Open Source Ecology - User contributions [en]

The Only Production Steam Engine in the World

2010-04-27T01:50:28Z

Whitworthsocket:

The only company producing practical, small scale steam engines in the world that we know of is http://www.tinytechindia.com -

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[[Category:Steam Engine Construction Set]]

Also http://www.strathsteam.com/
A South Australian steam manufacturing company

LifeTrac

2010-03-14T05:18:11Z

Whitworthsocket: /* Bill of Materials for Industrial Counterparts */

{{site header}}
<center>
LifeTrac, the low cost multipurpose open source tractor.

[[Image:lifetrac_loader.jpg|thumb]]
[[Image:lifetrac_bend.jpg|thumb]]
[[Image:Backhoe.jpg]]

<eeehtml>
 

<object width="480" height="385"><param name="movie" value="http://www.youtube.com/p/28958DE807A18811?hl=en" /><embed src="http://www.youtube.com/p/28958DE807A18811?hl=en" type="application/x-shockwave-flash" width="480" height="385"></embed></object>

 
See corresponding <a href="http://openfarmtech.org/weblog/?p=480"> blog post</a>
</eeehtml>

</center>

=LifeTrac Concept=

OSTrac is an open source tractor/ loader. It is an articulated tractor that steers by bending in the middle. It also has a flexible coupling between the front and back, so that the wheels stay on the ground at all times.

It is based on [http://www.cadplans.com/cadtrac.htm CADTrac, a set of plans that you can buy]:

[[Image:CADTrac.jpg]]

But it is redesigned thoroughly by enlarging the size and making construction simpler.

==Goals==
*Lifetime design
*Scalable
*Modular
*Easy to maintain
==Features==

It has a number of features that set it apart from skid loaders and make these vehicles suitable for agriculture. The main features for agriculture are a 3-point hitch, power takeoff, and high-flow hydraulic takeoff. These features make the [[LifeTrac]] capable of using any agricultural implements.

LifeTrac is also designed with a winch, and is designed to be equipped with well-drilling equipment with 10-foot drilling pipe sections.

As such, the design is one of highest utility and versatility, combining the power of skid loaders with agricultural tractors and construction tractors. A Compressed Earth Block press [[CEB Press]] is designed for use as an implement with [[LifeTrac]], and a backhoe as well.

The unique feature is the modularity and design for dis-assembly. Priority one is lifetime design, where any problem can be troubleshooted and fixed readily. Bye-bye to $1-2,000 transmission jobs at the shop. No transmission is required - it's built-in to the hydraulic drive.

Components are designed to be standard steel as much as possible. The goal is to have the user-owner fully capable of maintenance. By design, no issue in LifeTrac should be more expensive than $250 to fix. Standard steel components (sheet, tubing, shaft, etc.) is used, with no forming or machining outside of minor welding and lathing, for repair and construction of [[OSTrac]].

==General design goals==

*Skid loader concept
*Articulated steering
*4 wheel drive
*2 wheel drive for doubled speed
*Front-end loader
*Backhoe attachment available
*Well-drilling attachment available
*CEB attachment available
*Hybrid between a skid loader, agricultural tractor, and construction tractor

==Specifications==

*5-10 mph in 4 wheel drive
*29 gpm auxiliary hydraulics, 3 channels
*Weight: 3000 lb
*Modular: 2 OSTracs may be mounted together for double traction power
*3500 lb winch
*55 hp Deutz diesel engine
*Four 32 cubic inch hydraulic motors
*3-point hitch
*Power take off, hydraulic - 0-700 rpm

==Maintenance==
*Yearly maintenance costs designed to be no more than $100 with heavy duty usage
:What are the key points in a maintenance check?
:What are the skill sets required to perform a systems check accurately?

==Evolution==
*Flash-steam bladeless turbine drive being explored
*Flash-steam electric hybrid drive being developed

=Versatility=

For us at [http://openfarmtech.org/weblog/ Factor e Farm], LifeTrac will be the backbone of our agricultural, agroforestry, and land stewardship operations. It will also be used in construction, power generation, and possibly other workshop tools. Interestingly, hybrid hydraulic drive also applies to cars - here's an example [http://www.fordmuscle.com/blog/ford-to-build-60-mpg-f150/112114]. The identical hydraulic design, minus agricultural implement features - can be used with a car - simply by using faster, lower-torque wheel motors.

The basic drive is all hydraulic, and all implements are run hydraulically as well. Three hydraulic motors - PTO motor, high torque motor, and winch motor are used for accessory power applications. These can drive the following devices which we are also building contemporaneously:

*Tilt-blade sawmill
*Rototiller
*Post-hole digger/tree planter
*Mixer
*Winch
*Well-drilling rig (future work)

Other implements that we are preparing are:
*[[CEB Press]]
*Backhoe
*Trencher

The unique feature is that the motors can be mounted on the front-end laoder quick-connect plate - which serves, in effect, as an implement attachment mechanism that is much more versatile than a tractor 3 point hitch. All implements may be mounted on the quick-connect

As of 5.24.08, the current working program surrounding LifeTrac is:
[[Image:LifeTrac program.jpg]]

=Articulated Tractor Design=

After examining the function of skid-steering, we decided to add articulated steering with a 2-degree of freedom flexible coupler. The tractor can both bend and rotate around the middle joint. This allows the tractor to minimize impact on the ground when turning. It also allows all 4 wheels to remain on the ground in uneven terrain - where otherwise it is likely that 1 wheel is off the ground often in uneven terrain.

[[Initial LifeTrac design]] is updated here:

==Basic Frame==

Here is the basic frame concept, made of 4x4x1/4" tubing.

[[Image:LifeTrac 2.jpg]]

Here is the frame in practice, starting to be bolted together:

[[Image:frame start.jpg]]

You can see our [http://openfarmtech.org/weblog/?p=201 blog] for additional information.

===Other 2D Drawings===

See [[LifeTrac 2D Drawings]] for other views.

==Engine, Wheel, Hydraulics Addition==

[[Image:lifetrac_bend.jpg]]

===Engine===

Power plant selection will depend on intended fuel source.

A number of different fuel sources, which could be produced at a local scale, could be utilised.

====Pure plant oils====

Oil plants can be grown and using simple technologies the oil extracted and used directly as fuel. A compression ignition (diesel) engine of suitable design is required to allow reliable operation with PPOs.

====Biodiesel====

Biodiesel is a fuel made from plant oils. It involves chemically modifying the oil as to give it properties more closely resembling diesel fuel.

====Biogas====

Biogas can be produced from biomass. It can be used to fuel spark ignition engines or used as the main fuel source for compression ignition engines which use a small charge of oil to begin each combustion event.
[http://en.wikipedia.org/wiki/Jean_Pain System for biogas and heat production from woody biomas]

====Ethanol====

Ethanol is produced through fermentation of sugar and then strength is increased through distillation.

[http://wiki.obed.org.uk/index.php?title=Theory OBED Open Biofuel Engine Development wiki page detailing biofuels]

==Loader Addition==

[[Image:lifetrac_loader.jpg]]

=Hydraulics Design=

==Design Rationale==

Several aspects must be considered:
*Wheel Motor Control
*Turning Cylinder
*Loader
*Auxiliary Hydraulics
===Wheel Motor Control===
A 50/50 flow divider is recommended to make sure that if the front wheels come off the ground with the loader, the back wheels still have adequate flow. Without using a divider, the wheels that come off the ground will spin fast and back wheels will stop - because hydraulic fluid takes the path of least resistance.

One way to address this is with a 50/50 rotary flow divider. Expensive option - such as this 21 gpm divider from Surpluscenter - [[http://surpluscenter.com/item.asp?UID=2008101313500912&item=9-5120-21&catname=hydraulic]]

What are alternative routes? What about a simple ''adjustable flow control valve''?

Would a 50/50 flow divider work - [[http://surpluscenter.com/item.asp?UID=2008101313500912&catname=hydraulic&qty=1&item=9-1048-c]]

==Schematic==
Here is a schematic for the hydraulic power system:

[[Image:LifeTrac hydraulics.jpg]]

==Hydraulics Part Sourcing==

Here are some of the part numbers from [http://surpluscenter.com Surplus Center]:

[[Image:LifeTrac hydraulics parts.jpg]]

Detail of hydraulic pump from Northerntool - [http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200329724_200329724] - and calculations -
===Hydraulic Pump===
[[Image:hydgearpump.jpg]]

===Hydraulic Motors===

These are used on each of the wheels and on the rototiller:

[[Image:wheelmotors.jpg]]

===Calculations===

*1800 RPM gives 26 gpm, so 2000 rpm engine speed of the Deutz 55 hp diesel yields 29 gpm, at a max of 3300 PSI.

**From Surpluscenter tech support, [http://surpluscenter.com/techhelp.asp?UID=2009012117064247&catname=hydraulic] - we have:

[[Image:hydraulicscalculations.jpg]]

**Calculating engine power requirements for the above pump, we have PSI*GPM/1714=3300*29/1714 = 56 hp - or we won't get absolutely high 3600 PSI, '''but only 3300 PSI''', which is still sufficient for any applications.

==Hydraulics Implementation Steps==

The first step of hydraulics implementation is the wheel drive circuit. This includes the hydraulic pump coupled to the engine, the hydraulic reservoir, wheel motors, control valve, cushion valve, hoses, and hydraulic return line filter. Before the main control valve is activated for driving the wheels, we test the pump by observing proper hydraulic fluid circulation back to the hydraulic reservoir. As a safety measure, the wheels are lifted off the ground, to oberve correct direction of motion of each wheel.

Wheel circuit:

[[Image:wheel drive circuit.jpg]]

Test procedure:

#Connect hydraulic pump, main wheel control valve, cushion valve, return filter, hydraulic reservoir.
#Turn on engine, observe flow through tank
#Connect wheel motors
#Disengage motors from wheels or lift wheels off ground, and test wheel motors
##Observe correct forward and reverse motion
#Connect steering cylinder, priority flow divider, and steering cylinder valve
#Drive the tractor on even ground and test steering

===Cushion Valve Plumbing===

From part [http://surpluscenter.com 9-4019-B] documentation:

[[Image:cushionplumbing.jpg]]

===PTO Motor Connection===

[[Image:ptoplumbing.jpg]]

===Post to [http://forums.hydraulicspneumatics.com/groupee hydraulics-pneumatics forum]===

http://forums.hydraulicspneumatics.com/eve/forums/a/tpc/f/8641063911/m/5881043582

Posted 24 May 2008 08:37 PM
Hello,

I am looking for suggestions on the design of the hydraulic system for an articulated tractor/loader that I am building.

Please view the hydraulics design. This includes a 55 hp diesel engine, and a series circuit. The circuit includes: (1), 4 reversible wheel motors for the drive; (2), double-acting turning cylinders for articulated steering; (3) front-end loader circuit; (4) 3 pairs of hydraulic take-offs with 12 gpm quick connects. See:

http://openfarmtech.org/index.php?title=LifeTrac#Hydraulics_Design

Please let me know if the design looks sound. In particular:

1. Is this a sufficient pressure release for protecting the wheel motors:
http://www.surpluscenter.com/item.asp?UID=2008052417204...35&catname=hydraulic

2. Is it better to do an adjustable priority valve: http://www.surpluscenter.com/item.asp?UID=2008052417204...50&catname=hydraulic
or a fixed flow control valve:
http://www.surpluscenter.com/item.asp?UID=2008052417204...-5&catname=hydraulic
for the first divider in the circuit?

3. If I have a 24 gpm flow requirement for a load at the hydraulic takeoffs, is it ok to utilize two takeoffs to feed into one load? I am looking to run a 24 gpm reversible motor, with 12 gpm per takeoff channel.

4. Is the 0-25 gpm flow control valve:
http://www.surpluscenter.com/item.asp?UID=2008052417204...75&catname=hydraulic
suitable for controlling the amount of flow to the hydraulic takeoffs?

Marcin
----
REPLY:
Margin;

This forum is mainly frequented by persons in the Industrial Hydraulic & Pneumatic field.

Try your request at one of these sites:

http://www.offroadfabnet.com/

http://www.machinebuilders.net/forum

http://www.hydraulicinnovations.com/forum

Bud Trinkel
FP Consultant Retired

===Post to [http://www.hydraulicinnovations.com/forum/showthread.php?p=2932#post2932 Hydraulic Innovations]===

This is my hydraulic circuit for a hydraulic, 4-wheel, articulated tractor:

http://openfarmtech.org/index.php?title=Image:LifeTrac_hydraulics.jpg

Is the priority flow divider and flow control valve, plus pressure relief valve for the wheels, sufficient to regulate the flow/prevent overpressure?

I am using:

1. Pressure release for wheel motors:
http://www.surpluscenter.com/item.asp?UID=2008052417204...35&catname=hydraulic

2. If I have a 24 gpm flow requirement for a load at the hydraulic takeoffs, is it ok to utilize two takeoffs to feed into one load? I am looking to run a 24 gpm reversible motor, with 12 gpm coming from each takeoff channel.

Marcin

=Quick Attach Plate=

==Proposed Version==

The Quick Attach Plate converts the loader arms to a quick release mechanism for attachments.

[[Image:quick_attach.jpg]]

[[Image:latch_detail.jpg]]

==Implemented Version==

Here is an easier version, with pins replacing turnable latches. This is the first implementation:

[[Image:quick_quick_attach.jpg]]

=Rototiller=

Initial rototiller design:

[[Image:quick_quick_rototiller.jpg]]

=Tooth Bar=

[[Image:toothbar.jpg]]

[[Image:tooth.jpg]]

[[Image:toothmaking.jpg]]

[[Image:finishedbucket.jpg]]

=Backhoe=

[[Image:Backhoe.jpg]]

=Bill of Materials=

*Wheels
**Shaft collars, 1-7/8", double split - 4 of them - [http://surpluscenter.com/item.asp?UID=2008101413105967&catname=&item=1-2768-193] - $6.75 each
*Tires
**Tire chain quick links, 18 per wheel - 1/4" - [http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92412] - 60 cents each
*Wheel control
**50/50 divider to allow equal flow to front and back wheels when front wheels come off the ground while doing earth digging with loader - [http://surpluscenter.com/item.asp?UID=2008101413105967&catname=hydraulic&qty=1&item=9-1048-c] - $88

=Bill of Materials for Industrial Counterparts=
*One tire and rim - a flat proof one - costs $500 for skid loaders - [http://www.radmeister.com/m-14765-743ds.aspx]. Compare to $5 used truck tires with $35 for open source chains - under $50 for a tire. The latter affords the same traction, at 10-100 times less cost, depending if you count the chains or not.
**Which is more cost effective over a lifetime?

**I've heard that you can fill a tire with insulation foam - as a dirt-cheap alternative to professional puncture-proofing gels. Has anyone done this?
I tried this with a small garden cart. My experience was that because insulation foams are non-elastic, once they are compressed, they stay compressed. This would cause a flat spot on your tire each time you hit a rock.

***That makes lots of sense. Similar foams are available with some rubberiness, for e.g. upholstery.

The tyres of most Elevated work platforms are foam filled. Brand names Genie, JLG. They are sealed with a 3/8 (10mm) bolt. I presume the tyre needs to be sealed while the foam goes off

=Attachments on Other Machines=
*Dingo attachments - [http://www.toro.com/professional/sws/loaderattach/photogallery_attachments.html]

=Cost Comparisons to Industrial Counterparts=

[[Image:lifetraccomparison.jpg]]

*NOTE: Industrial prices are taken largely from Northern Tool catologue - [http://www.northerntool.com/] - your local, global supply chain.
*Commercial hydraulic rotary well drilling rig quote - [http://www.hydra-jett.com/1573687.html]

=Outstanding Tech Questions=

==== Horses ====
In terms of biofuels conversion, horses may be far more efficient than tractors. In no-till or low-till permaculture farming with local fuel production, tractors might not make sense at all.
http://www.lowtechmagazine.com/2008/04/horses-agricult.html

==== Response ====
One would have to do more careful, side-by-side analysis on the above. A horse, whether used or not, eats the equivalent biofuel crop for 1 gallon of liquid fuel every day. A tractor, on the other hand, eats zero gallons of fuel when it is not used.

== See also ==
See [[LifeTrac Red Pages]]
* [[LifeTrac Questions]]

[[Category:Hydraulics]] [[Category:LifeTrac]]
[[Category:Global_Village_Construction_Set]]
[[Category:OSA]]

MicroTrac

2009-09-27T08:55:56Z

Whitworthsocket: /* Resource Map */

{{site header}}
[[Image:Hoselengths.jpg]]
[[Image:Microtrac4.jpg|thumb]]
[[Image:MicroTrac1.jpg|thumb]]
[[Image:MicroTrac2.jpg|thumb]]
[[Image:MicroTrac3.jpg|thumb]]

MicroTrac is a small scale, walk-behind version of [[LifeTrac]]

=Industry Standards=
*The [http://www.abbysguide.com/ope/reviews/39-0-1.html BCS Tiller] is the main competition.

=Tools=
*Tiller

*Mower

*Chipper
-Laimet conical screw design. Makes nice big, uniform sized chips.

=Design=

[[File:Microtrac_Design1.blend]]

=Engine=
The engine will be a modular removable unit consisting of engine, fuel tank, hydraulic pump, hydraulic reservoir, and frame. The frame will be the hydraulic reservoir, made out of 4x4" square tube.

==Specifications==
Engine should be a 12-20 hp 1 cylinder diesel engine, with air cooling. The engine will run the hydraulic pump.

We have a 17.5 HP engine.

Dimensions: 18x16x13"
Shaft: 1x?"

Turns CW from above. CCW from below.

==Sourcing==
**[http://desc.shop.ebay.com/items/Generators__diesel-hp-cylinder_W0QQLHQ5fTitleDescZ1QQLHQ5fPriceZ50Q2eQ2e2Q2c000Q40cQQQ5ftrkparmsZ66Q253A2Q257C65Q253A15Q257C39Q253A1QQ_dmdZ1QQ_dmptZBIQ5fGeneratorsQQ_in_kwZ1QQ_ipgZ50QQ_mPrRngCbxZ1QQ_okwZdieselQ20hpQ20cylinderQQ_sacatZ106437QQ_scZ1QQ_sopZ15QQ_trksidZp3286Q2ec0Q2em14?_fpos=64469&_fcid=1&gbr=1 from here]
*[http://cgi.ebay.com/New-Onan-2-Cylinder-Diesel-Engine-14-HP-DJEAMMS4496A_W0QQitemZ330310425172QQcmdZViewItem 14 hp 2 cylinder engine no starter $975]
*[http://cgi.ebay.com/NEW-Aurora-6000-Watt-Diesel-Generator_W0QQitemZ380106916786QQcmdZViewItemQQptZBI_Generators?hash=item380106916786&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A15|39%3A1|240%3A1318 11 hp 1 cylinder generator $899.00]
*[http://cgi.ebay.com/Heavy-Duty-Silent-Diesel-Generator_W0QQitemZ380106472733QQcmdZViewItemQQptZBI_Generators?hash=item380106472733&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A15|39%3A1|240%3A1318 13 hp 1 cylinder silent $1300]
*[http://cgi.ebay.com/Industrial-8-250-Watt-Electric-Start-Generator_W0QQitemZ330311074168QQcmdZViewItemQQptZBI_Generators?hash=item330311074168&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A15|39%3A1|240%3A1318 13 hp $695 GAS]
*[http://cgi.ebay.com/23HP-Water-Cooled-Diesel-Engine-with-radiator_W0QQitemZ180331677925QQcmdZViewItemQQptZBI_Farm_Supplies?hash=item180331677925&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A1|39%3A1|240%3A1318 23 hp water cooled diesel engine with radiator $1000 - $1349]
*[http://cgi.ebay.com/WHITE-FIELD-BOSS-2-62-DIESEL-UTILITY-TRACTOR-ONE-OWNER_W0QQitemZ370165894383QQcmdZViewItemQQptZTractors?hash=item370165894383&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A1|39%3A1|240%3A1308 62 hp 4 cylinder tractor $1828 ]
*[http://cgi.ebay.com/BELARUS-505M-FARM-TRACTOR-NO-RESERVE-FIXER-UPPER_W0QQitemZ250380038290QQcmdZViewItemQQptZTractors?hash=item250380038290&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A1|39%3A1|240%3A1318 65 hp 4 cylinder tractor $710]
*[http://cgi.ebay.com/DEUTZ-DIESEL-POWER-UNIT-ENGINE-MOTOR-F3L-1011-40HP-3cly_W0QQitemZ300296916733QQcmdZViewItemQQptZBI_Farm_Supplies?hash=item300296916733&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A1|39%3A1|240%3A1318 40 hp 3 cylinder $1500 - $2300 ]
*[http://cgi.ebay.com/John-Deere-830-Diesel-Tractor_W0QQitemZ170306687641QQcmdZViewItemQQptZTractors?hash=item170306687641&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A1|39%3A1|240%3A1318 35 hp 3 cylinder tractor $1185]
*[http://cgi.ebay.com/ebaymotors/Volkswagen-Beetle-New-GLS-TDI-2000-VW-BEETLE-GLS-TDI-DIESEL-1-OWN-5SP-SNRF-NO-RESERVE_W0QQcmdZViewItemQQ_trkparmsZ66Q3a2Q7c65Q3a1Q7c39Q3a1Q7c240Q3a1318QQ_trksidZp3286Q2ec0Q2em14QQhashZitem120385960498QQitemZ120385960498QQptZUSQ5fCarsQ5fTrucks 90 hp 4 cylinder diesel 2000 vw beetle $2000]
*[http://cgi.ebay.com/NEW-11-hp-air-cooled-diesel-engine-12v-electric-starter_W0QQitemZ330306984305QQcmdZViewItemQQptZLH_DefaultDomain_2?hash=item330306984305&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A1|39%3A1|240%3A1318 11 hp 1 cylinder $400]

**[http://desc.shop.ebay.com/items/__diesel-engine-hp-cylinder?LH_TitleDesc=1&LH_Price=50..2%2C000%40c&_trkparms=66%253A2%257C65%253A1%257C39%253A1&_dmd=1&_fsct=&_in_kw=1&_ipg=50&_mPrRngCbx=1&_oexkw=&_okw=diesel%20engine%20hp%20cylinder&_sop=1&_trksid=p3286.c0.m14&_pgn=4 more from here ]

*[http://cgi.ebay.com/13-7-HP-INDUSTRIAL-DIESEL-ENGINE-PERKINS-402C-05_W0QQitemZ380104518370QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item380104518370&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A1|39%3A1|240%3A1318 13.7 hp 2 cylinder $666 ]
*[http://www.uspowerco.com/inventory_item.php?id=272 Perkins 402C 13.7hp 2 cylinder Same as above, asked for quote 3/5/09 talked to jeff]

=Hydraulic pump=

==Specifications==
*10.1 GPM at 3600 RPM and 2500 PSI, requires 17.3 hp to drive it - best match to available engine - [https://surpluscenter.com/item.asp?UID=2009050111530930&item=9-1897-A&catname=hydraulic]

==Sourcing==
*.677 cu in, 10.1 gmp @3600 RPM, 3000 PSI max, 4000 RPM max, $180 - [https://surpluscenter.com/item.asp?UID=2009050111530930&item=9-1897-A&catname=hydraulic]

=Coupler=

=Wheels=
[[Image:Wheelmotors.jpg|thumb|32 cu in wheel motor, 5130 in oz torque, 145 rpm at 20 gpm]]

*one set of drive wheels in the middle balanced with the engine so the Microtrac can be rotated easily, with a motor on the side
*doubled up for traction
*have support wheels on the back sides so it doesn't tip easily
*drive wheels the same as lifetrac, 30" high 10" wide

=Bill of Materials=

==Engine Cage and Controls==
[[Image:microtrac_engineback1.jpg|thumb]]
[[Image:microtrac_engineback2.jpg|thumb]]
[[Image:microtrac_pump677.jpg|thumb]]
[[Image:microtrac_valve.jpg|thumb|3 spool, OC, 25 gpm valve]]

{| border="1"
|-
|Part - Cage || Weight || Price
|-
|[[https://surpluscenter.com/item.asp?UID=2009050111530930&item=9-1897-A&catname=hydraulic .677 cu in, 10.1 gmp @3600 RPM, 3000 PSI max, 4000 RPM max, $180]] || 9 lbs || $181
|-
|[http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_12006_12006 NT filter] [https://surpluscenter.com/item.asp?UID=2009050412033450&item=9-059&catname=hydraulic or SC filter] || 2 lbs || $17
|-
|[http://www.mcmaster.com/#6408k15/=1gl6m4 or type E coupler half 1/4" key 2.5" o'all long (2 of these,for] || .65 lbs || $9.86
|-
| Parts total || 12 lbs || $220.85
|}

{| border="1"
|-
|Part - Controls|| Weight || Price
|-
|[https://surpluscenter.com/item.asp?UID=2009041514290385&item=9-7175&catname=hydraulic 3 spool valve] || 35 lbs || $200
|-
| Parts total || 35 lbs || $200
|}

Other choices, not used:
|-
|[http://www.grainger.com/Grainger/items/4X193 L095 coupler half 1" shaft 1/4" key 1-1/16" long] || .65 lbs || $15.28
|-
|[http://www.grainger.com/Grainger/items/1A925 L095 hytex coupler insert] || .04 lbs|| $18.29
|-
|[http://www.grainger.com/Grainger/items/4X191 L095 coupler half 3/4" shaft 3/16" key 1-1/16" long] or [http://www.grainger.com/Grainger/wwg/productIndex.shtml?from=Search&newSrch=yes&operator=keywordSearch&search_type=keyword&action=Go%21&QueryString=6X072&submit.x=361&submit.y=34 5/8"] || .7 lbs || $15.28

*Note on 3 spool valve - about 1900-3400 PSI relief setting

==Frame Metal==

2x2x1/8" is 3.05 lbs/ft

Steel @ $0.70 per/lb

{| border="1"
|-
|Part || Weight || Price
|-
|2x2x1/8" square tube 29" long, x 6 || 44.22 lbs || $30.95
|-
|2x2" square tube 24" long, x 4 || 24.4 lbs || $17
|-
|2x2" square tube 20" long, x 8 || 40.66 lbs || $28.46
|-
|2x2" square tube 7" long, x 2 || 3.55 lbs || $2.49
|-
|7x25" plate 1/4" thick || ||
|-
| Tubing total || 125 lbs || $94
|-
|}

Total length of 1/8" tubing - 37 feet, or 4 sticks of 10' lenght.

+17.5 HP gas engine 60 lbs $?

+resirvoir 10 lbs $?

+battery 20 lbs $23

Total: 215.66 lbs

=Power Cube (MicroTrac engine cube) Details=
[[Image:microtrac_couplerhalf1.jpg|thumb|Engine-side coupler half, 1" shaft, $9.86, Type E]]
[[Image:microtrac_couplerspider.jpg|thumb|Spider insert, 1" shaft, coupler half, $14.36, type E]]
[[Image:microtrac_couplerhalf2.jpg|thumb|Pump-side coupler half, 5/8" shaft, $9.86, Type E]]

*The coupler halves and spider are shown in the pictures, from McMaster Carr [http://www.mcmaster.com/#6408k15/=1gyaq6 page 1157]

=Power Calculations=
==Pump==
[[Image:hydcalc.jpg|thumb|Hydraulics Calculations from [https://surpluscenter.com/techhelp.asp?UID=2009041610053391&catname=hydraulic]]]
*From [https://surpluscenter.com/] - Pumping = 1 Hp = 1 GPM x 1500 Psi - (linear relationship i.e. 2 GPM @ 1500 Psi = 2 Hp)
**For the above pump, 14.2 gpm with 3000 psi indicates 28.4 hp requirement
*Hp to drive hydraulic pump = Psi x GPM / 1714
**For the above .97 cu in pump, 3000*14.2/1714 = 24 hp
**If we run at 2200 psi => 18 hp required
**For .86 cu in pump, need 3000*12.6/1714 = 22 hp
**For the same with 2500 psi, 18.3 hp

==Power Available==
*Assuming 85% pump efficiency, we have 17.5*.85=14.8 hp power available to the machine
==Wheel Motor Calculations==

*32 cu in wheel motor: 20 gpm, 5170 in lb torque, 145 rpm
**Using 12 gpm, 5170 in lb torque, at 87 rpm - uses 7 hp of the engine

==Spider Torque Rating==
The Hytrel coupler spider has a 401 in lb torque rating. This is at 3600 rpm. If this pump is driving a hydraulic motor at 87 rpm (wheel motor at 12 gpm fluid flow, at its rated torque), what would be the maximum torque that the 87 rpm could have? 401*3600/87 = 16600 in lb. That is well within the 5130 in lb torque of the wheel motor. Coupler spider will hold up.

=Resource Map=

(could use more review)

Reviewers:
*http://www.tractorbynet.com/forums/build-yourself/140170-homemade-modular-hydraulic-engine.html
**No response as of 4.28.09
*http://forums.hydraulicspneumatics.com/eve/forums?a=tpc&s=4721063911&f=8641063911&m=74110526&r=74110526#74110526
**Useful response, including hydraulics primer, Mr. Hanson's contact as a consultant, etc.
**The response claims need for 30 hp if we want 15 gpm at 2200 psi. We have 12 gpm at 2500 psi.
***CadTrac uses 16 gpm pump and 18 hp engine, at 2000 psi for 1/2 of the flow (to wheels) and 1000 psi to rest of flow (loader)
Coupler info:
*http://www.lovejoy-inc.com/uploadedFiles/Catalogs/jw.pdf
*http://www.ohiobelting.com/pdfs/lovejoycplg.pdf

After using the walk behind thai Tractors
http://www.siamkubota.co.th/en/product_detail.aspx?pid=16&cid=3
http://en.wikipedia.org/wiki/File:1-achsiger_Traktor.jpg

For Plowing and using a small dozer blade and towing a trailer.
I can say that your effective Uni wheel will be a pain in the backside to use.
having short legs to help stabilize. Is a huge basic design flaw.
Trust me you are working hard with these machines plowing. You have to apply downward pressure to the handlebars
to get the coulter or disk into the ground then modify that pressure to maintain cutting depth.
You dont want to be trying to balance the tractor in the vertical plane as well.
What about surface imperfections that will cause imbalance.
Either get a Gyro or make it two wheels that are spaced at least 900mm apart.
If you are going to go Hydraulic that may mean two drive motors and spools so that you can turn easily.
Regards Whitworth

=Notes=
*On calculations (right picture) - formula for horsepower to drive pump (with 1714 factor) includes the efficiency of the pump (about 85%)

=Parts Buildout=

[[Image:microtracpartsbuild.jpg]]
[[Category:MicroTrac]]
[[Category:LifeTrac]]
[[Category:Hydraulics]]
[[Category:OSA]]