Seat base pan material question


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crazzy450z
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Seat base pan material question

Post by crazzy450z »



Does anyone know what material the seat base is made of? I am working on building a custom seat for my 83'. I am looking to lengthen it in the drivers area. I plan on using two seat bases, and cutting them to add +-2" to the length in this area.. I also want to reshape the passenger area. While doing this, I'll need to re bond the parts together. I was wondering if anyone had done any bonding of the seat pan? What they used and how strong was it? Thanks in advance..


joecoolsuncle
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Re: Seat base pan material question

Post by joecoolsuncle »

my 84 1200 seat base appears to be abs plastic. i will be following the thread and am very interested in doing the same.
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crazzy450z
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Re: Seat base pan material question

Post by crazzy450z »

I posted this same question on a Facebook group I'm a member of. A fellow member there thought it may be polyethylene. I am not a plastics expert, so I don't know how to differentiate between plastics. I figured someone from this group must have done something with the seat pan at some point. Either modified or repaired one..
joecoolsuncle wrote: Mon Feb 28, 2022 5:44 am my 84 1200 seat base appears to be abs plastic. i will be following the thread and am very interested in doing the same.
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Re: Seat base pan material question

Post by WingAdmin »

I didn't answer this post straight away as I don't recall what the seat pan was made of. But I do recall that it felt different than ABS, more slippery, like nylon or polyethylene - but soft enough to put staples into. It was also uncolored. Unfortunately, unlike most bodywork pieces, it doesn't have molded in-markings specifying the material type. Maybe it does on the top, the part that is covered by the seat cushion?

GL1100 Seat Pan
GL1100 Seat Pan


GL1100 Seat Pan
GL1100 Seat Pan

If you can cut/sacrifice a small piece, perhaps you could perform some of these tests: https://www.injectionmould.org/2019/04/ ... ification/
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crazzy450z
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Re: Seat base pan material question

Post by crazzy450z »

I have a seat with the vinyl stripped off and the foam loose, I'll check for markings. My main issue is going to be how to bond the parts. Polyethylene is notably difficult to bond. Epoxy resin apparently does not stick to it. I am planning on having the sections overlap by at least 1". I have found an adhesive that may work. https://www.gluegun.com/products/mma-50 ... 5761796249. I also plan to physically connect the parts with either screws or rivets..
WingAdmin wrote: Mon Feb 28, 2022 9:43 am I didn't answer this post straight away as I don't recall what the seat pan was made of. But I do recall that it felt different than ABS, more slippery, like nylon or polyethylene - but soft enough to put staples into. It was also uncolored. Unfortunately, unlike most bodywork pieces, it doesn't have molded in-markings specifying the material type. Maybe it does on the top, the part that is covered by the seat cushion?
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WingAdmin
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Re: Seat base pan material question

Post by WingAdmin »

crazzy450z wrote: Mon Feb 28, 2022 6:04 pm I have a seat with the vinyl stripped off and the foam loose, I'll check for markings. My main issue is going to be how to bond the parts. Polyethylene is notably difficult to bond. Epoxy resin apparently does not stick to it. I am planning on having the sections overlap by at least 1". I have found an adhesive that may work. https://www.gluegun.com/products/mma-50 ... 5761796249. I also plan to physically connect the parts with either screws or rivets..
WingAdmin wrote: Mon Feb 28, 2022 9:43 am I didn't answer this post straight away as I don't recall what the seat pan was made of. But I do recall that it felt different than ABS, more slippery, like nylon or polyethylene - but soft enough to put staples into. It was also uncolored. Unfortunately, unlike most bodywork pieces, it doesn't have molded in-markings specifying the material type. Maybe it does on the top, the part that is covered by the seat cushion?
Put some MEK or ABS cement on an inconspicuous spot. If the surface of the plastic gets soft and "tacky" then you can be reasonably sure that it is ABS, and can be bonded using ABS cement.
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Rambozo
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Re: Seat base pan material question

Post by Rambozo »

While a different model, my seat base sure feels like a polypropylene or high density polyethylene. I've never had any chemical bond that works on those. However, I have had a lot of it friction welded with great sucess. Mostly welding fittings into spray tanks, but once I had a strip cut out of a tank and welded it back together to make it smaller. I think that was done with hot air welding. Not pretty but held up leak free for many years.
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crazzy450z
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Re: Seat base pan material question

Post by crazzy450z »

It's definitely not ABS.. I took a little off cut and soaked it in MEK for 30 minuets and it didn't even soften.

After doing some reading, a couple sites mentioned passing a flame over the surface to do a "pre treatment" to the surface. I guess it changes the chemical makeup of the surface of some plastics making them easer to bond.. I did this and tried a ABS slurry as well as 3m DP110 - 10 minuet 2 part epoxy. Neither one structurally connected the test parts. They came apart with mild hand strength.

The next product I'm going to try is 3m's DP8010, its a structural plastic adhesive. I may have to pre treat the surfaces with this as well.
WingAdmin wrote: Mon Feb 28, 2022 8:32 pm Put some MEK or ABS cement on an inconspicuous spot. If the surface of the plastic gets soft and "tacky" then you can be reasonably sure that it is ABS, and can be bonded using ABS cement.


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