Brake line fittings?

[sekps]

I'm installing the Grove disc brake conversion on my experimental L-18C and I decided to run a flexible hose (instead of the supplied copper tube) from the original brake line to the floating brake caliper.

According to the PA-18 drawings the original brake line fittings are "105 x 4". Which thread size is this? Is it an SAE standard designation, or what?

The Swedish suppliers aren't really familiar with a "105 x 4" fitting so I thought maybe the thread size and standard might help...

/Mattias

 

[Dano Bardwell]

brake lines

I'm not shore how things work out on your side of the planet but if you can get to a real hose shop, braided stainless lines are what we use around here & the P/N for standard gear is 124001-4cr-0390 & for 3" extended gear P/N 124001-4cr-0420 the fittings on the calipers will be either a 90 degree P/N an 822-4d or a 45 degree P/n an 823-4d im not shore what you have up top but a an 816-4d might get you in the ball park hope that helps

 

[bob turner]

No, wait: The original Cubs were supplied with automotive brake parts, and that carried over to Super Cubs until the factory got Clevelands on the type certificate. The Grove brake is certified with Weatherhead fittings, and that strange # I believe is a Weatherhead part #. I can check, and get back if you don't get it straightened out. I am using the Grove copper lines as specified in the type certificate, and have had not one speck of a problem in over 500 landings! The brakes as supplied are simply spectacular!

 

[Steve Pierce]

Mattias, We get them at the local auto parts store. AN fittings will probably fit your flex hose easier. I can get the weatherhead "105 x 4" fitting at NAPA and ship them to you if you decide to go that route.

 

[Dano Bardwell]

brake lines

sorry Mattias, I wasn't thinking auto parts store I was thinking aircraft parts after all its just your cub. & piper did use that stuff at one time. its att good.

 

[Steve Pierce]

Aircraft Spruce has the weatherhead fittings.

 

[CptKelly]

Grove Brakes....

Since they were mentioned, I also have to agree, the Grove brand brakes work really well, and will hold my 185hp XP-360 on a Smith Kit at full throttle. Great brakes, and no problems with them.

Mike

 

[sekps]

Thanks!

All the fittings were included in the kit (actually everything was included, like an extra long drill bit to drill the discs) so that's no problem. But I thought that it would be better to have a flexible hose to the floating caliper than a (relatively) stiff tube.

I spent the afternoon looking for car brake hoses that might fit, but I guess it wasn't more than a good try. I also talked to a company nearby and they could manufacture the hoses with the right fittings. They just wanted $80 - per hose! If I bought 100 or more I'd just have to pay $15 per hose...

So I'll use the included copper tubes. I guess there's a good reason why they are included - and it's probably because they work fine...

/Mattias

 

[Dave Calkins]

Bringing up the topic of stainless steel braided line....

I used to think that stuff was the greatest for nice brake line. My thoughts have changed.

If the stuff touches your gear leg, it will rub off paint. Also, if the line is captured at the gear leg front tube by a short sectionf of tubing instead of the original Piper crimp method, the lines must be built in place and are then not removable easily. Also, the inside of the little holder tube will end up with no paint on the inside and then rust.

These are my observations, so I'm looking for an alternative.

DAVE

 

[Crash]

Use Aeroquip 303-4 hose or Strato Flex 111-4. The Aeroquip fittings are 491-4. Strato Flex fittings are 300-4S. I've tried the Stainless braided hoses too and was not impressed with the amount of crimp the fittings put on the hose. Crash

http://www.aircraftspruce.com/menus/ap/hose.html

http://www.aircraftspruce.com/menus/ap/hosefittings.html

 

[behindpropellers]

Crash-

Didn't you put some bulkhead fittings through the bottom of your belly for the brake lines? Have any pics?

Tim

 

[bob turner]

I have had absolutely no problems with the Grove copper line from gear leg to caliper. There is plenty of flexibility in the system. Original Cubs simply had a cutout in the inspection plate below the master cylinder, in which a grommet fit. I use a rectangular aluminum plate, screwed to the fabric with #4s - the same grommet goes there. The hose out of the Scott is a 1/8"NPT and an auto fitting. Probably something off the same car that provided the trim handle.

 

[sekps]

By the way, is it 37° or 45° flange angle for the Weatherhead fittings?

/Mattias