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counter
01-10-2011, 11:33 PM
How u guys make provision for adjustability of pedals to accommodate drivers of different height?
I want to use square tubing with holes (inertia of this tube comes out to be higher than the round tube) in it for front bulkhead, to adjust the longitudinal movement of the pedal box. anybody have other idea in which there won't be any requirement of holes in front bulkhead....

counter
01-10-2011, 11:33 PM
How u guys make provision for adjustability of pedals to accommodate drivers of different height?
I want to use square tubing with holes (inertia of this tube comes out to be higher than the round tube) in it for front bulkhead, to adjust the longitudinal movement of the pedal box. anybody have other idea in which there won't be any requirement of holes in front bulkhead....

Simon Dingle
01-11-2011, 06:01 AM
Hi Counter,

Are you mounting the pedal box off the bulkhead then? You could mount the pedalbox from the floor rather than the bulkhead? I believe most teams mount it this way, that way you could avoid drilling holes in your bulkhead.

However, my old team hasn't used an adjustable pedalbox for a few years now. Instead we have separate seats or seat inserts for each driver. Last year we had a difference in height of about 6" (150mm) between our shortest and tallest driver and didn't have a problem.

There are a few benefits to using different seats rather than different pedal positions. Adjustability in the pedal-box usually (although not always) results in addition compliance in the mounting, also each driver having their own seat/insert set will mean the car fits them much better in more areas than just leg-room.

moose
01-11-2011, 03:51 PM
I've seen plenty of bulkheads with holes in them, its not the end of the world - just be careful when cutting those square tubes. And if the holes are sizeable it needs to be a part of your SEF, I believe. Just make sure that you don't get too close to the edges of those tubes..I don't think anyone has busted a square tube too recently, but it has happened in the past (usually from A-Arm cut-outs).

I agree with Simon as well, that mountings with pins and things have a tendency to cause pedals to have a ton of compliance if not done well. Just think through how you're doing it, and how you'd plan to prevent it from working the hole larger and larger, because there is a fair amount of force put on a 1/4" pin or whatever you choose to use, which likes to deform the hole in the steel tube.

murpia
01-12-2011, 06:38 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Simon Dingle:
However, my old team hasn't used an adjustable pedalbox for a few years now. Instead we have separate seats or seat inserts for each driver. Last year we had a difference in height of about 6" (150mm) between our shortest and tallest driver and didn't have a problem.

There are a few benefits to using different seats rather than different pedal positions. Adjustability in the pedal-box usually (although not always) results in addition compliance in the mounting, also each driver having their own seat/insert set will mean the car fits them much better in more areas than just leg-room. </div></BLOCKQUOTE>
Now the chassis template rules exist, has that opened out the scope for drivers with different leg lengths to use pedals in the same location?

With more height in the leg zone, presumably knees can go up and down easier?

Regards, Ian

billywight
01-12-2011, 01:45 PM
Simply drilling holes in a square tube and using a pin to constrain the pedals is a very bad design practice for the above listed reasons. There is a much better way to reinforce the holes, simply drill a bigger hole and weld a tube into that such that the ID of the tube you weld in is the diameter of the pin you plan to use (well, slightly larger of course). I would assume this is probably mentioned in a Carol Smith book somewhere.

Steeeeeeeeeeve
01-12-2011, 04:24 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by billywight:
Simply drilling holes in a square tube and using a pin to constrain the pedals is a very bad design practice for the above listed reasons. There is a much better way to reinforce the holes, simply drill a bigger hole and weld a tube into that such that the ID of the tube you weld in is the diameter of the pin you plan to use (well, slightly larger of course). I would assume this is probably mentioned in a Carol Smith book somewhere. </div></BLOCKQUOTE>

I think we missed that memo.

jd74914
01-12-2011, 06:43 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by murpia:
Now the chassis template rules exist, has that opened out the scope for drivers with different leg lengths to use pedals in the same location?

With more height in the leg zone, presumably knees can go up and down easier?

Regards, Ian </div></BLOCKQUOTE>

Our car works this way. It appears that we can comfortably accommodate about a 6in height differential just with varying knee position. That said, this might not be considered a great solution, but it does work for us.

moose
01-12-2011, 08:02 PM
Being on the comparatively short end of the spectrum, having space for taller drivers to bend their knees up works - but also think how far of a stretch it becomes for the shorter drivers.
If someone is working at full leg extension, its much much harder to act quickly and with full force, because the only motion is at the ankle, it takes the whole knee out of things. If you need to slam on the brakes for instance, you want to be able to put some pounds on there.
Now if your short folks are only running skid pad & accel.. go ahead and don't worry as much about how much they need to slam on the pedals.