MATCO BRAKE LINE SIZES QUESTION

[EDMO 1078]

Didnt want to have to scroll thru 2 or more pages of the stuff the came from the post about bearing and pad numbers to ask a simple question, and hopefully, get just a simple answer.

When you guys are talking about 1/8 inch brake line, I am supposing that you are talking about the ID of a .250 OD nylon line?

Do I understand this correctly?

Do I order 1/8 or 1/4 line from Spruce?

Really not wanting a debate about which line is better.

Also, if I use my gundrilled aluminum Grove landing gear, where the line attaches to the bottom of the leg, going up to the caliper, is this same line the one to use, or do I need Aerowhatever rubber lines?

ED in MO

[C5Engineer 1170]

Ed its labeled as 1/8" line. Matco sells it as well. I found it much easier to route and work with than the 1/4" line.

[FoxDB 17]

Didnt want to have to scroll thru 2 or more pages of the stuff the came from the post about bearing and pad numbers to ask a simple question, and hopefully, get just a simple answer.

When you guys are talking about 1/8 inch brake line, I am supposing that you are talking about the ID of a .250 OD nylon line?

Do I understand this correctly?

Do I order 1/8 or 1/4 line from Spruce?

Really not wanting a debate about which line is better.

Also, if I use my gundrilled aluminum Grove landing gear, where the line attaches to the bottom of the leg, going up to the caliper, is this same line the one to use, or do I need Aerowhatever rubber lines?

ED in MO

Ed,

I used the 3/16" O.D. tubing per this Link

http://www.aircraftspruce.com/catalog/appages/nyloseal.php

Dave

[saskavid 47]

Didnt want to have to scroll thru 2 or more pages of the stuff the came from the post about bearing and pad numbers to ask a simple question, and hopefully, get just a simple answer.

When you guys are talking about 1/8 inch brake line, I am supposing that you are talking about the ID of a .250 OD nylon line?

Do I understand this correctly?

Do I order 1/8 or 1/4 line from Spruce?

Really not wanting a debate about which line is better.

Also, if I use my gundrilled aluminum Grove landing gear, where the line attaches to the bottom of the leg, going up to the caliper, is this same line the one to use, or do I need Aerowhatever rubber lines?

ED in MO

Ed I would try to avid rubber lines at any point in the the installation if at all possible.You will always get some degree of ballooning effect then requiring more fluid and travel from the master cylinder leading to leverage decay and a reduction in available power.

[EDMO 1078]

Ed I would try to avid rubber lines at any point in the the installation if at all possible.You will always get some degree of ballooning effect then requiring more fluid and travel from the master cylinder leading to leverage decay and a reduction in available power.

Thanks for the info - Those Aeroquip lines are expensive. My only concern was that the nylon would be too stiff and interfere with the caliper actions. I know that ballooning causes losses of pressure.

ED in MO

[EDMO 1078]

Ed,

I used the 3/16" O.D. tubing per this Link

http://www.aircraftspruce.com/catalog/appages/nyloseal.php

Dave

Never thought about 3/16 - Guess it works OK or you would have changed it by now.

Thanks,

ED in MO

[FoxDB 17]

Never thought about 3/16 - Guess it works OK or you would have changed it by now.

Thanks,

ED in MO

The original builder used it in a thinner wall. I changed it to this when I installed my bush Gear.

[SuberAvid 617]

As Leni mentioned on the other discussion about brakes, line size would not affect brake presure unless there is significant fluid flow which is not the case with these brakes. Pressure is strictly a function of the force on the master piston and the piston area to get the pounds per square inch. If the lines are flexible (balloon) it will reduce this pressure, so the working presure of the lines is also important but it should not matter much between 1/8 or 1/4 except the 1/4 lines will require more volume to fill them due to the same amount of ballooning since there is more inner wall area.

[EDMO 1078]

As Leni mentioned on the other discussion about brakes, line size would not affect brake presure unless there is significant fluid flow which is not the case with these brakes. Pressure is strictly a function of the force on the master piston and the piston area to get the pounds per square inch. If the lines are flexible (balloon) it will reduce this pressure, so the working presure of the lines is also important but it should not matter much between 1/8 or 1/4 except the 1/4 lines will require more volume to fill them due to the same amount of ballooning since there is more inner wall area.

Shoot! And I thought that hydraulics and physics classes were over for me ! Now, you and Leni have me thinking again, and that can be dangerous for me !

I understand what you are saying about the pressure. Now I am thinking about volume in the little 1/2 inch bore MCs and transferring that volume to the caliper pistons. Appears that the flow thru 1/8 lines would be faster, requiring less pedal movement. Could I be right on this? Or does it matter not?

After 5 minutes of serious thought - the same volume from the MCs would be needed at the caliper no matter what size line, so speed of flow would not be the factor - just flow of volume. Got it ! Another 5 minutes, and I'll have another brainfart - Better stop while still sober ! Thanks.

ED in MO

Edited 5 Jul 2012 by Ed In Missouri

[Av8r3400 1179]

Now you're getting it. It wouldn't matter if you were using a 12" diameter sewer pipe, the volume of flow from the M/C is the same. How far that volume of fluid flows in the tubing means virtually nothing as long as it can flow with minimal restriction.

[saskavid 47]

I used that crummy/clumsy to workwith 1/4 in parker parflex with a working pressure rating of 450psi to do the pressure testing of the setup I made.Holding 600 plus psi I took measurements with a digital caliper trying to detect any swelling.Near as I could tell there wasn't any.As a function of percentage I'm pondering that any of these lines can't be any more than a few points appart.Of course a distortion could be happening internally that doesn't make it measurably thru to the outer wall.

[EDMO 1078]

I used that crummy/clumsy to workwith 1/4 in parker parflex with a working pressure rating of 450psi to do the pressure testing of the setup I made.Holding 600 plus psi I took measurements with a digital caliper trying to detect any swelling.Near as I could tell there wasn't any.As a function of percentage I'm pondering that any of these lines can't be any more than a few points appart.Of course a distortion could be happening internally that doesn't make it measurably thru to the outer wall.

I'm sure that if the outrer wall did not expand, there was not enough change inside to worry about.

Spruce lists NNR at 1500, NBR at 2000, and some other "super slick" nylon at 2500 psi.

I have a tendency to "build heavy & worry less. Guess I will go with the heavier of these.

Thasnks,

Ed in MO