Digger/excavator post driver

[Tentman]

Gidday Guys (after a long silence)  .  Last time I was on here was when I was developing a vibrating plate driver with an integrated auger drive - for my 2.5 tonne machine.  It's been very sucessfull but occasionally I do need a hammer type driver - so Im gonna build one, they are unobtainable down here in New Zealand.

 

So after looking at the great ideas incorporated in this thread, is there any necessity or advantage to have the mast articulated at 90 degrees to the crowd - or do you just push a post back to plumb with a bit of swing and or leveling the machine with the blade?

 

Thanks

Foster

[doobin]

10 hours ago, Tentman said:

Gidday Guys (after a long silence)  .  Last time I was on here was when I was developing a vibrating plate driver with an integrated auger drive - for my 2.5 tonne machine.  It's been very sucessfull but occasionally I do need a hammer type driver - so Im gonna build one, they are unobtainable down here in New Zealand.

 

So after looking at the great ideas incorporated in this thread, is there any necessity or advantage to have the mast articulated at 90 degrees to the crowd - or do you just push a post back to plumb with a bit of swing and or leveling the machine with the blade?

 

Thanks

Foster

On that size machine the slew force is a limiting factor. You might get a bit more power if you have a tilt on the mast and the foot on the ground, but it's more cumbersome that way I find.

[Tentman]

Gidday all.  The post driver mast is made on a 100x100UB.  I'd like to be able to adjust the height of the hitch so am thinking of a "sandwich clamp" to get onto the mast.  Then following @Malus excellent approach I'd make up a 3 piece adapter bar, hitch and spacer, with the same hole pattern all round so I have heaps of options to mount it.  Thoughts?

 

Hey and I hope I'm not at odds with the etiquette for this forum buy adding to this thread.

 

Cheers

Edited March 3 by Tentman

[Tentman]

Everyone likes a picture so here is one of the canidate driver.  The 3 point linkage and foot are on the same pin, just pull it to lose them!

Edited March 3 by Tentman

[doobin]

5 hours ago, Tentman said:

Everyone likes a picture so here is one of the canidate driver.  The 3 point linkage and foot are on the same pin, just pull it to lose them!

Looks like you will be ok fabbing, but I’d start with a better candidate . Cycle times with the winch won’t be great, nor will longevity of the rope (uncontrollable bird nesting). There’s also no post cap, which is pretty essential for digger work. 

[Tentman]

The cap can be built from the existing post holder, which were common when these were built.  I haven't run it yet, if it's too slow on the lift it'll get converted to a ram type.  It does have a very simple but clever arrangement to control the rope in under the cover.  I'm not to concerned if it is OK, I only paid scrap price for it and have a good straight mast, hammer of the correct weight and a prefabbed 3 point hydraulic hitch for my $$$

[Tentman]

Gidday - ran the "new" driver up today and it has a lot of potential.  The up speed is just fine at both idle and half revs.  The down seems a tad slow and the motor is definitely cavitation as it drops. Since I want electrically actuated valving then I think it can be considerably improved by a more sophisticated valve arrangement whereby oil is directly bypassed back to the "down" side of the motor.  There was no sign the winch birds nesting but early days eh.

[Malus]

@tentman looking good but like you say looks a bit slow on the way down. Have you put it to use yet? I'd say a hydraulic ram arrangement will be better than the winch, the winch could be repurposed. Would make a really handy timber winch if it's strong enough.

 

I guess you're planning on controlling it from inside the cab? It's a lot quicker than way and a lot quicker than a tractor knocker. I tend to run out a string line between strainers and then stab a good 10 stakes in, jump in the digger and drive them inm saves getting and out for each stake.  The downside is it's difficult to get posts in absolutely vertically if you're working on your own. Just like a tractor knocker the posts often go in nice and plumb but as soon as you lift the post cap up the post springs off to one side, I guess that depends on what your ground is like.