Moulding resin switch gear adapter. Part 1.

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CaptAirhead
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Moulding resin switch gear adapter. Part 1.

Postby CaptAirhead » Fri Jun 08, 2018 12:18 pm

Having decided to make a switch gear adapter for my handlebar master cylinder using my existing /7 switchgear rather than splash out 40 odd quid on a used one which will (maybe) fit, I started out by making a pattern for the adapter using placticine :-

ImageFabricating an adapter for BMW R80/7 switch gear. by Ian Beat, on Flickr

The adapter will be held in by a metal clip which will fit across the flat on the M/C onto the flat on the adapter and held in place by the existing screw.
The Switch gear will be held onto the adapter with a self tapper.

The wedge shaped adapter pattern:-

ImageFabricating an adapter for BMW R80/7 switch gear. by Ian Beat, on Flickr

Once I was happy with the pattern, the next step was to make an RTV mould so I could cast it in resin. I usually make a two piece mould in a mould box but due to the simplicity of the piece, I will merely immerse the pattern in the RTV and cut it out when set then pour in the resin from the top.

The pattern immersed in the RTV:-

ImageMaking a switch gear adapter mould. by Ian Beat, on Flickr

Once the RTV has set, I will just break the jar then remove the pattern. Although it can't be seen, the clamp is supporting a plastic sprue which will be used to pour in the resin from the top.

Next step is to fabricate a cosmetic fillet to fill the gap at the top of the switch gear....
If you don't make mistakes, then you aren't trying hard enough!

1979 BMW R80/7 (ex-Police)
2002 Yamaha Fazer 600

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Re: Moulding resin switch gear adapter. Part 2.

Postby CaptAirhead » Fri Jun 08, 2018 12:29 pm

Fitting a R80/7 switch gear to a GSPD master cylinder is not too difficult but leaves an unsightly gap at the top which must be filled because it is just ugly:-

ImageFitting a BMW R80/7 switch gear to a GSPD master cylinder. by Ian Beat, on Flickr

I decided to fabricate a cosmetic fillet to fill the gap but first I have to sculpt a pattern out of placticine:-

ImageSculpting a cosmetic fillet for BMW switch gear conversion by Ian Beat, on Flickr

That little notch at the front also helps keep the switch gear in place:-

ImageSculpting a cosmetic fillet for BMW switch gear conversion by Ian Beat, on Flickr

All I have to do now is to make a mould then cast a replica in resin. Once that is done, it can be tidied up and sanded smooth.
More to follow...!
Ian.
If you don't make mistakes, then you aren't trying hard enough!

1979 BMW R80/7 (ex-Police)
2002 Yamaha Fazer 600

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Re: Moulding resin switch gear adapter. Part 1.

Postby Galactic Greyhound » Fri Jun 08, 2018 1:19 pm

Thanks for the interesting post Ian!

Moulding/Casting is one of the Black Arts for me so any basic info on how it is done would be appreciated! :smile:
Ced.

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Re: Moulding resin switch gear adapter. Part 1.

Postby CaptAirhead » Fri Jun 08, 2018 1:37 pm

Hi Ced,

I'll post a little "how to" in due course. I'm just waiting for delivery of some instant mould which can be reused. Much simpler than RTV silicone but more suited to simple one offs. It would have been ideal for this project but I've started so I'll finish.
Ian.
If you don't make mistakes, then you aren't trying hard enough!

1979 BMW R80/7 (ex-Police)
2002 Yamaha Fazer 600

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Re: Moulding resin switch gear adapter. Part 1.

Postby Galactic Greyhound » Fri Jun 08, 2018 1:48 pm

Hi Ced,

I'll post a little "how to" in due course. I'm just waiting for delivery of some instant mould which can be reused. Much simpler than RTV silicone but more suited to simple one offs. It would have been ideal for this project but I've started so I'll finish.
Ian.

Thanks Ian - it would be appreciated! :smile:
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" - It works!

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Re: Moulding resin switch gear adapter. Part 1.

Postby bwprice100 » Fri Jun 08, 2018 4:32 pm

Looks very interesting, thanks

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Re: Moulding resin switch gear adapter. Part 1.

Postby ts » Fri Jun 08, 2018 11:04 pm

Ian, this is simply brilliant! Analysing the situation from the "what can be done" instead of "it's the wrong part" perspective is my favourite approach.

Would you consider casting another pair of switchgear adapters for my identical handlebar M/C?
Last edited by ts on Sun Jun 10, 2018 10:53 am, edited 1 time in total.
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Re: Moulding resin switch gear adapter. Part 1.

Postby CaptAirhead » Sat Jun 09, 2018 12:19 am

Ian, this is simply brilliant! Analysing the situation from the "what can be done" instead of "it's the wrong part" perspective is my favourite approac*.

Would you consider casting another pair of switchgear adapters for my identical handlebar M/C?
Hi,
Once it's all sorted, de-bugged, fettled and working as intended, it won't be any problem to cast duplicates. There should be three pieces to the kit. The securing adapter, the cosmetic piece for the top and the little cable support Gismo. I may modify the bottom securing adapter by moulding a nut into it so that the switch gear is secured by a machine screw rather than a self tapper. The jury is still out on that one. As I said, once the kit is sorted I'd be happy to send you one bearing in mind that it will only work on an identical M/C. Mine came from a '91 to '95 R100 GSPD but it may have been used on other models. I'll let you know when it's ready.
Ian.
If you don't make mistakes, then you aren't trying hard enough!

1979 BMW R80/7 (ex-Police)
2002 Yamaha Fazer 600

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Re: Moulding resin switch gear adapter. Part 3.

Postby CaptAirhead » Fri Jun 15, 2018 3:07 pm

After messing around with placticine I decided to make the pattern with Filo modelling clay because it could be baked hard in the oven and didn't distort like placticine which stayed soft. Also, Filo is available in black so gives a better impression of the final product.
I finally got a prototype which worked. It sits neatly in the recess of the master cylinder and is held firmly in place with a metal clip and machine screw:-

ImageSwitchgear adapter for BMW Airhead handlebar master cylinder by Ian Beat, on Flickr

This is the adapter in place. All that white stuff is talc to stop the clay sticking while it's still soft:-

ImageSwitchgear adapter for BMW Airhead handlebar master cylinder by Ian Beat, on Flickr

This is the switchgear attached to the M/C from the underneath. I have used a self tapper on the prototype but will modify it to take a nut and machine screw which will be more secure:-

ImageSwitchgear adapter for BMW Airhead handlebar master cylinder by Ian Beat, on Flickr

All that's left to do is to tidy it up then cast it in resin with the nut inserted and we're good to go on the adapter. Next step is to sculpt the top filler piece using the Filo clay. More to follow.
Ian.
If you don't make mistakes, then you aren't trying hard enough!

1979 BMW R80/7 (ex-Police)
2002 Yamaha Fazer 600

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Re: Moulding resin switch gear adapter. Part 1.

Postby boxerman » Fri Jun 15, 2018 3:20 pm

OK, I think I my have lost the plot with this thread...

It looks like a standard BMW M/C you've fitted - am I correct? If so, the switchgear is interchangeable and should fit exactly as on the old one.
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Re: Moulding resin switch gear adapter. Part 1.

Postby CaptAirhead » Fri Jun 15, 2018 4:31 pm

The M/C is off a GSPD . The GSPD switchgear is not compatible with my R80/7:-

ImageGSPD switchgear by Ian Beat, on Flickr

so I had to make an adapter to fit my switchgear to the new M/C. You can see the difference quite clearly here.. :-

ImageR80/7 switchgear on a GSPD master cylinder by Ian Beat, on Flickr

apart from the difference in height and shape, the screw fitting underneath is on the wrong side.. hence the adapter:-
Hope that clarifies.
Ian.
If you don't make mistakes, then you aren't trying hard enough!

1979 BMW R80/7 (ex-Police)
2002 Yamaha Fazer 600


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