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#Post#: 6180--------------------------------------------------
Source of coil springs, rack and pinion anyone tried it?
DIR By: Jimr1999
Date: March 30, 2022, 1:12 am
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Just been surfing YouTube and found this
HTML https://www.youtube.com/watch?v=03BVhYuYZAk
Has anyone made a rack out of one of these gears, we come across
so many broken ones that just get replaced, it could be a source
of bits???
#Post#: 6181--------------------------------------------------
Re: Sorce of coil springs, rack and pinion anyone tried it?
DIR By: David F-R
Date: March 30, 2022, 2:10 am
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How ingenious, a ready made rack and pinion. Good find Jim.
£30 new from Screwfix so they will be cheaper somewhere.
#Post#: 6182--------------------------------------------------
Re: Sorce of coil springs, rack and pinion anyone tried it?
DIR By: David F-R
Date: March 30, 2022, 2:35 am
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--- Quote from: David F-R link ---
>
> £30 new from Screwfix so they will be cheaper somewhere.
>
--- End Quote ---
There are loads on ebay from£13 new. Might just get one to play
with.
#Post#: 6183--------------------------------------------------
Re: Source of coil springs, rack and pinion anyone tried it?
DIR By: Jimr1999
Date: March 30, 2022, 2:42 am
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Just got a dead one from work, I will spanner it to bits this
weekend and see what the travel is
I think I may still get a piman arm on the first kart for
simplicity unless this is a no brainer
#Post#: 6185--------------------------------------------------
Re: Source of coil springs, rack and pinion anyone tried it?
DIR By: Jimr1999
Date: March 30, 2022, 1:43 pm
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OK.
Just spannered a closer to bits. The one I have moves about 40mm
lock to lock in approximately 240 degrees of pinion rotation The
spring that came out of it looks like 142 uncompressed, 30 OD
and a 4mm wire coil
Not sure 40mm of travel is sufficient ???
#Post#: 6186--------------------------------------------------
Re: Source of coil springs, rack and pinion anyone tried it?
DIR By: David F-R
Date: March 30, 2022, 2:03 pm
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I'm inclined to agree Jim. I think 100mm would be nearer the
mark.
Good for you giving it a try though.
I have looked at various racks and pinions for sale with a view
to assembling a simple box, but for now I'm sticking with the
standard simple swinging arm system.
#Post#: 6187--------------------------------------------------
Re: Source of coil springs, rack and pinion anyone tried it?
DIR By: Jimr1999
Date: March 30, 2022, 2:15 pm
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I think the attachment arm has promise on this one as it has a
serrated circle of interlocking teeth at about 10 degree
intervals for adjustment and a natural pitman arm from the
closer lever. I might be able to use bits of it yet. The other
option I to drill holes further up the arm from the king pin to
increase the effect of the travel of the rack
#Post#: 6189--------------------------------------------------
Re: Source of coil springs, rack and pinion anyone tried it?
DIR By: Jimr1999
Date: March 30, 2022, 4:02 pm
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Ok, doing some maths, I would have to site the attachment point
of the track rod end 47 mm from the centre of the king pin to
achieve an average of 25 degrees of steering either side of
centre lock to lock on the 40mm travel of the rack and pinion
gear in the door closer. This would be accomplished with about
240 degrees of steering wheel turn... How far out am I?
#Post#: 6201--------------------------------------------------
Re: Source of coil springs, rack and pinion anyone tried it?
DIR By: Jimr1999
Date: April 1, 2022, 4:35 am
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Stripped the scrap "Geze 2000" German opener to see its guts.
See pictures
It is a very solid bit of engineering with next to no lash, The
pinion is on needle bearings both sides, the pinion has 41mm
available free movement and the rack cylinder looks like it has
plenty good metal either end to attach arms somehow.
I am NOT going to use this as a steering rack on this Kart, I am
going down the Pitman arm route after a couple of conversations
and some reading in fora. The spring is available if anyone
needs one, I will post UK.
The lever arm was what I started looking at when I was looking
for a ready made Pitman arm and may be used as the splined end
might give me a bit of adjustment to align the steering wheel if
I mess up.
If anyone is interested, I have one of the site guys on the
lookout for different dead ones when we replace them and I might
look at the comparative rack lengths from different brands. To
achieve clearance with this short a throw on the rack would have
proved difficult at the steering arm end.
If anyone does go down this route, I would be interested to hear
about the results.
#Post#: 6746--------------------------------------------------
Re: Source of coil springs, rack and pinion anyone tried it?
DIR By: Jimr1999
Date: May 8, 2022, 8:21 am
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... To follow on if anyone has any interest and for the sake of
experimentation. I got a couple more dead closers from the site
lads and spannered them to bits.
First up was a cheap Ebay Chinese closer. it had had a hard life
by the look of the oil. the bearings were not of any note and
the mechanism for the rack threw 41mm in about 2400 of turn. It
could be adapted to a rack with a little ingenuity and a length
of threaded bar. The rack part is on the outside of the
cylinder, no lash was felt in the mechanism.
Second up was a Dorma ts73v
The oil was clean and the bearings were the needle type like the
Geze.
Again this threw 43mm in 2500 total but not all of it is
available with the end cap on, a little light fettling would
free up the movement. Again adaptable to a rack. The rack was on
the inside of the cylinder like the Geze one. No lash was
present in the mechanism.
Both of these like the Geze before would require placing the
track rod end nearer the king pin on a Gemini arm, and as I have
said before, I am not looking for a rack on the BSA (I have a
Pitman arm now) but who knows where I will go on the next one.
I also got 2 springs from the Chinese one and a one spring
arrangement from the Dorma.
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