Adapting A Skidsteer Backhoe

[Gus Osmium]

Hi BFreaky,
I hope you feel great when you are using your backhoe. Inspirational project, thanks for sharing.

I have just bought a backhoe attachment, ex-Australian army, never used and stored inside in a machinery warehouse for 10 years. But it's configured for mounting on a skid steer and I need to fit it to the rear of my 65hp tractor. So I have to fabricate a subframe for a rigid connection to my chassis.

If I am reading your earliest posts correctly, you made your subframe from 15mm mild steel with M16 high tensile bolts? Is that correct? Was this adequate? If you were starting over, knowing what you know now - how would you do it?

i've added some pics below, any advice you can offer is greatly appreciated,
Thanks, Gus

 

[Renze]

Re: Tractor backhoe - homemade

I have just bought a backhoe attachment, ex-Australian army, never used and stored inside in a machinery warehouse for 10 years. But it's configured for mounting on a skid steer and I need to fit it to the rear of my 65hp tractor. So I have to fabricate a subframe for a rigid connection to my chassis.

I did quite the same thing: Converting a Bobcat 905B skidsteer mount backhoe to a tractor. Your backhoe is two sizes smaller than Bfreaky's, and mine is two sizes smaller than yours. I run it on a Zetor 3011, weighing 1500kg or so. The digging force is comparable to an 800-1000kg mini excavator. I estimate yours to be the strength of a 1500-1800kg mini excavator, (?????) but you use a much heavier tractor.

What i did, was making attachment points for the lower link arms, and instead of a toplink, mount a triangle to the tractors top link bracket, as if you have 4 point attachment to the hoe, to three points on the tractor. It prevents the hoe from tilting. Yours also has hydraulic outriggers, so if you had a triangle to the toplink bracket, and some chains that limit the lift depth of the hoe in the 3pt, by hooking these chains from the lower lift arm attachment points on the hoe, to the top link attachment point on the tractor, you can lift the rear end of the tractor with the outriggers, giving you a firm stand.

Even for my 3011 i wouldnt take the hassle of making a subframe when mounting a backhoe the size of yours, and use the above described method.
Because my backhoe doesnt have hydraulic outriggers, i think of putting a hydraulic cylinder under the A frame, to push the backhoe firmly on its legs because i get a sore crotch when manoeuvering myself into the insane position to operate the backhoe and keeping my left foot on the brake at the same time...

 

[Gus Osmium]

Re: Tractor backhoe - homemade

Hi Renze,
Thanks for your reply and for all your contributions on this thread, very educational for me.

I've just been to the supplier of my tractor this morning, they had a backhoe mounted on an equivalent tractor to mine just about to deliver to a customer (almost $10k for a chinese built backhoe attachment here in Australia, mine was $2.5k and is in really good nick). A couple of pics of their "factory" mounting of the RED backhoe attachment below. It has a single rigid top link attachment, you are recommending a triangular top link attachment for 4 point connection to the backhoe - I get that.

But the two diagonal stays shown on the factory backhoe attachment - do they provide a similar benefit the the chains you are referring to from the lower lift arm attachment points on the hoe to the top link attachment point on the tractor?

The pics of the underside are of my own yellow tractor, showing the subframe for the FEL bolting onto the front of the rear axle mount (the lower 3PL mounts are pinned to the rear of these axle mounts). I was figuring on extending the rigid subframe to the rear of the tractor. You think that is overkill? I've never had a backhoe attachment before and obviously need a bit of hand holding and a reassuring cup of tea.

Thanks, Gus

 

[duke7595]

Re: Tractor backhoe - homemade

Thanks. It's all mechanical, without electromagnetic valves

BFreaky You must be very busy with the project you are working on, however, "Gus" has been trying to get your attention for a little help with his BH build. Remember,
we all are in this lifetime together and need each others help now and again. Appears you are coming along nicely from the video you posted..

 

[Gus Osmium]

Re: Tractor backhoe - homemade

Thanks Duke,
The last thing I want to do is disrupt anyone's project. Can you believe he made his own buckets! I found this thread jaw droppingly inspirational.

Thanks, Gus

 

[farm boy00]

You guys. Give him a chance. He might only log on Every few day

 

[farm boy00]

You guys. Give him a chance. He might only log on Every few days

 

[Renze]

Re: Tractor backhoe - homemade

Hi Renze,
It has a single rigid top link attachment, you are recommending a triangular top link attachment for 4 point connection to the backhoe - I get that.

But the two diagonal stays shown on the factory backhoe attachment - do they provide a similar benefit the the chains you are referring to from the lower lift arm attachment points on the hoe to the top link attachment point on the tractor?

Yes, my solution was made as i went, so if i was to add hydraulic outriggers to my existing setup, i would have added two chains to be able to put the tractor weight on the outriggers. What you show in your pictures does exactly the same thing, it makes for a rigid connection between tractor and backhoe that doesnt bend sideways, and prevents the top links from going up when you push down the outriggers, but takes the tractor up with it.

Bfreaky's backhoe is a beast, most likely able to lift his entire 4.5 ton of Belarus tractor off all four wheels. You and i are using quite different tractor to backhoe ratios, so for the backhoe you showed in your pics, on a 65hp tractor i wouldnt take the hassle of a full subframe.

With front loaders, a subframe is more important because of off center pushing will put a lateral force in the transaxle. All a backhoe can do is pick your front end up, where it is strained in similar fashion as when you wheelie it during heavy draft work, so with a backhoe you bend it over the strong side of the transaxle and with a loader you bend it sideways, which is the weak side.

 

[Gus Osmium]

Re: Tractor backhoe - homemade

Thanks Renze,
That's a really clear explanation.
My tractor operating weight: 3,050kg (with ballast in tyres) + 925 kg FEL loader and bucket.
Do you have a suggestion for the thickness/class of steel I should be using?

 

[farm boy00]

Thanks Renze,
That's a really clear explanation.
Do you have a suggestion for the thickness/class of steel I should be using?

You really should post a be thread about this