Brakes - activation?
11-21-2007, 07:00 PM
#1
Thread Starter
Join Date: Jul 2005
Location: Bairnsdale, AUSTRALIA
Posts: 870
Likes: 0
Received 0 Likes
on
0 Posts
Brakes - activation?
Just a real simple question - figured you jey guys could answer it. I'm considering putting brakes on the main wheels of a B25 Mitchell twin (no, not turbines sorry 
),20 lbs, Robarts probably, but realised I'm totally ignorant of their operation.
Do you have them on a separate channel on the Tx? Are they proportional? I'm guessing one of the sliders on the back of my JR PCM9x (9### in the U.S.?) Tx would be convenient, and I'll have a spare channel in the Rx if needed.
Thanks for any tips,
Cam
p.s. Main reason for wanting brakes was to run-up the engines before take-off, plus our strip is short so they may be handy after landing too.
),20 lbs, Robarts probably, but realised I'm totally ignorant of their operation.Do you have them on a separate channel on the Tx? Are they proportional? I'm guessing one of the sliders on the back of my JR PCM9x (9### in the U.S.?) Tx would be convenient, and I'll have a spare channel in the Rx if needed.
Thanks for any tips,
Cam
p.s. Main reason for wanting brakes was to run-up the engines before take-off, plus our strip is short so they may be handy after landing too.
11-21-2007, 07:04 PM
#2
My Feedback: (28)
Join Date: Apr 2003
Location: Heath,
TX
Posts: 3,886
Likes: 0
Received 0 Likes
on
0 Posts
RE: Brakes - activation?
Yes, run your brakes on a slider, makes life easy.
Some people also mix them with down elevator.
The brakes will be proportional if you have a proportional valve like a UP-6 or a Smooth Stop
Some people also mix them with down elevator.
The brakes will be proportional if you have a proportional valve like a UP-6 or a Smooth Stop
11-21-2007, 07:08 PM
#4
My Feedback: (8)
Join Date: Mar 2002
Location: Helena,
AL
Posts: 516
Likes: 0
Received 0 Likes
on
0 Posts
RE: Brakes - activation?
I use a bvm smooth stop, for braking, that is mixed with down elevator. The gear switch turns on the braking mix when placed in the down position.
Jed
Jed
11-21-2007, 07:31 PM
#6
RE: Brakes - activation?
ORIGINAL: FL510
Man, I need to work on my Typing speed.
Man, I need to work on my Typing speed.
One question about this topic...... What is most prefered? Electronic (Ultra P) or manual (BVM Smooth Stop) ?
Mike
11-21-2007, 07:51 PM
#7
My Feedback: (4)
Join Date: Dec 2001
Location: Longwood ,
FL
Posts: 2,341
Likes: 0
Received 0 Likes
on
0 Posts
RE: Brakes - activation?
Also,
If your retracts are pnuematic, use a seperate air tank and filler for the brake system. It's best to keep gear and brake systems seperate for obvious reasons.
Harley Condra
BVM REP
JetCat REP
If your retracts are pnuematic, use a seperate air tank and filler for the brake system. It's best to keep gear and brake systems seperate for obvious reasons.
Harley Condra
BVM REP
JetCat REP
11-22-2007, 06:50 AM
#10
Senior Member
Join Date: Sep 2005
Location: SaleVic, AUSTRALIA
Posts: 124
Likes: 0
Received 0 Likes
on
0 Posts
RE: Brakes - activation?
Camdyson, if you get a chance, take the short drive to the Sale Model Club. There are a few guys there with jets, all with brakes. I'm sure they'll be happy to share their experiences.
Not this weekend though, I think the jet guys wil be at Jets Over Wangaratta.
Cheers,
Greg
Not this weekend though, I think the jet guys wil be at Jets Over Wangaratta.
Cheers,
Greg
11-22-2007, 08:49 AM
#11
Senior Member
Join Date: May 2006
Location: Rome, ITALY
Posts: 165
Likes: 0
Received 0 Likes
on
0 Posts
RE: Brakes - activation?
ORIGINAL: FILE IFR
One question about this topic...... What is most prefered? Electronic (Ultra P) or manual (BVM Smooth Stop) ?
Mike
One question about this topic...... What is most prefered? Electronic (Ultra P) or manual (BVM Smooth Stop) ?
Mike
I think you meant the Jet-tronic valve that is electronic.
I have a UP6 and it works just great.
Ciao!
Mauri
11-22-2007, 12:39 PM
#13
RE: Brakes - activation?
TRIM AIRCRAFT BRAKE VALVE.........Available from Great Northern Models here in the Western Hemisphere....Most likely direct in Australia....Hands down the best kept secret in turbine modeling.
If you have a JR 10X, set it up EXACTLY like the instructions say. For your JR 9303 or if you have a FUTABA, send me a PM and I will tell you about the set-up. Guys, this valve is completely proportional, light weight and DOES NOT LEAK. My A-7 has held air for WEEKS...during the hot summer when I shut down flight operations with no leaks.........I have never seen a smooth stop that didn't leak at some point. I have brakes mixed with down elevator and on a slider. A unique feature to the Trim valve is that you can set a partial "parking brake" by holding a bit of down elevator for a couple seconds. This can be released immediately with a touch of up elevator. On landing, I just pulse in a little down elevator after touchdown and the brakes have just enough drag to slow the airplane. Then more brake can applied with more down elevator. For full braking, use the slider.
In the photo, the valve is a the top of the page just under the plywood servo tray.
Tailwinds,
John
If you have a JR 10X, set it up EXACTLY like the instructions say. For your JR 9303 or if you have a FUTABA, send me a PM and I will tell you about the set-up. Guys, this valve is completely proportional, light weight and DOES NOT LEAK. My A-7 has held air for WEEKS...during the hot summer when I shut down flight operations with no leaks.........I have never seen a smooth stop that didn't leak at some point. I have brakes mixed with down elevator and on a slider. A unique feature to the Trim valve is that you can set a partial "parking brake" by holding a bit of down elevator for a couple seconds. This can be released immediately with a touch of up elevator. On landing, I just pulse in a little down elevator after touchdown and the brakes have just enough drag to slow the airplane. Then more brake can applied with more down elevator. For full braking, use the slider.
In the photo, the valve is a the top of the page just under the plywood servo tray.
Tailwinds,
John
11-22-2007, 01:15 PM
#14
My Feedback: (4)
Join Date: Dec 2001
Location: Longwood ,
FL
Posts: 2,341
Likes: 0
Received 0 Likes
on
0 Posts
RE: Brakes - activation?
John,
I am sure that there are numerous BVM "Smooth Stop" brake valves that don't leak air over an extended period.....I have one installed that has held air for over five months, and so far, it has lost NO pressure. I always keep my fingers crossed, cause ya never know......Murphy's Law generally prevails.
Setup ideas....
If you mix the brakes with down elevator, you will loose brake pressure every time you apply down elevator during flight, unless the mixer is activated by the landing gear switch when moved to the"down" position. Then it will only loose (use) air pressure after you extend the gear and use some down elevator.........after the gear is down in the landing pattern a small pressure loss should not be a problem.
This is easy to setup on a JR10X.
The electronic valves are preferred by many fliers but IMHO, there is no valve that will satisfy everyone. As I understand them, the electronic valves do not have parking brake capability, as they vent pressure to the atmoshphere when the radio is shut down. The tank shouldn't loose pressure, but there is no longer any output from the valve to the brakes until the radio is turned back on and the valve resets itself.
A servo operated mechanical valve will still hold pressure as long as it's servo remains in the "brakes on" position, regardless of the radio "ON or OFF" status allowing the brakes to function as parking brakes.
Take a good look at what's available in the marketplace and what the fliers in your area are using, and what you have read on RCU before making your decision.
Good luck to ya............
Harley Condra
BVM REP
JetCat REP
I am sure that there are numerous BVM "Smooth Stop" brake valves that don't leak air over an extended period.....I have one installed that has held air for over five months, and so far, it has lost NO pressure. I always keep my fingers crossed, cause ya never know......Murphy's Law generally prevails.
Setup ideas....
If you mix the brakes with down elevator, you will loose brake pressure every time you apply down elevator during flight, unless the mixer is activated by the landing gear switch when moved to the"down" position. Then it will only loose (use) air pressure after you extend the gear and use some down elevator.........after the gear is down in the landing pattern a small pressure loss should not be a problem.
This is easy to setup on a JR10X.
The electronic valves are preferred by many fliers but IMHO, there is no valve that will satisfy everyone. As I understand them, the electronic valves do not have parking brake capability, as they vent pressure to the atmoshphere when the radio is shut down. The tank shouldn't loose pressure, but there is no longer any output from the valve to the brakes until the radio is turned back on and the valve resets itself.
A servo operated mechanical valve will still hold pressure as long as it's servo remains in the "brakes on" position, regardless of the radio "ON or OFF" status allowing the brakes to function as parking brakes.
Take a good look at what's available in the marketplace and what the fliers in your area are using, and what you have read on RCU before making your decision.
Good luck to ya............
Harley Condra
BVM REP
JetCat REP
11-22-2007, 01:43 PM
#15
RE: Brakes - activation?
Harley,
I'm glad that you have success with the Smooth Stop. The Trim instructions detail just what you said. The mix is activated by the retract switch. I prefer to run separate air systems for gear and brakes. On my A-7, I have the brakes and door cylinders on one system and the gear on the other. The thought being that those little cylinders are prone to leaking............I'd rather have gear and no brakes rather than the opposite! On of my buddies runs a single air system but he taps the brake supply off of the down line on the gear. The brake servo works the whole flight but the valve only gets air with the gear down.....................
Tailwinds,
John
I'm glad that you have success with the Smooth Stop. The Trim instructions detail just what you said. The mix is activated by the retract switch. I prefer to run separate air systems for gear and brakes. On my A-7, I have the brakes and door cylinders on one system and the gear on the other. The thought being that those little cylinders are prone to leaking............I'd rather have gear and no brakes rather than the opposite! On of my buddies runs a single air system but he taps the brake supply off of the down line on the gear. The brake servo works the whole flight but the valve only gets air with the gear down.....................
Tailwinds,
John
11-22-2007, 02:33 PM
#16
My Feedback: (4)
Join Date: Dec 2001
Location: Longwood ,
FL
Posts: 2,341
Likes: 0
Received 0 Likes
on
0 Posts
RE: Brakes - activation?
John,
Just a few thoughts.................
I don't feel that those small cylinders are prone to leaking......a small amount of lubrication occasionally injected into the air line that supplies the cylinders will extend the life of the o-rings and serve to prevent leakage or failure.
Way back in the days when the "Rhom Air" gears were new technology, we used Freon to power the gear instead of air....Rhom even provided and sold an adapter to tap the Freon cans for fill-up. One of these adapters was part of the landing gear system. We were instructed in the installlation manual to inject a small amount of refrigeration oil into the filler valve occasionally to make sure that the o-rings were lubricated because the Freon washed the lube from the o-rings and cylinder walls.
Even though we now use air pressure instead of Freon, we still need to lubricate the system o-rings occasionally to maintain good service. To extend the lifespan of your o-rings, you can use P/N BVM1945 Thin Lube" injected into the system filler valve. The air carries the lubricant down the lines to the o-rings.
It is amazing, just how much better o-rings survive when they are properly lubricated. I'm not pointing the finger at you or anyone else in particular, but many flyers don't know or remember that fact, and wonder why they sometimes have a cylinder failure (leak or otherwise)....dried out o-rings don't seal properly.....both extension/retaction and door cylinders require periodic maintenance.
BVM also offers a good assembly lube to use when replacing o-rings. Use "Parker Super O-Lube" P/N BVM5779.
Harley Condra
BVM REP
JetCat REP
Just a few thoughts.................
I don't feel that those small cylinders are prone to leaking......a small amount of lubrication occasionally injected into the air line that supplies the cylinders will extend the life of the o-rings and serve to prevent leakage or failure.
Way back in the days when the "Rhom Air" gears were new technology, we used Freon to power the gear instead of air....Rhom even provided and sold an adapter to tap the Freon cans for fill-up. One of these adapters was part of the landing gear system. We were instructed in the installlation manual to inject a small amount of refrigeration oil into the filler valve occasionally to make sure that the o-rings were lubricated because the Freon washed the lube from the o-rings and cylinder walls.
Even though we now use air pressure instead of Freon, we still need to lubricate the system o-rings occasionally to maintain good service. To extend the lifespan of your o-rings, you can use P/N BVM1945 Thin Lube" injected into the system filler valve. The air carries the lubricant down the lines to the o-rings.
It is amazing, just how much better o-rings survive when they are properly lubricated. I'm not pointing the finger at you or anyone else in particular, but many flyers don't know or remember that fact, and wonder why they sometimes have a cylinder failure (leak or otherwise)....dried out o-rings don't seal properly.....both extension/retaction and door cylinders require periodic maintenance.
BVM also offers a good assembly lube to use when replacing o-rings. Use "Parker Super O-Lube" P/N BVM5779.
Harley Condra
BVM REP
JetCat REP
11-26-2007, 07:24 AM
#18
Thread Starter
Join Date: Jul 2005
Location: Bairnsdale, AUSTRALIA
Posts: 870
Likes: 0
Received 0 Likes
on
0 Posts
RE: Brakes - activation?
Holy cow - nothing's ever straightforward in this hobby is it! (Well, not when you jet jocks get hold of it....)
Seriously, I appreciate all the advice. By chance, there will be a dedicated spot for a spare air tank in the new plane, so it would only be decent to use it
. Retracts will be running off a separate tank located elsewhere.
Mixing to down elevator only when "gear down" is selected makes sense, with the slider as a full brake. "Hand brake" setting with a long input sounds waaay too clever - may have to get a 10-year-old to program this plane for me[sm=lol.gif]
Again, thanks for the input everyone,
Cam
p.s. Found my first Tx in the workshop the other day, circa 1980 - a JR Circus 2 ch. AM, dry cells, no reversing.........
Seriously, I appreciate all the advice. By chance, there will be a dedicated spot for a spare air tank in the new plane, so it would only be decent to use it
. Retracts will be running off a separate tank located elsewhere. Mixing to down elevator only when "gear down" is selected makes sense, with the slider as a full brake. "Hand brake" setting with a long input sounds waaay too clever - may have to get a 10-year-old to program this plane for me[sm=lol.gif]
Again, thanks for the input everyone,
Cam
p.s. Found my first Tx in the workshop the other day, circa 1980 - a JR Circus 2 ch. AM, dry cells, no reversing.........
