Tracy O'Brien brakes not braking

[JohnF]

I have TO brakes and matco master cylinders. After 637 hours, here is what I have learned about them: shortly after installing new pads, you will have to remove a spacer washer to keep the gap between the disc and pads correct. Otherwise you will have to pump them quite a bit to get full function. Also, they will get hot quick and take a while to cool off. If the gap between the pads and rotor is at the minimum, they will stick a bit when hot, and have diminished maximum braking power. They still work, just not as well as when cold. I have met several folks who have them, but didn't know how to adjust the gap. If you don't adjust the gap, you will get poor performance.

How do you adjust the gap? My installation just has 4 spacers and no obvious means of adjustment. Mine seem to have too much clearance, even with the new pads, and I wondered if that might be part of my problem. Since I did not build my airplane, I don't have the installation info for the TO brakes.

Thanks,
John

[DCASonex]

Sort of opposite situation here, have GP brakes with custom toe pedal operators in a TD. Very good control but have to really stand on them to hold for full power run-up. Suspect the major difference is the type of cylinder and the amount of mechanical advantage each linkage design provides.

David A.
*****************

I had no problem with holding power of the TO brakes with my Jab3300. I could do a full power run-up and it wouldn't move an inch... I was able to latch the brake handle on my flaps motor for a nice parking brake.

==
Michael

I also have TOB brakes. I switched from Great Plains disc brakes when I converted to a tail dragger. The GP brakes were so strong, I had to be careful not to lock up a tire on landing. I went with the TOBs because I also bought the TOB gear legs. They mate nicely. I also didn't like the squeaking I was getting from the GPs while taxiing.

The TOBs barely hold during runup at full throttle. They work fine during taxiing and light braking on landing and are smooth and quiet. I'd like more holding power, but they seem to be fine for me right now. The GPs sit in a box waiting for the coach to give them a second chance.

[fastj22]

I am one who didn't adjust the gap. I'll need to back and reread the instructions if I can find them.

[Bruce593SX]

Email Tracy off the email at the bottom of his web page, he responded to me on a Saturday within 2hours with the instructions attached

[JohnF]

Email Tracy off the email at the bottom of his web page, he responded to me on a Saturday within 2hours with the instructions attached

I'm already in contact with Tracy, but I appreciate the feedback from "the field". :)

John

[rbarber]

There are 3-4 washers under each the small tubes that the screws that hold the caliper together pass through.

[rbarber]

Oops! I really should not post from my cell phone...

OK, there are three main pieces of the wheel unit: the actuator, the rotor, or disc, and the outer plate. The outer plate is held in place with 3-4 BHCS screws. These screws pass through the plate, a tube, and the washers in question. The inside surface of the rotor rubs against these tubes. So the washers space the tubes out, moving the outer plate out. The more washers, the more brake pad space is available.

This is a bit awkward to do. A lot of parts to hold in place at once. I found it easier to wire tie the pads together to keep everything aligned, you may find an easier way.

Rob.

[JohnF]

Oops! I really should not post from my cell phone...

OK, there are three main pieces of the wheel unit: the actuator, the rotor, or disc, and the outer plate. The outer plate is held in place with 3-4 BHCS screws. These screws pass through the plate, a tube, and the washers in question. The inside surface of the rotor rubs against these tubes. So the washers space the tubes out, moving the outer plate out. The more washers, the more brake pad space is available.

This is a bit awkward to do. A lot of parts to hold in place at once. I found it easier to wire tie the pads together to keep everything aligned, you may find an easier way.

Rob.

Tracy has been very helpful and I've found out a couple of things. My brakes are an early version so they did not have the adjustment washers or the heat shield between the piston and the brake pad. I've got new parts coming to update to the latest configuration and do a complete rebuild. I'm hoping that a rebuild and thorough bleeding will make them behave better. I'll let you know how it goes.

John

[JohnF]

Well, the brakes are completely rebuilt and properly bled. And they actually work!

Thanks for all the help.

John

[wolfpack3]

I had no problem with holding power of the TO brakes with my Jab3300. I could do a full power run-up and it wouldn't move an inch... I was able to latch the brake handle on my flaps motor for a nice parking brake.

==
Michael

I also have TOB brakes. I switched from Great Plains disc brakes when I converted to a tail dragger. The GP brakes were so strong, I had to be careful not to lock up a tire on landing. I went with the TOBs because I also bought the TOB gear legs. They mate nicely. I also didn't like the squeaking I was getting from the GPs while taxiing.

The TOBs barely hold during runup at full throttle. They work fine during taxiing and light braking on landing and are smooth and quiet. I'd like more holding power, but they seem to be fine for me right now. The GPs sit in a box waiting for the coach to give them a second chance.

I'm in the process of converting to disc brakes on my Onex and have been wondering if there are any updates on brakes from Tracy Obrian or Great Plains. I will have to change the bolt pattern on the onex gear leg but that is a small price to pay for good brakes. The mechanical brakes aren't worth a darned even with the drum upgrade. I already have independent brakes with a full swivel tail wheel from Flyboy Accessories. Please advise if you prefer one brand over another and why.
I really don't like the idea behind the Aerobrakes because of the pressure put on the outer bearing.
Thanks in advance
Todd