50 Hp Articulating 128 Drawings

[fourinchdragslicks]

without being familar with your engine...how do you plan to limit it to 3500 rpm? the 3600rpm issue has been solved already, parts number and all ( http://cubfaq.com/davek.html ). but I would argue that cvs are the way to go. unless i missed it, you are sill using 2 manual transmissions right? By Synchronizing, are you refering to making sure that you have everything in the same gear? there was a guy who actually switched his articulated cub from hydro to gear ( http://www.cubcadetman.com/content/i...vids&Itemid=65 ) designing your transfer case may be the trickiest (most costly) part. so far as chains capable of the rpm, maybe consider a timing chain, but I dont know how many chaings that you may need to stack to transmit your torque. a direct gear transfer case is likely your easiest option, that will be the most failure resistant (choose gears and bearings wisely, since they are not all rated for the speeds and loads described here.

[cadetbemo]

RPM would be manually regulated i.e. foot/ hand control.
A VW 1.6 liter engine top rpm is about 4,000.
For hyd pump reasons I will try not to run it above 3,500.

I may go with cvs joints as they seem to be a more forgiving option.
I have seen some threads with an updated "Artie" machine. I had thought of contacting him about his creation. One of my biggest concerns continues to be the Transfer Case as you mentioned. I have considered using chains and gears out of a snowmobile as they can handle 150 hp and gear down a 9,000 rpm engine. I think that a #60 double roller would hold, off road guys use them for custom transfer cases in their pickups. Engine overhang weight is another large concern of mine.

I am shying away from a twin transmission design. Leaning toward a single 128 trans w/ Hyd assist. Running a smaller front axle would allow me to place it under engine better, reducing or eliminating engine overhang.

I have a couple drawings that I am going to share yet. I think that of my three final plans they are all viable. In the end it becomes a matter of personal preference and budget.

[cadetbemo]

Here is my rendition of what an articulating tractor my look like with transmission mounted to engine and a gear reducing transfer case mounted to transmission.

For the purpose of these diagrams I've removed most of gears in transmission leaving only 3rd gear and permanently locking it into gear. The gear reduction has been removed and transmission is being driven directly through input shaft.

A GM third member front axle would be used as front drive.

The most difficult part of this build would be either modifying a transmission to work outside of it's intended transaxle role or to find a transmission small enough that is intended for standalone use. I have yet to find a suitable transmission.

I share this drawing because I believe that there is some real potential for a design of this nature. I'm not sure I have the funds for the machining that I would like to do.

[cadetbemo]

Here is the complete picture of this design
I believe that the front axle could be moved forward more to reduce overhang.

[Sam Mac]

Looks like it's going to get expensive and complicated.

[cadetbemo]

This one I like, except for locking third gear. I would probably use a hydro rear.
I probably won't be doing one like this. I thought that I would share this drawing to help others with ideas they may have.
I have a drawing that I will be sharing shortly. After conversations with the great members of this site I've had to change my original plan. Although it may be buildable, I question it's everyday reliability with two transmissions that need to be synchronized.

After looking over this and other sites and seeing others who have a lot of questions and ideas, I thought it would be good to give others some ideas and drawings to help spur imagination. I really want a full-time 4wd machine but there are some pretty big hurdles to try and get over on a tractor this small.

[garnold]

Really interesting stuff. I'll have to start following this thread to learn how things progress.

[J-Mech]

Originally Posted by cadetbemo

I really want a full-time 4wd machine but there are some pretty big hurdles to try and get over on a tractor this small.

I think this is only true as a gear drive machine. There have been many done with hydro's. It is much simpler. Just sayin.

[sawdustdad]

J-Mech,
I know you are quite familiar with the hydrostats and how they operate. (I ready your FAQ, very well written, BTW.).

Regarding the dual hydro 4WD idea. could one pump drive both motors? Is there a way to take the output of one of the hydro internal pumps and run fluid to both internal motors (for a pair of hydrostatic axles) By tapping into the hydro front cover?

Or if you can't do that, how do you solve the swashplate positioning for a pair of hydrostats so the two axles stay close to sync'd.?

[J-Mech]

Originally Posted by sawdustdad

J-Mech,
I know you are quite familiar with the hydrostats and how they operate. (I ready your FAQ, very well written, BTW.).

Regarding the dual hydro 4WD idea. could one pump drive both motors? Is there a way to take the output of one of the hydro internal pumps and run fluid to both internal motors (for a pair of hydrostatic axles) By tapping into the hydro front cover?

Or if you can't do that, how do you solve the swashplate positioning for a pair of hydrostats so the two axles stay close to sync'd.?

That's a really good question. But, no, not with the sunstrand unit. The pump wouldn't be large enough to drive both motors, and there is no way to plumb it up. You can sync both the swashplates together with adjustable linkage, but it takes work. Best example I can provide is on extrememotorworks page. If you go to the home page, there is a pic of a articulated 1650 Aarons dad built. It is by far one of the best done articulated ones I have seen. It doesn't give any details on the build, but I have seen it and it's very well done.

I can't draw on the computer so I will try to explain. You basically just tie the two hydro's together with linkage, preferably directly without the spring swashplate, (the part that wears out all the time) and then put the cushioning spring on the linkage that ties to the handle. In other words, one cushioning spring for both hydros, so the stay synced. Honestly, the hard part is the linkage going though the pivot. I hope that made sense.

Thanks for the compliment on the write up!