# Thread: Odd shaped synthetic UQ always too loose or tight

1. mr tickle,

Thanks for sharing your observations and experiments. This is a valuable thread. It may save others a lot of work, and it might also inspire someone to come up with yet another solution.

You asked whether you'd feel the bungee loops under you, and I don't know, because mine are sewn to the bottom layer of an insulated hammock, not to the hammock bed itself. Also, your idea of velcro tabs might work, but you'd lose the elasticity of the bungees. Hammocks stretch and change shape as we move in them, so locating places to attach a supplementary UQ will always be approximations. The stretch of the bungees compensates for minor misalignments. I experimented with magnets to hold the layers together and found that even very strong magnets have far less shear strength than peel strength, so they slide apart. (I'm still working on a solution that will compensate for that.)

Lastly, FWIW, here's my method of making an underquilt that fits a hammock because it's the same shape as the hammock when someone is lying in it. (Warning #1! This is labor-intensive verging on obsessive.) 1. Have someone the right size lie in the hammock. 2. Draw triangles on the bottom of the hammock, covering the entire surface. 3. Measure each side of each triangle. 4. Use the measurements to make tyvek or paper triangles. 5. Tape the triangles together in groups, so each group forms a flat pattern piece. 6. Use the pattern pieces to cut out fabric pieces. (Warning #2! So far it has just been tedious; now it gets tricky.) 7. Sew insulation to the fabric pieces. 8. Assemble the pieces to form the curved top layer of the UQ. 9. Scale up the pattern to use for the bottom layer of the UQ. (Trickier still.) 10. Attach to hammock. (Tricky, trick, tricky .... You get the picture.) Don't do this, even though it works.

2. WV, good point on needing flexibilty, i completely overlooked that and will keep that in mind as i progress to a solution.

Wow, the triangle method is indeed labour intensive, that really is an exceptional idea, i like it. Beyond my ability at present, but certainly something to toy around with as i become more confident on a machine and may perhaps become a pipeline project. Is this something you are using? I'm curious how all the thread work has effected weight and how this has performed for you?

Perhaps i can return the favour a little here, i have attached a photo regarding the magnets with poor choices of words included!

Magnet Fastening.png

Of course, the upper magnet would sit flush with the tube top pulling the baric between, the tube acting as a side wall to prevent shear. The magnet could also be coated to protect the fabric. I forgot to write that on the diagram but no doubt you figured that anyway. Of course, it is not flexible though, useful for the odd fixing perhaps. Hope it helps some

3. I am about to embark on making a UQ out of Climashield 5.0 oz per sq yd. I got it and my material this week. I am going to do a diff cut. Like you I think I have a general idea but really I have no clue what I am doing. I figure I will just jump in and see how it goes.

I used the spread sheet found in this thread to get a general idea of what the Diff cut should be. https://www.hammockforums.net/forum/...-UQ-Calculator (look at post #36 for the latest spreadsheet. From that I decided I wanted a 48 inch wide quilt. I used a thickness of .33 inches for the height of the baffle. With that it came out with a outside shell of 56" and the inside shell of 50". This allows 1 inch on each side for seem allowance I split the difference for the climashield and I will cut it to 53".

For the inside shell I am going to do one 2" dart in the middle of head and foot end. For the outside shell I am going to do 2 darts of 4" each. I am going to place them about 1/3 and 2/3 of the way along the head and foot end. The Climashield I was going to do 2 darts of 2.5" each. Once again at about 1/3 and 2/3 of the way along the head and foot end. I don't know if this is right but I came up with it based on the plans found on the diy gear Supply web site. http://diygearsupply.com/wp-content/...xUQ-lowres.jpg I also would look at the following link https://www.hammockforums.net/forum/...Underquilt-DIY

To sew it I am going to sew it similar to as shown in post #24 of this thread https://www.hammockforums.net/forum/...st-night/page2
I am going to lay it out that way but only sew the long sides then flip it so the outside is out and the inside is inside. I will finish it by sewing gross grain on the head and foot end.

I tried to find one good tread that walks through doing a synthetic climashield uq with a diff cut but couldn't find one. Maybe I don't know where to look.

I figure that if it fails then I will chalk it up to education.

4. Hey mate,cheers for the info, i decided to make a thread for the new project quilt here:

https://www.hammockforums.net/forum/...h-3-4-diff-cut

That UQ calculator is for a box section quilt, a different kind of differential quilt suitable for loose fill not sheet insulation. I know i have mentioned in this thread i am considering that option, but i thought i should mention it as this reply was in relation to climashield and i don't think it is applicable for such use. If you use something like loose fill primaloft one it will be useful, just not climashield afaik. Sheet materials and baffles don't appear to mix, although i may be wrong the research i have done has suggested this. Also, the temperature rating to loft ratio will not be the same for climashield so the baffle calcs are probably no good either. OFC i could be wrong, It is ofc handy for a box section, i was toying around with it last night and it is great so thanks for the link.

I will admit i am becoming quite torn whether to make a synthetic loose fill quilt or sheet insulation.

I indeed was thinking something along the lines of this pattern, but with a couple on the sides too (long story short my other thread makes me want them on the sides as a safeguard, my fear may be misplaced). My concern however is that the Insultex works by creating an air gap between layers, the size of that gap tends to look quite large on an IX quilt. So, if i layer synthetics in such a manner and end up with gaps between them i may as well just have used one sheet of insulation. I don't mind the outer shell hanging low, but i want my inulation sheets snug together. I figure this falls down to mathematics opposed to trial and error, so, unless someone has a 'known' working solution i will look into what the formula should be over the rest of the weekend to avoid waste. I definitely used to have a link a site that gave exact information for darting 2.5oz climashield, but it is now a dead link.

My apologies i should have been more specific in my other post in that other thread, but at the time i was only kinda talking out loud and semi-ranting.

So, where i am finding myself is looking for confirmation of how to get the diff cut, yet keep the insulation layers snug; also, opinions on whether a box section loose fill (primaloft) quilt is worth the extra work! My plan over today/tomorrow is to make a mock up out of a fleece throw and see where the cuts would need to be for the general shape of the inner shell.

It is times like this i wish i lived in the states, i could just buy a good synthetic or a self fill box section shell for a little more than it costs to make. *envy*

I would also be interested to see photo's of where you place your darts and how it turns out if you get the opportunity. Cheers shorty.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•