Homemade Tiltrotator - How hard can it be ??

[Will_c]

Hi all,
I’m currently in my final year studying Agricultural Engineering at Harper Adams University, and for my honours project I’m looking to design and build a homemade tiltrotator to suit a Bobcat E27z excavator.

The machine is owned and used by my father for construction work and occasional landscaping. In the past we’ve had quotes from the major tiltrotator manufacturers, but the cost is difficult to justify — in most cases around a third of the machine’s value, which is hard to stomach when a 1-ton machine can be bought for similar money.

Current design thoughts​

My intention is to build the tiltrotator using:

• A standard-size slew ring
• Either tilt cylinders or a helical actuator for the tilt function
  (although helical actuators seem very difficult to source and prohibitively expensive)
• A second-hand hydraulic coupler for the hitch
• Plasma/laser cut parts welded together for the Frame

One area I’m currently struggling with is finding a suitable hydraulic rotary union that can pass through the centre of the slew ring to supply oil to a hydraulic quick coupler mounted underneath.

Design constraints​

Some of the main constraints I’m working with are:

• As low a build height as possible
• The excavator is fitted with a Geith hydraulic quick coupler
• The factory-fitted hydraulic thumb needs to be retained, as it’s extremely useful — removing the cylinder and hydraulics each time would be impractical
• Designed to be either direct-mounted or mounted under the coupler
• Six-pipe hydraulic design using the factory-fitted auxiliary lines
  (a diverter valve is fitted to the thumb so it can be switched over to the aux supply)

Keeping the thumb fitted makes the design more challenging, as a conventional tilt-cylinder layout is likely to clash unless carefully designed around it.

Rather than switching to an S-type coupler, I’m planning to retain the existing coupler style, as we already have multiple buckets and attachments to suit it.

What I’m looking for​

If anyone here has experience with:

• Designing or building a DIY tiltrotator
• Using slew drives / worm drives (IMO or equivalent)
• Sourcing compact rotary unions or alternative solutions

…I’d really appreciate any advice on what works well, what to avoid, and any lessons learned along the way.

Photos or videos of other home-built tiltrotators would also be great — I’ve only managed to find a handful of DIY examples online so far.

I have access to the university workshop facilities to build the attachment, although I intend to complete the majority of the work at home using fairly basic tools, as I’ve seen others do.

I will do my best to document the process of the build and post some photos and videos along the way

Thanks in advance — all input is welcome.

Cheers Will

 

[doobin]

@V8Druid
@CPS

Welcome mate. You are in the right place

One thing though- ditch the old buckets and hitch and go with S type. You would be spoiling the ship for a happorth of tar. Your first criterion on your list was ‘as low a build height as possible’ for Pete’s sake! Yes you will need more buckets- although you can also convert your own if you’re handy with a welder and gas axe.

I would go with an s type top hitch from @CPS. Lovely low build height and you will want to drop the tilty off as much as you use it in my experience.

Here’s mine showing the six pipe system for the hitch with a tap. Just look how low that s type build height is both top and bottom. I’d go s30, it’s plenty strong enough.

Oh, and a thumb will be an abortion with a tilty. It’ll work well with a normal bucket under your top hitch though. Hopefully it’s easily removable.

 

[JD450A]

Here monitoring for that word.

 

[V8Druid]

Here monitoring for that word.

won't need them Rory -- got two prop. Aux on the base unit

 

[Will_c]

@V8Druid
@CPS

Welcome mate. You are in the right place

One thing though- ditch the old buckets and hitch and go with S type. You would be spoiling the ship for a happorth of tar. Your first criterion on your list was ‘as low a build height as possible’ for Pete’s sake! Yes you will need more buckets- although you can also convert your own if you’re handy with a welder and gas axe.

I would go with an s type top hitch from @CPS. Lovely low build height and you will want to drop the tilty off as much as you use it in my experience.

Here’s mine showing the six pipe system for the hitch with a tap. Just look how low that s type build height is both top and bottom. I’d go s30, it’s plenty strong enough.

Oh, and a thumb will be an abortion with a tilty. It’ll work well with a normal bucket under your top hitch though. Hopefully it’s easily removable.


View attachment 78446

Hi, thanks for the reply.

Regarding the S30 -type hitch, I completely agree — the reduced build height is a big advantage and it’s definitely the best solution.

That said, because this is a cost-focused project, I’m planning (at least initially) to stick with a standard-style hitch. Mainly because I don’t want to start modifying/adapting our existing buckets and attachments at this stage. If the build goes successfully I will look into adding an s type bottom hitch.

Current CAD Design​

With my current CAD model I’ve achieved a total build height of : 345 mm, while still allowing ±36° of tilt. Using a standard hitch

 

[Storrsy]

won't need them Rory -- got two prop. Aux on the base unit

Well that was disappointing!

 

[Storrsy]

Oh, and a thumb will be an abortion with a tilty. It’ll work well with a normal bucket under your top hitch though. Hopefully it’s easily removable.

This is why I'm not keen on thumbs of that design. I know the yanks have them that way but actually the fully weld on ones are better, narrower stronger design and fully removable without taking off the hitch, plus you can get more in the "grab" when it's pivot is placed further up the stick. The ears that share the bucket pin on that one are a weakness for bending as I found out with my dads setup like that.

 

[JD450A]

Well that was disappointing!

Its only a matter of time.....

 

[DaveDCB]

Paint it brown

 

[V8Druid]

as far as I know I'm the only one here who's built one from scratch @Will_c ...

this'll give you a bit of a 'start point' with my build ....
it was fully documented on the old CEF (construction equipment forum) - before it died and this is a bit of a précis, on request from a few members here

Druidfab Variable Angle Rotator (VA-r) .. a bit of a project

this is gonna take some time ..... this is what I started with .... was a rotary FLT att. -- a carpet handling spike that the spike had snapped off of - I bought off my scrappy and created a rotary bar bender for 20mm bar that I had a BIG job for - several hundred staples for canal bank...

www.planttalk.co.uk

I didn't have the 'luxury' of multiple prop. aux.s to create a 6 piper with, so had to run it all off one prop. service, using my rotate pedal ...

finding suitable rotary couplings was also a serious dilemma ...
the Roemheld units I eventually sourced and used are the mutt's nuts and 90mm dia. (for ref.), plus I needed 4 galleries (2 for a hitch and 2 for an aux feed through the rotator)
if you're not planning on hanging a grab/clamshell under it a 2 gallery will do you -
I have a really nice 2 gallery off and Auramo rotary clamp set up (will have to find the pix), but from memory it's circa 50/55mm O/A dia....
the slew ring off it is also quite 'dinky' and I hung onto it as it would make a nice VA-r under a circa 3 ton machine.

biggest issue is sourcing a trunnion mounted ram, but have had a few ideas on that subject since 2014, when I started on mine.
it's 11 years old now, comes out/gets mounted, as I need it, but using it still makes me smile for its versatility

one thing I would say is DO NOT make your pick up pins fixed. the ability to direct mount it is invaluable and I often curse that I didn't do it ... may well alter that fact one day and put my Miller on 1/4" FF QC,s

my duck.....

lots of detailed pix here https://app.photobucket.com/bucket/...8a/album/db3d54ee-6782-4f2e-ba6e-b2cba004c8a1

 

[Vinpetrol]

as far as I know I'm the only one here who's built one from scratch @Will_c ...

this'll give you a bit of a 'start point' with my build ....
it was fully documented on the old CEF (construction equipment forum) - before it died and this is a bit of a précis, on request from a few members here

Druidfab Variable Angle Rotator (VA-r) .. a bit of a project

this is gonna take some time ..... this is what I started with .... was a rotary FLT att. -- a carpet handling spike that the spike had snapped off of - I bought off my scrappy and created a rotary bar bender for 20mm bar that I had a BIG job for - several hundred staples for canal bank...

www.planttalk.co.uk

I didn't have the 'luxury' of multiple prop. aux.s to create a 6 piper with, so had to run it all off one prop. service, using my rotate pedal ...

finding suitable rotary couplings was also a serious dilemma ...
the Roemheld units I eventually sourced and used are the mutt's nuts and 90mm dia. (for ref.), plus I needed 4 galleries (2 for a hitch and 2 for an aux feed through the rotator)
if you're not planning on hanging a grab/clamshell under it a 2 gallery will do you -
I have a really nice 2 gallery off and Auramo rotary clamp set up (will have to find the pix), but from memory it's circa 50/55mm O/A dia....
the slew ring off it is also quite 'dinky' and I hung onto it as it would make a nice VA-r under a circa 3 ton machine.

biggest issue is sourcing a trunnion mounted ram, but have had a few ideas on that subject since 2014, when I started on mine.
it's 11 years old now, comes out/gets mounted, as I need it, but using it still makes me smile for its versatility

one thing I would say is DO NOT make your pick up pins fixed. the ability to direct mount it is invaluable and I often curse that I didn't do it ... may well alter that fact one day and put my Miller on 1/4" FF QC,s

my duck.....
View attachment 78447


lots of detailed pix here https://app.photobucket.com/bucket/...8a/album/db3d54ee-6782-4f2e-ba6e-b2cba004c8a1

Still makes me smile !

 

[Will_c]

Hi @V8Druid

Wow — that is quite the build! A huge amount of work has clearly gone into it, and the end result is impressive.

As you mentioned, trunnion mounts do seem to be the preferred method for mounting the tilt cylinders. My current thinking is to purchase a hydraulic ram kit from Steerforth with a 200 mm stroke, then shorten the rod and outer by 30 mm to give a final stroke of 170 mm.
I’ve seen a few builds where people fabricate the trunnion and then weld it directly to the cylinder body, although I’m a bit wary of this approach due to the risk of distorting the cylinder tube or affecting seal life.

Regarding the rotary union you mentioned, my plan is initially just a 2-pass unit to supply the hydraulic coupler. Would you potentially be willing to part with it? If so, do you happen to have any photos or details of the unit?

Thanks for sharing your build — it’s been really helpful for reference.

Looks like I need a trip to the scrappy to pick up some materials

 

[Lancs Lad]

Welcome Will, what a great first thread

 

[V8Druid]

Hi @V8Druid

Wow — that is quite the build! A huge amount of work has clearly gone into it, and the end result is impressive.

As you mentioned, trunnion mounts do seem to be the preferred method for mounting the tilt cylinders. My current thinking is to purchase a hydraulic ram kit from Steerforth with a 200 mm stroke, then shorten the rod and outer by 30 mm to give a final stroke of 170 mm.
I’ve seen a few builds where people fabricate the trunnion and then weld it directly to the cylinder body, although I’m a bit wary of this approach due to the risk of distorting the cylinder tube or affecting seal life.

Regarding the rotary union you mentioned, my plan is initially just a 2-pass unit to supply the hydraulic coupler. Would you potentially be willing to part with it? If so, do you happen to have any photos or details of the unit?

Thanks for sharing your build — it’s been really helpful for reference.

Looks like I need a trip to the scrappy to pick up some materials

what do you propose to use for a slew ring?

 

[Will_c]

what do you propose to use for a slew ring?

Currently I am looking at 2 options / the smallest slew ring from approved hydraulics or an IMO 156 slew ring , When comparing both options the Imo is more compact so will probably be the better of the two.

 

[V8Druid]

don't get too hung up on going too small with the rotator ...
your hitch width, etc. will determine the width of your ultimate build and you're unlikely to have it on for deep narrow trenching anyway
your tilt ram is going to be outside the width of your hitch, by a significant amount ......
similarly don't get hung up on the drive motor's orientation
unless you go for a helical drive tilt ...
but as you rightly say they are eye wateringly expensive, even s/hand.
and there is always the debate over whether they drift too much?...
Liebherr's thoughts would indicate otherwise, ditto Kinshoffer with their NOX ..
have 'played' with Kins's HPX helical powered grab/clam units and they do not seem to lack in closing force or retention of grip.

Are you a Diesel Creek fan ...
Matt pulled a helical drive apart on his man lift a few episodes back and something similar could well be a possible source for a helical drive as you're not building for anything 'big' ... if you could find a scrapper ?

here's the strip down

and the re-assembly

's got me thinking now @Mogman ... you got anything in your toy store?

and on the subject of hitches .. they're all right on here - S type is by far the lowest build height (second only to B20 ) ...
nothing to stop you building an S type hitch to suit your own pin dimensions/width though assuming your buckets are ALL the same ..
have one drawn up (well sketched out) for myself to replace the Hill at some future date (when I get around to it)....
width for your proposed size would/could/may well be, be an issue though
could even go half hitch and negate the need for through hydraulics

 

[V8Druid]

Hi @V8Druid
Regarding the rotary union you mentioned, my plan is initially just a 2-pass unit to supply the hydraulic coupler. Would you potentially be willing to part with it? If so, do you happen to have any photos or details of the unit?

Thanks for sharing your build — it’s been really helpful for reference.

Looks like I need a trip to the scrappy to pick up some materials

here's the little rotary

... cute eh?
and this is where it came from

 

[V8Druid]

cheapest (and only) one on ebay currently - Roemheld rotary hydraulic coupling (they do do a 2 gallery, but even rarer than the 4 and six gallery are like hen's teeth - only seen one in last 5 years - sat on my bench currently - brand new )

Pardon our interruption...

my 6 gallery - needs a case drain though -- considered using it and ganging up four (2 x 2) of the galleries for a better flow to atts

absolute steal ......

 

[V8Druid]

cheapest (and only) one on ebay currently - Roemheld rotary hydraulic coupling (they do do a 2 gallery, but even rarer than the 4 and six gallery are like hen's teeth - only seen one in last 5 years - sat on my bench currently - brand new )

Pardon our interruption...

forgot to say, that's less than a third of new cost for one of those

 

[V8Druid]

searching for rotaries for you @Will_c , I just tripped over some ideal rams for creating an S type hitch, which's been a bit of a stumbling block for creating one