Help!!!

Sorting out your thrunge brackets, fettling your inter-rositers and even stuff about bike parts.
Westonpark
Posts: 41
Joined: Sun Jan 03, 2016 08:40 am

Help!!!

Postby Westonpark » Wed May 15, 2019 11:53 am

Hi all,

I'm in need of some help.

I've just had a strip down service to find that someone has filled the down tube with expanding foam, to stop any rattling (I guess)

However its improssbile to change the cables out since they are all stuck in the foam!

Any idea on how to dissolve or remove the foam?

Thanks

oxoman
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Re: Help!!!

Postby oxoman » Wed May 15, 2019 12:18 pm

Ouch. Can't think of anything that will dissolve it easily. Only thing I can think of is stiff plastic pipe or rod and force your way through the foam. I'm assuming you can't re-use the liners already embedded in the foam. Sadly PU expanding foam isn't very easy to recycle / remove. Tends to get reused as filler for pĺastic park benches or traffic come bases.
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Long Time Lurker
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Re: Help!!!

Postby Long Time Lurker » Wed May 15, 2019 12:55 pm

When you say filled, is it the whole tube or just a small section?
I used to use foam cleaner when installing UPVC windows - but it was never inside anything.
You can buy Everbuild Foam Eater, but that is a paste so may not work inside a tube.
Other option is something like Tytan Foam remover which is a spray.
But both need you to be able to access the foam/tube and do some scraping.
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Alejandrosdog
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Re: Help!!!

Postby Alejandrosdog » Wed May 15, 2019 15:41 pm

ok here is a solution

your cables are either in an outer or not
attach your internal cable routing tool (the park tool one or similar) to the existing cable
remove the existing cable and pull through the cable routing tool
discard the original cable but leave the cable routing tool hanging out both ends
attach new cable and pull through.

use the existing cable outers if your bike has them.

there must be a route through the foam because the cables need to move.

If youve pulled the cables out without attaching them to a internal cable routing tool then prepare for some fiddling and tears. irrespective, if theres a channel sufficient for the cable to move and actuate the gears then theres a channel you can feed the cable through. Again the tool might help and failing that a very strong magnet and some patience.

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eric draven
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Re: Help!!!

Postby eric draven » Wed May 15, 2019 15:45 pm

Long Time Lurker wrote:When you say filled, is it the whole tube or just a small section?
I used to use foam cleaner when installing UPVC windows - but it was never inside anything.
You can buy Everbuild Foam Eater, but that is a paste so may not work inside a tube.
Other option is something like Tytan Foam remover which is a spray.
But both need you to be able to access the foam/tube and do some scraping.

The Everbuild Foam Eater could that be watered down a bit,if it could maybe try getting some in the downtube via the head tube or the bb shell
Westonpark I don't envy you on this job

Tom Howard
Posts: 1865
Joined: Thu Nov 07, 2002 16:24 pm

Re: Help!!!

Postby Tom Howard » Wed May 15, 2019 15:53 pm

Westonpark wrote:Hi all,

I'm in need of some help.

I've just had a strip down service to find that someone has filled the down tube with expanding foam, to stop any rattling (I guess)

However its improssbile to change the cables out since they are all stuck in the foam!

Any idea on how to dissolve or remove the foam?

Thanks


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larkim
Posts: 2255
Joined: Mon Oct 24, 2011 08:19 am

Re: Help!!!

Postby larkim » Wed May 15, 2019 18:01 pm

Alejandrosdog wrote:ok here is a solution

your cables are either in an outer or not
attach your internal cable routing tool (the park tool one or similar) to the existing cable
remove the existing cable and pull through the cable routing tool
discard the original cable but leave the cable routing tool hanging out both ends
attach new cable and pull through.

I suspect the problem here would be that the exp foam will not allow the cable outers etc to be pulled through at all - it's sticky stuff and may not move even with some serious brute force. If it was as simple as passing a new outer or inner through a hole in some exp foam I don't think there would be a plea for help!!
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Westonpark
Posts: 41
Joined: Sun Jan 03, 2016 08:40 am

Re: Help!!!

Postby Westonpark » Thu May 16, 2019 05:51 am

Thanks guys.

The whole frame isn't filled. It's as if somebody has just sprays some thorough the head tube. However it's basically welded the cables together!

Ive managed to free three out of four cables, however the one that is still stuck is the rear brake cable and that needs sorting since the brake doesn't work. Fingers crossed its just a new lever or piston rather than the cable, otherwise its foam eater or external routing.

I cant afford an new frame! :(

Westonpark
Posts: 41
Joined: Sun Jan 03, 2016 08:40 am

Re: Help!!!

Postby Westonpark » Thu May 16, 2019 05:53 am

Will the foam eater damage the carbon frame??


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