Broke my grapple ( Am I the only one?)

[LouieJunior]

I recently bent the tip of my grapple's clamp arm. I am usually pretty careful not to apply a heavy load to the upper clamp assembly. Not sure exactly when it happened -- just noticed it was bent at about a 45 degree angle.

Any suggestions on how to easily straighten this out?

 

[Jeepnford]

I recently bent the tip of my grapple's clamp arm. I am usually pretty careful not to apply a heavy load to the upper clamp assembly. Not sure exactly when it happened -- just noticed it was bent at about a 45 degree angle.

Any suggestions on how to easily straighten this out?

Maybe heat with a torch and bend it back, possibly weld a gusset on the inside of the tine for reinforcement (if there's room). It would likely bend easier the next time and start to crack without the reinforcement.

 

[Dadof3]

Heat it and hit it.

 

[k0ua]

If you have no way to heat it, you could do it cold. Remove the grapple arm and put it flat on your anvil and put on some hearing protection, wail away with at least a 3 pound and preferably a 6 pound hammer, checking every lick or 2 to not over hit and curl it the other way..Heat is better and easier but you can get by if you have no torch. Hit intelligently and carefully.

James K0UA

 

[GregbkH]

Looks professional. Are you concerned about the two upper jaw end brackets on the same flimsy tube?

I'm not too concerned about the end brackets yet. They have shown no signs of wear or fatigue.

 

[IslandTractor]

I recently bent the tip of my grapple's clamp arm. I am usually pretty careful not to apply a heavy load to the upper clamp assembly. Not sure exactly when it happened -- just noticed it was bent at about a 45 degree angle.

Any suggestions on how to easily straighten this out?

I've done that too with my Millonzi. Heat, straighten and add gussets just as Jeepnford suggested.

 

[Mike476]

I'm not too concerned about the end brackets yet. They have shown no signs of wear or fatigue.

Did you have to elongate the center pivot pin hole to get it to line up with the two outers?

 

[GregbkH]

Did you have to elongate the center pivot pin hole to get it to line up with the two outers?

No, all I did was grind a 1/4" off of the center brackets and the holes lined back up .:drink:

 

[JFS2295]

To paraphrase Louis Renault: “I'm shocked, shocked to find that my $500 grapple is going to break!”

Come on guys, the reason that the grapple that I bought weighs so little and the cost was low was minimal engineering and materials. This is a design laid out by a couple of guys in a welding shop, not with a PE going over the calculations for all contingencies. I agree the stress loads at the cylinder mount were not considered and will be modifying mine when I have the time.

Plus pushing over a tree with the front of the grapple is the worst bending load you could put on it. I’m sure the thought process was only for grabbing things with the grapple upper jaw.

 

[IslandTractor]

To paraphrase Louis Renault: 的'm shocked, shocked to find that my $500 grapple is going to break!?/P>
Come on guys, the reason that the grapple that I bought weighs so little and the cost was low was minimal engineering and materials. This is a design laid out by a couple of guys in a welding shop, not with a PE going over the calculations for all contingencies. I agree the stress loads at the cylinder mount were not considered and will be modifying mine when I have the time.

Plus pushing over a tree with the front of the grapple is the worst bending load you could put on it. I知 sure the thought process was only for grabbing things with the grapple upper jaw.

I agree with one of your points, that pushing over a tree with the upper grapple arm as the contact point was a mistake. However we all make mistakes and suffer the consequences. I could bust a $3000 grapple just as easily by applying force where it was not designed to resist.

The light duty grapple design is fairly standard, well worked out over years by many different manufacturers. Was it designed by a team of nerds at NASA or Toyota, no, it is an evolutionary design born of practical experience. I rather doubt the original Bush Hog design was worked out on a Cray computer either. As I'm sure we all know by now, the upper pivoting arm of any grapple is designed only to clamp not push so even if the grapple had been designed by a team of German mechanical engineers something would have bent or broken. Maybe what we need is some equivalent of replaceable shear bolts worked into the design.

Regarding materials, this manufacturer skimped on the 1/8' wall tubing. Mistake. However, my $500 very similar grapple from Millonzi has 1/4" top tubing so I'd say that Wildkat's error was either not dropping one or two of the bottom tines or adding $50 to the price tag and instead using heavier duty top tubing. There is nothing cheap or untested about 3/8" bottom tines or the way that the upper grapple arm is made or attached. Upper grapple tips can bend on rocks or with extreme twisting force if ungussetted. Easy fix.

Before anyone goes running off to buy a "quality" engineered grapple like a $3000 800lb Anbo, do a little research on what CUT owners with cheap 48" light duty grapples think about these implements. I think you will find the great majority quite happy and more than a few that feel it is the single best implement investment they have made. You'll also find a few folks who did spend a lot on Anbos and then twisted them too.

I'd write this episode up as providing two "live and learn" lessons. 1) Manufacturers shouldn't use 1/8" tubing unless they do invest in more engineering design work and 2) operators need to understand the risk of allowing the upper grapple arm to be the primary contact point between a powerful tractor and a solid object. The manufacturer's error was one of commission and they really should correct it. The operator's error was obviously one of attention ommision and the type of thing that we all are capable of doing. If the top tube hadn't busted and force continued to be applied, I would guess that the next thing to fail would have been to twist the upper grapple side arms themselves. Not as easy a fix.

 

[JFS2295]

So far the pictures / text of these two different manufacturers look like the issue is the load from the locked hydraulic cylinder due to forces trying to open or close the upper jaw, using the rear cylinder mount arm as a lever. So much of the force is being transmitted to the cylinder mount rather than all of the three hinge points.

The Millonzi was built stronger at the upper tube with the 1/4" box tube for sure, and probably the best way to modify the unit would be a complete replacement of the upper tube, not something that is practical in the field. But Millonzi labor and materials cost back when it was purchased for $500 is certainly not the same as the pricing when these were purchased, so I would counter the Millonzi is a higher priced / class unit.

It's possible that between these two different suppliers of broken grapples that one just copied the other ones design rather then doing the engineering, or trying to get a hold of the older Millonzi example.

But we still have to come back to what these were designed to do which was not be a bulldozer.

This guy may (or maybe not) have put more thought into these pushing on trees based on the grabbing teeth. He seems to be proud of thick steel.

www.TheRakeShop.com / Root Rakes Grapples Attachments & Skid Steers

 

[IslandTractor]

So far the pictures / text of these two different manufacturers look like the issue is the load from the locked hydraulic cylinder due to forces trying to open or close the upper jaw, using the rear cylinder mount arm as a lever. So much of the force is being transmitted to the cylinder mount rather than all of the three hinge points.

The Millonzi was built stronger at the upper tube with the 1/4" box tube, and probably the best way to modify the unit would be a complete replacement of the upper tube, not something that is practical in the field. But Millonzi labor and materials cost back when this was purchased for $500 is certainly not the same as the pricing when these were purchased, so I would counter the Millonzi is a higher priced / class unit.

It's possible that between these two different suppliers of broken grapples that one just copied the other ones design rather then doing the engineering, or trying to get a hold of the older Millonzi example.

But we still have to come back to what these were designed to do which was not be a bulldozer.

This guy may (or maybe not) have put more thought into these pushing on trees based on the grabbing teeth. He seems to be proud of thick steel.

www.TheRakeShop.com / Root Rakes Grapples Attachments & Skid Steers

The difference in price between 8ft of 4x4x.125 and 4x4x.25 is only about 40-50 bucks retail. I'm sure a manufacturer doesn't pay more than that to upgrade. So perhaps $500-600 is a bit too cheap in today's $$ but if WildKat can make a profit selling them at $600 then they can upgrade the steel and make the same profit at $650. These are still prices that are half of what you pay for most similar size grapples so they are still a deal.

I agree completely these are not designed for bulldozing. Good thing because CUT FELs are not designed for bulldozing either. Bulldozers have short stumpy arms not long delicate ones designed to lift stuff into trucks. Use a boxblade to bulldoze if you must.

 

[Missouri Pioneer]

Haven't had that problem yet, but if I do, seems like a pretty simple fix. I still love my WildKat and would buy one again.

 

[whitedogone]

Haven't had that problem yet, but if I do, seems like a pretty simple fix. I still love my WildKat and would buy one again.

What he said

 

[foggy1111]

Haven't had that problem yet, but if I do, seems like a pretty simple fix. I still love my WildKat and would buy one again.

I have a Gator / Markham grapple.....and I kinda agree with what you say here. However, if EVERYTHING we buy had to be re-designed / re-engineered, then we'd all be full-time blacksmiths. Some companies just dont get it....some of these grapple manufactures are those kinda companies IMO. All about price first - quality second.

I like my grapple and the price I paid too....but would rather pay a bit more for a better designed one.

 

[IslandTractor]

I have a Gator / Markham grapple.....and I kinda agree with what you say here. However, if EVERYTHING we buy had to be re-designed / re-engineered, then we'd all be full-time blacksmiths. Some companies just dont get it....some of these grapple manufactures are those kinda companies IMO. All about price first - quality second.

I like my grapple and the price I paid too....but would rather pay a bit more for a better designed one.

I agree. The WildKat grapple has a simple flaw that the manufacturer should fix. 1/4" rather than 1/8" tubing would cost less than $50 extra and could easily be passed on to the customer as there is no less expensive grapple on the market. I don't have trouble imagining why they chose the 1/8" originally but now there is clear evidence it is the Achilles heel on an otherwise fine product so the manufacturer should change it.

 

[BigGuy]

Haven't been online for a while, but bought a Wildkat grapple a few weeks ago and had the exact same problem. I did as the OP did, pushing against a tree and not noticing the fact that the top of the grapple contacted the tree first.
After about 15 minutes of work, the grapple would not close anymore and I saw the bent bracket.
I sent pictures to Wildkat, asking them for input and they offered to send a new one and pick-up the damaged one right away, on their dime!
I agree that the top tube should be heavier, but "s..t" happens and in my opinion they made up for it with excellent customer service and fast turnaround time.
I will be much more careful and I won't be using it to push against trees, at least not with the grapple open. And when time permits, I plan on reinforcing the area of the cylinder mount, too.

 

[IslandTractor]

Haven't been online for a while, but bought a Wildkat grapple a few weeks ago and had the exact same problem. I did as the OP did, pushing against a tree and not noticing the fact that the top of the grapple contacted the tree first.
After about 15 minutes of work, the grapple would not close anymore and I saw the bent bracket.
I sent pictures to Wildkat, asking them for input and they offered to send a new one and pick-up the damaged one right away, on their dime!
I agree that the top tube should be heavier, but "s..t" happens and in my opinion they made up for it with excellent customer service and fast turnaround time.
I will be much more careful and I won't be using it to push against trees, at least not with the grapple open. And when time permits, I plan on reinforcing the area of the cylinder mount, too.

Nice to hear how Wildkat responded. Did they mention anything about using heavier gauge tubing in the future?

 

[crazyal]

Seams to me the real question is if you use the grapple as intended then would it break?

 

[IslandTractor]

Seams to me the real question is if you use the grapple as intended then would it break?

Bumping into a tree with the top grapple is not evidence of abuse. Grapples are not dainty tea sets or delicate race cars. Any grapple should be able to tolerate an occasional bump just like it should tolerate an occasional off centered load or impact. Grapples should bend not tear apart when pushed past designed use. Granted these are the economy versions but that refers mostly to the 48" width and single top grapple arm. Other economy or light duty grapples of nearly identical design (eg Millonzi) have heavier tubing and as far as I know nobody has had a similar failure.