Tilton FSAE Pedal Assembly

[Conor]

I thought I caught some posts about a special FSAE pedal assembly made by Tilton a while back. Does this exist or am I losing it? We ordered a wilwood reverse mounting assembly and it's pretty large. Anybody know where to find something smaller? We aren't able to make our own.

[Conor]

I thought I caught some posts about a special FSAE pedal assembly made by Tilton a while back. Does this exist or am I losing it? We ordered a wilwood reverse mounting assembly and it's pretty large. Anybody know where to find something smaller? We aren't able to make our own.

[Brian Evans]

Why aren't you able to make your own? Pedals are about as easy a thing to make as there is on a car. All you need are the raw materials, some hand tools, a way to weld, and a few hours of time.

Brian

[Conor]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Brian Evans:
Why aren't you able to make your own? Pedals are about as easy a thing to make as there is on a car. All you need are the raw materials, some hand tools, a way to weld, and a few hours of time.

Brian </div></BLOCKQUOTE>

Time. We don't have time to put something together that's atleast halfway decent and I'll be damned if I ruin the car by slapping some pieces of poorly cut metal on it.

[Adam L]

I'm in the proces of developing a set of pedals for a sports racer. It was designed around easy manufacturing (laser cuts and tube welds with only one part that needs to be fully machined) and to be a low mass assembly.

If you guys needs some help I would be glad to assist you in the development of your pedal assembly. My current development is about 20% done with a mass of 0.55lbs (should be around 3lbs fully assembled). There is still a lot of optimizing and details to be worked out, but I've spent maybe 2 hours and its 20% done, so that should put into perspective how quick it is to design an assembly.

Let me know if you have the parameters set (foot placement, spacing etc.)

http://www.adamlarnach.com/blogpics/main.php?g2_view=core.DownloadItem&g2_itemId=812&g2_serialNumber=1

[kapps]

Nice setup. It looks a lot like the brake/clutch setup in my old Lotus. It actually gives me an idea for my assembly next year.

[D Collins Jr]

Conor,
I'm confused. If you want a lighter pedal assembly, then build it. But you want to finish the car early, because of a lack of time. Yet, I've just read on another thread that your car will be running on the 15th of January. That sounds like plenty of time to build pedals. Perhaps even enough to screw up the pedal assembly and make it work.
Plus by making your own assembly, you can make the pedals to the specs that you want.

[Conor]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by D Collins Jr:
Conor,
I'm confused. If you want a lighter pedal assembly, then build it. But you want to finish the car early, because of a lack of time. Yet, I've just read on another thread that your car will be running on the 15th of January. That sounds like plenty of time to build pedals. Perhaps even enough to screw up the pedal assembly and make it work.
Plus by making your own assembly, you can make the pedals to the specs that you want. </div></BLOCKQUOTE>

I wouldn't consider it plenty of time, we're going to be stretched thin on that deadline. The solid modeling is also an issue because all of our senior talent is pressed to the limit with prints and model changes as is. I'm not trying to be a cop out about it, it's mostly a time constaint. We have the money to buy the assembly, but we don't the time to design it and machine it. Hence, I was looking for an easily purchased option. I appreciate the advice.

[Mike Hart]

Adam....interesting to see you design. I'd thought of something similar earlier in the year, but decided against it after a couple of our team members pointed out that the brake and accelerator being on the same pin could cause issues with the tech judges. They could argue that if the assembly got gunked up you could actuate the accelerator when pressing the brake.

Anyone got any novel ideas of mounting standard master cylinders by the way? I'd love to get a set of the direct mount ones that pivot with the pedal but they're like £200 a cylinder!

[Adam L]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Mike hart:
Adam....interesting to see you design. I'd thought of something similar earlier in the year, but decided against it after a couple of our team members pointed out that the brake and accelerator being on the same pin could cause issues with the tech judges. They could argue that if the assembly got gunked up you could actuate the accelerator when pressing the brake.
</div></BLOCKQUOTE>

The throttle, brake, and clutch pivot points (not modeled yet) have bearings pressed into them. If one of your bearings goes, you are up sh!t creek anyways. The throttle pedal will have an "un-stick" bar attached in case of a stuck throttle or similar issue as you describe.

Your team members bring up a great point though, it actually got me rethinking the design a bit. I actually borrowed the design from a late model Prost. I will look into fail safes though.

As far as your master cylinder issue, have you looked at Wilwood yet?

[Mike Sadie]

Wilwood does not have any cylinders like Mike mentioned. Here is one that AP offers:

http://apracing.com/car/cylinder/data.asp?code=CP5855
this cylinder was priced for us at $375 each.

These cylinders pivot at the pedal and in the very rear. The shaft is restrained co-axially with the cylinder body. They are pretty slick.

[Mike Hart]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Adam L:

The throttle, brake, and clutch pivot points (not modeled yet) have bearings pressed into them. If one of your bearings goes, you are up sh!t creek anyways. The throttle pedal will have an "un-stick" bar attached in case of a stuck throttle or similar issue as you describe.

Your team members bring up a great point though, it actually got me rethinking the design a bit. I actually borrowed the design from a late model Prost. I will look into fail safes though.

As far as your master cylinder issue, have you looked at Wilwood yet? </div></BLOCKQUOTE>

I had also looked into some form of lockout on the accelerator, but just gave in to making things a bit more traditional in the end for the sake of not spending too much time on it (we're a relatively small team and there are other areas that need more work!). I did actually come up with an even more extreme version of the above initially using a piece of bent tube for the accelerator with the brake pivoting about it! It would have needed some seriously good bearings and a lot of fail safes to get though tech, but would have certainly looked pretty insane :P Fair play for sticking to your guns though. Have you been looking through F1 Technical Analysis by Gorgio Piola by any chance? That's where I saw the design.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Mike Sadie:

Wilwood does not have any cylinders like Mike mentioned. Here is one that AP offers:

http://apracing.com/car/cylinder/data.asp?code=CP5855
this cylinder was priced for us at $375 each.

These cylinders pivot at the pedal and in the very rear. The shaft is restrained co-axially with the cylinder body. They are pretty slick. </div></BLOCKQUOTE>

Yup, those are the ones. Saw a couple of teams at FS Germany with them but was a little shocked when I got back and saw the price! Very neat little package but just not worth the money in my opinion. I don't really see how they can justify charging so much!

[Mike Sadie]

The AP MC's that are used most often are very basic and still cost $150-200. If you take a look at this tech. drawing, it shows the internal structure, which is significantly more complex than the cheaper one.

http://apracing.com/car/drawings/cp5854_1cd.pdf

you think thats crazy; AP's speed bleed fittings are $300 per wheel and their trunnion balance bar is 500.

[Dan Lentsch]

Conor,

I think i might know of something that will work for you.. We are planning on using it on our car this year due to similar constraints.
http://www.hyperracing.com/product.asp?prodid=34-599

hopefully you will find it somewhat useful

-Dan

[Steve Yao]

This is the Tilton alternative to the AP Racing rear-pivot unit:
Tilton 77 Series (http://www.tiltonracing.com/content.php?page=list2&id=25&m=b)

Retail cost is about the same ($365?), but tilton sells direct to SAE teams at wholesale cost if you give them a call. Keep in mind, rear-pivot MC's are designed to work best with a high-efficiency trunnion mount balance bar(Retail: ~$625 or some where there abouts.)
So you had better have a good reason for blowing 3x as much on your MC's and bar.

[Kyle Walther]

having a more consistent brake bias is a pretty good excuse.

i say this only because we spent the money and time buying those (77) MC's and designing our own trunnion Bias bar.

[Chris Allbee]

And to comment on that trunnion assembly...amazing.

The brake assembly is one of the things i feel most take for granted until you have the opportunity to drive a car with a really well thought out system. The feel and repeatability really gives you confidence under braking.

[Wesley]

Oh it's a dream compared to last years. Absolutely.

Pedals are one of the two most important driver interfaces. The other is the steering. Spend some time making them to the proper specs, your feet, your drivers, and your lap times will thank you.

How fast you go largely depends on how well your car feels. When you get the Quick-Kart with the floppy pedal and the off-kilter steering wheel are you going to be bitching about your driving or the kart sucking when you lose?

Same goes for FSAE. If you jank something together, expect jank for lap times, and jank for driver reaction.

(I'm boldly pioneering the word jank where it has never been before. Its suffix 'y' is taking a break.)

[Mike Hart]

One of our guys has actually come up with a pretty novel solution now so we don't have to use the super expensive master cylinders. Will have to post up some pictures when it gets made http://fsae.com/groupee_common/emoticons/icon_smile.gif