Cobra trailer skid wheels

Anyone know if a Cobra trailer is strong enough to allow it to be supported by the hitch and skid wheels on the aft end? And anyone mounted wheels in place of the skid pads for getting into steep angle

No experience on a Cobra, but my trailer had wheels on the rear when I bought it. They were constantly getting banged about, would develop worn flat places, etc. After replacing several sets, I put some McMaster Carr rubber bumper blocks... They are great.... If the rear does go down it absorbs the shock and they are shorter than the wheels, so they don't hit things as often.

YMMV

Eastern Sailplane, Cobra dealer, told me they are designed to withstand contact at only the hitch and rear end skid pads. The skid pads seem to work just fine to protect the trailer, but sometimes leave gouges in the pavement. Haven't had to replace them in 60,000

I put 2 inch iron CASTERING wheels on my trailers. The castering wheel is mounted to a 1/4 inch plate that is mounted to the bottom of the trailer in place of the skid. This has worked well for me during the last 30 years or so. Obviously many trailers get by with just a skid, so the castering wheel is not REALLY required.

The most usual time to drag the back of the trailer is when coming out of a gas station. During this action I am usually turning. When the skid is dragging in a sideways motion, I think that it can put an adverse load on the trailer, hence the castering wheels.

The wheels protrude only slightly more that the usual skids. In some cases the Cobra factory skids are not big enough. If you have the stabilizing jacks on the rear of the trailer and go through a big dip, the jacks can be damaged.

Duane

You need to do a search through google about the thread

Cobra tongue breakage

If you love your trailer, or value the contents of your checking account, you will choose to make a greater effort to find a flatter slope into a gas station. . . . .

Cindy B

Duane, thanks very much for your response. This tells me that you have had no trouble when the weight of the trailer is momentarily supported by the hitch and the aft edge of the trailer, whether by skids or wheels.

My reason for the question and concern, and why wheels will be necessary, is that I intend to store my glider in my garage which has a steep upward pitch leading down into it. These trailers are so long that every time it goes in or out it will necessarily be supported by the wheels and hitch, possibly lifting the main wheels entirely off the ground. It is smooth concrete so there's no snags, but still, if the assembly can't be supported in this manner then I'm in trouble.

If anyone has pics of their wheel installation (how they are mounted) I'd sure appreciate it.

Randy Lervold Vancouver, WA

There is also the issue of the trailer rolling sideways into ??? (a car coming into the parking lot while you are going out. Castered wheels can only be presumed to 'caster', allowing the trailer to move sideways as well as forwards.

Is there any evidence to suggest that is what caused the tongues to break or crack? Everything I heard indicated it was fatigue, not

Eric wrote>>>>>>>>>>>>>>

Dale Bush cracked his cast trailer hitch when the jack wheel hit as he drove out of a gas station. If *fatigue* is the cause, why are the new tongues failing? I would expect the older tounges to show a fatigue problem first. JJ Sinclair

......... If *fatigue* is the cause, why are the new tongues > failing? JJ Sinclair<<<

Have you heard of 'new' Cobra tongues failing? If so, please start a new thread and lets us know what you know about the failures.

It just occured to me that the problem may be in the term *Metal Fatigue*, we probably should be saying *Metal Stress*. Metal Fatigue conjures up the vision of those brave fire tanker pilots making a drop in the Sierras. The wing of their 30 year old C-130 failed because of metel fatigue caused by thousands of cycles over many years. Metal Stress, on the other hand can occur in a very short period of time by simply bending the metal past its yield point and it will crack and fail in as little as 10 or 20 cycles.

I just did it with a push rod held in a vice. The mild steel push rod was much smaller than our Cobra tongues.but its diameter and wall thickness were proportionately similiar to the Cobra tongue. When I bent it past its yield point, the compression side formed a little bulge. With repeated cycles a small crack appeared on one side of the bulge after only 7 cycles. A few more cycles and the crack went half way around the tube. On the twenty-first cycle it broke in two pieces.

So, what can we do to prevent this from occuring? First look at your jack wheel and or skid plate below the hand brake. If it has skid marks on it, then you got the problem. The first thing I did was to remove the jack & wheel when traveling. Then I noticed the hand brake skid was scraping. You can raise the ball height (hitch with a shorter drop) This will cause the far end of the trailer to drag, but at that distance from the tongue, it can take it and won't cause tongue failure. Or. I placed a heavy duty caster on the bottom of the bolt that holds the ball. NOTE, this is on the motor home side, placing a caster or skid on the trailer tongue will only provide a new fulcrum around which to bend your tongue! When I exit the gas station the caster hits first and doesn't allow the rear end of the motor home to continue to drop as the rear wheels roll through th curb. JJ Sinclair