where can I get bump stops?

[LD]

I searched the forums and the web looking for bump stops but I came up with nothing. If any of you could give any recommendations as to a supplier I would appreciate it.

thanks,
Andrew
Rutgers Formula Racing

[LD]

I searched the forums and the web looking for bump stops but I came up with nothing. If any of you could give any recommendations as to a supplier I would appreciate it.

thanks,
Andrew
Rutgers Formula Racing

[jack]

http://www.prop-shop.com/g/s/sli2515.jpg

can be found at the:

http://www.rootsweb.com/~idpower/area_photos/Oliver_McKown_Hardware_store_in_American_Falls_ID_ 6_23_1908.JPG

[BryanH]

Koni sell very usable bump stops in at least 2 spring rates and they can give you rate curve for them.

[KU_Racing]

hint: you can buy solid rubber stock from almost anywhere, and it will 'machine' quite nicely

[F1engineer]

Koni Bump rubbers are made from BASF "elastogran". It is a small cell expanded polyurethane. You can buy it in bar form direct from BASF and machine it with a knife. They give instructions as to how to machine it.

By changing the shape of the bump rubber (cone angle length etc) you can tailor the load deflection curve to suit your precise requirements.

[LD]

thank you to all who contributed

[J.R.]

Hey,

Brining an old thread back, I can't find those Koni Rubbers. I can only find ones for 14mm dampers (shaft dia. I'm guessing) We're running Penske 7800's, (shaft dia ~=3/8 in, 9.5 mm) so they don't seem like they'll work. I don't really want to go with rubber washers, since I would like to already have a curve for me, rather than testing, since I am lazy and our completion deadline is closing in. Any help is awesome!

[exFSAE]

Why do you need them?

[J.R.]

To avoid bottoming the chasis while using springs soft enough for good mech. grip (2.5 ish Hz)

[rjwoods77]

J.R.,

Did you call the place we bought them from? They may have them.

[J.R.]

The only bump stops I have ever seen in our shop are on the Jupiter 6's from the '04 car. Those I have no idea where they came from. So I have no idea what you are talking about. In case you forgot, I come from engine team into a completely new suspension team within the past few months, so if they are around, I haven't seen 'em.

[rjwoods77]

Come on JR. We bought the dampers from someone(indy motorsports, one of our sponsors)and they have an invoice attached to them from last year which is in the cost report from last year. All the info you need is right in front of you. Get their number and ask if they have bump rubbers. Also did you look in the yellow penske box we have? Maybe there are some in there but I am pretty sure there wasnt.

[Mike Macie]

http://www.speedwaymotors.com/p/830,791_Bump-Rubber.html

http://hyperracing.com/product.asp?prodid=38-001

[Brian Evans]

Here are Penske bump stops.

http://www.pegasusautoracing.com/group.asp?GroupID=PENSKEPART

[Composites Guy]

Those penske bump stops are HUGE with a large diameter hole! I have a set untouched if you want 'em. I don't see them being practical for any FSAE project. Penske in Reading,PA (the manufacturer, not a reseller) says they don't currently have appropriate bump stops for the quarter midgets.

And... to the 'machining rubber' comment above, have you tried it??? Its not fun... some say 'freeze it in dry ice and machine it'... but that's not too fun either.

My suggestion is to buy soft round rubber tube (that looks like thick walled hose) with the ID and OD that you want from McMaster-Carr, and then razor blade it to length. I found some soft 'bouncy ball' consistancy elastomer on there that fits the Penske Quarter midget shocks' 3/8" diameter shaft quite nicely. Mcmaster Item # is 87235K111

[J.R.]

Mike,

The reason why 2 second internet searches don't work is b/c 2" OD bump stops don't fit our springs.

Composites Guy,

Thanks for the help! I think I'm gonna order some and hopefully get a force vs. deflection graph from our mat'ls lab. If your interested I can send it to you when it's done.

[Adambomb]

I remember when we got the last set of Risses we bought (in 2005), they literally had short sections of heater hose for bump stops. Then again that was the last year we ran them...