undercarriage compression rubbers

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JJennings
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Joined: Thu Jan 03, 2013 9:25 am

undercarriage compression rubbers

Post by JJennings » Sat Nov 26, 2016 10:15 pm

Hi,
Can anyone help?
I`m rebuilding a moth minor and like many types it has compression rubbers in the sliding tube legs.
Where do Jodel, condor owners etc get replacement compression rubbers made.
I have the drawing (although the spec of rubber is from 1938!) and original samples.
Prepared to get a mould made but need firm with some experience of similar work.
Many thanks,
John
John Jennings
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coxargus
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Re: undercarriage compression rubbers

Post by coxargus » Sat Nov 26, 2016 11:16 pm

I might be teaching grandmother to suck eggs but have you tried the Moth club for information - under 'Service register' - then 'Rubber mouldings and extrusions'?
Frank Cox
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JJennings
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Re: undercarriage compression rubbers

Post by JJennings » Sun Nov 27, 2016 11:25 am

coxargus wrote:have you tried the Moth club for information - under 'Service register'
Unfortunately it doesn`t seem to be that simple.
Some compression rubbers have been made (for moths) that are not of the required hardness.

Just thought it was worth asking guys who operate types with similar u/c and a/c weight.
John
John Jennings
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TRAZZELL
Posts: 137
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Re: undercarriage compression rubbers

Post by TRAZZELL » Sun Nov 27, 2016 8:52 pm

I've had some polyurethane rubber rods made with 55 Shore hardness (as spec) for my Menestrel project. 40mm dia x 300mm long then sliced up on a bandsaw into blocks and through drilled 8mm for the locating pins. We're a while away from trying them out though!

Tony Razzell
Tony Razzell
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Nick Allen
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Re: undercarriage compression rubbers

Post by Nick Allen » Mon Nov 28, 2016 10:11 am

When we refurbished the undercarriage of our Jodel D9 what came out looked very, very much like rubber doorstops!

We replaced them with natural rubber bobbins, from here:

http://www.wdsltd.co.uk/product/4068/fe ... p-wds-714/

We were advised by a Jodel expert that 60 shore was the right grade, and we compressed the stack about 20% in situ.

Brian Hope
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Re: undercarriage compression rubbers

Post by Brian Hope » Mon Nov 28, 2016 3:45 pm

Hi John. I guess most Jodel owners bought their undercarriage rubbers from Pete Smoothy at Airworld UK. Although he's closing the business you can still get contact phone numbers by googling Airworld UK.
I don't know whether Pete bought the rubbers in from France already made, or whether he had them manufactured, it would be worth asking him though, he's a helpful sort of chap.
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TRAZZELL
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Re: undercarriage compression rubbers

Post by TRAZZELL » Mon Nov 28, 2016 9:16 pm

I paid about £32+VAT per 300mm length from Direct Plastics so pretty good value I thought. I did consider making them myself ( they are cast from a two part liquid polyurethane) but the bandsaw technique seemed to work well enough. You can buy Durometers pretty cheaply which would allow you to test a sample.

Tony Razzell
Tony Razzell
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JJennings
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Re: undercarriage compression rubbers

Post by JJennings » Thu Dec 01, 2016 11:20 am

Thanks for the input chaps.

A few good ideas to follow up.
It`s very easy to beaver away for years in the "shed" inventing lots of wheels as you go.
Best
J.J.
John Jennings
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Gavin Bell
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Re: undercarriage compression rubbers

Post by Gavin Bell » Sat Dec 31, 2016 6:24 pm

Bradford Rubber have made some for me in the past. Give them a simple drawing and the required shore hardness. Turnaround about 10 to 15 days

Gavin
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JJennings
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Re: undercarriage compression rubbers

Post by JJennings » Sat Jan 07, 2017 3:44 pm

Thanks Gavin,
May I ask what shore hardness you went for.
Some old rubber discs I have are about shore 70 but are not original manufacturers spec.
KR
John
John Jennings
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Gavin Bell
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Location: York

Re: undercarriage compression rubbers

Post by Gavin Bell » Thu Jan 12, 2017 10:27 pm

I believe it was 60 Shore, whatever the standard Jodel spec states.

Gavin
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