Portaledge Discussion: Delta 2p vs Full Double D4

John designed multiple files for various bullet joiner sizes. This likely explains it. 

Erik Jwrote:

Pardon the thread drift... I'm looking at building a D4 and am somewhat confused at Johns notes. Particularly, at the moment at least, how the frame pieces fit together. 

The diameters of the tubing relative to the "bullet" dimensions dont match - I'm taking measurements of the bullet from the step file on the website. Am I correct in that the orange sleeve goes over the male end of the bullet, and the pink tube goes into the female end?

If someone has one of these things kicking around and doesn't mind taking some measurements or pictures (OD of tubes, OD of bullet, length of bullet )I'd be forever grateful. Thx

There's too much going on for this to be done via the brain. Best way is to buy joiners, buy tubes, figure it out.

As much as John advocated for D4 to be as DIY-able as A5 ledges, they are more complicated. The problem is, you kind of need experience bending the tubes to understand how it works. Also, I am fairly sure after making several models and seeing other brands that what happens is you build a frame, and that is YOUR frame. Depending on how you interpret the measurements you'll be in/out an inch or two, which is why John does not really include precise bed dimensions. Unlike the A5 where building a frame is pretty easy, you are compounding dimensions with D4 joiners and bends. The bed is going to be slightly different than the basic drawings he provides, and he does not include all the parts like on the A5 drawings. You can literally make an A5 start to finish if you follow the instructions. D4 is more like "but does this affect X" and you will no doubt forget the center seam in measurements. If you didn't forget, that's because you probably didn't get to the point of accepting multiple failures as a path forward.

Here's the problem you are describing: bent corners go INSIDE the joiners, long tubes go OUTSIDE.
Tubes are 1.125/1.375 and both .058 wall. this gives you the 0.009+- tolerance for a slip fit for the inside and outside the joiner, and space for epoxy. These are "telescopic" and tubes sold as .058 wall are expected to follow a more specific dimmension. I would know, initially I ordered some tubes from a supplier and I figured I could make them work for an A5 frame somehow at 1.125" .062 wall and the dimms were all over the place. 0.058 wall REQUIRES that they are telescopic.
1" tube goes in the 1.125" tube

That being said, if you don't have half a frame or more in the garbage for this project I would be extremely impressed. 

This is excellent thank you!

High Mountain Gearwrote:

It also depends on who made it, as I think some makers of the Delta 2P have different dimensions.

Another note, I would be cautious about this central connection as its sewn in a way that should be fine, but if you had it tensioned and “gave it what for” it might rip out. As I read his notes it appeared he was in between a fin and that tab, and it does make more sense with the tab but its not nearly as durable as a fin. 

I thought I would update my comment about sharing the d42p. After sharing it with my shorter partner for 10 nights between 2 ascents, we fit pretty well on it. It was still a bit tight, by with heads on opposite sides and him in fetal position, we slept well. However on the last night we had it on tangerine trip, a giant tear formed by kneeling too close to the "spreader". In hindsight I may have had it too tense by connecting it with a single alpine draw. I've been quite happy with the ledge so far and may do another ascent with a patch on it and not sharing it, but this was disappointing. I have used it ~70 nights over 2 years, is that how long it should last? I'm reaching out to Barry at Durango Sewing to see what can be done, but interested in quotes from others who could replace the bed sheet.

Bailey Moorewrote:

I thought I would update my comment about sharing the d42p. After sharing it with my shorter partner for 10 nights between 2 ascents, we fit pretty well on it. It was still a bit tight, by with heads on opposite sides and him in fetal position, we slept well. However on the last night we had it on tangerine trip, a giant tear formed by kneeling too close to the "spreader". In hindsight I may have had it too tense by connecting it with a single alpine draw. I've been quite happy with the ledge so far and may do another ascent with a patch on it and not sharing it, but this was disappointing. I have used it ~70 nights over 2 years, is that how long it should last? I'm reaching out to Barry at Durango Sewing to see what can be done, but interested in quotes from others who could replace the bed sheet.

Skot at Skotswallgear is likely going to be able to assist with the bedding. His work is solid and representative of his experience as an actual bigwall climber in terms of the solutions and mitigations that he can suggest based upon how you bigwall and the state of your ledge. He replaced the bedding on my orig Delta2p from Middendorf so he's aware of and has experience with those dimensions - and specifically has experience beefing up my center divider tab as well. Additionally, Skot is probably going to be faster and more consistent in responding and communication than my experience with Durango sewing has shown. (Skot's on El Cap right now so he will be a little slower than normal in responding until he gets down)

70 nights over 2 years is a lot of use compared to most bigwall climbers using their ledges, but the real defining issue is how one is utilizing the ledge during those 70 nights. Flagging and using it as a belay ledge obviously does more damage over time than packing it up at the beginning of the day. Using the divider webbing anytime you're not actively laying down and sleeping is going to introduce additional stress on the fabric, especially when standing without supporting some of the standing weight with a tether or standing partly on the frame. 

Thanks Kevin, I'll be sure to reach out to him once he gets down from Disorderly.