(no subject)
At the Krae Glas craft hall it became obvious that the sunshade project needs a set of standard dimensions to make a standard krae glas sunshade. And we need them written before our next sewing day. I know what was proposed, but would like to tidy a few details.
The bits that need to be the same for everyone (the standard template), in order of us to be able to chain sunshades together are:
-distance from front poles to back poles
-distance from back poles to ground
-height of poles
-attachments for poles and pegs in the 4 corners and middle sides of a to be deteremined specified minimum dimension (so poles and pegs can be shared)
Variations can be made while maintaining the standard template, so all sunshades can work together:
-dags on front edge, be they sewn on or tied to sewn on tabs
-wider sunshades are fine (although will need more poles)
-different widths of canvas can be used (eg later batches)
-extra poles across the front and back is fine
-painted or decorated canvas and/or poles
-tabs for tying on walls or banners
-poles can be single piece or slot together
-longer canvas can be used as long as the extra can be tucked under and the sunshade pegged at the same place as others on occasion
-wooden railings can be added at front
The proposed design was to make the canvas twice as long as this batches width (after a standard hem - we need to measure and specify that precidely), with half that length forming the roof and the other half forming the slant to the ground. Proposed was two models of poles: either four 2.1m poles or two 2.1m poles and two 1.8m. We stood with the canvas held up by people playing poles of 2.1 and 1.8m height and most people were able to stand comfortably there. The space would be fine for a family, but crowded for more than 3 adults relaxing on chairs in inclement weather, assuming walls or an adjacent sunshade to protect the sides. Please note 1.8m and 2.1m are approximations - we should investigate what cut lengths are easily available in approximately this size and adopt that as a standard
Discussed (by me at least) was simplicity vs efficiency.
Simplicity:
- Having a rectangle a 2:1 square is simple, and if unelaborated cannot be put up the wrong way around.
- Having poles the same height means you always have the right pole in the same spot
- Having poles the same height means it is easier to measure and cut poles initially
- Less poles is less trouble
- 2.1m is the height of the poles in the readily available basic soldiers tent design which many people showed intered in (although several seemed likely to modify the height), allowing for emergency pole substitution or a matched set of multiuse poles as long as they are of tent sturdiness.
Efficiency:
- Having a slanted roof should shed water better, and to the back instead of over people/at the front making mud to walk in
- As most of the slanted section of the roof is not very useable except for storage, is a shorter canvas preferable? (or does it allow the front to be dropped easier to keep things relatively dry overnight?)
- Or does a shorter canvas mean less support for the roof as the vectors are wrong.
- More poles is taughter canvas, is better water shedding ability
- Will taller poles let more weather blow in?
And the real world:
- These will be used by people who have varying knowledge of tent pitching. Since an inefficiently pitched sunshade is still
sufficiently effective under most conditions, and in fact will save net time in all bar a bad storm, let's assume many people never learn tent mechanics.
- But they won't be group property, so it is likely that the owners will quickly learn to tell front from back, taller poles from shorter, etc.
- Canvas which is poorly pitched or poorly maintained, or just old, will sag. Let's assume this will occur when we design the sunshades
- When less poles are used, there will be more bits between poles with bigger sags.
- So should we make the poles taller assuming that the canvas will sag? Is 30cm a resonable estimate of sag for wet canvas across a 2.6m span?
- I'm assuming 2.1m and 1.8m poles are about equally difficult to transport (weather as single strut or segmented)
Advice is sought, especially by those with knowledge of sunshade construction and workings:
-what hasn't been considered?
-how well do equal poles work and other assumptions above?
-are these dimensions sensible? (is 2.1m too tall for a sunshade?)
-Is there anything wildly inauthentic about such a design we can avoid?
-should we go with 4 poles the same or 2 heights of poles?