Focus One speed changer and cover plate

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Armbored
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Focus One speed changer and cover plate

Post by Armbored » 17 Oct 2016 14:00

Hi all,
I wonder if someone can give a guidance on a couple of aspects of the Focus One I am struggling with.

Number one is the speed changer. There seems to be a couple of versions of this going about; one with a pair of wire fingers and the other, which has a loop of wire that the belt runs between (mine). The knurled plunger on top of the cover moves the springy wire either up for 33 or down for 45. In essence, the mechanism works, but rubs against the belt. When you pull the plunger up for 33, the knurled knob does not stay up, but collapses, and with it so does the wire loop, which then rubs against the belt. I have fiddled about with the wire trying to bend it subtly to make it work better but when you get it perfect for 33, as soon as you select 45, the belt starts rubbing against the loop. Here is a question; should the plunger be able to support itself on it's shaft, after you pull it up? Because mine is just collapsing due to gravity, despite there being what seems a spring inside. Any thoughts would be welcome!

Number two query is about the location of the cover plate. I have seen plenty photos of other Focus Ones where the speed change plunger is located centrally in the hole created for it. However, on mine, it is out of centre and almost touching the edge of the Perspex. Try as I may, I cannot line up the hole and plunger correctly, is there a secret? I know that the three motor mounts can be adjusted to make the pulley sit level, but can't see how they would affect the correct seating of the Perspex cover, relative to the speed changer. Am I missing something?!

Any help would be greatly appreciated, thanks.
Mike

Armbored
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Re: Focus One speed changer and cover plate

Post by Armbored » 18 Oct 2016 20:36

For anyone who is interested; I managed to work out the number two query. The triangular plastic plate the motor is mounted to is adjustable once you loosen the three dome shaped nuts, and it's just a case of trial and error of moving it around until the knurled plunger sits in the centre of the Perspex cover once it's laid on top.

Mike

Officerpup

Re: Focus One speed changer and cover plate

Post by Officerpup » 19 Oct 2016 09:58

I don't think there's a spring in the speed changer, you simply lift it up to pull the belt onto the other pulley and vice-versa . . .

And it's a plain 'knob' on mine, with a single groove, the knurling being left for the On/Off switch . . .

Is the issue still there now you've adjusted the motor-board in relation to the 'cover'?

Armbored
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Posts: 109
Joined: 19 Jan 2015 18:14
Location: Aberdeen, Scotland

Re: Focus One speed changer and cover plate

Post by Armbored » 19 Oct 2016 10:20

Hi there,
Yes you are right it's a plain knob for the speed change, I was getting confused with the on/off switch, sorry.
I finished working on this last night, you're right again there is no spring inside, just the wire that gives it the springiness. The knob doesn't stay 'up' though, which is the frustrating bit; it sinks and makes it very difficult to achieve a point at which the belt can run at both speeds without scuffing against the wire guide fingers. After much trial, I did manage to get it right, but it took me a while, with much fiddling. I think it would be preferable for the knob to have some resistance on the shaft, so that the actual wire guides were more in line with the belt on the relevant pulley.

Thanks
Mike

Officerpup

Re: Focus One speed changer and cover plate

Post by Officerpup » 19 Oct 2016 13:52

I'll have to have a squint at mine - can't say it's ever been a problem in the near 30 years I've had it!

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