Electric Brakes On Komet Trailer

On Tuesday, February 19, 2019 at 5:58:47 AM UTC-8, wrote:
Drilling through the inner sliding tube is a pretty bad idea IMHO because it weakens the tube and adds an unwanted stress riser. A better solution is to make a two-piece collar that can clamp over the tube between the tongue housing and the hitch, thus preventing it from compressing.

Yes.
Besides the odd idea of disabling the trailer brakes, drilling holes in the tongue to promote tongue failures we've previously witnessed seems misguided.
It seems to me that failure mostly occurs with a heavily-sprung tow vehicle, long cantilever behind the rear axle, or an overweight trailer tongue. Combinations of those are a gamble.
The max weight rating is on the tongue, most are 100kg.

OP:
One thing I imagine electric brakes would be useful for would be engaging them independently of tow car brakes if there is instability.

Personally find AlKo trailer brakes pretty easy to maintain.
Perhaps change the tongue compression damper more often? If you live where things get rusty, routinely treat the Bowden cables with LPS-3. Grease fittings are there to be used.
Download the trailer manual (Spindelberger have it available, perhaps Anschau)
Jim

Besides the odd idea of disabling the trailer brakes, drilling holes in the tongue to promote tongue failures we've previously witnessed seems misguided.
It seems to me that failure mostly occurs with a heavily-sprung tow vehicle, long cantilever behind the rear axle, or an overweight trailer tongue. Combinations of those are a gamble.

I agree most of the failures I've heard about involve motorhomes. I check for cracks frequently anyway where the tongue enters the trailer (the big stress point), and remove the dolly wheel each time so it doesn't ground.

The hole in the inner tongue shouldn't have any effect unless bending stress is being transferred from inner to outer tube via the slot in the inner tube and the thru bolt/damper mounting. Another hole in the outer tongue could, but there's already a hole there for the rear damping strut mount as well as fittings welded to it (which are stress risers).

As for whether you would WANT to disable the braking system, I don't know. I've done it twice to get to/from contests where there were other brake problems. I don't intend to otherwise but it would be nice to be able to in a hurry if I had to.

One thing I imagine electric brakes would be useful for would be engaging them independently of tow car brakes if there is instability.

Yes, I've never used electric brakes but that capability sounds very nice (and have heard it is from others).

Personally find AlKo trailer brakes pretty easy to maintain.
Perhaps change the tongue compression damper more often?
Keep in mind that this trailer is 27 years ago. My previous Komet was 13 years old when I sold it and had few problems. Such is progress.

I changed the damper strut this summer. Not much different in force or damping than the one I removed.

If you live where things get rusty, routinely treat the Bowden cables with LPS-3. Grease fittings are there to be used.

I grease the fittings in the tongue every year, but those are for the bushings in the outer tongue tube. The cables are more difficult to treat but I plan to do it this spring. Must remove the parking brake cables from the central actuator rod and the backing plates, then spin the cables while pouring/squirting lube into the them.

Download the trailer manual (Spindelberger have it available, perhaps Anschau)

I'm from the old school. I have the paper manual that came with the trailer!

I would love, love, LOVE to hear what I could do to make this system reliable. But each time I've asked for input about a problem, I've gotten different answers. I agree when it's working properly, it's great. Keeping it working properly has been my challenge.

Chip Bearden

wrote on 2/18/2019 9:58 PM:
I don't think disabling trailer brakes is a good idea. There is stability under heavy braking to consider not just retardation. I have twice, separated by about 25 years, had the situation of having to emergency brake on a motorway, the trailer start to swing out (not just sway) and then snap straight as the trailer brake bit fully. My impression was that if the trailer had been unbraked one or both times it would have jackknifed and possibly caused a multiple vehicle incident. Thankfully I will never know for sure but I would never tow a glider trailer any distance without good brakes.

With a 11,500 tow vehicle and 2500lb trailers, brakes are almost irrelevant for
stopping the combination - I did the experiment on an out and return to Alaska.
And now, the tow vehicle is 13,500lbs - it's even steadier.

Stability is not an issue with the huge difference in weight and the long wheel
base (with four tires on the rear) of the motorhome. Also, I tow 60 mph, pass at
70, and "flutter speed" is well over 100 mph. The trailer has so little affect on
the motorhome, I can't feel what it's doing, not even if a tire blows (done that
experiment).

The best argument for brakes in my situation is dampening the swaying if the
trailer came off the ball, but I believe the chains are strong enough to withstand
the whipping that would ensue, and the motorhome is heavy enough to be easily
controlled during the stop.


--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

On Tuesday, February 19, 2019 at 7:02:43 PM UTC, Eric Greenwell wrote:
wrote on 2/18/2019 9:58 PM:
I don't think disabling trailer brakes is a good idea. There is stability under heavy braking to consider not just retardation. I have twice, separated by about 25 years, had the situation of having to emergency brake on a motorway, the trailer start to swing out (not just sway) and then snap straight as the trailer brake bit fully. My impression was that if the trailer had been unbraked one or both times it would have jackknifed and possibly caused a multiple vehicle incident. Thankfully I will never know for sure but I would never tow a glider trailer any distance without good brakes..

With a 11,500 tow vehicle and 2500lb trailers, brakes are almost irrelevant for
stopping the combination - I did the experiment on an out and return to Alaska.
And now, the tow vehicle is 13,500lbs - it's even steadier.

Stability is not an issue with the huge difference in weight and the long wheel
base (with four tires on the rear) of the motorhome. Also, I tow 60 mph, pass at
70, and "flutter speed" is well over 100 mph. The trailer has so little affect on
the motorhome, I can't feel what it's doing, not even if a tire blows (done that
experiment).

The best argument for brakes in my situation is dampening the swaying if the
trailer came off the ball, but I believe the chains are strong enough to withstand
the whipping that would ensue, and the motorhome is heavy enough to be easily
controlled during the stop.


Eric I was quite specifically not referring to ordinary trailer swaying instability. I was referring to the driver having to make an emergency stop while towing and the trailer starting to try to overtake the vehicle. The weight of the towing vehicle would be no help there.

wrote on 2/19/2019 12:59 PM:
On Tuesday, February 19, 2019 at 7:02:43 PM UTC, Eric Greenwell wrote:
wrote on 2/18/2019 9:58 PM:
I don't think disabling trailer brakes is a good idea. There is stability under heavy braking to consider not just retardation. I have twice, separated by about 25 years, had the situation of having to emergency brake on a motorway, the trailer start to swing out (not just sway) and then snap straight as the trailer brake bit fully. My impression was that if the trailer had been unbraked one or both times it would have jackknifed and possibly caused a multiple vehicle incident. Thankfully I will never know for sure but I would never tow a glider trailer any distance without good brakes..

With a 11,500 tow vehicle and 2500lb trailers, brakes are almost irrelevant for
stopping the combination - I did the experiment on an out and return to Alaska.
And now, the tow vehicle is 13,500lbs - it's even steadier.

Stability is not an issue with the huge difference in weight and the long wheel
base (with four tires on the rear) of the motorhome. Also, I tow 60 mph, pass at
70, and "flutter speed" is well over 100 mph. The trailer has so little affect on
the motorhome, I can't feel what it's doing, not even if a tire blows (done that
experiment).

The best argument for brakes in my situation is dampening the swaying if the
trailer came off the ball, but I believe the chains are strong enough to withstand
the whipping that would ensue, and the motorhome is heavy enough to be easily
controlled during the stop.


Eric I was quite specifically not referring to ordinary trailer swaying instability. I was referring to the driver having to make an emergency stop while towing and the trailer starting to try to overtake the vehicle. The weight of the towing vehicle would be no help there.

I misunderstood the situation you were describing. That's never happened to me,
even though I've had unbraked trailers from 4 different mfg over 17 years and 75+
thousands of miles around the North America, so I'm not concerned about it.

Also, I don't understand how the trailer could get very much out of line in my
situation: the more it yaws, the trailer tires will be directing back into line,
and the retarding force will be diminishing. The jackknifing I'm familiar with
involves very slippery pavement (ice or lots water - not the situation for 99% of
my towing), or the tow vehicle being pushed out of control (with 9,000 lbs on the
rear axle, it's not likely the 2500lb trailer can do that).

I still think your experience applies to people with lighter tow vehicles, and
they should cautious about disabling the brakes.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

On Saturday, February 16, 2019 at 4:21:22 AM UTC-8, Bob Youngblood wrote:
I am trying to get away from the surge brakes and has anyone converted their trailer to electric brakes?? Thanks

Does anyone know what a Komet trailer with a typical single seat seat glider weighs? Some states in U.S. require brakes if 1500 lbs or more (most are 3000lbs or more).

On Saturday, February 16, 2019 at 11:13:21 AM UTC-5, Richard Pfiffner wrote:
On Saturday, February 16, 2019 at 4:21:22 AM UTC-8, Bob Youngblood wrote:
I am trying to get away from the surge brakes and has anyone converted their trailer to electric brakes?? Thanks

Bob

I converted my cobra to Dexter Axle Torflex with electric brakes. I measured the axle bolt holes spacing, tire bolt scheme and distance from wheel to wheel. Purchased online from a trailer company they welded the brackets to fit. The easiest way is to take to a trailer dealer that carries Dexter Axles and have them replace the axle.
It was about 15 years ago as I remember $450 included shipping from Florida to CA. Call if you have questions.

Richard
www.craggyaero.com

Yes, thanks for the info. I did look into the Dexter Torflex axle and it does come with the electric or hydraulic braking capabilities. I will be doing some measuring and evaluating the situation in the near future. Another good feature of the axle and wheel assembly is that one no longer needs to look for Opel car wheels as the proper lug configuration. The Komet trailer company used Opel car wheels as their choice. I had to locate a wheel for a spare tire and it was difficult to find one.

Does anyone know what a Komet trailer with a typical single seat seat glider weighs? Some states in U.S. require brakes if 1500 lbs or more (most are 3000lbs or more).

From memory, our 1978 Komet with an LS-3 was about 1700 lbs.

Chip Bearden

Took my 1981 komet to a local trailer shop for adjustments and lube before a trip out west last summer. They said they had never seen such a contraption underneath it, and didn't have any way to replace parts. He thought it looked like some backyard custom made thing. Which is pretty consistent with what I've noticed about glider trailers, no two are the same. I ended up going to a new axle with electric brakes, which I was towing behind a 4runner. It involved quote a bit of creativity on the shop's end, and they did excellent work. Also involved bolting the sliding tongue down, since surge breaks were gone. It made a difference, simply because the 4runner wheelbase was pretty short. Getting passed by a truck or windy conditions tended to wag the vehicle a bit, regardless of trailer tongue loading. With the electric brakes, you leave the gain at 2 or 3, and if it starts swinging just squeeze a little manual brake pressure and it straightens right out. Now I tow behind a tundra, and forget the trailer is even attached. Another point is, during a long trip if something original komet fails, it'll be weeks before you're back on the road. With this one I could buy parts at Auto zone and wheels at Wal Mart if I had to. For me it was all about reliability and safety. But then again I also have a back up camera on my trailer wired to the tail light circuit and LEDs all over it. I think the total for the axle and brake swap ended up being about $1,600. Also it took me dragging it to 3 different shops before one agreed to be creative and work on it.

Jordan