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  1. #1
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    How to build a jump in the woods, without powertools.

    Ok, I searched the forums, I even tried google, but no results besides dirt-jumps.

    I want to build a 3 feet high jump, using wood planks, I have a limited selection of tools. The jump will be in the woods, and will be leaning up against a fallen tree (the jump will basically be over the fallen tree)

    What I have:

    Planks, 3 feet long by 1 feet.
    Hammer, nails, sandpaper, saw, showel, rope.

    What I dont have:

    Power tools of any kind.

    ---------------------------

    the wood planks looks like these:




    And the tree i want to build up against is this;



    The tree stands very secure.




    can someone give some tips, or links? Thanks in advance!

    (BTW, im not using that bike to make the jump.)
    Last edited by V.P.; 04-13-2008 at 09:45 AM.

  2. #2
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    If your planks are as thick as they look just lean two up against the fallen tree(red), space them how wide you want the jump. Nail them top to the tree. Then cut other planks the the lenght that the other ones are spaced (brown). Maybe put supports under the two main planks so they dont bend. Asphalt roofing shingles will give you alot of traction once it gets wet.

    Hope that kind of helps. I would personally take parts from the other fallen trees that are there. Two tops that are strong for the main beams. Then a bunch of thick branchs that that can be nailed to the main logs.

    Sorry for my lame pictures.
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  3. #3
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    awesome, thank you for the input! Ill make sure to post some progress pics when i get to it.

  4. #4
    sympathy for society
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    Quote Originally Posted by mtnbikerride

    Hope that kind of helps. I would personally take parts from the other fallen trees that are there. Two tops that are strong for the main beams. Then a bunch of thick branchs that that can be nailed to the main logs.

    Sorry for my lame pictures.
    That last feature looks questionable....... Sticks with shingles laid over top??
    "We can always find excuses if we want to find them, but if we really want to do something, we have to just go."

  5. #5
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    looks questionable but it is solid. The edges have sense be groomed. I talked to the guys who built it and they said they liked the natural look of the rat pak in cle elum, wa so they tried to make a lookalike.
    Take a kid Hunting!

  6. #6
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    Quote Originally Posted by mtnbikerride
    looks questionable but it is solid. The edges have sense be groomed. I talked to the guys who built it and they said they liked the natural look of the rat pak in cle elum, wa so they tried to make a lookalike.
    I've seen similar ones in parks before, and the sticks rot FAST if you leave the bark on. When they rot, they fall out and leave nails exposed. Definitely sub-par construction work, IMO. Also, throwing shingles onto obstacles for traction looks trashy. There are better options. There's some stuff that's paint-on with sand grit in it. Works great, looks like part of the feature, and lasts a long time.

  7. #7
    Don't worry, be happy!
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    what is your native wood? Some native woods look cool, but rot pretty fast.
    I agree the shingles look bad. There are lots of other alternative to add traction.

  8. #8
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    Does it matter what it really looks like? Its still fun to ride. I agree the stick probbly were not the best material the builders could have used, too wet in western washington, they carried wood in for the long ladder on top though. How far would you have to carry the material, that would be a major factor for me? If it more then a half I would just cut it out of the way with the saw, wood gets heavy.
    Take a kid Hunting!

  9. #9
    Im a huck bunny
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    Shady

    I would not lean my bike on the last feature. No Offence.
    Ride Monkey SUCKS

    [SIZE="5"]Transition [/SIZE]

  10. #10
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    How about picking up 2 pressure treated 4x4's x 8 foot or 10 foot long and cut another 2 mid length posts to go between the first tread board and the last and use your planks with 1 1/2 inch gaps...........or find 2 more 6" diameter dead falls and cut them 10 foot long or what ever length works for your height and speeed and landing zone and use those for your beams and plank them?

    Check out the new Bike mag. issue for the basics of all of this stuff. Check out the IMBA books, too..and check out what the BC guys are doing on their north shore forum. They have lots of tech/build stuff there. Build it strong so it lasts and you don't bust through it at full speed and kill yourself and your buddies or a stranger.
    IF YOU CAN READ THIS, YOU'RE NOT RIDING (or building)!

  11. #11
    shred
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    if u use your imagination you can build some rad obstacles with nothing. what i had to to is look around my neighnorhood for plywood and stuff and and just build stuff. since i have no actual trails within like 50 miles

  12. #12
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    [SIZE="6"]UPDATE 1[/SIZE]

    So ive begun the project : ) here are some pics;


    I bought the wood, and bagged it into the backpack, and from there on I had to carry it into the woods...ough, what a walk : /





    So here is my wood and tools, just scattered around as I try to figure out how to tackle this (remember, this is my first build);





    I have to somehow support the ramp, so that it does not break in the middle, this is my solution, notice the long nails to stabilized the upper lumber piece





    So here is my first draft of the actual ramp/jump, nothing at this point is nailed down or anything, im still just positioning things before I start the real work;






    I didnt manage more that day, I ran low on wood, and had to buy some more, ill get back soon tho ; )



    ,

  13. #13
    Ride da mOOn Moderator
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    Wink

    Your idea looks ok but remember the tree is supported by all the smaller brances and will eventually drop as you ride it. I don't know how fast you intend to hit it!

    Just some observations

    Good Luck!

  14. #14
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    Quote Originally Posted by NEPMTBA
    Your idea looks ok but remember the tree is supported by all the smaller brances and will eventually drop as you ride it. I don't know how fast you intend to hit it!

    Just some observations

    Good Luck!

    Yearh, I might have to support the tree with some wood.

  15. #15
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    You should use a cordless drill and screws instead of nails.

    last longer without pulling out.

  16. #16
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    Also remember that your stringers, the long "beams" under the the planks you ride on. want to be vertical not flat when you build these ladders. It's 3 times stronger when you turn the stringers vertical versus laying them flat using the same wood members. Pressure treated wood will last much longer that untreated wood and it's less slippery too!
    IF YOU CAN READ THIS, YOU'RE NOT RIDING (or building)!

  17. #17
    Ride da mOOn Moderator
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    Good job!

    Quote Originally Posted by General Havoc
    You should use a cordless drill and screws instead of nails.

    last longer without pulling out.
    Hum... Viraga commercial?


  18. #18
    Builder of Trails
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    Nice start.

    As has been stated, remove the bark on the tree at least where the ramp connects, if not on the whole trunk.

    Also, as stated before, standing the stringers up will ensure a much stronger structure.

    And since you're using lumber, you can cut cross hatches on the planks instead of tacking on roofing shingles. It's a much better look and will last much longer, too.

    D

  19. #19
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    Your center support is a good idea but:
    1. the long nails helping balance the top log seem dangerous and very insecure.
    2. consider getting a third log for the support. Place two bottom logs parallel to the trail and cross the support log over the bottom two logs. Notch for the top log and your support won't fall over.

    I don't think shingles will look out of place on this machined lumber jump.

    Consider some sort of transition for the landing. Sure if you have enough travel, you can suck up the landing but regardless, landing flat is not fun.
    Oh sh!+ just force upgraded to cat1. Now what?
    Best thing about an ultra marathon? I just get to ride my bike for X hours!

  20. #20
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    [size="6"]UPDATE #2[/size]

    So im almost done with the ramp/jump, ill definately look into making it more stable, but the way it stands right now, its very solid! It does flex a little, but only when I jump on it. otherwise it does not move.

    Ive been thinking about a transition for the landing, but I haven't decided yet.


    So here she is, 2.5 meters long, and 90 centimeters high;




    I still got some finetunig to do, so ill post some more pics when I got those things sorted out. Thank for all the input!!

    .

  21. #21
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    Or....use 3 logs stacked teepee style and use some metal banding with holes in it and wrap all 3 logs and nail the banding using 2 hammers and long nails, 1 to tighten the banding with the claw and a nail and the other to nail the nails!

    If you have a hatchet or axe, you can cut a big log section and notch the top to hold the underside of your main support trunk by sliding it in under from the landing side and dig it in a little to wedge it and even leave it on an angle out towards the LZ to resist the forces of you hitting the jump at warp speed.
    IF YOU CAN READ THIS, YOU'RE NOT RIDING (or building)!

  22. #22
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    Looks good - the only thing you did "wrong" is that the stringers (long pieces) need to be turned upright (already mentioned) - BUT with the center support, I'm sure it'll work as it is. Nice effort!

  23. #23
    Human Power LLC
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    is it secured to the center support?

  24. #24
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    Quote Originally Posted by Aktion
    is it secured to the center support?

    yes it is, with 6 long nails.

  25. #25
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    Use dirt and a shovel.

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