MakeEverything
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| posted on 22/12/11 at 07:41 PM |
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Sequential conversion
Sequential conversion
Ok, I know this has been discussed to death on the forum previously, but I thought I would see if I can get an up to date idea on what is possible.
I know Jack Knight did a conversion (http://www.jackknight.co.uk/press_re...%20release.pdf) but is it;
A) still available
B) any good
C) cost efficient
D) the only one on the market?
I'm looking to play with my spare UN1 shortly.
Kindest Regards,
Richard.
...You can make it foolProof, but youll never make it Idiot Proof!...
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Mr C
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| posted on 22/12/11 at 09:49 PM |
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Jeremy and myself have been looking for the past two years for a sequential system for our projects, nothing seems to hit the mark though. The closest
is this conversion that you may or may not have seen before.
linkage
It seems a lot of money though especially when you still need to use the clutch, though maybe we are expecting too much.
Apologies if this is old news.
Girl walks into a bar and asks for a double entendre, so the barman gave her one
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Simon
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| posted on 22/12/11 at 10:10 PM |
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Big Money
Not a UN1, but should give you an idea on potential pricing
ATB
Simon
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MakeEverything
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| posted on 22/12/11 at 10:15 PM |
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Thanks mr c. I haven't seen that before, but they don't have anything compatible with the UN1. I was hoping for just a stick driven
sequential shift and manual clutch. Nothin special, just simple sequential gears.
Thanks for the post tho. Good luck in your search too.
[Edited on 22-12-11 by MakeEverything]
Kindest Regards,
Richard.
...You can make it foolProof, but youll never make it Idiot Proof!...
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MakeEverything
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| posted on 22/12/11 at 10:16 PM |
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quote:
Originally posted by Simon
Big Money
Not a UN1, but should give you an idea on potential pricing
ATB
Simon
Thanks Simon, hence looking for a conversion rather than a full box. I've seen a sequential UN1 for 3500.00, but I'm not that worried!!
Kindest Regards,
Richard.
...You can make it foolProof, but youll never make it Idiot Proof!...
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Xtreme Kermit
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| posted on 23/12/11 at 12:03 PM |
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Hmmm. Interesting idea on the Mastershift, being able the stack the gear changes by multiple pushes on the buttons, then activating the changes by
using the clutch.
Sounds vaguely familiar...
Oh yes, that's it! Bus pre-selector 
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MakeEverything
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| posted on 23/12/11 at 01:12 PM |
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quote:
Originally posted by Xtreme Kermit
Hmmm. Interesting idea on the Mastershift, being able the stack the gear changes by multiple pushes on the buttons, then activating the changes by
using the clutch.
Sounds vaguely familiar...
Oh yes, that's it! Bus pre-selector
That is interesting. I wonder if there is a module on a bus somewhere that could be adopted?
Kindest Regards,
Richard.
...You can make it foolProof, but youll never make it Idiot Proof!...
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MikeRJ
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| posted on 23/12/11 at 03:22 PM |
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Surely a sequential conversion for a standard sychro box is a waste of time, it certainly won't give faster shifts?
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Xtreme Kermit
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| posted on 23/12/11 at 10:46 PM |
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You could say the same thing about putting lotus Carlton running gear into an early senator shell.
This does not stop it happening or people enjoying the challenge.
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v8kid
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| posted on 24/12/11 at 10:28 AM |
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I don't think the control box is the problem. It should be straightforward to use a processor linked to speed and engine revs so that when the
clutch is engaged it will select up or down. Not quicker as sutch but it gives you less to think about in the heat of the moment.
Also it would overcome loads of problems with mechanical lnkages on rear engined cars which tend to be slow.
Looks as if mastershift are using 1/4 up servos the bit I can't work out is how do they select neutral when shifting from 2 to 3?
Is it worth collaborating on the un1 shift to arrive at a locost solution?
You'd be surprised how quickly the sales people at B&Q try and assist you after ignoring you for the past 15 minutes when you try and start a
chainsaw
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MakeEverything
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| posted on 24/12/11 at 11:02 AM |
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quote:
Originally posted by Xtreme Kermit
You could say the same thing about putting lotus Carlton running gear into an early senator shell.
This does not stop it happening or people enjoying the challenge.
Thanks Ian, I agree. Once the mechanism is sortd, changing the gears and shafts is a relatively simple task???
Kindest Regards,
Richard.
...You can make it foolProof, but youll never make it Idiot Proof!...
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Xtreme Kermit
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| posted on 24/12/11 at 11:43 AM |
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quote:
Originally posted by v8kid
I don't think the control box is the problem. It should be straightforward to use a processor linked to speed and engine revs so that when the
clutch is engaged it will select up or down. Not quicker as sutch but it gives you less to think about in the heat of the moment.
Also it would overcome loads of problems with mechanical lnkages on rear engined cars which tend to be slow.
Looks as if mastershift are using 1/4 up servos the bit I can't work out is how do they select neutral when shifting from 2 to 3?
Is it worth collaborating on the un1 shift to arrive at a locost solution?
Presumably they have a servo for the front to back movements and another side to side ones.
Second to third would be a sequence of 50% movement on the fore/aft servo followed by a side to side kick finished off with another fore/aft shove.
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v8kid
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| posted on 24/12/11 at 03:54 PM |
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Yes but how do they sense neutral that's the crux
You'd be surprised how quickly the sales people at B&Q try and assist you after ignoring you for the past 15 minutes when you try and start a
chainsaw
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Xtreme Kermit
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| posted on 24/12/11 at 05:39 PM |
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I see where you are coming from.
Do you need to though?
If you can program in three for and aft positions, you don't need to run with feedback from the gearbox, just the positioning servos.
position 1 = (1,3,5)
Position 2 = neutral
Position 3 = (2,4,6)
Of course reverse is in there somewhere too...
And the left/right servo would have known positions for
Reverse
1,2
3,4
5,6
Does that make sense?
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v8kid
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| posted on 25/12/11 at 07:37 AM |
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Yup but there has to be a reference position where the servo starts from. Say you set it up in first and then move x to neutral and a further y to
second. With all the slop, backlash, vibration the setting can move and second will not be fully engaged. Worse what happens if the variation is so
great that coming back from second to neutral to go to third and it misses neutral and the servo is pulling across the gate in vain?
Having neutral as the default position overcomes this and allows the actuator linkage to be spring loaded ensuring that the gears are rammed home.
I'm not sure now I'll have to ponder over it but I think Crimbo duties are calling as I hear the kids stirring 
Cheers!
You'd be surprised how quickly the sales people at B&Q try and assist you after ignoring you for the past 15 minutes when you try and start a
chainsaw
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Xtreme Kermit
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| posted on 25/12/11 at 01:27 PM |
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Could it be done with limit switches? Use neutral as centre and then drive until the appropriate limit switch is hit? Could get real messy.
Maybe a PLC with a set of stepper motors is the way. You would probably have to calibrate it every so often , but using neutral as a centre spot, turn
N timess to reach a goal position...
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Paul Turner
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| posted on 25/12/11 at 02:38 PM |
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Sorry if I am missing something but even if you could automate the change action with any number of motors etc you would still have to depress the
clutch manually unless you could somehow incororate an hydraulic pump to do that which would surely make the whole thing incredibly complicated. Is
this why all the mainstream manufacturers have not developed a system like this for production cars.
Sounds great and I love these left field ideas that people get working but how much hassle would it be.
With regards to the pre-selector box my dad had such a beastie in a Lancester when I was but a tiny brat. He loved it but a lack of spares for the
diff mean't the car got scrapped, the wire wheels ended up on a cement mixer!!!! one of the solid drieshafts is still in garage having been
turned into a long chisel, the splines are still just visible. The Lancester had what dad calls a "fluid flywheel" guess the ancient
equivalent of a Torque converter, don't know any more than that. Pre war ERA grand prix cars used the pre-selector box, still love watching them
at historic meetings, seeing the drivers at work (especially at Cadwell) and noticing them moving the gear selector as they come onto the strait and
depressing the clutch several seconds later to engage the gear brings back fond memories.
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v8kid
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| posted on 25/12/11 at 02:45 PM |
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How fast can stepper motors turn? 1 to 2 would take 32 turns assuming 16 tpi rod and 135 oz in stepper to give 135 lbf to match mastershift specs.
Assuming .5 sec shift that's 3840 rpm at rated torque. Can steppers do this?
You'd be surprised how quickly the sales people at B&Q try and assist you after ignoring you for the past 15 minutes when you try and start a
chainsaw
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Xtreme Kermit
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| posted on 25/12/11 at 05:56 PM |
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Hmmm When you put it like that, it's an awfull lot of work to do in 0.5 seconds.
Are there any other alternatives?
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phelpsa
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| posted on 25/12/11 at 06:02 PM |
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quote:
Originally posted by Paul Turner
Is this why all the mainstream manufacturers have not developed a system like this for production cars.
Oh but they have! Citroen's sensodrive system works in exactly this way.
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MikeRJ
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| posted on 25/12/11 at 06:33 PM |
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quote:
Originally posted by phelpsa
quote:
Originally posted by Paul Turner
Is this why all the mainstream manufacturers have not developed a system like this for production cars.
Oh but they have! Citroen's sensodrive system works in exactly this way.
So have Smart and some Fiats also had a robotised manual box. They all share a common theme, they are slow to change gear. They also have a history
of being unreliable. These robotised boxes use a proper selector drum like a bike gearbox however, which makes things much simpler - using a
mechanism to move an H gate will be more complex and as a result more unreliable and slower. Sorry to be negative, but I simply can't see any
benefits for putting work into this, unless you specifically need a robotised manual box (e.g. through disability etc.).
[Edited on 25/12/11 by MikeRJ]
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phelpsa
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| posted on 25/12/11 at 11:27 PM |
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quote:
Originally posted by MikeRJ
quote:
Originally posted by phelpsa
quote:
Originally posted by Paul Turner
Is this why all the mainstream manufacturers have not developed a system like this for production cars.
Oh but they have! Citroen's sensodrive system works in exactly this way.
So have Smart and some Fiats also had a robotised manual box. They all share a common theme, they are slow to change gear. They also have a history
of being unreliable. These robotised boxes use a proper selector drum like a bike gearbox however, which makes things much simpler - using a
mechanism to move an H gate will be more complex and as a result more unreliable and slower. Sorry to be negative, but I simply can't see any
benefits for putting work into this, unless you specifically need a robotised manual box (e.g. through disability etc.).
[Edited on 25/12/11 by MikeRJ]
Interesting! Take gearbox, de-robotize, you have what you want... sequential box! You'd still have to use the clutch though as I presume
they're still synchro.
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owelly
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| posted on 26/12/11 at 09:29 AM |
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Alfas Selespeed uses a manual box with a hydraulic flibberit mounted on the top to select the gears and operate the clutch. Worth looking into?
http://www.ppcmag.co.uk
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MakeEverything
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| posted on 26/12/11 at 10:39 AM |
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Thanks for all the comments and support fellas, some good discussion.
The gears don't necessarily need t be h pattern, s was wondering if the shafts and gear arrange,ents could be modified to make them sequential
as well. Solenoid actuation is relatively fundamental, but the controller / PLC would need some thought.
Kindest Regards,
Richard.
...You can make it foolProof, but youll never make it Idiot Proof!...
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l0rd
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| posted on 26/12/11 at 10:42 AM |
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I believe 3 actuators should be able to do the job
2 for changing the gears and one for the clutch.
Programming all these shouldn't be a big issue. To make things easier, i would have 7 buttons on the steering wheel one for every gear.
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