Grapple Failure

[IslandTractor]

That is my perspective. I plan on keeping the grapple and reinforcing it if needed, to do the job I bought it for. Welding on some extra steel while everything is straight and true is a much easier prospect than repairing one that is already wrecked. I'd like to see them make an improvement to the product by upgrading to 1/4" steel and/or improving whatever else is causing these failures and thrive in business as a result but it is unreasonable, in my opinion, to demand they redesign the product to replace mine with a new and improved model, if they have not made the improvements already. If Whirlpool comes out to repair or replace a broken dishwasher, it would be unreasonable for me to demand that they redesign the dishwasher before replacing the broken one.

I agree that is a good solution for you if you are willing and able to do the necessary modifications. However IMO, until we learn that Wildkat has actually changed to 1/4" wall top tubing, anyone contemplating a grapple purchase should steer clear unless they 1) have a very light weight machine with limited loader power. Or 2) intend to give it the Lada treatment and put some reinforcement on that top tube before ever using it. As it stands, I wouldn't put one on my old CK20.

 

[ovrszd]

Since the cylinder is the thing that is actually creating the damage here, they should probably "downgrade" that for the 1/8 lite version as well.

That's the fix right there. Build a "cheap" version with 1/8" beam and smaller cylinder so it doesn't destroy itself. Problem solved.

When I'm building something hydraulic I just guess as to cylinder size. But if I was marketing a hydraulic item I'd contact someone like JJ or oldnslo and have them figure a cylinder size for me so my junk didn't destroy itself.

 

[J F]

No question Ralph was and still is an idiot. He gave us Shrub as his last great gift to the nation.

Compared to the current "gift", the "shrub" just keeps looking better and better.

 

[k0ua]

Compared to the current "gift", the "shrub" just keeps looking better and better.

No kidding, I didn't think much of the "shrub" at the time, but I would take him back now in a heartbeat.
I used to think Carter was the worse president we had ever had, but no... not so much any more.

 

[CalG]

That's the fix right there. Build a "cheap" version with 1/8" beam and smaller cylinder so it doesn't destroy itself. Problem solved.

When I'm building something hydraulic I just guess as to cylinder size. But if I was marketing a hydraulic item I'd contact someone like JJ or oldnslo and have them figure a cylinder size for me so my junk didn't destroy itself.

How would one EVER calculate the destructive loading on that top transverse member?

The failure was in the HAZ, a very difficult region to quantify. (What is the shear value within the HAZ?

Sure adding material will do in a "belt and braces" approach, but if a 2 inch cylinder will not work, how can one say a 1.5 inch cylinder will. Or, what value would one set the pressure regulation valve ?.... 2500psi? 2250? ... or start at 1000psi and see how things work out clamping on material wise. tuff call I would say.

Me? I'm using the T-LAR finite element analysis software to qualify all my fabrication efforts!

(T-LAR? = That looks about right!)

 

[TomSeller]

That's the fix right there. Build a "cheap" version with 1/8" beam and smaller cylinder so it doesn't destroy itself. Problem solved.

When I'm building something hydraulic I just guess as to cylinder size. But if I was marketing a hydraulic item I'd contact someone like JJ or oldnslo and have them figure a cylinder size for me so my junk didn't destroy itself.

The damage in the previous thread was not from closing the cylinder. It was from pushing with the lid. Granted you should not push on the lid but a little is unavoidable. They just need to use something besides pop can walled tubing.

 

[Zebrafive]

I know I came to this late.................. Checking online steel prices:

3x3x1/8 wall x 4ft weight 19lbs, cost $30.65 includes $5 cutting fee, no shipping fee

3x3x1/4 wall x 4ft weight 35 1/4lbs, $36.72 includes $5 cutting fee, no shipping fee.

16 1/4 lbs more metal for $6.07 more. Or $1.52 per ft.

Another thing about square tubing, wall thickness can be plus or minus 10%, so your 1/8" wall might only .113"

Source: The Best Place To Buy Metals & Industrial Supplies Online | Buy Metals Online | Buy Industrial Supplies Online | Cut to Size | No Minimum Order | CNC Laser Cutting | CNC Machining

 

[IslandTractor]

I know I came to this late.................. Checking online steel prices:

3x3x1/8 wall x 4ft weight 19lbs, cost $30.65 includes $5 cutting fee, no shipping fee

3x3x1/4 wall x 4ft weight 35 1/4lbs, $36.72 includes $5 cutting fee, no shipping fee.

16 1/4 lbs more metal for $6.07 more. Or $1.52 per ft.

Another thing about square tubing, wall thickness can be plus or minus 10%, so your 1/8" wall might only .113"

Source: The Best Place To Buy Metals & Industrial Supplies Online | Buy Metals Online | Buy Industrial Supplies Online | Cut to Size | No Minimum Order | CNC Laser Cutting | CNC Machining

Yep. Looks like saving $12-15 bucks per grapple is more important to some companies than quality.

 

[Red Horse]

I agree Wildkat is making an effort but replacing a Chevy Corvair with another identically flawed model doesn't make sense.

How do you draw that conclusion?

 

[Red Horse]

The damage in the previous thread was not from closing the cylinder. It was from pushing with the lid. Granted you should not push on the lid but a little is unavoidable. They just need to use something besides pop can walled tubing.

Agree 100%-although there are many whom have posted on this subject that insist its an over application of hydraulics.

Speaking from EXPERIENCE, I wrecked mine by doing something it was not intended to do- I had rolled the top grapple onto the edge of good sized boulder and was trying to drag it out of the ground-using my 60 horses and close to 6000 lbs of weight.

Now while I have been vocal in defending Wildkat-I got what I paid for and IMO you are dreaming if you think you have the right to get Big buck tractor quality (Deere/Kubota?) when you buy a Chinese Nortrac tractor or whatever they are called- I will say in my case thjey dropped then ball and it may well have been just a welder's error. check out attached shot. The cylinder attachment bracket did not have a full weld on it. Regrdless of 1/8th or 1/4" tube, this bracket had no benefit of the front of the tube as it was not attached!!