested in seeing your solution.

    Jim :brow

    PS Lomax, take a ride in the spring and come on by! I'll buy the first beer!:freaky
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  6. slartidbartfast

    slartidbartfast Love those blue pipes

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    Been on the sherry this evening Jim? I'd like to buy a vowel please.
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  7. JimVonBaden

    JimVonBaden "Cool" Aid!

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    Argh, my damn keyboard is wireless, and the stupid antenna needs to be practically on top of the keyboard. May as well be wired. Combine that with the crappy typing skills that require me to look at the keys and this is the result! :baldy

    Jim :brow
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  8. slartidbartfast

    slartidbartfast Love those blue pipes

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    Does anybody know exactly what plastic the seat pan is made from, or how I would tell? These answers seem like a good starting point for figuring out the best substance to apply for repair.
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  9. Lomax

    Lomax Nanu-Nanu Adventurer

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    That's a hell of a ride for a Beer. :lol3 hopefully some day I will be able to do things like that.

    Marc
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  10. Gillus

    Gillus High Desert Rat

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    I had to repair a cracked plastic seat pan for a 12GS. I used harbor fright plastic welder, plugs into 110 for heat and uses regulated compressed air to blow it. Then a plastic lid off a gallon milk jug cut in pieces for welding rod and it worked well.
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  11. slartidbartfast

    slartidbartfast Love those blue pipes

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    Just the regular soft plastic from a screwcap? The seat pan on my DR350 looks like polyethylene but the 11xxGS seat is something else. It might be ABS but I'm not sure.
    #11
  12. MsLizVt

    MsLizVt pfft ...

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    Slartidbartfast, hi!

    If you have a moment to look at the back of your seat, you should find a bunch of numbers, some look like part numbers. But there should be one number that looks like this > PP + 20% TALK <. That means PolyPropylene, plus twenty percent talc added in for substance and strength.

    PolyProylene is a thermoplastic, which means it can be heated up again and it'll flow and bond. Harder plastics are most likely Thermosets, which means they can't just be heated up and flow, they have to be bonded. My guess is that Jim's headlight bucket is a thermoset, which means his mechanical and glue bond was probably the best option. It could have been welded, but it would have been a project.

    PP is common in household stuff, including bottles and containers. Most of the time you can tell on almost any bottle or container by looking for a symbol that might be a triangle with a number and then letters. For instance, look at your milk bottle, there should be a number 2, for number 2 plastic, the most common in household use, and HDPE, which is High Density PolyEthylene, different than PP. I'm not sure what the cap is, but there's a good chance it's PP. Soda bottles are different, they are number 1 plastic, PolyEthylene Terephthalate, PET.

    Actually, here you go. Bottle Caps

    As Gillus mentioned, you can just cut up pieces of bottle caps and melt them into the cracks. The key to welding plastic is the same as welding steel or aluminum, it's the preparation of the joint. Most of the time, you'd like to have a V groove that would be easy to fill, in this case, because the seat material is so thin, you might have to just wing it as best as possible.

    Gillus is right, a Harbor Frieght plastic welder would do the trick. They also come with a selection of plastic rods of all different types of material. Another option, and if this is your only plastic project, is to use a good soldering gun that has a flat tip, which often come with the soldering gun. You would heat and add plastic, heat, and add. It helps to have something on the back side of where your welding to keep the welding material from melting away.

    Another method that usually works pretty well is two part epoxies. Not all of them will work with PP, because PP generally is pretty flexible. Check the epoxy to make sure it'll work with PP. My best suggestion for using epoxy would be the rough up the surface, cut out a piece of wire mesh screen, spread out the epoxy, lay in the screen, coat with more epoxy. Do both sides for best strength. You can sand it down after, if you wish, but it's under the seat, my guess is you want function, not fashion.

    You could also find some sort of sheet of plastic, and to be honest, I would even use a milk jug, to put over the epoxy and wire screen/mesh, doing this on both sides, and then clamping it all. That might be overkill, but whatever works. For what it's worth, laundry detergent bottles are thicker.

    How's that for a start? Questions?

    Enjoy,




    Liz
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  13. JimVonBaden

    JimVonBaden "Cool" Aid!

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    Liz,

    Every time you post you impress me more and more! Great info!:deal:clap

    Jim :brow
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  14. MsLizVt

    MsLizVt pfft ...

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    Slart*, hi!

    Was just trying to think of anything that has PP in it that you could canibalize.

    Apparently white products, as they are called, like the plastics inside refrigerators and plastic on coffee makers, are PP, or some form of it. There will always (I think) be a recycle mark on the plastic, in this case a triangle with the number 5, and PP somewhere near by. Here's a link.

    http://www.thedailygreen.com/green-homes/latest/recycling-symbols-plastics-460321#slide-5

    Interesting that they have straws in there as PP. Those would make good little welding sticks. Ketchup bottles, syrup bottles, medicine bottles, and bottle caps.


    Liz

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  15. MsLizVt

    MsLizVt pfft ...

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  16. sdpc2

    sdpc2 Just another Rally Rat

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    I agree With Jim....

    Liz how do you know so much about this obscure sh!t.....

    I'm equally amazed
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  17. slartidbartfast

    slartidbartfast Love those blue pipes

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    Liz - This is brilliant! Thanks so much.

    I think I'm going to throw down for a hot air welder from HF. I can probably also use it to repair some of the brittle fairing panels on my GTS should such become necessary.

    Will post pics and let you know how I get on of course.

    Cheers!
    Slart
    #17
  18. MsLizVt

    MsLizVt pfft ...

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    Jim, hi!

    Thank you so much for the wonderful compliment. That means a lot!




    sdpc2, Hi!

    Oh gosh, let's see, it's partly in the genes, I think.

    Short story is my dad was in the car business, me being the oldest of all girls, it was me who he took into the shop to help out. Believe it or not, at 12 I was sanding cars in the body shop.

    My grandfather started the business, as one of the first Ford dealers in New England in 1922. When he passed away in the 1950's, my dad took it over. Unfortunately Ford closed the doors for him in the 1970's when the energy crisis hit and Ford closed 3200 other small dealerships. But I grew up around cars and bikes and snowmobiles.

    In my adult life, somewhere along the way in the 1980's, the opportunity creeped up for me to drive a Porsche on the track. Over time my driving skills sorted themselves out, with me being faster than most of the men on the track. That led to someone approaching me about driving a rally car, and one thing happened after another, with me ultimately racing pro rally cars for a dozen years, winning US National Championships, Canadian National Championships, North American Championships, Regional and Provincial Championships, and setting records at the Mount Washington Hill Climb. All those were regular championships, not gender specific.

    VW became my behind the scenes sponsor, and my biggest sponsor was myself. As you may or may not know, back then I had my own CPA office, with staff, and lots of clients. And you know, even racers need their taxes done. So at the time, I got tax work out of the racing too.

    But where I learned most everything was after the first couple of times at the track with the Porsche, when I came home and the car needed a bit of work, like tires swapped, or tune up, or whatever. Sending it out to the mechanics after every race became costly.

    My first move was to trade a bunch of a clients tax work for a Snap-On top box, then reading, reading everything I could get my hands on, and this was before the internet. Once I started racing rally cars, next was an F250 tow vehicle, two car trailer, tire changer, compressor, bead blaster, parts washer, etc, etc. There were a couple of guys who loved going to the rallies with me, and loved working on the cars. We did it together.

    I learned pretty early on that I would never be able to get pregnant due to some medical issues when I was young, and that was okay. So instead of having a family, I had a business and a team.

    If you look at my little photo in my profile, not the one of me in my leather dress, but the one in front of the car, you'll see one of my rally cars, and one of the bicycles. That was taken when the Boston Globe had come up here to do a feature article about me being the only person to race up Mount Washington by foot, by bicycle, and by car, in the same year. I was in better shape back then.

    My rally world ended in the early 2000's and motorcycles came back into my life more.

    Here's a bit more history, from when someone was picking on me about my rally lights on my GS.

    http://www.advrider.com/forums/showpost.php?p=11021581&postcount=148

    So to finish with how I learned all this stuff, it's mostly been out of necessity, and enjoying being hands on.

    I married late in life, and subsequently went through a horrific 9 year long divorce, in which my lifestyle was turned upside down, and I had to give up my business, most of the properties, and had to file bankruptcy to pay off my ex's debt. So now, my world is more austere, and instead of buying new parts, I fix what I have.

    One of the skills I learned from my dad was " ... don't be afraid ... figure it out and make it work ... " and the skills I learned from rally racing give me the confidence to do things like redo Hall Effect Sensors, and weld plastic.

    One other thing from rallying that I learned is to not be afraid. When you're sliding sideways at 100mph on ice and snow, with trees four feet on either side of you, fear isn't what you need, it's finesse and confidence.

    Sorry for the thread hijack, Slart. Mostly, I don't speak up about how to fix bikes, because most times there are a lot of people on here who do know, and they would say things that I would probably say anyway. But with your fixing the plastic, it seemed like it was time to help out. ADV is truly a man's world, and I'm sort of out of place, so I pick my posts carefully.

    Does that help explain?

    Enjoy,



    Liz
    #18
  19. MsLizVt

    MsLizVt pfft ...

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    Slart, hi!

    You're so welcome!

    Getting the welder from HF totally makes sense. As is common, you'll probably find a lot of things that you can fix with it, that you never thought of.

    For what it's worth, you might want to get a book on fixing plastic. I confess, that's where I learned. Let me see if I can find the book I have.

    http://www.amazon.com/How-Repair-Plastic-Bodywork-Money-Saving/dp/1884313809

    http://www.whitehorsegear.com/books/maintenance/how-to-repair-plastic-bodywork-2nd-edition

    Please do let us know how it goes.

    Enjoy,



    Liz
    #19
  20. slartidbartfast

    slartidbartfast Love those blue pipes

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    MsLiz was absolutely right (of course). The seat base is indeed marked to indicate polypropylene with 20% talc
    [​IMG]

    I picked up a HF plastic welder and a burr for my Dremel
    [​IMG]

    Had a bit of practice on an old steering column shroud - with mixed results. I think the welding was ok but the shroud was so brittle it was cracking in new places faster than I could weld it up.
    [​IMG]
    #20