Page 2 of 3 FirstFirst 123 LastLast
Results 16 to 30 of 45
  1. #16
    Join Date
    Apr 2018
    Location
    Drouin Vic
    Posts
    386

    Default

    Quote Originally Posted by grunto View Post
    Pro Tech Laser are in Rhur St. What you are after doesn't look to complex - I can knock up a drawing if you sketch up what you need (might help with other companies if you are getting some quotes).
    That's very generous Grunto. Thank you. I'm tossing around some different design options in my head at present, there are several different design features on the commercial grapples that I think I can amalgamate and improve upon in a couple of ways. I'm going to try and come up with some ideas and dimensions on paper but I'm juggling family commitments over the next week and might not be able to get a run at it. I'll probably post a design sketch or two on here and ask for feedback about a couple of things.

    Currently I'm considering something along the lines of this model, but with a split top section
    https://www.everythingattachments.co...ta-cmp-rrg.htm

    I also have another couple of questions for the brains trust, as this is a new level of fabrication for me...
    The round tube that is used as a cross member in the upper and lower assemblies of the unit above, and in the top section of the green one in my original picture; what would be a suitable high-tensile tube for that purpose? I plan on using Bisalloy 400 plate or similar for the tines so would want to use a HT material for the round as well. Aus Tube Mills' C450 appears suitable..? Would this be difficult to source in smallish quantities?
    Most of my fabrication projects to date involve RHS and SHS but it makes sense to use round tube where it has to pass through other components, i.e. easier to make a line of round holes than square ones, and keeping weight under control will be important rather than my usual thing of mild steel RHS and go big with the wall thickness.

  2. #17
    Join Date
    Apr 2012
    Location
    Healesville
    Posts
    1,791

    Default

    Pete i used duraflex when i made the rippers for a yeomans plow that i built, my thinking at the time was that if the leading edge's suffered from abrsision then they could be repaired with hard facing rods, they hardly wore at all.
    Bisalloy is costly and usualy only used on the cutting edges. I used yeomans wombat points.
    Then you may also have problems with welds cracking as it is hard and wont have the flex that is needed in this application.
    To weld it properly it also needs preheating and low hydrogen.

  3. #18
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    55
    Posts
    1,843

    Default

    Pete, just some random thoughts without any personal experience in building one.
    Iíd be inclined to stick with standard steels, use a stiff core for the bits that will be a PITA if they bend etc and go lighter on the rest with thought around stress points and later repair IF required.
    My logic being that you wonít be abusing it like a unit being used commercially, you will be keeping an eye on it for any signs of issues, and itís not something that is likely to have a catastrophic failure.
    Iím typically one to just overbuild things, but slowly coming to realize that itís unnecessary for most of the stuff I do, and just makes the project harder and more expensive.

    Just my 2c

    Steve

  4. #19
    Join Date
    Mar 2014
    Location
    South of Adelaide
    Posts
    918

    Default

    Quote Originally Posted by Pete O View Post
    That's very generous Grunto. Thank you. I'm tossing around some different design options in my head at present, there are several different design features on the commercial grapples that I think I can amalgamate and improve upon in a couple of ways. I'm going to try and come up with some ideas and dimensions on paper but I'm juggling family commitments over the next week and might not be able to get a run at it. I'll probably post a design sketch or two on here and ask for feedback about a couple of things.

    Currently I'm considering something along the lines of this model, but with a split top section
    https://www.everythingattachments.co...ta-cmp-rrg.htm

    I also have another couple of questions for the brains trust, as this is a new level of fabrication for me...
    The round tube that is used as a cross member in the upper and lower assemblies of the unit above, and in the top section of the green one in my original picture; what would be a suitable high-tensile tube for that purpose? I plan on using Bisalloy 400 plate or similar for the tines so would want to use a HT material for the round as well. Aus Tube Mills' C450 appears suitable..? Would this be difficult to source in smallish quantities?
    Most of my fabrication projects to date involve RHS and SHS but it makes sense to use round tube where it has to pass through other components, i.e. easier to make a line of round holes than square ones, and keeping weight under control will be important rather than my usual thing of mild steel RHS and go big with the wall thickness.

    HT tube is over kill for what you are making, medium wall MS pipe or heavier will be fine, all the pipe is doing is keeping the tines spaced apart. the failures i have seen are normally broken tines or hitches, and i think the operators try really hard to find new ways to brake them, assume you wont as you will have to fix it.

  5. #20
    Join Date
    May 2011
    Location
    Murray Bridge S Aust.
    Age
    69
    Posts
    4,944

    Default

    Quote Originally Posted by Pete O View Post
    easier to make a line of round holes than square ones
    As you'll be getting the tines cut, they can also cut the holes (any shape) in the plate for you, for not much extra. That way they'll all be the same and save you a LOT of extra work.
    Kryn
    To grow old is mandatory, growing up is optional.

  6. #21
    Join Date
    Apr 2018
    Location
    Drouin Vic
    Posts
    386

    Default

    Quote Originally Posted by snapatap View Post
    HT tube is over kill for what you are making, medium wall MS pipe or heavier will be fine, all the pipe is doing is keeping the tines spaced apart. the failures i have seen are normally broken tines or hitches, and i think the operators try really hard to find new ways to brake them, assume you wont as you will have to fix it.
    My thinking with HT tube is to keep the weight down a bit- my usual fab method ends up with something twice as heavy as it needs to be- usually not an issue but I don't want this thing to take up 50% of the lifting capacity of the tractor (unknown) before I pick something up with it. Makes a difference with things like being able to pick up stumps etc to put on the burn pile without having to run the chainsaw through them just to be able to move them.
    I guess an extra few kg in the form of 1.6 meters of 5mm wall 75x75 shs would not be the end of the world, certainly easier for me to find than fancy stuff, but I find it's easy for weight to get out of control.

  7. #22
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    5,043

    Default

    Hi Pete,

    As far as plate is concerned the laser cutters will be able to tell you exactly what the component weight is, since, at least the one I talk to, buys based on sheet weight.
    Best Regards:
    Baron J.

  8. #23
    Join Date
    May 2020
    Location
    Willowbank QLD
    Posts
    194

    Default

    If you are going laser cut most of the price is in setup. Therefore would it be practical to have a piece cut out of the center of some of the larger tines. most of the strength of a tine is in the perimeter. You may be able to save enough weight to offset the need for special metals.

    Steve

  9. #24
    Join Date
    Apr 2018
    Location
    Drouin Vic
    Posts
    386

    Default

    Yes a bunch of holes like an aircraft frame member has occurred to me. I have seen some U.S. commercial ones with lightening holes. Definitely a worthwhile consideration.

    I think one of the big advantages of CAD that I've seen is the ability to calculate weight from the drawings. I must learn to use it one of these days, have never been able to dedicate the time to it yet.
    I've started some sketches and hope to come up with some decent drawings over the next few days.

  10. #25
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    5,043

    Default

    Hi Pete, Guys,

    Download a copy of "Qcad" from Ribbonsoft

    https://www.ribbonsoft.com/en/

    The free download and community edition is very worthwhile, I'm sure that you have seen the drawings that I have posted, all done with Qcad.

    The time spent doing paper drawings could easily be put to use learning how to drive a 2D CAD program.
    Best Regards:
    Baron J.

  11. #26
    Join Date
    Mar 2014
    Location
    South of Adelaide
    Posts
    918

    Default

    Quote Originally Posted by Pete O View Post
    My thinking with HT tube is to keep the weight down a bit- my usual fab method ends up with something twice as heavy as it needs to be- usually not an issue but I don't want this thing to take up 50% of the lifting capacity of the tractor (unknown) before I pick something up with it. Makes a difference with things like being able to pick up stumps etc to put on the burn pile without having to run the chainsaw through them just to be able to move them.
    I guess an extra few kg in the form of 1.6 meters of 5mm wall 75x75 shs would not be the end of the world, certainly easier for me to find than fancy stuff, but I find it's easy for weight to get out of control.
    It think without doing full on structural analysis, the benefits of using ht tube will be minimal, if you are using shs i think 3 or 4mm wall would be suitable.

  12. #27
    Join Date
    Mar 2014
    Location
    South of Adelaide
    Posts
    918

    Default

    Quote Originally Posted by Reidy41 View Post
    If you are going laser cut most of the price is in setup. Therefore would it be practical to have a piece cut out of the center of some of the larger tines. most of the strength of a tine is in the perimeter. You may be able to save enough weight to offset the need for special metals.

    Steve
    lightweight and log grab are mutually exclusive concepts. tines will need to be solid for them to retain enough strength.

  13. #28
    Join Date
    Apr 2018
    Location
    Drouin Vic
    Posts
    386

    Default

    Fellas thanks for all the input on this; I have just been away on a high-country camping trip for the past week and did not want to publish that fact in advance on the internet. I've made some preliminary sketches by the campfire (or under a tarp!) and hope to get a bit more drawn up over the next few days.

  14. #29
    Join Date
    Apr 2018
    Location
    Drouin Vic
    Posts
    386

    Default

    An update- I managed to get my pencil drawings done and Steve is now very kindly converting them to CAD for me and I will then be able to get some quotes on the components. I've decided to go for a single-lid clamshell design very similar to a US made commercial unit that is unfortunately unavailable here. 10mm duraflex for all the tines and 75x75x5 SHS main frame. Mr Singh in Dandenong will be my first port of call for the laser cutting as I can drop in there whilst on shift. I'll most likely start a 'project' thread once there is actual steel. One of my design sketches below.
    IMAG3251[1].jpg

  15. #30
    Join Date
    Sep 2009
    Location
    Newcastle
    Posts
    260

    Default

    I'm keen to hear what it costs

Page 2 of 3 FirstFirst 123 LastLast

Similar Threads

  1. Surface Plate Question
    By simonl in forum METALWORK GENERAL
    Replies: 68
    Last Post: 28th Jul 2018, 08:08 AM
  2. DIY angle plate question
    By Michael G in forum METALWORK GENERAL
    Replies: 10
    Last Post: 9th Feb 2016, 09:13 PM
  3. Laser cut 10mm steel pricing?
    By DoctorWu in forum METALWORK GENERAL
    Replies: 6
    Last Post: 19th Feb 2015, 09:34 PM
  4. Replies: 74
    Last Post: 8th Mar 2013, 08:50 PM
  5. Replies: 21
    Last Post: 19th Jan 2013, 05:54 PM

Posting Permissions

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