Sunday 22 September 2013

Penguins, dull mending and exciting knitting...

Since my last post pondering on the failures of my peg bag, not much has been going on sewing (or woolly)-wise.  I've been mainly prodding the baby to prevent him from inserting his small fingers into 240V power outlets, and other important things.

At least I've managed to finish this little chap:


He's a birthday gift for another little boy in the village.  I hope he won't mind the operating system reference!  The pattern is free, just clicky on the badge:

Homepage of free-penguin.org

The pattern does not include seam allowances or many instructions.  I made penguin up in felt, and added 1/4" seam allowances when I cut the pieces out.  The eyes are also top-stitched felt.

This is the second time I've made Tux, the first was for a friend's thesis-hat when he completed his PhD.  There are many potential ways to assemble Tux, but some are easier than others; my method makes the feet construction easier and more reliable.  If I end up making another for my husband's work desk, I'll try to take step-by-step pictures of the construction.  Meanwhile, I'll do a brief text version here, to remind myself (if nothing else):
  1. Cut out all pieces with 1/4" seam allowance.  Cut out eye shapes in black and white fabric, using the pattern illustration as a template.
  2. Top-stitch the white eye-highlight to the black pupil by hand using white thread.
  3. Top-stitch the black pupil onto the white of the eye by machine using black thread.
  4. Place the eyes onto the body pieces using the pattern as a guide, and top-stitch in place using white thread.
  5. You should have four foot-pieces.  Two should have oval holes in them.  (Holes are marked on the pattern, but cut 1/4" inside the oval shape - don't forget that seam allowance!)  For each foot, place a solid and a hole-y piece right-sides together.  Stitch half-way around the pieces in yellow thread, just stitching the toe-edge of them, and leaving the heel flapping open (we'll come back to that).  Turn the feet right-side out.
  6. Your black body-pieces should have matching oval holes in them.  Place the foot-hole up to the body-hole, right-sides together with the foot sticking out in front.  Stitch around the hole, being careful not to catch the free part of the heel you've not yet sewn.
  7. Push the foot through the hole so that it's wrong-way out again.  Now you can match the heels of the two foot-pieces and continue sewing around them in yellow thread.  Finally, push the foot back through the hole, and right-way out again.  The feet are done: cute!
  8. Sew the wing pieces with black thread, right sides together, leaving the top edge free.  Turn them the right way out.
  9. Slash the body part along the lines indicated on the pattern, and insert the wing.  Fold the body along the slash line, right sides together, and sew along the slash line to close it up, catching the top of the wing in it.  Stitch in black thread, as close as you can to the slashed edge.
  10. Stitch the darts at the head and base of the body pieces with black thread.
  11. Stitch the two stomach pieces, right-sides together, with white thread.
  12. Stitch one of the beak pieces to the top of the white bib, right-sides together.  To do this, ease the straight edge of the beak to match the curved edge at the top of the bib.
  13. Place the remaining beak piece right-sides together with the attached beak piece.  Sew around the curved edge with yellow thread and turn the right-way out.
  14. Place the two black body pieces right-sides together, and stitch along the short seam at the bottom front.  Also sew a partial seam from the top of the head down the forehead, past the eyes, to the top of the beak.
  15. Carefully pin the bib-and-beak piece into place within the body pieces, right-sides together.  Lots and lots of careful easing is required, and it's a right fiddle.  Sew around the bib-and-beak, bandage your pin-pricked fingers and make a cup of tea.
  16. Finish the back-seam of the penguin, from his head to his tail with black thread.
  17. Pin the base of the penguin to the rest of the assembly, right-sides together.  Sew most of the way around, leaving a 2-3" gap.
  18. Turn penguin right-side out through the gap.
  19. Stuff penguin firmly, beginning with his feet.  Use a fat crochet-hook to push stuffing into his toes.
  20. Whip-stitch the opening at the base closed with black thread.  Operation complete!
My subject line promises dull mending and exciting knitting.  It's true: I mended the pushchair cover yet again, this time strengthening a torn plastic grommet with two circular patches.  Thrilling.

Much more exciting is the yarn and beads that I've acquired courtesy of my yarn-expert friend for the Boo Knits hallowe'en mystery knit-along, who is kindly sharing her lace-knitting expertise with this n00b.  I'm going to keep my own progress on this knitting secret for now (so sorry for the teaser).  However, if you want yarn eye-candy, you should check out her blog as she's doing the MKAL too, and dying her own yarn for it!  Alas I'm not using Fleece Cottage yarn, but maybe for the next time.  Anyhow, the MKAL starts on October 1st, and you should join too, dearest mystery readers!

Wednesday 11 September 2013

What's (geometrically) wrong with my peg bag.

I should be cleaning the kitchen, but instead I bring you: what is wrong with my peg bag (geometry edition).


From this ugly photo of the ugly bag, I think part of the wrongness arises because the sides of the bag taper inwards towards the bottom.  I'm not talking about the round-bottom shaping, but the slightly sloping sides.  They're not sloping enough to be style, just enough to be looking like a mistake.  And that's because they are.

I put two darts in the bottom of the bag to give volume for pegs.  I failed to calculate that this would make the slides slope inwards and make the bottom of the bag narrower than the top (well, duh).  In the interests of making my pattern correct next time, I thought I'd calculate what I was supposed to do when I drew those darts on my pattern.

Towards the bottom of the bag, my pattern should look like the image above with darts of angle theta and side l, and dart points separated by a distance x.  The total width of this pattern piece is z.  I also marked distance d and delta, which come in handy later.
 


When I come to sew up the darts, the bag will appear to have a width w when viewed from above.  This is narrower than z marked on my pattern piece, because the darts have given the piece some three-dimensional shape.


When viewed in cross-section, lying on a flat surface, the middle of the fabric will rise above the surface by height h (at least, if it were made of stiff card, not floppy cotton).

The interesting quantities to me when I design the bag are theta and h.  The dart angle lets me choose how "boxy" I want the bag to be:  theta = 0 is no shaping at all, theta = 90 degrees is a square bottomed bag, and intermediate values give gentle shaping.  The quantity h allows me to choose how wide back-to-front my bag will be inside.

From my choice of theta and h, I can calculate some useful design parameters which help me to draw my darts in later.  Time to get out my calculator and calculate these numbers:


One can also find a few more useful numbers, in particular x and l which tell me the separation of my dart points, and how long the dart sides should be.

Finally, the total width of my pattern piece at the lower end should be z:
... while at the top by the hanger (where there are no darts), it should just be width w.  So, there we have my mistake, my friends: it's equal to z-w, if you cared.

I can now re-visit my wrong pattern with real numbers.  I'd just drawn darts in at random, but it looks like I used an angle of theta = 28 degrees, with a dart length of l = 4.5cm.  The top of my bag has width w = 34cm.  I find that tan(xi) = 0.601 (that's tan(squiggle), where "squiggle" is clearly the best greek letter), and  d = 3.86cm.  It means the inside of my bag has h = 3.1cm, but really it's 6.2cm across because I used darts in the back and front bag pieces.  Now for the interesting bit: the bottom of my flat pattern (near the darts) should have been z = 37cm across, not the 34cm that I used.  That's an 8% error: enough to make my bag look crap.

Time to re-draw!

I'm also going to change the mouth of the bag, add elastic loops inside to hold the hanger up, and a small fabric loop on the outside at the bottom to pass the hook through when you fold the bag in half for storage.

Sorry for the algebra explosion: if anyone thinks this sort of thing will actually be useful for them then drop me a comment and I could make a calculator-type thing, if maths isn't your forte...

Sunday 8 September 2013

Sunday sewing...


I've been meaning to make myself a peg bag for a while, to save myself having to carefully align the pegs in order to fit them into a stupid ice-cream carton.  No-one has time for that kind of nonsense (that is, peg alignment, not sewing).

My finished peg bag is above.  I'm not all that happy with it, to be honest.  The funky fabric is really the only redeeming feature of this bag.  However, in the interests of honesty, I'm sharing my sewing disasters.

I made the pattern, and although the pegs fill all the way up to the seam-line on the front, I still think the bag is a little too deep.  That seam-line on the front would also look better a tad lower.  The hanger is a wooden children's hanger, but one could just buy wooden adult hangers and saw the ends off.

The bias binding around the openings is too narrow, and not applied at all well (so no close-ups for you - ha!).  In this instance, it was laziness because I found this matching bias binding I'd made years ago, and I didn't want to make more.

In addition, although I used fusible interfacing on the lining for stiffness, I also used volume fleece as an interlining to give it more body.  It turns out that it wasn't such a good idea, and really the resultant bag would have been better interlined with a lightweight batting, with extra quilting on the front or inside.  My bag is much too flumpy and doesn't look neat and tidy as a result - the outside fabric floats uncomfortably over the multiple layers inside.  Oddly, this approach had worked really well on some previous bags I made (see here), but the distribution of weight is very different as they are top-opening, which I think is what saves the day.

The opening looks great on paper, but pulls oddly when the bag is filled.  Perhaps a circular hole would be better next time?

I was going to decorate the front with appliqué and buttons and grosgrain ribbon, but really who wants to throw good notions after bad?

Oh well, at least I get a functional peg-bag, and it's been a learning experience.  The next one will totally be heaps better.

Thursday 5 September 2013

My favourite sewing tool

Did you realise it's national sewing month over in the USA?  I wonder if that translates to the UK: I rather think it ought to!

Anyway, in honour of such, I'm going to nominate my favourite sewing tool:

Other brands of iron are available... :-)

I know it looks ridiculous, but it's true.  I just can't sew without my iron, board and press-cloth.  I have this set up right next to my machine all the time, preferably with minimum moving distance between the two.

Advantage:  Lazy lady doesn't have to move more than 2ft to get to the iron.
Disadvantage:  Numerous close shaves relating to knocking the hot iron off and scorching my feet, or worse: the carpet.

In my opinion, it ought not to be called "sewing", but rather "ironing", as I spend more time pressing my seams than I do sewing them.  I feel it's absolutely key to getting a professional finish.  I know some find it a pain to always iron, and while I sympathise a little (household ironing is indeed tiresome), I find sewing ironing completely different.  It gives you some thinking space before the next step and time to appreciate your work so far.  Plus, subsequent seams always seem to work better if the first lot have been pressed.

In my forays into quilting and tailoring, I read that one ought not to sweep the iron from side-to-side when ironing, but rather "press" downwards, then lift the iron before moving it.  This stops woven fabric distorting, and means your patchwork or garment pattern pieces do not stretch oddly.  Since making that change, I can personally vouch for what a huge difference this makes!  Suddenly my carefully cut pieces all match!

As the photo suggests, I have a cheapo iron with a stainless steel sole plate.  I find it quite adequate for my needs, so long as it can do a good steam shot for tailoring.  You can get those fancy-pants constant steam ones with a separate water tank and generator; while I found one good for thick wool coat fabrics and quilting cottons, it was a disaster when trying to press delicate silks.  So on balance I would opt for the £20 one over the £200 version any day.

A final note on sole-plates.  You can get nasty whiffy sole-plate cleaner that looks like a glue-stick which you can rub on your hot stainless-steel soled iron.  It makes all the fusible interfacing glue that was stuck to it go away and your house will smell horrid for hours.  But at least you have a sparkly new looking iron, and a new-found love for your press-cloth in the future.  I've no idea what you do to clean a ceramic one.

A tangential note:  My iron photo looks like it wouldn't be out of place in Barbie's house- argh!  If only the pink iron hadn't been the best value.  Also, have you noticed that a size "M" cleaning glove fits an average woman's hand, while a size "M" latex glove for the lab fits an average man's hand?  Women: know your limits!  ;-)