Adapting a block pattern into something else pt. 3 : Modifying the t-shirt back pattern piece and sleeves to make the cardigan

For review read part 1 and 2 of this series.

Next up on my t-shirt block pattern transformation to a cardigan is to work on the pattern pieces for the back. I won't go into too much detail because there isn't much difference from the front.

Trace off the back and add the same length and width adjustments as the front. Extend the shoulder the same amount. Drop the armhole the same amount.

Next I add drill holes to indicate the elastic for the back waist. The elastic takes up some of the extra body ease in the back to make the cardigan appear more fitted. I didn't add additional design ease for extra fullness, just the same wearing ease as the front. If you draft your own pattern, you can add as much or as little as you want. I referenced the cardigan that I am knocking off for placement. In the picture below, the drill holes appear rather large, but that is just for clarity in the drawing. I'll take a picture of the finished pattern pieces when they are ready so you can see what it all looks like. In reality, the holes will only be large enough so a marking pen(cil) can make a mark.

I also modified my sleeve for length and width. My previous blog post on how to reduce/eliminate sleeve cap ease* should give you an idea of how to adjust the sleeve cap. Walk the sleeve cap along both the front and back armhole of the bodices pieces. The armscye should be longer than the sleeve cap. Note the difference and enlarge the sleeve cap so that it matches the armscye. You can do this by slashing and spreading. Do not add any sleeve cap ease. This is a myth perpetuated by pattern drafting manuals and others. You don't need it.

Finally, I referenced some cardigans in my closet to figure out how long to make the sleeve (plus hem) and how wide to make the wrist. I have a tendency to make my sleeves a little longer than necessary because long sleeves from off the rack stuff tend to be too short for me. Also, I worry about shrinkage. I will be pre-shrinking my knit fabric, but some knits will shrink with multiple washings. In any event, add the length you need for your sleeve.

Adapting a block pattern into something else pt. 2 : Pattern modifications to turn a t-shirt into a cardigan

Rather than take pictures of my pattern making process of pencil on paper, I did up some line drawings. Just to refresh, I am tranforming a t-shirt block pattern into a knit cardigan.

I began by laying my t-shirt front pattern piece on to the cardigan that I'm knocking off and took notes on the differences. I had to keep a few things in mind as I compared the two. First, the t-shirt is close fitting with little extra wearing ease. The cardigan I'm knocking off was accidentally shrunk, so I need to add more wearing ease than is immediately apparent. A cardigan or jacket needs enough wearing ease that it is easy to put on and wear over other clothes. I can't tell you exactly how much wearing ease your pattern should have because it depends on what you prefer. Expect to add somewhere between 2-4 inches extra for this style.

The first step is to trace off half of the front pattern.

Next, I lengthened the pattern piece based on my notes. My pattern piece includes the seam allowances and hem allowance. I don't remove the hem allowance, I just make a mental note and add the hem allowance to the length I've added.

To get the angled shape of the cardigan, I extend from the center front at the hemline and draw a line from the high point of the shoulder to the hem. Gravity will pull that point down and create the angle along with a bit of drape.

The greyed out area represents an area that is removed. On paper I scribble in any area to remind myself to ignore it. You could also erase it.

Next, I add in extra wearing ease by moving out the side seam, dropping the armhole, and extending the shoulder line. The extra ease added to the side seam should only be 1/4th the total ease added because we are only working on 1/4th of the total body circumference.

I'm still debating on how much wearing ease to add. I need to compare my body measurements to the pattern to make sure it is enough.










And this is a far as I've gotten so far. I need to make similar changes to the back pattern piece. I also haven't assigned pattern piece numbers yet. Blank forms for managing patterns are available in my Pattern Making bundle or in the book with complete instructions.

Adapting a block pattern into something else pt. 1 : Noting changes for the new style

A block pattern is a sewing pattern that has been proven. It is a pattern that has been trued, perfected and finished with seam allowances. The pattern has been sewn up and tested for fit. In other words, a block pattern just works. A block pattern becomes a part of a pattern file which can be used to make other patterns.

In the industry we rarely draft from scratch. Instead we modify existing patterns (or blocks) into something else. Some pattern making gurus talk about using slopers. Slopers are basic patterns drafted from body measurements and do not have seam allowances. Industry level pattern makers use block patterns, with seam allowances on, to make patterns for new styles*. It saves time.

It's easier than you might think to do this and this is just one example. I'm sure other pattern makers have their own procedures. My own procedures adapt to whatever it is I'm working on and whether I'm using CAD or traditional methods.

The problem:

I have this much loved cashmere sweater jacket. I snagged it off a sales rack a couple of years ago and I absolutely love the cut and fit. You know, the perfect layering piece, warm and soft for those cool days. I usually clean it by running it through the dryer using a Dryel kit. This last time was a disaster as I had left a piece of chocolate in a pocket. Chocolate ended up all over the sweater and everything else. So, I decided to run it through the hand wash cycle on my washer. That was a mistake. While the chocolate did come out, the sweater shrank. It shrunk just enough that I'm not sure I can wear it anymore. It made me very sad. And yes, I know better. I should have hand washed it.

The solution:

I always said that once this sweater was in pieces, I would make up a pattern to make a new one. So here it is. I recently finished up my t-shirt pattern, a block pattern ready to go. I began by carefully laying out the sweater and positioning the front t-shirt pattern on top. I then used scraps of paper to note the differences between the sweater and the pattern. You can see my notes in the picture above.

The notes** usually say something like: Move SH pt out 1/2" (left arrow) ; or Extend hem (down arrow) 3 inches. These notes are sometimes accompanied with drawings as needed. If I was working in CAD, I would just mentally note the differences and make the changes as as I went along. Since I'm drafting with pencil and paper, the notes are essential.

The next step is to trace off the t-shirt pattern and start applying the changes. More on that later.

*There are a lot of pattern making myths out there. I'm trying to keep this blog entry very focused but I'm happy to answer pattern making questions and myths in future posts. Please leave your question or comment below.

**These notes eventually find their way to my pattern piece catalog. I assign a pattern piece number, note the style/pattern piece that the new piece came from, and then tell what changes were applied and any other relevant details. Blank forms for managing patterns are available in my Pattern Making bundle or in the book with complete instructions.

A case study in paying for fabric waste

I recently had a customer bring me some fabric for some flannel blankets. She mentioned off hand that some of the fabric had not been cut very straight by the fabric store sales clerk. This is not terribly unusual - I see it all the time with my custom hemstitching customers. I've seen it with fabric that I have purchased. I don't blame the sales clerks entirely. The sales clerks have to handle (wrestle) the fabric on the bolts, try to straighten it out, and then use dull scissors to cut it. The entire set-up wastes time and gives a poor outcome nearly every time. Is it any wonder that the industry prefers fabric on rolls? This is one reason I always buy a bit more yardage.

This particular case was fairly egregious. My customer wanted to have 3 flannel blankets that measured about 36" x 45", so she bought 6 pieces of flannel in one yard lengths. Every piece was cut like the picture below, some were cut as much as 4 inches off.

If I were to take the conservative approach and say the fabrics were cut only 2 inches off, that would still leave the blankets 2 inches shorter than expected once I cut the fabric straight.

Doing a little math, 6 fabrics times 2 inches means that 12 inches of fabric is wasted. In other words, my customer paid for 1/3 of a yard of fabric that ended up in the trash. I was a bit annoyed considering the current retail prices for fabric. Flannel runs about $6.99 a yard at Joann's which calculates out to about $2.31 in the garbage. And this is the conservative estimate.

Perhaps its not a huge loss. But it's still money in the trash.

I'm not sure if there is a way to avoid this problem. Just buy extra if you need to be sure and have a certain length. Do you have any similar examples?

Repairing a leather sewing machine belt

If you own a sewing machine (industrial or otherwise) with a leather sewing machine belt, chances are that you will have to either replace or repair it at some point. Leather belts will stretch or shrink, and/or break. The climate of your workspace and other variables play into the life and condition of the belt. The area around the belt clip tends to get a lot of wear too. Leather belts are a little old school, but they do have a few advantages. They are customizable and relatively easy to fix.

You'll know you have a problem when the belt ends up in pieces or the machine is not operating properly. The leather belt on my Singer Hemstitcher 72w-19 machine stretched out over time and my machine was not going as fast as it should. It was time to shorten the belt.

Any workshop should have a toolbox. For this job, you'll need these tools:

1. Drill
2. 3/32nd drill bit
3. Scrap wood
4. Pliers
5. Hammer
6. Utility knife (not pictured)
7. Belt clips (not pictured)

I purchased a box of 500 belt clips from Southstar Supply. It sounds like overkill, but believe me, you will probably mess up the clip the first time you do it. Southstar also sells leather belting. You'll want extra length because you never know when you'll need it. Leather belting is not cheap, and there are other places on the net that will sell it in cut lengths. So it pays to repair a belt when you can.

One more note. There is a special tool designed to punch a hole in the leather belt for the belt clip. It's expensive. It doesn't work well (from what I'm told) and you don't need it. A drill with the right drill bit works really, really well.

In my case, I first removed the belt from the machine by bending the existing belt clip apart with pliers. You won't be able to reuse it, so don't bother trying to save it (this is why you want a box of 500!).

Next, determine how much to shorten the belt. It won't be as much as you think. If you make the belt too short, the belt won't fit or the belt will exert too much tension on the machine causing the machine to work harder than it should. Using the utility knife, I only shortened the belt 1/4".

About 1/4" from the cut end, drill a hole through the center of the belt. Be sure to drill the hole on top of some scrap wood so you don't damage your work table! You do need your other hand to help steady the belt as you drill, but I was taking a demo picture by myself. All other safe tool handling rules apply.

Place the belt clip through both holes to test, but don't mash the belt clip closed yet (Yes, I've done this!). Take the belt clip off one side and take the belt to the machine and thread it through the holes in the table. Attach the belt clip to the belt ends and place it over the handwheel and motor pulley to test the tension.

How much tension is needed? It depends on your machine. You need just enough to turn the handwheel properly. In the photo below I'm testing the tension (or slack) on the belt. This is about how much I need to have the machine operate properly.

Finally, mash the belt clip closed with the pliers (sometimes you need a hammer) and you're good to go. It's amazing that a 1/4" shorter in length makes a big difference!