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  1. #1
    Senior Member cameronjreed's Avatar
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    Cool Super Easy Cat Cuts

    I have been building my cat tarp and started a bridge hammock (in other words I have been busy making cat cuts)
    I have found a very easy and efficient way to cut great looking catenary curves....
    First, it is important to not that I have a shop with a sheet rock wall.

    Step 1:
    To make the cat curve I started by measuring up 65" from the floor in the shop in two different locations on the same wall. I then use a chalkline to mark a level line between these points.

    Step 2:
    Next I use modelling pins (you could use thumb tacks) to hang the factory edge of the fabric along the chalkline mark.

    Step 3:
    At this point if my fabric is not cut to length I do this by measuring to the desired length and then use a plumb bob to ensure a straight line (gravity please don't ever fail me ) I make several dots along the line and then remove the plumb bob and use a ruler or straight edge to connect the dots.

    Step 4:
    I then find the middle of the fabric. I place a mark on the wall where the mid point is.
    At the mid-point I use a measuring tape to determine the maximum amount of curve I want (6" or 10" etc, etc) I make a mark on the fabric at this point.

    Step 5:
    I then use a piece of string (usually the chalk line) and pin one end of the string to the end of the fabric. Then do the same to the other end of the fabric, but I make sure that the string touches the mark on the fabric I made at the mid-point.

    Step 6:
    With the string still in place I carefully (without moving the string) make several tiny dots on the fabric along the string with a sharpie or other marking device.

    Step 7:

    Remove the string.

    Step 8:
    Connect the dots using a ruler or straight edge.

    VILOA perfect cat cut pattern.

    To ease the cutting process I leave the fabric pinned to the wall while I use a soldering iron to cut and fuse the edges of the fabric.

    Warning:
    Be careful using a soldering iron for anything other than its intended purpose.
    Also...Using a soldering iron on sheet rock (or plaster walls) will leave permanent marks.
    "Life is to be enjoyed, not just endured"

  2. #2
    GrizzlyAdams's Avatar
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    80% of the time I spend sewing is in making double roll hems (or if I'm extravagant, putting on bias tape).

    If you cut and and fuse fabric with a tool designed for this, it is necessary to hem the edge?

    thanks

    Grizz ( who is off now to spend another hour hemming )

  3. #3
    Senior Member cameronjreed's Avatar
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    Quote Originally Posted by GrizzlyAdams View Post
    80% of the time I spend sewing is in making double roll hems (or if I'm extravagant, putting on bias tape).

    If you cut and and fuse fabric with a tool designed for this, it is necessary to hem the edge?

    thanks

    Grizz ( who is off now to spend another hour hemming )
    Unfortunately it is still necessary to hem or bias the edges. The fusing is simply to keep the edges from fraying whilst working with the fabric. It it is sil that you are working with (which does not fray) the solder gun still cuts through it like butter and leave a nice smooth cut.
    "Life is to be enjoyed, not just endured"

  4. #4
    Senior Member TeeDee's Avatar
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    Grizz - did you experiment with a symmetrical arc on the Bridge?

    If so have you been able to compare to asymmetrical arc?

    This method could be modified to yield an asymmetrical curve with the mid-point shifted toward the head end.

    The original was asymmetrical, but I don't really know how necessary that is if at all or how differing spreader bar lengths at head and foot ends affect the hang with a symmetrical curve.

    If I remember correctly, your customized curve was asymmetrical also.

  5. #5
    Quote Originally Posted by cameronjreed View Post
    Step 1:
    To make the cat curve I started by measuring up 65" from the floor in the shop in two different locations on the same wall. I then use a chalkline to mark a level line between these points.
    hope your floor's level to begin with

  6. #6
    Quote Originally Posted by cameronjreed View Post
    At the mid-point I use a measuring tape to determine the maximum amount of curve I want (6" or 10" etc, etc) I make a mark on the fabric at this point.

    Step 5:
    I then use a piece of string (usually the chalk line) and pin one end of the string to the end of the fabric. Then do the same to the other end of the fabric, but I make sure that the string touches the mark on the fabric I made at the mid-point.

    Step 6:
    With the string still in place I carefully (without moving the string) make several tiny dots on the fabric along the string with a sharpie or other marking device.

    Step 7:

    Remove the string.

    Step 8:
    Connect the dots using a ruler or straight edge.

    VILOA perfect cat cut pattern.

    To ease the cutting process I leave the fabric pinned to the wall while I use a soldering iron to cut and fuse the edges of the fabric.

    Warning:
    Be careful using a soldering iron for anything other than its intended purpose.
    Also...Using a soldering iron on sheet rock (or plaster walls) will leave permanent marks.

    how does this create one curve rather than 2 straight lines running form the ends to the center mark??? did i miss something?

    that actually seems like a good idea though, getting down on your hands and knees on the floor is a pain, and the fabric would probably spread better, probably wouldn't work as well for trying to trace a pattern with though.

    did the fabric lay flat and still against the wall? if you mounted a cutting board on the wall, you could just tilt the bottom out a bit.

    Grizz, a couple of the online shops sell a "hot knife" it's just a soldering iron with a round blade tip, (not sharp) you might be able to find something similar in a soldering iron kit. i cut fabric almost exclusivly with one now, the back of a peice of white 4x8 tileboard from home depot works great. it's about 3/16" or so thick, looks like dry erase board on one side and brown on the back. i think it's wood product, but not like particle board, the compressed wood is in tiny fiber form so it is really consistent which is what makes it work well)

  7. #7
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    TeeDee -- i wanted to see what all the hoopla was about concerning this bridge hammock thing, so last night i made one out of a piece of fabric i had laying around using the directions on that aussie sailing site as a guide. it is 7' long, 56" wide at the ends, and has a symmetrical 12" cat cut along the sides. i double rolled the hem around the perimeter and sewed 1" wide poly webbing loops on the corners, overlapping the body approximately 3" along the long sides. i wasn't sure if that would be sufficient, but so far so good. as a temporary measure i used a pair of square decking balusters as spreader bars. i drilled several holes through them and used some spare hardware to make a way of easily attaching them to the biners that i had put through the loops at the corners of the fabric. this made changing the length of the bars a 30-second operation, so i was able to try several lengths in a very short time for comparison. i started with 30" and went up to 38" in two inch increments. i also tried it wider at the head end in various combinations. after trying every possible combination several times, i came to the conclusion that although i could feel a slight difference in shoulder squeeze, it was not enough of a difference to get excited about. the trade off for a longer bar length was a corresponding loss of stability. again, not dramatic, but noticeable. i suspect that changing the cat cut will make much more of a difference in how the hammock hangs, but of course trying different cuts is not nearly as easy. i also spent some time last night hacking up an old kelty synthetic bag to make a 3" thick underquilt for this new addition to the hammock collection. (that IS what this forum is all about isn't it... hammock collecting?) i guess that is anther thread so i will just say that i hope to do some backyard testing tonight and maybe post a report tomorrow.

    i'm looking forward to your detailed bridge hammock article and pictures, as are many others here. not sure what the delay is, but as they say, patience is a virtue. thanks to all for sharing your ideas and experiences.

    -20



  8. #8
    I have a shop with a sheet rock wall.
    Not to drift any...but what do you do in this shop? I'd like to get a look at a woodworking shop if you have pictures.
    As far as super easy cat cuts? I had my length, my depth and then made my best-guess as to the curve itself. I figured my lack of sewing ability would negate any attempt at perfection in the layout process.

    TWS

  9. #9
    GrizzlyAdams's Avatar
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    Quote Originally Posted by TeeDee View Post
    Grizz - did you experiment with a symmetrical arc on the Bridge?

    If so have you been able to compare to asymmetrical arc?

    This method could be modified to yield an asymmetrical curve with the mid-point shifted toward the head end.

    The original was asymmetrical, but I don't really know how necessary that is if at all or how differing spreader bar lengths at head and foot ends affect the hang with a symmetrical curve.

    If I remember correctly, your customized curve was asymmetrical also.
    I've tried a number of things, for the most part doesn't seem to make a difference in the lay. Warbonnetguy opined, and I came to agree, that the main impact of the curve is to keep the center from dropping too far, and there are number of ways of skinning that cat.

    My most recent bridge uses symmetric cuts, 6" deep. I'm not inclined at this point to alter that formula.

    Grizz

  10. #10
    GrizzlyAdams's Avatar
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    Quote Originally Posted by cameronjreed View Post
    Unfortunately it is still necessary to hem or bias the edges. The fusing is simply to keep the edges from fraying whilst working with the fabric. It it is sil that you are working with (which does not fray) the solder gun still cuts through it like butter and leave a nice smooth cut.
    well that's a pity.

    I can definitely see that it's worthwhile to keep the ends from fraying.

    thanks

    Grizz

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