Lunette Ring Extension ?

[Artisan]

I found one of the extensions with pintle still on a truck that has cannibalized for parts. (80's vintage GMC Generals are hard to find) Couldn't get too close because it was covered in vicious blackberry vines & I didn't have a machete with me.

I did get a tape on it though & this one only extends about 4". The pintle has 4 bolts- I'd guess 2 1/2" on center vertically x 4" on center horizontally. I'll upload a photo when I get the blackberries off of it.

Driller if it is the PINTLE and it has 4 bolts it will not work. (My pintle has 2 bolts)
If it is the Lunette RING and it has 4 bolts it is close but I need more than 4 inches
but if four we are not far far 6 and I would love o see a pic.

No matter I SO APPRECIATE the effort...

 

[Artisan]

Sounds like an adapter plate could easily be made up.

A plate is easy to draw, and being fluent in AUTOCAD 2D it is a no
brainer but what is of concern is the bolts that connects it all.
Long bolts = Leverage, and Shear, are extremely powerful forces.

I expect to hit max 25,000 pounds easy plus I want at least a 1.5 overage

 

[DrillerSurplus]

A plate is easy to draw, and being fluent in AUTOCAD 2D it is a no
brainer but what is of concern is the bolts that connects it all.
Long bolts = Leverage, and Shear, are extremely powerful forces.

I expect to hit max 25,000 pounds easy plus I want at least a 1.5 overage

I agree, I'm sure Edison or GM had the extension engineered, but we don't know what parameters they used. What holds up for the first 500 miles might fatigue & suddenly fail at 600 miles. I'd be more concerned about the amount of tongue weight trying to bend the bolts rather than overall trailer weight. Some of those bumpy freeways around you could create shock loads that are many times the tongue weight -sort of hard to engineer for that.

The pintle is 4 bolt. I brightened the picture up and it looks like your 916 has a plate where pintle is mounted that is big enough for the bolt pattern. If you have access to a mag drill, it would be easy to install.

As I looked at the photo, I had another thought. I've used many commercial trailers and on many of them the adjustment plate also goes below the trailer frame to allow hooking up to truck with a lower pintle height. In your photo, the lunette ring is on the lowest position, what trucks are going to have a pintle mounted higher than the 916's? Maybe a clean cut is the way to go, you would still have some height adjustment.

I'll post photos of Edison truck extension once I get the blackberries out of the way, might just pull the thing off.

 

[Artisan]

Yes Driller, all points valid. If there were any easy fit extension I would go
that route but looks like I am going to be chopping this thing off. I just
hate to do stuff like that for fear of someday wishing I had not done it.
True, an M916 is a monster and tall but they made this thing that tall
so there must be some way bigger trucks maybe we do not know about.

I just did the calcs. If the truck and trailer stay on flat level ground.

If I cut the riser 0.2540" above the top of the next set of tapped holes
leaving me one adjustment "UP" , meaning a pintle TALLER than an M916
I would clear by 0.260" at a 43Degree angle. Again if in a perfect
world on FLAT ground.

I am not sure that is enough if I want to be carefree and go offroad.

If I were in the bottom of a dip in the road and the tractor was at
a 21.5 degree angle up and if the trailer were at a 21.5 degree angle
azz high I would clear but if were askew (if the raod is not perfectly flat)
it would hit...

krap. Not sure now. I may need to chop it off leaving no adjustment.

 

[gimpyrobb]

It takes 16,000lbs to shear a 16penny nail. Do you know how much it would take to shear whatever size bolts hold that on? I understand being cautious, but, uhm, I think you are too worried about it. ANyhoo, its not my worry, carry on!

 

[Artisan]

The math / CAD drawings didn't lie. I could easily in the future
place the truck in a nose up attitude of 21.5* and the same w/ the
trailer but azz high and one little bump and I would be pounding
one into another so off it comes. I just grabbed my Skillsaw
and yelled "This one is for the Gimp!" and Lorena'd that
pupply clean off. WHACKO!~

(makes the hair stand up on my neck! )

 

[RustyM923]

Did the blade complain much?

 

[Artisan]

Did the blade complain much?

That blade is AWSOME. I have cut maybe 30 lineal feet of .25" steel plate w/
it prior to this and it could do 50 more of these I am sure. No real
blatent signs of giving up yet. Incredible, a Skillsaw to cut 1" steel
plate...Welcome to the 21st Century.

 

[DrillerSurplus]

WOW! Who makes that blade? I need one.

 

[Artisan]

I have lots O tricks.

These blades have been around for years actually.

I have a 48 tooth and I have done as I said w/ it.
I believe now they have a 38 tooth designed for thicker
metals. My 48 is sweet though.

I cut thru that 1" thick slab in 2 passes, I could have done
it in one. WEAR SAFETY GLASSES and best to put these blades
in a 100% shrouded saw and not a skillsaw, but it works.

CLICK HERE and then select the different tooth counts, 48 and 38
and you better look at them all to be sure.

http://www.homedepot.com/p/qv/203162373

There is a Home Page for Diablo too, that would be the best place to
look for the latest and greatest Driller.

 

[DrillerSurplus]

It is a moot point now, but I saw this lunette extension on a trailer today so I thought I'd post it for future reference.