Go Back OFN Forums > Fabrication > General Fabrication

General Fabrication Any Fab that does not fit into another Forum


General Fabrication Any Fab that does not fit into another Forum

Reply
 
Thread Tools
  #1  
Old 08-17-2015, 02:05 AM
stock93's Avatar
stock93 stock93 is offline
Master Fabricator
 
Join Date: Dec 2006
Location: Huntsville, AL
Posts: 160
Grapple

Started fabricating a replacement jaw for a friend's torn up Branch Manager Grapple. He has torn up two of the smaller jaw so we decided to do a heavy duty replacement. My BMG is tearing up in the same spot so I figured it would be good to have a heavy duty replacement. I was doing alright until I ran out of welding wire. I still have to get some tubing for the bushings to mount the cylinder and the pivot.

Drawing this up in CAD was a real pain. I was trying to match an existing part. The jaw wasn't just a couple of arcs. There were some straighter section to allow for more material. I ended up getting it close then cutting it out of 16 guage so I could lay it on the broken one to check my drawing. I think I cut 5 or 6 of these tweaking it each time until I was happy with it. Here's the jaws cut out of 5/16" plate.


The main problem with the jaw's design was the original doesn't have enough plate to keep it from flexing sideways under a load. All three of the original design have bent just behind the tip. I'll try to remember to take a picture. It's not pretty. I designed two gussets that run most of the length of the jaw. I really like being able to cut bend lines with the plasma. It makes tweaking stuff around to get it to fit really easy. We tacked the tubes into the side plates to keep the holes lined up.


Tacked both of them in place to space the side plates apart and flipped them up to weld.


I got the outside all welded up. Unfortunately I ran out of wire part way through the inside. I really need a bigger mig welder for doing this kind of stuff. My miller 175 was turned up to 10 and I wouldn't have minded if it was a little hotter. I'm surprised I didn't trip the thermal cut out.
Reply With Quote
  #2  
Old 08-17-2015, 09:29 AM
R.DesJardin's Avatar
R.DesJardin R.DesJardin is offline
Designer & Builder
 
Join Date: Jul 2009
Location: Clarkston, WA
Posts: 365
Cool project, good tip using 16 ga to cut samples. Looks like it should be rigid. You didn't make it so stout that something else will break now did you?
__________________
Need, Design, Build, Use, repeat........
http://www.radesignsproducts.com/
Reply With Quote
  #3  
Old 08-21-2015, 10:45 AM
stock93's Avatar
stock93 stock93 is offline
Master Fabricator
 
Join Date: Dec 2006
Location: Huntsville, AL
Posts: 160
It's probably going to be the strongest part of the whole thing now. Here's the old messed up one. I had to order some 1.5 .250 wall tubing as I didn't have any or any 1.5 bar in stock.

Reply With Quote
  #4  
Old 09-05-2015, 02:29 PM
stock93's Avatar
stock93 stock93 is offline
Master Fabricator
 
Join Date: Dec 2006
Location: Huntsville, AL
Posts: 160
Tubing came in the other day for the pivots so I got those machined out and welded on.




Tried fitting it on the grapple. It fit without any issues at all.

Reply With Quote
Reply

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 03:20 AM.

Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Template-Modifications by TMS
Copyright 2012, Offroad Fabrication Network