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Slipster

hydraulic Post Knocker

And for my next project im going to attempt a hydraulic post knocker. During the past ten years My sons and I must have manually knocked around 1000 3 inch posts and after every field I have told them "that's it no more" I have just acquired another 5 acres that needs around 100 posts and stock fence. This time I really do mean no more manual knocking    
My knocker will be mounted on the front of my tractor loader this way I cant easily adjust the height and front to back angle, most post knocker are rear mounted I assume its because this way the manufacturer can sell to any tractor owner rather than limit sales to those just with loaders.
Watch this space
emsley

Like it    
12Bore

I would say that that should keep you out of mischief, but...
Have fun - and don't forget the pics!
sod

Also on back you can adjust the angle if the ground is not level by arm adjustment or top link
brummie nick

I seem to remember one being used on 'Countryfile' looks like it saves a lot of hard work, the sons will be very pleased.
magnet

Have you ever tried pushing your posts in with the front bucket?....Magnet
Pinpoint

Hi Slipster ....just browsing and found a vid of a home built front end knocker,  
I think the chap must have a death wish, he has put some thought into it but surely the mast should have gone down and sat firmly on the ground for stability.  His carriage with the swivel and top link to adjust left and right look pretty straight forward to make.  Just a bit of food for thought.  
Hope the link works....

http://m.youtube.com/watch?v=NP1b...op_uri=%2Fwatch%3Fv%3DNP1bIvvSX98
Slipster

The guys idea of a pipe inside a pipe was one that I looked at for side tilt movement however I decided to fix mine and not have side angle hope I haven't made a mistake but I only want it for 3 inch post and drive them in 18 inches so my thinking was I could adjust the post and the land is pretty level. I at a later date I need side angle then I will add it. The good thing about being front mounted is the height and front to back angle are already on the loader. Ive made a start and tacked most of it together, the most awkward part was getting the angles right for the arm but it now looks as though it going to work. Will take some pics in a bit.
Slipster

magnet wrote:
Have you ever tried pushing your posts in with the front bucket?....Magnet


The problem I have is that my loader lift arms are single acting and rely on weight of the arms to lower and so you can't push down the bucket is double acting but if you push down with the bucket it just raises the arms.
sod

Don't have photos but we made one for a digger we had once just got a petrol powered plate compactor and fitted to arm, Started motor then put on post in it went   But here they don't go through the rocks so it isdig a hole. Borers are hard to keep straight   I am looking foreward to seeing yours
Hawkeye

I work 2 or 3 days a week for a fencing contractor and we use one of these



http://protechmachinery.co.uk/ima...ractorRearMounted/P200sTele_1.jpg  
we must have knocked 1000,s of posts in with it , but we have had to make a reinforced plate that sits on to of the post
Slipster

Hawkeye wrote:
I work 2 or 3 days a week for a fencing contractor and we use one of these



http://protechmachinery.co.uk/ima...ractorRearMounted/P200sTele_1.jpg  
we must have knocked 1000,s of posts in with it , but we have had to make a reinforced plate that sits on to of the post


That's near as dammit the same as I have made    my only problem is that the down stroke is to slow      so now im going to to put the ram back as double acting and hope that I can force the ram down faster
Hawkeye

yes I would think it should work better , at the moment the weight is pushing the oil back  whereas double acting should force it back faster. good luck and pictures please
Slipster

Hawkeye    ive spent most of the day turning my single acting ram into a double acting ram and rerouting hydraulic pipes and fitting new valves        But the outcome is a fast acting ram  
Im just waiting for my new pulleys ive ordered and new cable .

Total cost £234      








   



Hawkeye

that looks like it will do the job,can you work it single handed from the tractor seat if you set the posts out first
Slipster

yes all the hydraulic controls are in the cab at the side of the seat.
Its got my mind working now as what I can make next  I ve got a couple of 80mm rams with a 250mm stroke. Ive already got a log splitter but was wondering about a log lifter for the front of the loader.
Pinpoint

Post knocker looking good....don't forget pics of it in action......a bit of video would be good to see how stable it is when every thing is in motion
Slipster

Well its been in full flow today puts 3 inch posts nooooo problems      

Never uploaded video before so Im just looking on how to do it
12Bore

 
sod

  Great to hear now await photos/video
Slipster

Hmmmm Have now decided to make the knocker so it will have side to side movement  
Pinpoint

Will it be push by hand along a slide and pin it...or maybe a threaded bar with Handel ....better for fine tuning.....or have you got spare services for the luxury of a double acting ram.

Just can't resist having a guess

Suppose if you are on some of the Lincolnshire flat lands keeping vertical is not much of a problem...or are you thinking???...maybe whilst I am at it
Hmmmmm  maybe.
Slipster

Im right on the edge of the Lincolnshire Wolds in fact the House at the top of our track is called Wolds End.
I have now finished the side tilt and used an old top link, it works really well. I have got a couple of rams but I ran out of hydraulics. If the weather stays fine my youngest and I are putting more posts in today so will try get some pics  
Slipster




Eldest


Youngest



Only thing left to do now is to fix something so that if the side angle adjuster comes out of the thread the knocker wont fall to one side and remove a finger or hand
Digindeep

looks a mean bit of kit...well done...
12Bore

 
sod

great job
cold comfort farm

post knocker

Hi All This is my first post on here as I am looking to build my own post knocker and came across this fab forum and slipsters design.

I bust my arm back in May and four operations later its not right so my hand post knocking days are now over.  I have a JCB telehandler and I only knock 3" post in soft (ish) ground so the post knockers you buy are too big for what I want.

Rather than start from scratch with a design I would like to copy a good design hence why I am here.  Cheeky I know but good designs are often copied.  
Slipster, would it be possible to send me a few close up pics with some tape measure pics as ref.   As for stopping the rotation how about a cowel over the top of the rotation shaft with a cut out onto the chassis so it can only tilt so far before it comes to a mechanical stop.  failing that a linger chain on the top link.

Merry Christmas all and hope your sheep are fat and in lamb.
Stephen
sod

Hi and    glad you found us, sorry to hear about your arm it will take a bit of getting used to doing thing another way

Hope you had a good Christmas and a great new year
cold comfort farm

Post knocker

Thanks Sod.

Had a tad of tinkerin time tonight and came up with this idea.  Basically its the same only using a longer stroke ram instead of the arm.  I have the ram spare so it seems a shame not to use it.

My concern would be can I move the oil fast enough (its double acting).  The ram is currently connected to my MF 135 so I think if i face the 135 in front of the telehandler I can (very roughly) simulate the action.  Has anyone else got any concerns, notes to add.  sorry about the poor pic I hope you can make it out.

Click to see full size image
Slipster

Hi ... only just seen your post... I know I shouldn't laugh but im in exactly the same boat hence the post knocker. Two years and numerous operations and bone grafts on my smashed up left arm like you my post knocking days are over (thank goodness). My ram is quite small and a fairly short stroke, the steel rope at the top is doubled round two pulleys making even more pulling length, Basically out of six inch of ram travel I have ended up with approx. three feet of weight drop and the ram handles it real easy. As soon as the rain stops I will go out with tape and take some close up pics. Ive just taken the hydraulic pipes off because im using them on my log grab that im adapting to my tractor. (pics to follow)  Kevin
cold comfort farm

Thanks Kevin  
Slipster

A few pics.  Im not sure what your fitting yours to but I didn't need much weight travel because as the post is knocked in I can lower the whole knocker on the loader the adjust the angle to suit. One thing im glad I did do was to fit the side angle its amazing how much the land slopes from vertical when to the eye it looks ok.




Height of the "T" Section is 1.5 mts   100 x 100mm




Length from Top of Arm to pin centre on ram approx. 800mm



Ram length approx. 300mm



The block I welded up some 30 x 50mm flat bar that I had and then filld it with old lumps of scrap steel I had  then to finish it off I sat it on the floor and filled it with a 1 to 1 mix of sand and cement, it weighs about 60kg.
I fixed it oneside so it would slide up and dow the T section but bolted the other side so I could remove it if required.
Its a bit rough and ready as I did make it from a lot of old steel I had in the Tardis garage but it certainly does the job    Oh I have fitted a piece of bar to stop the turnbuckle link from unscrewing all the way
Hope it helps  
Slipster

Re: Post knocker

cold comfort farm wrote:
Thanks Sod.

Had a tad of tinkerin time tonight and came up with this idea.  Basically its the same only using a longer stroke ram instead of the arm.  I have the ram spare so it seems a shame not to use it.

My concern would be can I move the oil fast enough (its double acting).  The ram is currently connected to my MF 135 so I think if i face the 135 in front of the telehandler I can (very roughly) simulate the action.  Has anyone else got any concerns, notes to add.  sorry about the poor pic I hope you can make it out.

Click to see full size image


If you do away with the arm and use your doble acting ram the I think you would have to use a double pulley, this way you would get more height from the ram stroke.
cold comfort farm

Telehandler

Many thanks for your pics.  I am fitting it to the telehandler for the same reason that I dont need a huge mast.  most of our land is on slight slopes so I will do the same.  
My thinking on the weight of the weight is I can knock them in my hand so anything heavier than the hand post knocker and make it drop at a similar weight ...should be OK.  
how much drop do you tend to get with the weight and do you get much bounce on the tractor.

regards
Stephen
Slipster

The loader is very stable
http://overthegate.myfreeforum.org/about28028.html

I suppose I drop the weight approx. 500mm each time when we knocked posts in by hand we averaged 20 blows to put one 75mm post in 400mm but that was into good soil, around here its mainly chalk and we can only knock in 300mm by hand, the post knocker does it into clay in 6 drops and chalk approx. 12 drops    I would say don't scrimp on the weight  

The tractor does not bounce at all as the force goes straight down
cold comfort farm

guides

on the pully do you have a guide to stop the rope popping off when it goes slack and bounces a bit.
Slipster



cold comfort farm

gimble

One more daft question.  how have you attached the mast to the stock on the rotating gimble.  what size did you use.

Happy new year.
Slipster

Re: gimble

cold comfort farm wrote:
One more daft question.  how have you attached the mast to the stock on the rotating gimble.  what size did you use.

Happy new year.












I attached mine using a 40mm pin welded onto the back of a quickhitch. One thing I will have to do is weld on some sacrificial wear plates to the inside. Hope it helps
cold comfort farm

Thank you

Thats Brill All i need now is some better weather to finish my bucket off and I can crack on with this project.

Many Many thanks, you have saved me hours of head scratching.
Slipster

you're very  

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