Page 6 of 9 FirstFirst 123456789 LastLast
Results 76 to 90 of 125
  1. #76
    Join Date
    Dec 2013
    Location
    Sydney
    Posts
    201

    Default

    Quote Originally Posted by simonl View Post
    Now ive bought a valve for no reason!
    Far from no reason, now you have an excellent excuse to start another hydraulic project .

    Tilting trailer? Stump grinder? Electric press?

    Am I being helpful?

    Graham.

  2. #77
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,779

    Default

    No. You're just being a trouble maker!

    In truth I have any number of projects waiting for me. not including projects in the garden, I also have my mill to finish, in 3 months I'll have a 1000 x 630mm surface plate that will need a stand, and I also have a 1200mm pan brake that is half finished that I seriously want to complete.

    Simon
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  3. #78
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,435

    Default

    Hi Guys,

    Too many projects, not enough hours in the day...
    Best Regards:
    Baron J.

  4. #79
    Join Date
    Mar 2014
    Location
    South of Adelaide
    Posts
    1,225

    Default

    Hydraulic panbrake

  5. #80
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,779

    Default

    The other day I finished wiring up the electric hydraulic pump for the log lifter. I was quite pleased with myself, watching the lifter go up and down at the push of a button. I then figured it was time to stress test it so I plonked on a massive log that had been laying around. It was too knarled and big to split by hand, I had tried but I got sick of watching the log splitter bounce off it.

    Half way up and the lifter stop lifting. The electric motor was spinning freely (without any load) but no movement. I thought maybe I sheared off my little connecting shaft I made, but when I took apart the motor and pulled it out, it was still OK. It appears as though something in the hydraulic pump has finally given in. I will have to look further into this but it seems a little disappointing.

    That second spool valve may have a use quicker than I thought. I may end up connecting the log lifter up to the main pump, piggy backing the two spools, one to lift the logs and the other to split them. I'm just worried about the flow into the small ram, I will need some serious flow control to that.

    Simon
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  6. #81
    Join Date
    Apr 2012
    Location
    Healesville
    Posts
    2,129

    Default

    Quote Originally Posted by simonl View Post
    I'm just worried about the flow into the small ram, I will need some serious flow control to that.
    Simon
    You could put an adjustable stop on the lever or spool to limit the opening of the valve.

    shed

  7. #82
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,779

    Default

    Yes I have thought of that. It may be the prefereable method to a flow restrictor as a flow restrictor will drive up the system pressure which puts unnecessary stress on hoses and components. Also, with two of these spool valves connected in line, it will increase the back pressure on the other spool valve and I don't know enough about hydraulics to know if that is an acceptable design for these particular spool valves.

    An adjustable limiting stop is probably the safest way to go.

    Simon
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  8. #83
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,779

    Default

    Done some more work on the log splitter.

    I have finished the actuator assembly that controls the throttle in response the the engine RPM measured by the electronic speed controller. Not a terribly technical job but fiddly non the less. One main issue was the fact that the actuator only moves a maximum of 12mm from fully out (idle) to fully in (WOT) as this needs to move the trottle shaft about 80 degrees (from idle to WOT). Sure, it can and was done with levers but it meant an increase in force required to do the job. The actuator already needed to work against a rather stiff internal spring designed to be a failsafe, returning the engine to idle if power is removed from the controller or actuator. As well as that, there are a couple of springs on the carburettor including a spring on the axillary power pump, which is an internal piston pump designed to deliver instant fuel when the trottle is pumped.

    With the setup I made, the ratio of the throttle linkage movement to actuator movement is about 4.7:1 This kept the lever sizes reasonable including the lever on the throttle body.

    Pic 1: All the parts laid out before assembly. They were all made from alluminium and SS. The moving parts are mostly aluminium, in order to keep moving masses to a minimum in order to help with response.

    Pic 2: The linear proportional actuator dis-assembled. I removed the factory spring and replaced with one of a slightly less spring constant in order to help it overcome other forces.

    Pic 3: Throttle body before adding the linkages

    Pic 4: New linkage added

    Pic 5: Base plate for the actuator assembly. It attaches on an inlet manifold bolt, an exhaust bolt and two smaller M6 holes on the top of the rocker cover that were pre-existing.

    Pic 6: Actuator with linkage attached and screwed to the alluminium housing that attaches to the SS RHS

    Pic 7: SS RHS assembly attached to base plate

    Pic 8: Completed and installed actuator assembly.

    I'm yet to make the necessary adjustments on the electronic engine speed controller yet. These include ramping speed from idle, droop adjustment, gain, stability and maximum engine rpm.

    Cheers,

    Simon
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  9. #84
    Join Date
    Apr 2012
    Location
    Healesville
    Posts
    2,129

    Default

    Nice neat job simon, one thing you might want to do is put a hose clamp on that fuel filter before it starts squirting fuel on
    that hot exhaust manifold, your m8's at work would never let you live it down if they had to come and put it out

  10. #85
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,779

    Default

    Yea. You're right. Sometimes im too busy tackling the bigger issues and forget about the easy stuff thats equally important!

    Simon

    Sent from my SM-G900I using Tapatalk
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  11. #86
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,779

    Default

    Well after a bit of tinkering I got the engine speed governor to kinda work. I have the actuator moving the carby throttle in response to engine load in an attempt to maintain a pre-determined engine RPM.

    I'm having problems with the stability, it's currently hunting and when the engine is really loaded up it overshoots and revs the crap out of the engine. I'm surprised it hasn't thrown a 35 year old piston out the side on one occasion!

    Like I said, there are two adjustment trim pots called "stability" and "gain" which are designed specifically to smooth out this erratic behaviour. I have ran out of time today but I'm confident that after some trial and error, I will get a satisfactory result.

    It's still nice to see things working though.... well kinda.

    Simon
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  12. #87
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,435

    Default

    Hi Simon,

    Feedback mechanisms can be a nightmare to tune !

    I used to cringe at having to do bode plots of systems. I'm sure that you can find something on the net that might help.
    The letters P.I.D strikes terror and fear... I'm very glad that I can now forget it ever happened.
    Best Regards:
    Baron J.

  13. #88
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,779

    Default

    Underdamped Oscillations. Yep I suspected I may have a job on my hands with this system. I'm not at the end of my tether yet as I have a few things to play with which may help with the situation. It's just a matter of changing one thing at a time and see what affect it has on the system. I have not really had much of a play with the Gain and Stability trimpots, I may yet establish a balance with further adjustments of these two parramaters alone.

    As a last resort I could just introduce a mechanical damping system with an oil filled dash pot! I deliberately left the pivot pin on the linkage system hanging out, longer than needed just in case I need to add something to the system.

    Simon
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  14. #89
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,779

    Default

    OK I have had a bit more of a play. I have managed to mostly get rid of oscillations when the load is even and unchanging. Biggest issue is over shooting the target rpm range once an extra load is placed on the engine and it then over-compensates with throttle to the point it over-revs. I think it maybe my own fault. At this stage I am running this engine without a flywheel. It was an automatic which means it came with a flex plate, which essentially is a very lightweight ring gear for the starter motor to engage with. An engine coupled to a manual car has this ring gear as part of a much heavier flywheel. I think a flywheel will mostly dampen out the hi's and low rpm's keeping a more constant rpm range, making the job of the governor much easier.

    Not a huge job to make one. Not exactly sure how heavy to make it but I assume the heavier the better, within reason. It's not like I want to engine to be super responsive in changes in rpm, in fact I want the opposite.

    Simon
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  15. #90
    Join Date
    Aug 2006
    Location
    Melbourne
    Posts
    1,105

    Default

    Can't you just grab a flywheel from a manual version of that engine? Might save you some time.

Similar Threads

  1. Log splitter Advice needed
    By simonl in forum METALWORK GENERAL
    Replies: 45
    Last Post: 1st May 2018, 07:46 PM
  2. Extraordinary Hydraulic Wood Splitter
    By Oldneweng in forum GENERAL DISCUSSION / OFF TOPIC
    Replies: 29
    Last Post: 28th Aug 2017, 10:51 PM
  3. Firewood Splitter Modifications
    By Oldneweng in forum TRAILERS & OTHER FABRICATED STUFF
    Replies: 45
    Last Post: 1st Aug 2017, 05:56 PM
  4. Hydraulic ram
    By GSRocket in forum METALWORK GENERAL
    Replies: 8
    Last Post: 6th Oct 2012, 10:19 AM
  5. Hydraulic Log Splitter
    By Geoff Dean in forum METALWORK GENERAL
    Replies: 8
    Last Post: 15th Apr 2008, 12:01 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •