BigWalls Forum

Big Walls => A5/D4 Open Source Designs => PORTALEDGE DIY HOMEBUILD INFO => Topic started by: Jasper.Younger on September 25, 2020, 03:48:31 AM

Title: Jaspers "experimental" Ledge
Post by: Jasper.Younger on September 25, 2020, 03:48:31 AM
On wednesday I received a ledge frame from Tasmania which was cool. After finding out it was long enough I traced the internal shape onto some old sail track sign banner I picked up out of the bin at work earlier in the year, I think this will be a pretty good fabric to learn on as feels about as tough as 1000d cordura and it laminated on one side so it doesn't fray much on the edges.

After tracing the basic shape I added about 150mm border around that shape to give me plenty of fabric to work with after I've wrapped it around the tubes. Most of the information about the measuring and making process will be uploaded in screenshots taken from my Instagram story.

Being pretty heavy I decided to go for 3 rows of stitching where the fabric joins itself after wrapping the tube I think in future or with a different fabric I'd use a thin 3M VHB tape to make the initial join and then sew through or next to the bonded part.
So my progress so far is just having the four side sleeves sewn.

The next step will making the bed tensioners at either end, I have pretty average plastic webbing buckles like what you might find on a backpack shoulder strap adjuster. While that's all I have I'll try and use them but leave myself the option to upgrade to metal later. next time I'll be making some triangular patches and trying to join webbing to fabric in a strong enough manner.
Title: Re: Jaspers "experimental" Ledge
Post by: Jasper.Younger on September 25, 2020, 04:14:37 AM
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Title: Re: Jaspers "experimental" Ledge
Post by: Jasper.Younger on September 25, 2020, 04:17:51 AM
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Title: Re: Jaspers "experimental" Ledge
Post by: Jasper.Younger on September 25, 2020, 08:17:37 PM
I like the simplicity of a continuous loop of bungee but I feel there’s a bit wasted between the joins

What size hole would be acceptable to drill into the sides of ledge tubes😳? 1mm, 1.75mm maybe even 2?

I’ve got an idea that would be pretty annoying to assemble but could save a bit of weight in shock cord...
Title: Re: Jaspers "experimental" Ledge
Post by: Deuce on September 26, 2020, 12:53:33 AM
I don't recommend drilling any holes in the tubing.  Just use a continuous piece of 8mm shockcord, tied with a Grapevine knot.
Title: Re: Jaspers "experimental" Ledge
Post by: Jasper.Younger on October 27, 2020, 03:24:28 AM
I got the chance to play with amsteel finally today 1/8" or 3mm.

The plan was always to use it as the adjustable suspension, it went pretty well but I've run out of the stuff.  I used more than expected on the splices and the continuous loop and I burnt through a bunch just making mistakes, I would consider a hot knife is essential if I was to do it again.

It's only 7.4 grams per metre and I used roughly 14 so far.   The lines go from buried eye splices at the joiners up to whoopies at the top and then the will come together in a continuous loop. Both the long sides will come together at each end of a daisy chain of continuous loops and I'll be able to adjust the level of the ledge from free hanging to slaby by just shifting loops (I feel that's a poor explanation but I'll give a photo example when I have it working).

I'm happy with how it's going so far and the relative simplicity of it. Although you can't adjust the ledge while loading it because of the whoopie slings I feel the weight savings and lower parts count is nice.
Title: Re: Jaspers "experimental" Ledge
Post by: Jasper.Younger on October 27, 2020, 03:26:34 AM
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Title: Re: Jaspers "experimental" Ledge
Post by: Deuce on October 27, 2020, 09:31:39 PM
Interesting idea for suspension, but recommend using a quick link to connect with my D4 Joiners “with eye”.   Old cause wear.  Or use a stealth.  Might be ideal for super ultralight ledge design.

People have also mentioned using “soft shackles”. 

I like quick links best (make sure not to load unless fully closed).
Title: Re: Jaspers "experimental" Ledge
Post by: BuffaloBrad on January 10, 2021, 05:50:59 PM
I too have considered using "whoopie slings" for suspension straps. I have used these on many highlines and climbing rigs.

To quote Jasper
Quote
you can't adjust the ledge while loading it because of the whoopie slings
Once loaded a whoopie sling is NOT adjustable.

I do like the idea but the lack in ease of adjusting once weighted is a major con, more thought is required to make this system ergonomically friendly.