Author Topic: Safe-D-Speeder planetary gear?  (Read 110 times)


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Safe-D-Speeder planetary gear?
« on: 18 Sep 22, 09:37 am »
Morning all,
what is the group think about using this...

In line in the steering column with a pitman arm steering set up to reduce effort. It has a four to one ratio so would give about one and a half turns lock to lock.
I do not intend to use this if the Pitman arm set up is to my liking when I manage to get some track time, but it is another option other than using a rack?
The Safe-D-Speeder was a thing before variable speed drills to use with masonry bits at lower speed and higher torque.
Answers and thoughts please.

« Last Edit: 18 Sep 22, 12:59 pm by Jimr1999 »
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Re: Safe-D-Speeder planetary gear?
« Reply #1 on: 18 Sep 22, 06:50 pm »
Hmmmmmm! I’m sure I’ve got one of those tucked away somewhere that came from a house clearance of a retired craft teacher… I don’t think I’ve ever taken more than a cursory look at it. Time to go digging in the shed…


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Re: Safe-D-Speeder planetary gear?
« Reply #2 on: 19 Sep 22, 07:03 am »
I’ve been thinking along similar lines ever since I saw Chris Slade’s ingenious steering reduction gear.  I had a broken cordless drill and dismantled the epicyclic gearbox at the front of that to see if it could be repurposed, but, the ratio is too high and I’m not sure it would be strong enough (and can only guesstimate the forces involved).

My target ratio is 2:1 and that’s hard to achieve with a compact epicyclic gearbox.   I stumbled  upon these: which seem ideal although new, the cost is prohibitive.

I guess you could use a higher ratio gear but then lengthen the pitman arm to reduce the number of turns lock to lock.

I’ll follow you’re experimenting with interest.

Ian F

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Re: Safe-D-Speeder planetary gear?
« Reply #3 on: 20 Sep 22, 01:12 pm »
If your looking for a 2:1 ratio then many years ago I saw a short oval racer that had two parallel steering columns with one driving the other via a timing chain and cam / cranks gears which are 2:1.