Looks like you got your answer, we sometimes do this, usually a 2mm orifice. If you can’t get one off the shelf, we tap out a 3/8” nipple & loctite a drilled grub screw in. Make sure it’s in well as you don’t want it slipping into your cylinder! It generates minimal heat as it’s not a constant flow tool, like a trencher going through a restriction. Also possible to get more technical - put in adjustable pressure compensated flow control valve but I like simple!! Cam
bmg hydraulic lines
- Thread starter treebing
- Start date
Looks like you got your answer, we sometimes do this, usually a 2mm orifice. If you can’t get one off the shelf, we tap out a 3/8” nipple & loctite a drilled grub screw in. Make sure it’s in well as you don’t want it slipping into your cylinder! It generates minimal heat as it’s not a constant flow tool, like a trencher going through a restriction. Also possible to get more technical - put in adjustable pressure compensated flow control valve but I like simple!! Cam
flyingsquirrel25
Carpal tunnel level member
- Location
- South East, PA
Just noticed your picture here. I’m glad I’m not the only one that had this problem. BMG should put a lock nut under there, the double nut just doesn’t cut the mustard.
As for routing I have very similar set up to colb. A bungee at the cross wrapped super tight. The hoses in front of the cross are actually fairly short to prevent tangling with the upper pivot of the grapple arms. I learned the hard way that’s not good to have happen. Tore the pressure release quick connect right out of the DW connection block. $200 repair on a holiday weekend, but Jesco saved the day big time.
Dave was straight up about it. He sent out a new nut and bolt. My local Kubota shop installed it since I lagged on it for a couple weeks. Fortunately, my grapple was low when it fell off, so the hoses didn't take the weight of that log and grapple falling off...
Dave is recommending a standard nut with a tac weld. Mine was a fancy looking locktited nut, but the locktite obviously lacked stamina in this application.
flyingsquirrel25
Carpal tunnel level member
- Location
- South East, PA
Yea my new BMG came with a split nut and a low profile nut. When I finall got sick of messing with it I found the knuckle I replaced on the old grapple and robbed one of the lockers off that. Haven’t seen an issue since!
southsoundtree
Been here much more than a while
- Location
- Olympia, WA
When mine was coming loose, I could see a small gap developing. By the time it is falling off, isn't there a TON of slop and gap?
I think that when it happens the first time, the gradual process is deceiving. Yes, it was floppy, and bmgs are floppy to start out with. The reinstalled bolt/nut on mine is not all the way up and tight. I think the sloppiness is limited by the hole in the clamshell housing and the diameter of the bolt - same slop no matter how far down it you are...
southsoundtree
Been here much more than a while
- Location
- Olympia, WA
I could see space between the two 'halves' that wasn't there before. I tightened it up, but it came back. Maybe a "heavy" quarter inch.
BM sent me 2 nuts. Seems to be good mostly, but a looser than when installed, which I need to tighten.
To me, it was very noticeable at 1/4-3/8", maybe a little more gap, possibly.
Seems like the nuts are an inch tall, each. Would it not need a 2 inch gap before the grapple fell off?
BM sent me 2 nuts. Seems to be good mostly, but a looser than when installed, which I need to tighten.
To me, it was very noticeable at 1/4-3/8", maybe a little more gap, possibly.
Seems like the nuts are an inch tall, each. Would it not need a 2 inch gap before the grapple fell off?
Yes, 2 inch gap. You're absolutely right that it happened right in front of my face. It's just that I did not expect it and it happened over the course of several weeks/months. A gradually unscrewing grapple is preventable in the design phase, and has some potential consequences. I didn't expect that to be an issue and formed my reality around that. Not knocking Dave, it's just easy to see that flaw in retrospect, and perhaps my cognitive disconnect as well.
flyingsquirrel25
Carpal tunnel level member
- Location
- South East, PA
No worries man I dropped mine off too in the first month after taking it off the shipping pallet. I had the cognitive failure as well. Lucky nothing broke. But who would have thought... every other nut on the thing is a lock nut you would assume the one that is a *#@^& to get to would be the same. The last time I noticed it it got a locker the next morning when we came back to the job.
Maybe that’s why all these guys like the wheel loaders so much... they pay so much attention to every bolt on their machine they loose sight of what they are doing and tear the grass up!
.No worries man I dropped mine off too in the first month after taking it off the shipping pallet. I had the cognitive failure as well. Lucky nothing broke. But who would have thought... every other nut on the thing is a lock nut you would assume the one that is a *#@^& to get to would be the same. The last time I noticed it it got a locker the next morning when we came back to the job.
Maybe that’s why all these guys like the wheel loaders so much... they pay so much attention to every bolt on their machine they loose sight of what they are doing and tear the grass up!
Lol, you might be on to something... I don't know much about nuts other than my own, but I think mine originally came with a non-standard-looking nut - might be a lock nut. I think that the tack weld spec that Dave prefers now is due to the failure of locking nuts to keep locked over time, but I may be misunderstanding something. I owned mine for 3+ years before it came off. Not sure when it started coming off...
flyingsquirrel25
Carpal tunnel level member
- Location
- South East, PA
The tack weld would certainly work but as the rotar wears you have no course of action to tighten it because you ain’t gonna grind it off up in there. 
Merle Nelson
Been here much more than a while
- Location
- SF Bay Area, CA
Military and aviation use nuts with codder pins or wire alot. Would prevent loosening, leaves easy ability to tighten up.
I think my Kubota guys may have put in a coder pin instead of tack welding. They thought it was a better solution and I deferred to them since Dave did not say anything about that, bad or good. I haven't looked at it yet. The tack weld would be accessible if one removed the hydraulic cylinder. I was too chickensh*t to delve that far in so I dropped it off with Kubota dealer. Now I'm poking around my new used dump roll off trailer's hydraulic pump this weekend, so so much for chickensh*tting on the grapple repair, lol.
Merle Nelson
Been here much more than a while
- Location
- SF Bay Area, CA
Ha. Which roll off trailer, MaxxD?
U-dump. Local company. I can pick up my new cans to avoid shipping fees.
What do you like about the MaxxD?
And for $5500 with a horrible can, it was hard to pass up!
Merle Nelson
Been here much more than a while
- Location
- SF Bay Area, CA
Their trailers are well built in general. I think the cans are too light for my taste in tree work. Nice you can do local. Probably get more possibility for custom influence too. I'll look them up for fun.
Merle Nelson
Been here much more than a while
- Location
- SF Bay Area, CA
Ahh great price. I watched used dump trailers for months - no deals.
Hi Guys, talking about the swivel section. To my customers in Australia we sell an encapsulated pin, this way there is no way it can fall off accidently as its not held by a nut (well not in a vertical plane). It has a large surface area to wear. It isn't serviceable but lasts for many years. All other bolts we use a combination of split pin with castle pin, roll pin or similar to retain a shaft in place. Dave from BMA has actually helped us out a lot along the way.
Attachments
New threads New posts
-
test
-
-
-
-
Light 14 or 16" narrow kerf bar for 200t or 201t- Started by southsoundtree
- Replies: 9
-
-
