Adding a foot box to a PaddyMade Hotham

[Moondog55]

Well the Sleeping bag arrived in the post this morning and I'm really surprised by the quality and condition
It needs a wash of course but it is one of the early ripstop shells, with the old log patch and no serial number or washing instructions sewn in and made with "First quality Steam -sterilised SuperDown" so I'm thinking around 1980?
Anyway it is almost long enough but I will be more comfortable with a shaped box foot in this and I want to add one
Round as that will conform to the Bivvy and outer bag it will be used with, that is the US Army bivvy and patrol bag are OK for summer as-is, this will do in winter for car camping when combined.
Simon sells down in 42 gram increments; will 42 grams of down be far too much in a footbox only 300mm in diameter?
The alternative would be a few layers on synthetic insulation but Simon is out of stock and what I have is earmarked for my half-bag addition
Will be selling or giving away my old car-camping bag; this one is so much better

[Orion]

Just for reference, I used about 13g of 900 fill down in a foot box end that was about 30cm diameter. It was a little overstuffed since I hate having cold feet. That was just for the very end, not the connecting sides of the box, if you know what I mean. The longest horizontal tubes in the quilt contained 26g of 900 fill down.

My quilt was intended to only be good to about 0°C.

[Moondog55]

13g is about half an ounce and that is about what I was thinking would be enough. I did have the thought [ I also hate cold feet] that I could make it with Climasheild on the outside and down as the inner getting the best of both worlds and I just found a scrap of the Reflective wadding that I used to stiffen up the footbox on my overbag and I can may use that as well

http://www.spotlightstores.com/by-the-m ... BP80301570
How many channels did you use in your footbox Orion? I was going to use a 25mm baffle but if I use down plus synthetic I may be able to get away with tuck stitching sewn through

[Orion]

There are rough rules of thumb you can look up for calculating the loft needed for a particular temperature rating. The real loft required depends on your metabolism, which in turn depends on age, gender and also individually. But once you decide on a loft thickness you can calculate the down required pretty easily. For a circular foot box it would simply be pi * radius squared * loft / fill power. Usually a fudge factor of at least 10% is included to account for the effects of age and humidity on the down.

For my foot box: (6 inches)^2 * 3.14 * (2.5 inches) / (900 cubic inches/ounce) = 0.31 ounces = 9g.
As you can see, 13g was an overstuff.

I used only two sections for the foot box in my quilt. Here is a photo of half of it:

[Moondog55]

Well I made a start
Footbox will be bigger than the overbag size so I'll go for a space filler cut with all pieces the same size. Photos of the Hotham beside my J&H Ultra, both bags the same nominal -5C rating; one at 1600g the Ultra at 900grams

[Moondog55]

Because the shell is in such good condition I'm wondering if I should rip the seam and stuff another 100g of down in there while I'm working on it, or at least in the top section; Simon sells in 42 g lots how much difference would that 42 G make?

[Moondog55]

Maybe there is an even easier way to get this done
Hem it and put a draw cord in the bottom, it is the Long version after all
Quick consultation with the Boss and that's what we will do and I'll order two lots of down from Simon and top it up
This allows me to walk around wearing the sleeping bag
But I am interested in how much difference it will make

[Moondog55]

I've come up against a small problem
I've never considered my self a bog bloke even tho I take XL in clothes
Cecile measured me last night and I go 61 inches [ 154cm] around the torso with my arms flat against my chest. Can someone suggest the easiest way to add a wedge into this Hotham? I need to add 155mm to it's internal girth so I can fit in
I'd never tried a Hotham for size before and had not realised how skinny they are

[stry]

I've come up against a small problem
I've never considered my self a bog bloke even tho I take XL in clothes
Cecile measured me last night and I go 61 inches [ 154cm] around the torso with my arms flat against my chest. Can someone suggest the easiest way to add a wedge into this Hotham? I need to add 155mm to it's internal girth so I can fit in
I'd never tried a Hotham for size before and had not realised how skinny they are

People were smaller then - well most of them were

OP provides an optional zip in wedge to expand some of their bags. If you could have a look at one of those, you may get some ideas.

[neilmny]

That looks like a very doable idea stry.

[Moondog55]

Just had a look at the "Wedge idea" looks easy enough
I think the hardest part will be the unpicking of the zipper

[neilmny]

Just had a look at the "Wedge idea" looks easy enough
I think the hardest part will be the unpicking of the zipper

It might be possible to not unpick the zipper if you can get a matching zipper.
Then make your wedge with a bit extra length and width to act as a baffle and sew half the new zip one side of the wedge and half the other matching up with the existing zip halves.
The new zip halves would be "offset" around the the outside of the wedge towards one another so that when fitted the inside of the wedge would be bigger than the wedge formed by the zips.
Hope that makes sense MD.

[Moondog55]

I thought about that but as this needs to be permanent I think I'll do it the hard way, sew the zipper on straight and shape the other side of the wedge. Sort of half coffin shape

[Moondog55]

Took me a few days but I've added a drawstring to the foot because that was easiest to do
I closed up the bottom half of the zipper and I added a 200mm wide wedge at the shoulders and added a non stick webbing tape under the zipper to stop it catching
Now I can actually get my arms and shoulders inside the bag
I was a bit of a fiddle but I'm sure I'll do better next time