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Light duty Jib crane

Thumper68

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May 16, 2013
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Duluth MN
I just spent most of the last 2 days standing in front of the Lathe making parts for a light duty Jib crane.

When I built the shop I had this in mind and now is the time to get on with it.

To start there is a full cubic yard of concrete with 8 5/8th's J bolts as a base under the slab, the J bolts were tied into the Rebar as well so that is covered.

I have been collecting materials for this build for about 2 years and as of a few weeks ago I sourced the last needed items.

The first job was to take a 18" length of 1018 3 1/2" round and make it into the pivot shaft, 5 inches remained 3 1/2" to weld into the post, the next 10.5" were turned down to 2" and the last 2.5" turned down to 1.5" and threaded for a 1.5-6 nut.

Once the pivot shaft was turned to size it was on to the UHMW bushings, since I don't have a boring bar that long I did it in 2 pieces, started with 2 6" pieces, Had to mount them in the 4 jaw chuck to bore the 2" hole through the center, once that was done I switched back to the 3 jaw to turn the outside, .75" remained at the 4" nominal and the rest was turned for a tight slip fit in the pivot tube.

Then I needed some washers, 3/8ths" thick 4" od, 2.050 Id, cut these out with the plasma and then mounted them in the 4 jaw and drilled and bored the center hole, once the center was done I switched back to the 3 jaw again so I could hold them from the center hole and turned the outside to 4".

I needed the washers done so I could get the final length for the Bushings, did a trial assembly and I needed to shorten the bushings by .250 each, so back onto the lathe they went and got sized.

While I was waiting for the pivot shaft to cool down for final turning I was able to get a few more things done.

Marked out the 1/2" base plate for the hole pattern.
Cut the 16 gussets.
Cut the I-beam to length and notched it to match the pivot tube, I thought about mounting it in the mill and using a fly cutter to cut the radius but in the end just marked it out and cut it with the plasma cutter and touched it up with the angle grinder.
Cut the 1/4" tube to beam gussets.

Tomorrow I should be able to finish up all the prep before I head into to town for a Dr's appt.

For anyone who is wondering I spec'd this out for 1/2 ton but will probably never exceed 500 pounds since it's main purpose is to lift things onto the mill and lathe.

Friday should be welding day!!
 
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Kaizen

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Jan 9, 2015
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New England
Can't wait for the pics. I made one using a winch. Not so much a crane but just a moving jib pole


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Bib Overalls

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Dec 4, 2006
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3,318
Location
Jonesboro, Arkansas
I'd like to see some pictures as well. My friend Barry has a jib crane in front of his shop. The winch uses compressed air. I used it for the first time to unload some heavy hydraulic cylinders from my truck. Nothing like having the right tool for the job.
 

zkdiesel

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Oct 6, 2013
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chicagoland cornfields
Love my jib crane, gets used very frequently. Have 12' height under the beam and about 11' reach. Have 1 ton electric hoist in it
Crane was free, have about $400 in concrete and anchors and 200 in hoist. Was very worth it
Also have a telescoping boom I built for the skid steer with winch on it for outdoor booming activities
 
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Thumper68

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May 16, 2013
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Duluth MN
Love my jib crane, gets used very frequently. Have 12' height under the beam and about 11' reach. Have 1 ton electric hoist in it
Crane was free, have about $400 in concrete and anchors and 200 in hoist. Was very worth it
Also have a telescoping boom I built for the skid steer with winch on it for outdoor booming activities


I would love to have one that size, this one will have around 8 feet under the boom with a 8 foot reach.

The pics as promised.

Pivot pin on the lathe.
View media item 73936
Pivot pin, BTW I am not good at single pointing a thread up to a shoulder on the lathe yet, so I did it about half way and then used a die to finish it, turning a 1 1/2-6 die is a lot of work, 24 inch adjustable wrench with a cheater on it got the job done.

Notice the improvised chip deflector.
View media item 73940
UHMW bushings, that was a blast, finally got the speed, feed and depth of cut just right so that the chips just peeled off and fell to the bed, before that I had chips, strings and fluff flying everywhere.
View media item 73939
4 inch dia. 3/8ths thick washer, plasma cut the blank and drilled and bored the center hole, turned the OD. to final dimension, and faced both sides.
Oh the nut is here too.
View media item 73938
All assembled, just need to turn the pivot tube to length.

View media item 73937
 

waynem

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Joined
Apr 3, 2006
Messages
15
On something like this I would use a 12 pitch thread. A lot easier to thread. Less material removal and the carriage is traveling at 1/2 the speed of 6 pitch towards the shoulder. Nuts are easily purchased. Nice work.
 
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Thumper68

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Duluth MN
On something like this I would use a 12 pitch thread. A lot easier to thread. Less material removal and the carriage is traveling at 1/2 the speed of 6 pitch towards the shoulder. Nuts are easily purchased. Nice work.

I agree, but I had the nut and my local supplier did not have a 12 pitch in stock, if they had it would have been bought. I also have a 1 1/2-12 die picked up in the same auction lot as the 1 1/2-6.
 
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zkdiesel

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Oct 6, 2013
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chicagoland cornfields
Mine. 7" diameter post that's 1/2" wall. This ones smallest of 3 Jin cranes with all others having larger mast
 

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Thumper68

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Think the schedule 49 is going to be the weak link, like very weak compared to rest.... maybe some bigger dom thick wall?

Mine. 7" diameter post that's 1/2" wall. This ones smallest of 3 Jin cranes with all others having larger mast

You are correct the sched 40 is the weak link, but it still should be plenty strong for my application. I have had my eye out for a nice piece of tube but after a couple of years looking have yet to find one and buying new is not in the budget for this build.
 

dr_clyde

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Holland, MI
Looks like a fun project. I'm considering making one of these myself. I probably would've used at least sch. 80 for the upright tube, however. But for 500 lbs or whatever it should be fine.

I'm sure you posted it somewhere, but what are the specs on your lathe?
 

sberry

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Brethren, Michigan
I did one for a Bud, the design is slightly different but didn't machine. Made it from stock pipe and greased it.
 

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Thumper68

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Looks like a fun project. I'm considering making one of these myself. I probably would've used at least sch. 80 for the upright tube, however. But for 500 lbs or whatever it should be fine.

I'm sure you posted it somewhere, but what are the specs on your lathe?

Its just a little Sheldon 10" Kinda small for the job but it got it done with light passes.

I did one for a Bud, the design is slightly different but didn't machine. Made it from stock pipe and greased it.

I had thought of doing it like that as well.
 
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Thumper68

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Finally had some time to get back on this today.

First up was finishing the base, got the base plate cut out to fit over the electric box, then I spent a bit of time leveling out the nuts, think parking lot light where the studs come out of the concrete and there is a nut and washer, then the base of the light pole and another nut on top. I got the final dimension for the first set of gussets/standoffs and got those cut to final length.

Then it was some grinding, each plate had to be prepped for welding with 4 chamfers leaving about a 3/16 land.

The finished part.
View media item 74089
While that was cooling I got to work on the post and pivot pin, I prepped the pin and then using some bits of mig wire I centered the pin in the pipe and tacked it into position.

Using a straight edge I confirmed that it was straight and made the top weld, I left about a quarter inch sticking out for a nice weld fillet.

View media item 74088
Then I moved it over to the mill and drilled 8 holes for plug welds, I waited to do it as a fixture so that I could also drill into the base of the pin about a 1/4 inch so that the plug welds also act as pins.

Then it was time to turn the heat up and go to town welding the plugs.

View media item 74087
That's it for tonight I should have some time tomorrow to finish this up at least the fabrication, might be a bit before I have some help to assemble it in place.
 
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Thumper68

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Well it's all welded up, taking a break for it to cool, should be a couple of hours then it is clean up and paint. My oldest son is coming on Thursday to help with the install, it has gotten heavy enough where it is not safe for me to do it myself.

I could really use a jib crane to set up this jib crane :lol:

I will have more pics tonight.
 
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Thumper68

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Put mine up by myself. Was sketch as can be as mast had to be assembled on floor, uprighted with skidsteer and somehow landed it

Yeah no skid steer handy and I don't want to grab it mid way with the engine hoist and try and up right it.

Honestly I still do not have a plan for how to do it, might bring a couple of sections of scaffolding in and use that to set it.
 
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Thumper68

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Well we got it set on Thursday, was way easier than I thought it would be, the funky base turned out to be the part that made things smooth, we put a 2 inch strap under the mid base and with a guy on either side they lifted it while I guided it in place, a bit of fussing with the nuts to plumb the post and we bolted it down, then we installed the beam, slick as snot other than the fact we had it in place and forgot the lower washer, so we had to lift it up and put the washer in.

First half of the build video.
 

C_F

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Utah...SNOW BLOWS!
Nice looking project! I imagine the nylon bushing will allow it to swing pretty easily with weight on it.

I love the video at the end, when you were drilling the holes in the base...zoom, zoom, zoom! Very entertaining. :D
 
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Thumper68

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Nice looking project! I imagine the nylon bushing will allow it to swing pretty easily with weight on it.

I love the video at the end, when you were drilling the holes in the base...zoom, zoom, zoom! Very entertaining. :D

Thanks, I have found that I prefer the video's where they use high speed to show most if not all the process in a shorter time frame for this kind of build, so that is what I did as well.
 
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