How to make the curve on a backhoe bucket?

[jim_wilson]

I'm contemplating welding up a backhoe bucket. I've got some use for a 24" or even a 30" bucket - and they are available out on the market - but they're darn expensive. It doesn't seem like a very complicated project - except for one thing: how to bend the steel that makes up the main part of the bucket.

making the "sides" , getting a cutting edge, making the mounting brackets - etc. - those are all pretty straightforward. But the "back" of the bucket typically is a semi - semi-circle shape.

I can see how this might get stamped out in a press - which I don't have. I can also see how this might be done in a plate-roller - but it would have to be a big one for the gauge of steel that typically gets used in a bucket. I'm wondering if there is some other way - or if maybe I just need to find a metal shop with a big plate roller and have them do it.

 

[BukitCase]

"I'm wondering if there is some other way - or if maybe I just need to find a metal shop with a big plate roller and have them do it."

That would be one way - or you might get lucky (as I did) and find a 4 foot "clean out" bucket for a mini-excavator on CL for $75. Mine had the tabs cut off (who cares in this case) and the guy was cleaning out stuff he didn't need any more. Lucky me.

My case 580 has a 2 footer and I built a 6" from C channel and 1/4 plate, but need a "toothless" 18" for foundation trenches. This will leave the rest of the "pre-curved" section for a 12" and a "toothed" 18 if I need them, all from the one 4' bucket.

If you're desperate you can do a "pseudo-curved" bucket by welding narrow strips together, each at a slight angle. Probably won't clean out quite as good, but there have been a couple of posts here in the last 6-8 months of guys doing just that.

You would cut out the sides, then use 1-1/2 or 2" flat bar cut to same length as your bucket width, tack everything in place, then back-stitch everything to keep warpage to a minimum.

HTH... Steve

 

[jim_wilson]

"I'm wondering if there is some other way - or if maybe I just need to find a metal shop with a big plate roller and have them do it."

That would be one way - or you might get lucky (as I did) and find a 4 foot "clean out" bucket for a mini-excavator on CL for $75. Mine had the tabs cut off (who cares in this case) and the guy was cleaning out stuff he didn't need any more. Lucky me.

My case 580 has a 2 footer and I built a 6" from C channel and 1/4 plate, but need a "toothless" 18" for foundation trenches. This will leave the rest of the "pre-curved" section for a 12" and a "toothed" 18 if I need them, all from the one 4' bucket.

If you're desperate you can do a "pseudo-curved" bucket by welding narrow strips together, each at a slight angle. Probably won't clean out quite as good, but there have been a couple of posts here in the last 6-8 months of guys doing just that.

You would cut out the sides, then use 1-1/2 or 2" flat bar cut to same length as your bucket width, tack everything in place, then back-stitch everything to keep warpage to a minimum.

HTH... Steve

I've thought about doing that - but all the excavator buckets I've found were always big money - to the point where I'd be better off just buying a new bucket.

I've been searching Craigslist for buckets - I know what the interchange is for my hoe (Kubota BH77) - but there just isn't that many out there.

 

[GLyford]

Depending on how thick you intend to make your shell, one way I've seen people describe it is to chain the bucket shell to a rigid frame or structure, with the shell welded onto the straight part of the sides leading up to the curved section. Bolt or weld an attachment to the free end, and start pulling it into the curve as much as you can with a come-along or chain tensioner, then weld. It might only be an inch or less at a time. You could help speed it up a little by heating the bend line, which would also help preheat your weld. Bend-weld-bend-weld and so on until done.

 

[jim_wilson]

Depending on how thick you intend to make your shell, one way I've seen people describe it is to chain the bucket shell to a rigid frame or structure, with the shell welded onto the straight part of the sides leading up to the curved section. Bolt or weld an attachment to the free end, and start pulling it into the curve as much as you can with a come-along or chain tensioner, then weld. It might only be an inch or less at a time. You could help speed it up a little by heating the bend line, which would also help preheat your weld. Bend-weld-bend-weld and so on until done.

Yeah - I was thinking of that too - I figure I could make "jig" of a sort - bolt the sides and one end of the main plate to the jig - then basically weld my way around until I've got it all held together.

 

[jmc]

Jim, when you said making the sides would be straightforward, I had a flashback to the bucket on my Case 480F. Without walking out there and checking it with a square, my recollection is that the sides are angled such that the bucket opening is wider than the bucket width deeper down into the bucket. It's classic cutter design where they build in a clearance angle so the body behind the actual cutting edge does not drag. It might be subtle or it might be my imagination.

 

[BukitCase]

Here's the more pertinent (I hope) threads out of 1449 results of a search of this forum on "backhoe bucket weld home made" - may be some "gems" somewhere, good reading for the next "rainy day"...

http://www.tractorbynet.com/forums/build-yourself/267513-diy-excavator-bucket.html

http://www.tractorbynet.com/forums/build-yourself/164970-12-backhoe-bucket-pics.html

http://www.tractorbynet.com/forums/build-yourself/233975-smaller-backhoe-bucket.html

http://www.tractorbynet.com/forums/build-yourself/111905-smaller-backhoe-bucket.html

http://www.tractorbynet.com/forums/build-yourself/65175-lets-talk-about-bh-buckets.html
(describes a bending method)

http://www.tractorbynet.com/forums/build-yourself/24676-built-me-bucket.html

http://www.tractorbynet.com/forums/build-yourself/267730-back-hoe-digger-bucket-theory.html

Rain's stopped, guess I better "GOMA" and do something useful... Steve

 

[mrmikey]

To save yourself a lot of grief and wasted time, find a welding/fab shop with a brake. Take them a template with your plate and ask them to brake it, shouldn't take more than 1/2 hour but you may get dinged more depending on the minimum, it'll be the best $100 you spent.....Mike

 

[Stimw]

I made this 6" bucket for my Hoe out of 3/16" steel.
I have a 1' press brake for my 50 ton Ironworker and I just bumped the curve until I got the profile I needed.
I made a pattern of the side of my regular bucket out of cardboard, chalked it on flat plate and cut it out with my Plasma Cutter.

As stated, a good fab shop can bend the back for you for a reasonable price.
They should have the metal plate too. A good shop will have "drops" from other jobs in their inventory so you don't have to buy a full sheet.

 

[Arc weld]

A lot of backhoe buckets use a compound curve. A steel supplier with a plate roller could maybe form it but a bending brake could make it just how you want. If it was a narrow strip you might be able to form it yourself but a wide piece like a bucket, get it formed. There's a reason new buckets aren't cheap but often you can find used ones pretty reasonable.

 

[Code54]

The local steel supplier here has some MASSIVE presses and rolls and told me they can bend any curve needed. I also recall it being really cheap - want to say something like $20 - just recalled thinking if I am building a bucket I will let them do the bend for that little bit of cash....

 

[Sfrankland]

So I read this post today and it got me thinking about building a ditching bucket for my backhoe. I had some scrap plate laying around and started cutting out the parts for my bucket. When I got to the point where I needed to bend the bottom of the bucket I tacked the sides to my welding table so the front edge was flush with the edge of the table. Then I used a ratchet strap to bend it around the sides. I would max out the strap make a few tacks and then reset the strap. Worked out perfect. Will start a build thread tomorrow when I get the camera charged up again.

Should add that the bucket is 24" wide and the bottom is 1/8" plate.



Heavy tacks holding it to the table.




And the ratchet strap doing its job. For the last few inches I had to cut a hole in the plate to prevent the hook from sliding off.

 

[PILOON]

When I made my snow plow blade I took the 1/8" X 60" X 16" 'plate' to a fab shop.
They made small bends every inch to form the blade shape that I wanted.
The press brake was about 8" long and could easily handle 1/4" stock full width.
The charge was a mere $25.00 !
And they did that as I watched saving me an additional trip to pick it up.
I know of 2 shops that do this sort of service within 20 miles either way. Both also stock all sorts of metals but neither have laser or other fancy cutting options, just massive sheers.

This to say that to form a bucket skin would be a piece of cake for most fab shops.

 

[Kernopelli]

When we made our last bucket, I used what was on hand. I planned to bend a short piece of 1/4" just as SFrankland described but it was just too short and I could not get it to make a smooth arc. I even welded some "leverage bars" to it but the end wouldn't come out smooth. I ended up cutting evenly spaced perpendicular lines about 1/8" deep and it actually made a nicer arc. Basically the same principle Piloon described ( multiple short, flat bends). I filled the cuts with weld beads and did some light grinding and it turned out nice.....almost like it's hard faced in fact.

 

[jim_wilson]

Jim, when you said making the sides would be straightforward, I had a flashback to the bucket on my Case 480F. Without walking out there and checking it with a square, my recollection is that the sides are angled such that the bucket opening is wider than the bucket width deeper down into the bucket. It's classic cutter design where they build in a clearance angle so the body behind the actual cutting edge does not drag. It might be subtle or it might be my imagination.

I've been looking at the bucket on the BH77 - and that is exactly how the factory one is made. The sides have an angle on them so that the "rear" of the bucket is narrower than the opening.

This makes sense - you want dirt to fall out of the bucket. Looking at the thing - it actually looks pretty straightforward to produce a bucket *if* - I can find a way to make that curved piece. All the rest of it is pretty straightforward stuff. I just have to find a source for a cutting edge - which I'm going to assume should be made out of something like AR-400 - then find a source for the two side cutting edges - which again I'm going to assume should be made out of something like AR-400 - and then get the mounting ears and the sides cut - and weld the whole thing together.

That curved piece is really the biggest technical hurdle from what I can see - but at least it has what looks to be a relatively simple curve - so it might be something that could be turned out by somebody with a plate roller. As I get the time I'm going to see if there's anyplace locally that might be able to do this. The rest of it I'm sure I could get produced if I just find somebody who can cut the parts.

 

[jim_wilson]

Here's the more pertinent (I hope) threads out of 1449 results of a search of this forum on "backhoe bucket weld home made" - may be some "gems" somewhere, good reading for the next "rainy day"...

http://www.tractorbynet.com/forums/build-yourself/267513-diy-excavator-bucket.html

http://www.tractorbynet.com/forums/build-yourself/164970-12-backhoe-bucket-pics.html

http://www.tractorbynet.com/forums/build-yourself/233975-smaller-backhoe-bucket.html

http://www.tractorbynet.com/forums/build-yourself/111905-smaller-backhoe-bucket.html

http://www.tractorbynet.com/forums/build-yourself/65175-lets-talk-about-bh-buckets.html
(describes a bending method)

http://www.tractorbynet.com/forums/build-yourself/24676-built-me-bucket.html

http://www.tractorbynet.com/forums/build-yourself/267730-back-hoe-digger-bucket-theory.html

Rain's stopped, guess I better "GOMA" and do something useful... Steve

:laughing:

Thanks for posting those links. One of those threads was one I actually posted in years ago with some pics of the 24" bucket I had on my old BX23.
http://www.tractorbynet.com/forums/build-yourself/65175-lets-talk-about-bh-buckets.html

I had totally forgotten about that. Reading thru it reminded me of some other questions about building buckets:

What materials would be the "right" ones to use when building it? Should the cutting edge be made out of something like AR-400 ? Should the bucket edges also be made out of AR-400? Build the rest of it out of mild steel - or should it be high strength steel?

That thread above that I posted in I made a comment that the 24" bucket I had on the BX23 - was showing serious wear on it's cutting edge and on the edges of the bucket sides. I don't remember seeing that kind of wear on the sides of the bucket that came on the BX23 - or on my BH77 bucket (might not have enough time on it yet to know yet though).

That leads me to believe that whomever built that 24" bucket I had on the BX23 - probably just used mild steel on everything.

 

[jmc]

I've been looking at the bucket on the BH77 - and that is exactly how the factory one is made. The sides have an angle on them so that the "rear" of the bucket is narrower than the opening.

This makes sense - you want dirt to fall out of the bucket. Looking at the thing - it actually looks pretty straightforward to produce a bucket *if* - I can find a way to make that curved piece.

Good. If yours is going to be like a factory bucket, then your flat blank is going to have to be hour glass shaped, or you're going to be doing some angle grinding after forming. Looking forward to seeing the result.

 

[Arc weld]

Don't know how to post a link but if you've got some heavy rolling you need done, check out the "Monster Rolls" at Edmonton Exchanger. The largest in N. America! Will roll 8" thick cold and 12" thick hot. They are serviced by a 100 ton overhead crane!:shocked: They also have an inhouse designed head press that's 3000 tons. It uses a 6' dia. hyd. cylinder. They have no shortage of work. I went to school with the foreman. He lucked out and got an apprenticeship offer after going there for work experience. Strangely enough, he bought one of my acreage lots 20+ years later when I subdivided and built a fancy house and garage. Why is it always the other guy who's in the right place at the right time???

 

[jim_wilson]

Good. If yours is going to be like a factory bucket, then your flat blank is going to have to be hour glass shaped, or you're going to be doing some angle grinding after forming. Looking forward to seeing the result.

I'd like to make this as close to a "factory" bucket as possible - so what's going on right now is I'm thinking this thru in my head as to how feasible it is. I'm also behind the curve a little since my MIG has died - and I sold my plasma cutter a couple of years ago - so I've got to go out and invest in some new equipment before I can really do any of this. I think I've got a plan of attack thought out - now I've just got to get going on it.

 

[Carl_NH]

Hi Jim,

Here's a 24" new Bradco bucket in VT at a decent price. Maybe some minor pin work, maybe none!

Price seems decent. 24" Bradco Backhoe Bucket