Pulling stumps

[wroughtn_harv]

I hope you're right. But my bud was told by a mechanic at his dealer that the bumper I'd put on for him would preclude the air bag inflating because the switch depended upon the factory bumper moving just so far. And half the known world has to got to move before the force gets to the factory bumper on Flour Power.

If anyone has any more information on this I'd sure appreciate it.

Hell, I'll sleep better and maybe make some more bumpers!!!!

 

[bgott]

Well. I haven't been in the business for about four years but I went to a few airbag seminars before I "retired". I don't see why they would design a switch that depended on bumper movement. They have a switch behind the bumper that is the primary trigger and one that is up high on the firewall that is the arming trigger. The SIR ( Supplemental Inflatable Restraint) computer needs to see both switches triggered to activate the airbag. The system is not supposed to activate if the impact is off center 30 degrees from the centerline of the car. That is side to side or up and down. The field of operation would be a little hard to regulate if the switch depended on bumper movement. Also, if you ran into a pole in a parking lot and set the bumper in a little it would change the trigger point if you hit something while going faster.

My friend that manages a body shop is at the doctor today. I'll call and ask him tomorrow if any cars are using a bumper actuated system. I know for certain GM and Toyota use inertia switches and am 99.9% certain everyone else uses them too. Your buddy might have been talking to a lube guy that was masquerading as a master tech, trust me, that happens all the time!

 

[Soundguy]

I'm not privy to the exact workings of the airbag switch ( as stated.. most of us know the basics, etc )
But in case that the switch is somehow tied to movement of the front bumper, etc, why not add an energy transfer bar(s) that travels from the new bumber to the stock bumper. Should be just another few measurements, and some iron. Just an idea.

Soundguy

<font color=blue> "hope you're right. But my bud was told by a mechanic at his dealer that the bumper I'd put on for him would preclude the air bag inflating because the switch depended upon the factory bumper moving just so far. And half the known world has to got to move before the force gets to the factory bumper on Flour Power.
If anyone has any more information on this I'd sure appreciate it.
Hell, I'll sleep better and maybe make some more bumpers!!!! "

 

[bgott]

I'm sure this site isn't the last word on the subject but I figure that there was another type of switch it would list it. I think your biggest worry on building bumpers would be to not defeat the crush zone. If you look at the front part of the frame on most trucks and frame cars you will see a section that looks like an accordian. This is designed so the front of the vehicle collapses during a wreck, thereby absorbing some of the energy. You'd want to design the bumper to mount on the extreme front end of the frame rail. Of course, there are some guys that would want it tied to the crossmember to keep from screwing up the frame. They figure they'd heal after a wreck, frame repair would cost money!

<A target="_blank" HREF=http://www.howstuffworks.com/framed.htm?parent=airbag.htm&url=http://www.lemurzone.com/airbag/crash.htm>HowStuffWorks</A>

 

[lagrange11]

Harv,
Wanted to know if you could take a close up picture of the bottom of the stump / tree puller?
Thanks
Doug

 

[wroughtn_harv]

Here you go Doug.

Bear in mind this was done in minutes and only for purposes of demonstration.

What I tried to do was make the base where it would support the post in such a way as to let it swivel back and forth but not side to side. That's the reason for the saddle cuts in the pipe on the base and the saddle cuts ninety degrees off from that on the post. I did get lucky cause it appears to work just fine.

We could smear some pretty on it and make it into a real animal to work with.

 

[wroughtn_harv]

Wow, fast fingers foolin' up again. Darn, I hate it when that happens.

That first picture I took to show the pipe and brace in a ready position. What I wanted was to have the base made in such a way as to not need someone holding things in place until the tension was on the tow strap.

I don't know about you but if wife's baby brother was to get hurt while helping you with a contraption you'd made life would change around the house.

Hopefully here's the picture of the base and post.

 

[stovepoker]

That's quite a gizmo you put togeter, Harv. Bein' in a hurry,
I built your contraption using a length of 6" well casing welded
to the inside face of an old 20" split rim truck wheel. The outer face of the curved rim
rocks as the mast moves forward. I back the F600 flatbead up to it and chain the top end of the
mast to each of the front corners of the 16ft flatbed. I then
put the old girl in crawling tooth, let out the clutch, and don't
stop until the stump is wherever I want it to be. I use grade 80 lifting chain, so no surprises yet. The biggest one I've pulled yet was a 12 inch Oak. No problem with the truck or the rig, but it took a lot of beer and plenty of magic words to snake that chain thru the roots. Everything up here is rocks and clay. A great idea.....Thanks.

 

[wroughtn_harv]

I hope you have a good headache rack on that old Ford.

I am glad it works for you.

I think what surprised me more than anything else about it was the power transfered to the lifting motion instead of it just being a pulling motion.

I do wish you could post a picture of two.