Identify and explain this gearbox?

[Snoopy11 5,714]

12 hours ago, 8ntruck said:

Ok.  Now that I havedownloaded the pdf and looked at page 2, we now know the torque ratings:

 

Normal operating torque - 12.9 ft lb.  This is the maximum recommended normal operating torque.

Max. Acceleration torque - 15.3 ft lb.  This is the maximum recommended normal startup or shutdown torque.

 

Max. E-Stop torque - 44.1 ft lb.  This is the maximum salm on the brakes, stop it as quick as you can torque.  The gearbox is designed to survive 1000 applications of this amount of torque.  This is not the failure torque.  It will support more torque, but for fewer applications.

 

So, can you make 44 ft lb of torque with that big steering wheel?  Yup.  How often are you going to do it?  When reaching the steering stops?  When trying to turn the wheel when one of the front wheels is blocked by a log or a rare boulder on your property?  How hard do you have to hit something with a front wheel to back feed that amount of torque to the steering wheel?  This depends on the steering linkage geometry.

 

My gut reaction after seeing the torque specs for the gearbox is that it would work, but is open to durability issues.  It probably be OK for a tractor being used mainly on smooth, level ground,  which from what I've seen from your pictures, ain't what you will be doing.

 

AHA!

 

So... my work was not in vain!!!

 

Wonderful!!!

 

@ebinmaine... you may fill this out...

 

 

Don

[ebinmaine 67,257]

7 hours ago, sjoemie himself said:

with 8 to 10 turns from left to right

I meant to ask earlier and forgot...

How do you arrive at the figure of 8 to 10?

 

I'm thinking it'll be more like 3. 

I'm completely removing the OE Wheelhorse gears.  

Just wondering if missing something.   

[sjoemie himself 3,068]

On 1/27/2022 at 10:26 AM, ebinmaine said:

IIFF I use this gearbox I  should end up 8 to 10 total turns lock to lock

 

This is were I came up with that number 😉

Edited January 30, 2022 by sjoemie himself

[ebinmaine 67,257]

Just now, sjoemie himself said:

 

This is where I came up with that number 

Ahh. I shall correct that if possible.  

 

[ebinmaine 67,257]

@sjoemie himself

 

Thanks for catching that. I fixed it.  

 

 

[sjoemie himself 3,068]

Another thing you could maybe use is a steering rack out of a small car. Most racks have the option of tightening up the play that may develop over time.

Edited January 30, 2022 by sjoemie himself
Typo, thanks to lovely auto-correct

[ebinmaine 67,257]

Here's what I was thinking:

 

 

 

Looks like it's going about 60⁰ or so, 1/6 of a turn. 

 

So I should end up with less than 2 steering wheel turns, lock-to-lock. 

 

Edit to Fix silliness!!

Edited January 30, 2022 by ebinmaine

[ebinmaine 67,257]

5 minutes ago, sjoemie himself said:

Another thing you could maybe use is a steering rack out of a small car. Most racks have the option of tightening up the play that may develop over time.

I like the rack n pinion gear idea but I've already got the forward end of the steering system done.   

 

 

[sjoemie himself 3,068]

4 minutes ago, ebinmaine said:

I like the rack n pinion gear idea but I've already got the forward end of the steering system done

Check!

 

On the angels you've got me stumped.. 60° is 1/6th of a turn in my book? 360/60 right?

 

[ebinmaine 67,257]

1 hour ago, sjoemie himself said:

Check!

 

On the angels you've got me stumped.. 60° is 1/6th of a turn in my book? 360/60 right?

 

And THAT'S why I post these things.  

I fixed that too!

[Snoopy11 5,714]

1 hour ago, sjoemie himself said:

 60° is 1/6th of a turn in my book? 360/60 right?

 

 

I am getting dizzy...

 

 

Don

Edited January 30, 2022 by Snoopy11

[ebinmaine 67,257]

On 1/30/2022 at 7:25 AM, ebinmaine said:

@8ntruck

Thank you for taking the time to read the specs and "translate" them for me.  

 

Thought provoking for sure. 

 

When speaking of the torque ratings is that to say that if the output shaft were held still the input shaft could be subjected to the above listed numbers?

Or is it a moving rotation torque which I understand is very different. 

 

I'm trying to process to myself how many times I've experienced a torque rating of (say 44 ft-lbs) while driving in the rough terrain. 

To that end we've been smoothing the paths, eliminating rocks as we find them, don't put new paths over rougher areas etc. 

 

The steering geometry was carefully calculated (to the best of my very limited understanding) to reduce the strain in what will be a heavy machine. 

I chose tri rib tires to ease twisting motion effort. 

I had the spindles made with a pretty fair tilt of the tires to the top/outside which I've read benefits steering ease and steering traction on 2WD tractors. 

 

Still not sure which way I'll go yet but excellent food for thought.  

 

 

 

@8ntruck

When you get a chance can you peruse and define this post for me?

I'm wondering what the torque rating means and if the 40+ ft lbs is on the small side or large side...

 

[8ntruck 6,991]

@ebinmaine  those torque ratings are for the output side of the gear box.  This means that the input torque (force at the steering wheel) will be lower than the output torque by the gear box ratio to produce that amount of output torque.

 

Static torque and running torque act about the same on the system.  Static analysis is sufficent for these load cases.

 

Shock torque, such as a sudden stopping of rotation is like an impact load (think hammer strike) on the rotating system.  Actual loads on the system from shock torque depend on the dynamics of the system.  Factors here are many - geometry of the moving pieces, material properties of the components, rotational speeds, etc, etc.  For a steering system on a garden tractor, a dynamic analysis would probably be overkill.  

 

The gear box is rated at a maximum emergency stop output torque of 44 ftlb.  It is designed to stand up to 1000 applications of this load.  It will probably withstand more than 1000 applications, but operation at this load level will produce a failure sooner rather than later.  If I remember correctly, this is a 10:1 box.  That means the input torque at the steering wheel only needs to be 4.4 ftlb.  Real easy to do with your giant steering wheel.  Under 'normal' steering effort, I don't think you will be near 4.4 ftlb at the wheel - until you reach a steering stop.

 

I will assume that this gear box will go between the fan gear and the steering wheel.  This is good, as the fan gear is also a reduction gear - it will reduce the amount of torque that gets fed back to the steering wheel from impact loading at the front wheels.  On the other side of this coin is the fact that a relatively minor effort at the steering wheel will exceed the maximum output torque in the event a front wheel gets jammed against a log or something while you are trying to turn it.

 

On smooth, level ground with an operator who won't crank the wheel into the stops with maximum effort, it will probably do.  My gut reaction still is you will need something stronger.

 

Hope this helps.  Keep asking questions, I'll keep trying to answer them.

[ebinmaine 67,257]

7 hours ago, 8ntruck said:

Hope this helps.  Keep asking questions, I'll keep trying to answer them.

Absolutely. 

Exactly the information I'm looking to confirm. 

Thank you. 

 

7 hours ago, 8ntruck said:

those torque ratings are for the output side of the gear box.  This means that the input torque (force at the steering wheel) will be lower than the output torque by the gear box ratio to produce that amount of output torque

^^^^^^^^  This is what I was figuring on....

 

 

7 hours ago, 8ntruck said:

If I remember correctly, this is a 10:1 box.  That means the input torque at the steering wheel only needs to be 4.4 ftlb

.... And this ^^^^^  is what I was hoping you would not confirm. 

 

7 hours ago, 8ntruck said:

I will assume that this gear box will go between the fan gear and the steering wheel

So here's the thing...

I don't want to ADD this reducer. 

I want to replace the entire existing gear set.  

 

To really be exactly what I was thinking about it would need to be more in the 12:1 or 15:1 range but I could live with 10.  

 

But .. obviously... The gears or box I use would need to be substantially more heavy duty.  

 

 

Thanks again for your help.  

 

[wallfish 16,981]

42 minutes ago, ebinmaine said:

The gears or box I use would need to be substantially more heavy duty.  

Which the trade off may be the size.

There was talk of an auger gearbox if I recall correctly. Here's an old chainsaw attachment auger box and it's 12:1. Have had this thing for a while and was planning to use it for a future project steering set up too just as you are looking to do (but that's just another one in the Q which probably won't ever happen either).  I bought it for the purpose it's designed for but it's a different version that will spin backwards on the XL12 chainsaws so it doesn't work for the collection of XL12 stuff. Of coarse direction makes no difference for a steering application so let me know if you're interested. The drive shaft is 1/2" and that chainsaw pin to gear drive piece looks to be removable from the input shaft and the output shaft is 3/4". The offset shafts and larger size will create some engineering design challenges to fit compared to an inline box but that figuring it out stuff is half the fun of building.

[wallfish 16,981]

Just knda think'n out loud again for something to maybe set off a light bulb somewhere.

But what about absorbing the wheel shock forces since the box you have might work for everything else?

Like a heavy spring inline with the steering shaft. Pillow block bearings will hold the 2 shafts inline. The lighter steering forces to turn the wheels would still be achieved and the shock forces should be very temporary short duration so it may not effect the steering control so much but.

Basically the twisting of the spring will absorb the harder impact shock. There would probably be some trial error for the right size spring, attaching it to the shafts and testing. Attaching it would need to be very solid or it could end up like riding in a shopping cart. Doesn't work, the shaft can be welded back together

 

 

 

 

[Oldskool 6,640]

3 hours ago, wallfish said:

Which the trade off may be the size.

There was talk of an auger gearbox if I recall correctly. Here's an old chainsaw attachment auger box and it's 12:1. Have had this thing for a while and was planning to use it for a future project steering set up too just as you are looking to do (but that's just another one in the Q which probably won't ever happen either).  I bought it for the purpose it's designed for but it's a different version that will spin backwards on the XL12 chainsaws so it doesn't work for the collection of XL12 stuff. Of coarse direction makes no difference for a steering application so let me know if you're interested. The drive shaft is 1/2" and that chainsaw pin to gear drive piece looks to be removable from the input shaft and the output shaft is 3/4". The offset shafts and larger size will create some engineering design challenges to fit compared to an inline box but that figuring it out stuff is half the fun of building.

That's an interesting piece. I have never seen one of those before. 

 

I was wondering if the gear reduction from an old Briggs horizontal shaft or similar type engine might work.

[ebinmaine 67,257]

11 minutes ago, Oldskool said:

That's an interesting piece. I have never seen one of those before. 

 

I was wondering if the gear reduction from an old Briggs horizontal shaft or similar type engine might work.

Seems to me it would given proper construction technique. 

 

Found this too:

[8ntruck 6,991]

 Switch from a central shaft fan gear setup to a horizontal shaft out the side to a drag link setup - kind of a T bucket hot rod style of steering system?  That gear box has the geomerty that would allow such a system.  Gear box on top of the frame, steering shaft feeding directly into it.

 

Would something like that package well in the tractor?

[ebinmaine 67,257]

24 minutes ago, 8ntruck said:

 Switch from a central shaft fan gear setup to a horizontal shaft out the side to a drag link setup - kind of a T bucket hot rod style of steering system?  That gear box has the geomerty that would allow such a system.  Gear box on top of the frame, steering shaft feeding directly into it.

 

Would something like that package well in the tractor?

Ya might have something there.  

 

@Oldskool had sent me a video about a tractor that was all custom and used a (Cub?) Steering system with a drag link. 

Might be able to modify/combine the two.  

 

[wallfish 16,981]

 

43 minutes ago, ebinmaine said:

tractor that was all custom and used a (Cub?) Steering system with a drag link

Ross steering box?

https://www.ebay.com/itm/325018221123?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D236703%26meid%3D3b0d13990fad4fd98b4a1b2aa302eef5%26pid%3D101195%26rk%3D5%26rkt%3D12%26sd%3D115223295520%26itm%3D325018221123%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv9PairwiseWebMskuAspectsV202110NoVariantSeedWithWeightedSampleMeHot%26brand%3DCub+Cadet&_trksid=p2047675.c101195.m1851&amdata=cksum%3A3250182211233b0d13990fad4fd98b4a1b2aa302eef5|enc%3AAQAGAAACQDbZczR7M4rvzNxtXfnWSM18o4WZdUdaVpjg9DynC8Iv1QBN%2BoqkXsdTmseVCIyeNxwsPkCGJ1%2FZQTM5G6fAA%2BaLNYeoyeWVcebCESwu1SX2UM4PgirS3VK8lUZIYSaR9cZcTAkQgSKo4dEEE61Txlv3kMUxflsjo%2BnRPWW4%2Fxw5gMHCVrg%2BXj%2B%2BAezpQg9G5kDuH8j29ZWFdN%2Fx8S6I7AJgwBJqBA%2Fw6BfdxMwSKdGuQrF3Y33k5Q4hSFjNA27L7HkKKvb80IHl3Qa2EyqVaPOvsWoLhQ%2FTvbtNuzw5ufC38AA%2F6JxwY4RRmJo5P8EDnXLqBZwy8TWqBHOkPeqGUBfCWbrXbUa20CdUve5kAV54pHyXUY6PYEUNOuO9HekuY1yKi9e7fdD8QD8lVymPRojyopdCftFisX%2B%2F7zHlCvODd7MMg63ko5tnDFpn%2F2ulScnn2jcen9c6hCLhCwULiDjvKU6LEXWH9Z7nwD5DS8xVUlAxSCTvV%2B6Tx8GEsBGQ2%2Bjzif6GazB7bOTcswFyuQfl8I807CYTXMDMpzjh%2FeTAaB%2FFVePM7rptwu%2FTVv5GAURv0mqh7BOb1ia%2BtwIS0SS3dDIwyUib1UujpzkHudEOUck1GgVlV9B8GHfeyHps%2BG5xKBJ5nWtniFbbYMGxhodztksRt4Gf3g6oabJ4CNDsKnD%2F3FVMhXRLGafjctkHkRjUNh7NOI0Di5y%2FhO8aBFRmEMnoEHKSPm8jNS%2BjaiO7%2FboSDLhahCjWivPsR6tYfA%3D%3D|ampid%3APL_CLK|clp%3A2047675

[8ntruck 6,991]

@ebinmaine  take a look at your Furgeson's steering system.  Might find some inspiration there.

[Oldskool 6,640]

Reverse Corvair box?

[8ntruck 6,991]

@ebinmaine  Just some idle thoughts here.

 

Looks like you need ×/- 60 degrees on your normal fan gear type of steering system.  With proper drag link and driving lever design, you could set that 90 degree box up with the same +/- 60 degree of motion.

 

At 15:1, one turn of the steering wheel will give 24 degrees rotation of the output shaft.  With equal length links at the steering box and on the front spindle and assuming a +/- 60 degrees of rotation, this would be 5 turns lock to lock.  Make the link on the spindle 1/2 the length of the link on the box, you will get 2 1/2 turns lock to lock.

[ebinmaine 67,257]

11 minutes ago, 8ntruck said:

Just some idle thoughts here.

Excellent. 

Thank you.