DIY Large Rubber Washers?

[youngsyr]

I've just picked up a cold air duct kit that shields a cone filter from the engine bay, the only problem is that the hole for the filter/induction pipe is significantly larger than the pipe/filter that I want to run.

The hole in the duct for the pipe/filter is 90mm ID and the filter/pipe I want to run is 70mm ID, so I thought that I could create two rubber washers 110mm rubber washers, seal them with instant gasket or similar on either side of the duct and then push the piping for my cone filter through them to create a seal.

Can anyone suggest where I might be able to buy two ready made washers in this type of size, or a type of material and source that I could buy in sheets and cut to shape?

Thanks in advance. Pic below:

[HellDiver]

Cheap rubber mats from your nearest Poundland type shop should do it.

[youngsyr]

HellDiver said:

Cheap rubber mats from your nearest Poundland type shop should do it.

Thanks for the tip, but won't they be a bit thick?

I was hoping to be able to get away with rubber that is around 2mm thick and I'm quite happy to pay a little extra if need be to get a neater result.

[mercfunder]

Contact any of the companies that fabricate hoses, they should have rubber sheet calendered to the right thicknkess and will be able to cure them off in an autoclave.

Try these guys: http://www.indicorubber.co.uk/

[BliarOut]

Use some self adhesive rubber strip? Affix most of it and leave the backing on near the join. Run a sharp knife across both layers and then fix. Job's a good 'un.

[-Pete-]

70mm holesaw from screwfix or eBay, two CD's and some glue?

[youngsyr]

Thanks for the tips all - I was kind of hoping to just be able to pick up an A4 sized sheet of 2mm thick rubber and then just cut the washers out myself with a stanley knife though - would be perfect for my use and pretty easy to put together.

Is that not viable?

If it is, does anyone have any suggestions as to where to source the rubber (and what type I would need)?

[youngsyr]

mercfunder said:

Contact any of the companies that fabricate hoses, they should have rubber sheet calendered to the right thicknkess and will be able to cure them off in an autoclave.

Try these guys: http://www.indicorubber.co.uk/

Thanks, I'll drop them a line.

[mercfunder]

youngsyr said:

Thanks for the tips all - I was kind of hoping to just be able to pick up an A4 sized sheet of 2mm thick rubber and then just cut the washers out myself with a stanley knife though - would be perfect for my use and pretty easy to put together.

Is that not viable?

If it is, does anyone have any suggestions as to where to source the rubber (and what type I would need)?

You would probably be best going for a "nitrile" or "EPDM" depending on the temperatures it will exposed to.

[kev b]

How about scrounging an old HGV inner tube from your local tyre place?

[Tunku]

http://www.shopwiki.co.uk/_Silicone+Baking+Sheet/M...

[Buzz word]

I'd just get a bit of plastic from anywhere as it will be easier to find. Use an old cd, number plate whatever and fix it on. I don't think an airtight seal between the air feed and filter shield will be important as there will not be a perfect seal anythere else. A close fit to limit hot air being drawn in would be good but a perfect seal seems too far. I would be more concerned about making sure when it passed through the shield it was on a surface that was not sharp enough to cut the inlet pipe, if plastic, over time.

[Uhura fighter]

Might have something in a hoover, try the local repair shop.

[youngsyr]

Tunku said:

http://www.shopwiki.co.uk/_Silicone+Baking+Sheet/M...

Awesome, that will do nicely and you can pick up black ones on Ebay for £3 delivered. Thanks very much!

[youngsyr]

mercfunder said:

youngsyr said:

Thanks for the tips all - I was kind of hoping to just be able to pick up an A4 sized sheet of 2mm thick rubber and then just cut the washers out myself with a stanley knife though - would be perfect for my use and pretty easy to put together.

Is that not viable?

If it is, does anyone have any suggestions as to where to source the rubber (and what type I would need)?

You would probably be best going for a "nitrile" or "EPDM" depending on the temperatures it will exposed to.

Thanks, I'm going to give the silicone baking mats a go, they're only 1mm, but I assume they'll be slightly stiffer than rubber and they're rated to 240*C, so being in the engine bay shouldn't be a problem unless the whole lot goes up in smoke!

[-Pete-]

You do know the whole point of silicone backing sheets is that nothing will stick to them. Including glue...

[youngsyr]

-Pete- said:

You do know the whole point of silicone backing sheets is that nothing will stick to them. Including glue...

Whoops - hadn't considered that! Will instant gasket not adhere to them - it doesn't need to "glue" the pipe in place, just seal the washers to the duct?

If not, at least teh OH has an early Xmas present!!

[-Pete-]

youngsyr said:

-Pete- said:

You do know the whole point of silicone backing sheets is that nothing will stick to them. Including glue...

Whoops - hadn't considered that! Will instant gasket not adhere to them - it doesn't need to "glue" the pipe in place, just seal the washers to the duct?

If not, at least the OH has an early Xmas present!!

Happy Christmas it is, then! They're actually really good in the bottom of ovens!

[A911DOM]

would you not find a suitable rubber washer of sorts (in this type of diameter) at a local drain / plastics / kitchen or bathroom / diy supplier?

I cant think of the right term now - but they also have the adaptors that size up or down from a certain width of pipe to fix it to a different width of pipe no?

[youngsyr]

A911DOM said:

would you not find a suitable rubber washer of sorts (in this type of diameter) at a local drain / plastics / kitchen or bathroom / diy supplier?

I cant think of the right term now - but they also have the adaptors that size up or down from a certain width of pipe to fix it to a different width of pipe no?

I suspect that you're thinking of reducers and thanks for the tip, but I'd rather avoid using a reducer if at all possible. The washer idea seems to be the simplest solution, but it's a case of getting the correct material to make them out of.

I've scanned all the usual suspects for someone that already makes the correct size rubber washer (110m OD/70mm ID) but with no success.