On Apr 12, 8:30 pm, Eric Greenwell wrote:
sisu1a wrote:

I was hoping someone with surge and electric brake experience would
comment. Since that didn't happen, I'll comment so Paul won't feel ignored.

Electric brakes are actually more reliable, require less maintenance,
are much more flexible, and bottom line just plain all around work
better for glider trailers and this is why:
2. They are easier to properly maintain- no bleeding/topping off/
corrosive fluids

Fluids? The most common factory trailer (Cobra) is all mechanical.

Fair enough, no fluid. Electrics are still more flexible as well as
more reliable. Why more reliable, well I know for sure that my
electric brakes work. How do I know? I can test them, for ALL
functions and responsiveness, throughout their entire performance
range. As far as I know the only tests for surges are 1. put on the e-
brake, does it roll? 2. Get trailer/tow vehicle up to speed. Give a
firm application to the brakes. Did you feel the trailer first push
into the vehicle before pulling on the hitch? (that's got to be good
for the car) I suppose thats all there is you can test them for, since
they are a binary system. on or off.


3. Brakes on trailer can be applied independently of brakes on the
car, in addition to working in unison with the car's brakes, It is
just plain nice to have the option of tapping just the trailer's
brakes when a semi with a 20mph differential speed sets you trailer
wagging :-)

If the wagging is a safety concern, I suggest the "fix" is driving
slower until you can modify your equipment to handle upsets without your
intervention. If not, there will be a day when tapping the trailer's
brakes don't work because it's a 30 mph differential, or a strong
thermal, or cross wind catches you coming out from behind a cut in the
road way, or you are distracted and slow on the tapping, or two things
catch you at the same time, or ...

Wagging is not one of the concerns I put the electric brakes on to
fix, that was an unintended benefit that it conveniently helps with
(the 7 point buck staring at me in the middle of my lane while driving
around a 55mph blind corner on a mountain highway in Wyoming was my
actual inspiration). It is especially nice though, when I am teaching
someone else to drive my trailer. For me, I have found that correctly
steering with the pressure change of the 'bow wake' of trucks etc,
(using resistance to damp out the movement before it even sets up an
oscillation) to be much more effective, but I can't seem to teach this
technique to anyone else, so I like that they can 'tap' the brakes
until they figure out the finer finesse of sailplane trailering (if
they ever figure it out). Electric brakes ALSO work automatically too
of course, according to the level you set them to (which to reiterate
can be easily adjusted WHILE driving). The manual override is what you
would "tap" (actually it is a throttle lever, and again you have a
voltage readout so you can tell, besides feel alone, how much braking
you are giving it). If one was too unaware to use normal braking, then
perhaps they should not be driving at all. I am focusing on hardware,
because it is easier to share the findings. I fail to see how a
thermal will affect me while driving, and your other points actually
support the case for electrics, since they not only automatically work
but can be tuned to current needs, as well as to be used manually.

-WARNING-more personal opinion coming-For that matter, I
highly recommend against using engine braking on any vehicle under
12,000lbs that has hydraulic brakes on it, in all but extreme
downgrades (over 7%, longer than 5 miles). Brake pads cost $20-$40,
resurfacing drums/rotors adds another $45-$180. A transmission costs
more like $4,000 (installed) and the more yet for a motor. Clutches
are not cheap either for that matter.

Why do you think engine braking is hard on the engine and transmission?
At least, for automatic transmissions, where you keep it in 3rd instead
of letting it slip into OD/4th gear? None of my vehicles over the last
16 years have cautioned against that. Manual transmissions -- maybe good
advice, if the driver isn't well trained in them.

Because you are putting load on it, load that is frankly quite
avoidable. Load = wear, period. I choose to put the load/wear my
brakes as opposed to major drive train components. The loading of most
braking is WELL within the safe tolerances of these systems. I do not
do this at the expense of safety, nor do I suggest anyone else to.
Drive however makes you comfortable and keeps you in 'the zone'
please, as I have to share the road with you and I don't want anyone
feeling out of their element. I do recommend that people experiment a
little with their vehicles and driving styles from time to time with
regards to braking and gearing. It is a good thing to to do as an
academic exercise if nothing else, as there are always things that can
be learned (again, safety first!). Naturally the car manufacture is
NOT going to caution you against ruining expensive parts they are more
than happy to sell you.


4. Electric brakes work as they are supposed to while reversing,
meaning they only engage when the car's brakes are applied, as opposed
to engaging during changes in acceleration (again, at least with a
good controller like ones mentioned).

Huh? My surge brakes disengage while I'm backing up, which is how they
are supposed to work. I don't need brakes at 5 mph.


I'm glad that Cobra actually provides some decent hardware on their
$20,000 trailers. I feel safe to say that most of the surges out there
do NOT have the free-backing mechanism or a reverse solenoid hooked
into the tow vehicles wiring. While I agree that you may not need
brakes at 5mph, I can imagine cases where they might be nice to have,
albeit rare.

You will really notice a
difference the first time you have to really do some serious backing
up.

What difference would I notice?

Well YOU would not notice much seeing as you have the disengage
mechanism, but most folks with classic substandard surge getups sure
would!

They never accidentally engage, like surges very commonly do while
driving down hills/grades.

You mean, while backing down a hill? My surge brakes would never do that
for two reasons: 1) I'm backing up, so they are disengaged 2) the tow
vehicle is not pushing on the tongue, so the brakes can't even be activated.

No, I do not mean while backing down a hill. I mean when your trailer
is trying to overrun the tow vehicle while you are driving down a
steep enough hill and you had no idea your brakes were engaged for an
entire down grade-until you got to the bottom and smelled it-or a
wheel fell off etc. It was this very phenomenon that initiated my
original post on the subject some time back.

5. You keep a breakaway backup battery system in the trailer so the
brakes automatically engage in the unlikely event of a total
separation, stopping the trailers movement and holding it there (20
minutes at max hold is usually the typical minimum requirement for the
breakaway kit's internal battery). Good breakaway kits have a built in
'smart' charger and a charge indicator test light, and charge
automatically while engaged to the tow vehicle. This built in charger
can be tied into your ship's battery so it will also charge it (only
while driving, unless you hook up a solar panel to the line in on the
charger unit, but that's another post...)

Tell me again why it's an advantage to keep a battery and charger in the
trailer, instead of none at all, like my surge brake system.


Because then you have a battery/charger in your vehicle. It is nice to
have emergency 12v power when and if it were needed. A lot of things
could be powered off that battery in a pinch. Best of all, you can
splice into the charging circuit and use it to keep your plane's
batteries topped off if you hook solar panels up to it. Hmmm, now that
I think back, weren't YOU looking for a solution to keep your solar
panels from frying batteries a little while back?

10.Your 'buddies' can't do you the kind favor of accidentally leaving
your E-brake on when they come to get you!

I know I'd REALLY miss the parking brake on my 2400 pound trailer, but I
could get along without it on a 1600 pound trailer.

With electric brakes you have a battery/charger in the trailer (sound
familiar?). This is intended as an emergency breakaway backup and has
a pull switch on the tongue. Although it is not intended as an e-
brake, that is essentially what it is. If you ever needed to use the e-
brake to man-handle the trailer, it is actually quite easy, but the
manufacture does recommend against using it in perilous situations.
There is also the drawback that you have limited time with this action
(Federal minimum for battery is 15 minutes of full locked brakes), but
that seems like it should do just fine for any grunt work you may need
to accomplish, particularly if you have chocks too.

As a follow up to this "article", I don't think perfectly good surges

should be thrown to the curb. I just don't think much effort should be
made to fix them once you finally realize they are NOT actually
working as they should be (hopefully not due to an unpleasant event).

My Cobra trailer has 130,000+ miles on it, and so far the only real
braking system fix was replacing a drum, and one complete set of brake
shoes. I do put a grease gun to the sliding components on the tongue
every year, and perhaps the frequent use my trailer gets prevents some
problems.

That is undeniably a lot of miles. Your opinion is indeed valid for
your trailer, and your logic can not be argued with as it applies to
your case. Brake shoes are expected to wear, and replacing a single
drum is not a big deal. Greasing the sliding components is a very good
practice, that is followed by everyone would probably spare a lot of
heartache in the end. I think you hit the nail on the head about your
frequent use theory as well. I also suspect that Cobra may actually
use decent parts, which is commendable. Clearly this is not the case
with ALL trailer manufacturers however, and THIS is where the electric
conversion really should come into play. It should be noted though,
that although Cobra's surge system has good maintenance reliability
(recent crops anyhow), that does not circumvent the fact that electric
brakes can outperform surges-as far as the action of braking is
concerned- in both stopping power and most certainly in finesse. There
is a reason electrics are the most common type of brakes in horse
trailers; they can be used smoothly but firmly if needed, but with an
amazing degree of control and usable adjustment range.

While I'm not persuaded I'd be better off with electric brakes, I still
think Paul makes a strong case for them, and they certainly seem worth
considering.

To reiterate, I'm not trying to persuade anyone with a functional
getup -that they are happy with- to become a 'convert'. But do be open
to other options when and if the time comes where you find yourself
considering paying $300 or more to fix broken surges. At that price
level, you are getting close to having a complete electric setup, and
may be happier with the electrics. Now I'm sure someone else will
just pull the pin out and throw it back again, sigh...

No longer feeling ignored,
Paul Hanson

--
Eric Greenwell - Washington State, USA
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