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MicroTrac Build Instructions

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  1. Cut flats for power cube frame (20x20x30 frame)
    1. See 5 sides for detail
    2. Keep width to exactly 20” so PC doesn’t stick out beyond frame
  2. Cut short stubs of ½” hose for engine vibration mounts
  3. Cut [2] large tank sides
    • Weld in [2] ¾” nips for 2 returns
      1. Make these with a 90 degree elbow for going below fluid level
    • Weld in [2] straight ¾” pipe for suctions
    • Weld in a ⅛” return for case drain
  4. Cut top side - including filler hole
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MicroTrac Power Cube Cut List

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All ¼” steel

  • [2] ¾” NPT black pipe nip, 4”
  • [4] 4” x 20” flat
  • [1] 4” x 16” flat (engine mount)

Totals:

  • 2 black pipe nips
  • 8’ of 4” flats
  • 24’ of 2” flats
  • ...
  • For a 64 hp power cube, add:
    • [4] 6”x20” flat

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TOTALS for 2 Master Cubes

  • 4 black pipe nips and elbows (return + suction)
  • 16’ of 4” flats
  • 48’ of 2” flats
  • 7’ of 6” flat

Second Power Cube Suction on the Right Hand side of the tank 4” from edge for second Power Cube

Frame is ¼”x2” flat throughout

Motor mount - 4” wide bar

No battery mount needed

Frame is ¼”x2” flat throughout

Add bolt pattern to engine mount

Second large return to tank

4” wide

Small case drain return to tank

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Small Power Cube Cut List

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All ⅛” steel for small cube, or ¼” if double

  • [8] 2”x13 = 78”
    • [16] 2” x 20” flat=280’
  • [1] 4”x16”

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TOTALS

  • 35.5’ of ⅛”x2” flat - that’s a lot for a power cube
  • 16” of ¼”x4” flat

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Tensioner

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Approach

  • Get everyone started
  • Hydraulic Tank
    • Clean
    • Weld
    • Epoxy
    • Pressure test
  • Full arm dimensions

Cut List - ½”. 4,5,6

  • [1] 4x11.5 (top mid)
  • [2] 5x20 (front + back)
  • [2] 5x5.5
  • [2] motor faces
  • [2] motor backs
  • [4] fillers

20”

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Overall Totals

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All ¼”:

  • 10’ of
  • 30’ of 4” flats
  • 200’ of 2” flats
  • 10’ of 6” flat
  • 1 sheet of 4x8 steel

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¾” steel:

  • ¾”x10” bar - 5’ long

½” steel:

  • 2” bar - 20’
  • 2.5” bar = 20’
  • 4” bar - 30’
  • 6” bar - 10’ (tensioner)
  • 5” bar - 20’ (loader)
  • 8” bar - 10’
  • 12” bar - 10’

1” rebar

  • 20’

3” shaft - 18’

2” shaft - 12’

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Tractor Build

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  • MicroTrac
  • LifeTrac
  • Gasifier
  • Power Cube
  • Solar Power Cube
  • Trencher

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  • Lex
  • Josh
  • Roberto
  • Ahmed
  • Abe
  • Oliver

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MicroTrac

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  • Hydraulics Calculations - Speed.
    • Toro dingo speed - 3-4.5 mph depending on model.
    • Bobcat T450 - tracked - 7.3 mph
  • Microtrac - series operation - 45.6 cu in - .2 gallon - so 25 gpm max (30 intermittent) gets us up to 150 RPM (intermittent) = 375 feet per minute = 4.3 mph
    • Walking speed - 3.1 mph
    • With 24 gpm, 312 fpm = 3.5 mph with series drive
  • Speed solution: 15.9 cu in motor, 5850 in lb - 18/24 gpm for 260/350 rpm
    • 5” to tooth edge of sprocket = 1250 lb
    • Speed at 24 gpm in series drive=875 fpm=9.9 mph
      • Speed in parallel drive - 5 mph

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HP to drive a pump - PSI*GPM/1714

HP = 2000*14/1714 = 16.3

HP=2300*12/1714=16.1

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We can get 2300 PSI with 12 GPM

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Prince - 8 gpm at 2000 RPM = 14 GPM at 3600 RPM

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MicroTrac Hydraulics - 32 hp

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Female

12 GPM

Auxiliary

(Tiller, Trencher, Mower)

PC 1 Inlet

¾” hose

Return

to Tank

40 GPM ISO 7241-1 B

PC 2 Inlet

Parallel Wheel Drive

Loader

Series drive

Return

to Cooler

40 GPM ISO 7241-1 B

Notes:

  1. System inlets make sense to be multiple 12 GPM feed lines - as we have multiple hydraulic pumps
  2. Return makes sense to be one line, since it’s all going back to the hydraulic reservoir
    1. There are 2 full returns

Flow Control Valve

for Drive Speed

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New Power Cube Coupler

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2” schedule 80 pipe as DIY pump mount, with 2 flanges welded for the engine and pump

Notes:

shaft

Engine

Pump

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MicroTrac Phases - 32 hp

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Phases:

  • Start with Wheel Drive
  • Add loaders
  • Add Auxiliary

Subphases:

  1. 1 power cube, 3 spool valve
  2. 2 power cubes, 3 spool valve
  3. Add load

Wheel Drive - parallel and series from one 3-spool valve?

  • First 2 levers - parallel
  • 3rd lever - non-turning series for rapid motion
  • Not possible. Red path 1 short circuits in parallel mode

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MicroTrac Phases - 32 hp Parallel

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Phases:

  • Start with Wheel Drive
  • Add loaders
  • Add Auxiliary

Subphases:

  • 1 power cube, 3 spool valve
  • 2 power cubes, 3 spool valve
  • Add load

Wheel Drive -

  • Parallel

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LifeTrac Hydraulics - 64 hp

Doable but use Joystick Valves Instead

PC 1 Inlet

¾” hose

Return

to Tank

PC 2 Inlet

Return

to Cooler

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Notes on Drive Power:

  • D1 - PC 1 + PC 2
  • D2 - PC 3 + PC 4
  • Examples:
    • D1 - implement only, D2 - wheel drive only
    • D1 only - Travel: series drive, max speed
    • D1 only, parallel - slow work, high torque

PC 4 Inlet

Return

to Tank

PC 3 Inlet

motor

wheels

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LifeTrac Hydraulics with Joystick Valves - 64 hp

PC 1 Inlet

PC 2 Inlet

Return

to Cooler

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Notes on Drive Power:

  1. Use two 3 spool joystick valves, 25 gpm:

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PC 4 Inlet

Return

to Tank

PC 3 Inlet

wheels

Parallel Forward (one valve, 2 spools)

Parallel Reverse

Spool 1: Left Motor, Forward + Reverse

Spool 2: Right Motor, F + R

Spool 3: Loader Arms

Series Forward (2 valves, first 2 spools)

Series Reverse

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What do you suggest for the 16hp pump mounts? We are making 6 Power Cubes - but they are way simpler than last time - no fuel tank, no solenoid, no battery. We make 2 or 3 with large coolers as Mother Cubes, and the remaining cubes are just engine + pump, sucking from Mother Cubes. I think 2 Mother Cubes, each with 3 outlets - one Mother Cube runs 3-4 smaller cubes.

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We have a pump mount from last year, but it is rather long. And didn't we need to drill it out anyway because the bolt pattern was wrong?

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I'd prefer trimming the engine shaft down and making our own pump mounts. While that is somewhat complicated, it does save precious space. One thing we can do is run the engine (it's recoil start) and take a grinder to it for a nice cut

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Did you leave the coupler maker here with me, or did you take that home with you?

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Check out our PC - https://docs.google.com/presentation/d/1qFTCY8NBRKJCVjVTwvB_5yZROeEpCg_LLxgLip-GoRI/edit#slide=id.g244eeabb5b_0_403

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Hydraulic cooler calcs say - for 64 hp - we need 25% heat rejection - need 16 hp heat rejection - or 40,000 to 50,000 BTU/hr from your page. Hayden 1284 or 1290 could do it. 32 to 36 GPM. So we need 1292 to get up to 48 GPM - so 4 12GPM pumps would be the way to go. 12 GPM at 16 hp means we can achieve 2300 PSI, which is acceptable:

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HP=2300*12/1714=16.1

We can get 2300 PSI with 12 GPM

So that the travel speed on the microtrac is 4 mph in parallel drive and 8 mph on series drive.

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MicroTrac Hydraulic Design with 15.9 cu in motor

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  • 24 GPM system, 12 GPM x2 engine, 2300 PSI, 16 hp engines x2
  • Issue: make sure that the tracks on the sprocket do not hit the fitting on the motor, or anything else
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Nut

Coupler

Motor

Fitting

8 tooth sprocket welded to coupler

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LifeTrac

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4.5” bolt circle

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Gasifier

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  • MicroTrac
  • LifeTrac
  • Gasifier
  • Power Cube
  • Solar Power Cube

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Power Cube

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  • Build 4 for LifeTrac
  • Build 2 for MicroTrac
  • Determine best strategy for Mother Cube in the 4 Power Cube Configuration

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Solar Power Cube

Working Page

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  • BOM - translate it to Google Spreadsheet
  • CAD
  • Tooling - the usual + small lathe
    • Need set screws
  • Tap and die set - for whatever tap we have, we need a set

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Notes:

  • .12 GPM = 28 cu in = .0.6 RPM = 1.2 fpm
  • 40 tooth on the pump
    • 1” wide belt
  • 20 teeth on the motor
    • Motor is 450 RPM

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LifeTrac v17.10