Welding Tips and Tricks

As many of you know, I lost my left leg to stupidity back in October. I drove my 240sx for the first time on Thursday after replacing the power steering pressure hose, and drove it around smiling like an idiot Thursday-Saturday.
Then, being that I've always been in trouble with the law due to my driving habits, I got a little flustered after the local cop circled the block the 3rd time as I was idling in my driveway verifying that the temperature would come down after the fans kicked on again. So, when I got out of my car Saturday night (had just finished wiring in different headlights so it was my first night time drive) I forgot to put my leg back in "walk mode" and fell and broke my foot... for the 3rd time since I've been at school since February

This left me in a frustrated position, because not only do I have to use crutches at school and work until I can get a new ankle unit it, I can't drive my car! I don't know if any of you can relate to the feeling of elation that I had, but believe me, it %$#& SUCKS knowing that the car is drive able, but I can't drive it due to not having my prosthetic.

I was sitting at work today talking with my tech and bitching about the local PD not having anything better to do than troll me because of the aftermarket tail lights (probably more so the lack of license plate light than the tail lights, but whatever ) and I had an epiphany! I had been talking about doing a hand clutch for a long time, but realized I could drive my car without one. This, as you can only imagine, has a tendency to be a little sketchy because I have to rely on consistent movement speeds which doesn't always happen for one reason or another. Plus, if I piss Braehill off and he takes the Suzuki back, I'd be totally and royally %$#& if something were to happen to my leg if I didn't have an alternative means of transportation, or a hand clutch.

This brings me to the real question. How, in practice and/or theory, would you guys go about modifying a vehicle to work with a hand clutch? I have access to lathes, mills, welders, shop tools, SolidWorks, and access to 3 of the best fabricators I've ever met. My first thought was to go electrical, but the spec sheets I can find for servo's and linear actuators do not lead me to believe that they can provide enough OOMPH with enough speed, as that is the major tradeoff. Teeing into the power steering would also probably work, but I'm not sure how you would divert fluid after application of the clutch to modulate release... I.E. application would be easy, having a dynamic release would I think be the difficult part. Air pressure is another option, but again, I'm not sure how to modulate application/release so as to provide a smooth action, yet still be able to just dump it all at once for drifting

Any input on the matter is greatly appreciated!

Sam

I'm very familiar with these cars (asuming you have put an sr20 in it)
First thing I would be doing is sorcing a clutch booster (just like a brake booster) from a 300zx (fairlady) or a r32 gtr (not sure if the 33 or 34 where equipped with one)
If your running any more then relatively stock power your next step would be hit the gym hard!!!
As anymore then a stock clutch will give you grief beyond your wildest dreams.
Or you could bypass all that and get a dog box.
You will still need clutch for take off but you can do the ups shift clutchless and with a little practice also downshift clutchless

Hope this helps ya a bit.

I can (could I guess it would be since it is now past tense) go up and down in anything with no clutch. However, I was unaware that Z&R32's had a vacuum booster for the clutch. That is interesting. I have no issues pressing the clutch in with the knee, the biggest problem is that I hit the steering wheel on clutch release, and sometimes the column surround on the bottom of the dash where the cruise and headlight buttons are on application. My issue is that if I break something on my leg, or can't wear it due to skin breakdown I would be stuck without a ride. I need to retrofit a hand clutch so that I can drive the car without needing to wear the leg if I don't want to

This one is pretty cool

http://youtu.be/oiXnVl_KZ70

Only problem is its $2700-3500 :/

GreinTime wrote:Only problem is its $2700-3500 :/

That would definitely be a problem....

You could just put in an automatic that is what i would personally do. Nothing sucks more than being stranded.

%$#&. That. That would be admitting defeat!

Sam,
An old friend of mine lost his leg jut below the left knee.
He rigged a clutch lever in his old truck that was knee operated.
You got in and it folded down from the dash and it sat outside of his left knee.
He kept his prosthetic foot planted flat on the floorboard and would just swing
his knee towards the door to disengage the clutch. He drove the piss out of that
old truck too!

Hhmm being in Australia and our car being right hand drive and USA left hand drive just makes things harder (for me) to work out properly in my head.
And my s13 is full of junk at (not going to remove it soon )
Would love it if you lived near by as it sounds like an engineering challenge totally out of the box compared to all the other mods I have done to the s13-15 nissans.

I'm sorry I'm not familiar with the car so this won't work if the release is concentric cylinder - but cable or external cylinder could be adapted - try to find the clutch actuating chamber from a Volvo car with belt drive - I think they're 300 series ( funny thing with Renault engine up front with the clutch plus fluid flywheel - aluminum prop driving a diff with belt drive variable speed onto back wheels ) basically it looks like a truck air brake chamber but works off engine vacuum - if you can connect that to the clutch release arm all you need is vacuum to operate - simplest thing I can thing of on spur of the moment is find an truck parking brake valve & remove the detent so it will not lock in park position - with a bit of ingenuity it could be mounted to the shifter direct or remote using a bowden cable & motorcycle hand lever - this could then control vacuum to the cylinder - with adequate size pipe it would work plenty fast enough - or at least it does in a Volvo ! - hope this makes sense - it's doable & basically junkyard price parts.

Corvette, Ford ranger, etc
or
http://www.summitracing.com/search?Sort ... c%20clutch
or
http://www.speedwaymotors.com/Search?qu ... utch%20kit

mount master and use hand lever

http://home.comcast.net/~racerz85/1%20005.jpg

http://www.krausmotorco.com/images/bikes-phoenix-6.jpg

Rick, I are confuzzled!

Seriously though, I don't know if its my phone being stupid or what, but those links only take me to a general search for hydraulic on speedway and summit both :/ and Brian, that is something I will have to look into. I have a friend that Is a Volvo fanatic and will know what you are talking about!

Drifta-- I wish I was in Australia too some days my friend!

GreinTime wrote:%$#&. That. That would be admitting defeat!

[x] Like


Juicy boxes are for kids and elderly.


I was lucky enough to keep my leg after getting the femoral artery crushed back in 88. I wound up buying an automatic (shudders) and got rid of it as soon as I could mash a pedal again. Aside from a competition vehicle, that's the only one i ever owned ever.

SO I get the grief and desire. My thought is that it shouldn't be any STEP for a STEPPER!

Hydraulic clutch master can be mounted anywhere and actuated any way. For an idea of the flexibility of hydraulic systems look at sports care racing setups where the balance between front/rear braking is controlled by the position of the rod/linkage which activates 2 separate master cylinders with one foot pedal.

I'm thinking a longer lever would bring forces down to reasonable levels, and you can always throw it out of gear and relax your arm, same as with a foot pedal.

I'm thinking the biggest hurdle will be mounting all the stuff, which has been done before--so try to find a few hand-control vehicles to examine for ideas. Then just adapt/cut/paste the ideas ...in metal

Southbend Clutch is the greatest clutch making company (that i've ever done repeat business with). They are experts at high-horsepower/torque applications paying full attention to force requirements (1000# of torque my truck). I'll bet you anything they can help out or direct you to the proper clutch folks IF THAT is even necessary.

I don't know what they know about hand actuation, but clutches...them they know:

http://www.dxdracingclutches.com/

I'm thinking store-bought hand controls will be silly expensive and that one could very well fab up something that suits his own needs better for less.

I don't necessarily need hand controls in the traditional sense, just trying to figure out a way to do this effectively. It doesn't have to be aesthetic (yet) but it has to function. I've talked to the guys over at South Bend years ago and they are very knowledgeable. However, I am not in need of a new clutch yet, although at the rate I've been slipping the bejeezus out of it because I hit the steering wheel I will soon

these type do not use traditional pivot forks. the actuator/throw out bearing slids over input shaft bearing support and expand/extends to press againist pressure plate for release. They are universal type. does away with complicated mechanical linkage.
used in many racing/off road applications, custom builds

Sam,

This is the kind of challenge I love. I already have ideas brewing.

I sense a "by wire" solution, with a clutch lever just as on a motorcycle. That part is simple... It's the feedback, so you sense what you're doing that's the challenge....

(Rusty gears turning and creaking.)

Steve S

rick9345 wrote:these type do not use traditional pivot forks. the actuator/throw out bearing slids over input shaft bearing support and expand/extends to press againist pressure plate for release. They are universal type. does away with complicated mechanical linkage.
used in many racing/off road applications, custom builds

yeah, that's what i'm talking about. lever/leverage to make appropriate hand activation pressures (what can't be addressed by master/clutch release cylinder sizing).

Ohh I gotcha haha. It was the Ford Ranger one that got me, I didn't realize that they used a hydraulic throwout bearing instead of a slave cylinder and fork

Sam,
I too have some ideas, will post up tomorrow.
- Jonathan

Too bad you couldn't rig up a single rocker pedal for both throttle and clutch. Toe for gas, heel for clutch.

That would be kind of cool haha.

Drifta-X raises a good point in the fact that Nissan uses a vacuum booster for the clutch on some of their vehicles (not that I can find one on the interwebz, and a new one is $345 from Nissan.). If using a booster like that, I don't see why there would be any issue using a large bore master cylinder on the back side to reduce the amount of movement needed to engage/disengage the clutch, and uses a motorcycle master cylinder and small slave cylinder to actuate the pushrod on the pass. Compartment side of the booster. I just have to figure out part numbers and overall cost.

I look forward to hearing the rest of your ideas!

Um... This is going to sound "out there", but I did it.

When I had an immobilized leg and a 5-speed, I rigged an auxillary throttle rather than a remote clutch. I used the cruise-control loop on the throttle-body and a cable to a bicycle brake handle attached to my shifter. It gave me about half-throttle at the handle. That way I could use the brake and clutch with one leg, and the aux throttle let me take off, shift, and then settle my foot on the gas for cruise.

Steve S

This car currently isn't my primary means of transportation, so this doesn't need to happen right now, and I don't want to just make something work temporarily. Hopefully it is never my primary means of transportation, because as much as I like it, if I don't end up at a tuner shop or something, it doesn't look very professional to show up in a slammed 240sx

In all reality, I SHOULD be trying to make a permanent solution that can be retrofitted to anything, and potentially market it to the public. A friend I've made through Facebook has a product that he wants to bring to the market, but lacks the capital to mass produce until he can manage to present a proposal to investors.

In a perfect world, it would be an electric over hydraulic master cylinder/clutch actuator that uses variable resistance from a linear potentiometer to apply the clutch. However, I personally don't have the electrical knowledge to undertake such a task as this, and would have to rely on store bought components to make it work.