My question... When cutting on my mat, the line's are thicker than my rotary blade of course, so after I have everything lined up do I put my ruler on the line or on one of the sides of the line to get the accurate measurement I need.

I find myself doing different each time, that's why my measurements are off I'm sure.

I know this is probably not clear what I'm trying to ask, but if someone understands and knows which way is accurate please tell me.

For example: If I need to cut it 15", which way would be the most accurate to get that? On the 15" line or on the side of the line, and if on the side, which side right or left?

This is something I've struggled with for a long time. If I knew the right way to do it, it would make my sewing life so much easier. Help!

EVERYONE will tell you, "do not use the lines on your mat for measuring" they are good for keeping your fabric straight but use the same ruler to do your measuring.

I know exactly what you are saying. I have struggled with the same problem every time I cut. I am anxiously awaiting the answer. Thanks for asking.

I think any of those ways would be ok as long as you are consistent each time you made a cut. For example, always lining each piece up to the left side of the line-that way all the pieces are from the same spot and should be more accurate.

Are you saying that you line your fabric up with the lines on the mat? I don't use the lines on my mat, I always use the lines on my rulers.

There are a couple of things that can make a difference in your cutting. I've found that using rulers from different manufacturers can cause problems. If you have rulers from different manufacturers, check them out to see if their lines line up with each other. Also, mats are not always equal in distance between lines when compared with rulers. I only use the lines on the mats to make sure that my material is sitting straight on the mat. I always use my ruler for measuring. How you hold your rotary cutter can make a difference. My quilting buddy tilts her blade in towards the ruler. I have my blade up next to the ruler (not tilted). That can make a difference. (Consequently, we don't cut strips for each other because of how we hold our cutter.)

The thickness of your needle and the thickness of your thread can make a difference when you press your seams one way or another. Make sure you are consistent with which machine you use and what thread you use.

You asked about where to put the ruler on the material...on the line or to one side...I honestly think it doesn't make any difference as long as you do it the same way each time you cut. I tend to put it right in the middle of the line but they may just be me.

I turn my mat to the blank side, then square up the edge i plan to cut from. I take a ruler and lay it somewhere near where i think I will be making the cut, Then i take a smaller ruler, lay it perpendicular to the other ruler on the fabric, and measure over from the cut edge to the bigger ruler to get the exact measurement. check the measurements up and down the edge ("measure twice, cut once") and cut along the big ruller. Don't know if that makes sense or not, but it is a lot more accurate than using the line on the mat. Good luck!

I just wanted to add that when you sew on your quilt, you should first do a test-strip to make sure that your settings on your sewing machine, your cutting and your pressing are accurate. To do that, you should cut two or three pieces of strips equal width, sew them together and then press them. See if the test strips come out at the right width. If they don't, then make the adjustments you need to make so that they are accurate.

Example...take three 2" strips and sew them side-by-side. After ironing they should measure out to 5 1/2 inches wide.

Because of all of life's happenings, it can take me forever to finish a quilt. I make periodic test-strips throughout my quilt making process just because the settings can be messed with or changed without me realizing it.

I think one would be aiming for a five inch wide piece, not a 5.5 inch piece.

With 3 2 inch strips sew together you will get 5.5 until! you sew it to the next two pieces. It is 5 inch finished but will measure 5.5. Clearer? You start with 6 inches sew 2 1/4 inc seams so loose a half inch.

Your question was a very good one and this is all very good advice. However, the same problem occurs with the ruler. The lines on rulers are larger than the rotary cutter. Do you use the center of the line, the right side or the left?

The key is still consistency. You need to pick one and stay with it. Because not all rulers are the same, I do a test piece and measure after cutting. For example, if I want a 3 inch strip, I cut a test strip using the center of the line. I measure it to be sure it is 3 inches. If not, I move to the left or right accordingly. I use those colored tapes to mark the spot I need and stay with that mark for my project.

This takes more time, but saves me time in tearing out mistakes due to bad cuts. Good luck.

I usually lose approximately 1/2 inch with each seam (1/4 inch from each piece/side) and twice that makes one inch loss.

After sewing the two inch strips together, these are my approximate measurements.

1.75 + 1.5 + 1.75 = 5

(2 - 1/4) + (2 - 1/4 - 1/4) + (2 - 1/4) = 5

(Put that in the wrong place)

With three 2" strips you get 5"
With two 3" strips you get 5 1/2"

I can agree with those statements

:) :thumbup:

Math/arithmetic does come in handy now and then!

Turn the mat over and just use the lines on the ruler. I find using the lines on the mat make my cuts off.

Ok so I had a duh moment!! You are right! Will I be forgiven?

i took a class recently and the instructor said to always cut on the left of the line on your ruler and mat if you use mat. Her theory is that this accounts for the scant quarter inch. However, I have found that if I consistently line up with left of the line on either my cuts are more accurate. Consistency is the key

Each seam has 2 1/4" edges of fabric, so out of the first seam of the 1st and 2nd patches, you lose 1/4" off each square, making a total of 1/2" off the width with the 1st seam alone.

Sewing the first 2 sewn patches to a third patch takes another 2 1/4" edges, for another total of 1/2" lost off the width.

So after having sewn 3 patches together, you have lost 1" of overall width.

3 2" patches sewn in a row yield a 5" long strip.
.

I saw a quilting show with Alex Anderson where they talked about how to line up your ruler along the cut edge of the fabric to get an accurate measurement.
The line on the ruler should line up just past the cut edge of the fabric, not on top of it. In other words it butts up to the line but shouldn't extend into the line on the ruler.
I always use this method and find I get the most accurate cuts this way. :D

That's why I like the rulers with the thinnest lines printed on them.

I hate when that happens - :oops:

I line my ruler up with the markings on the mat (look at top & bottom) before cutting. I think that puts the rotary cutter in the center of the cutting line. I put the squared up edge under the ruler & measure with the ruler

I really like to use a Gingher ruler and a Gingher or Fiskars mat. The lines are thinner and I think it is easier to get accuracy. If you can't do that, try lining up your fabric at the line, place your ruler where you want to cut. Then before cutting, get a small ruler (I use the one with the slidey thing in it) and check the measurement from the edge of the fabric to the edge of the placed ruler. If that jives with what you are after, then make sure when you cut that you hold the rotary cutter in a straight up and down position relative to the edge of the ruler.

Another trick -- after you have your ruler placed is to see if the quarter inch and eighth inch marks on your ruler match up at the top of the mat and at the bottom of the mat. These lines are usually thinner on the ruler and on the mat and can help in accurate placement.

Again, as others have said, whatever method you use, be consistant.

Oh, another thing -- check your ruler with another ruler. I actually have one that has a little more than 1/16th extra width in the first quarter inch. It drives me crazy!

Well, it depends on the proportions that one would need or want to achieve to make something 5 1/2", although it is a little easier to just keep the finished piece after seam allowances at 5". For example, the quilt I am working on right now, drawn out proportionally on CAD, required a 1-1/2" strip at a certain point, with another 1/2" to add after that border as well. It solely depends on the quilter and the intentions they have.

To be honest, I really wish my piecing was accurate enough that a thicker line on a cutting mat made a difference! I try to be very accurate, but 1/16th of an inch either way is rounding up or down to me.

Maybe my inconsistencies are consistent?

Cut three strips
Sew them together
Press them
Measure them and see what you get
Make adjustments if necessary

I never use the lines on the mat, except to get the fabric basically square to begin with. I cut a straight edge, then use my rulers. If the piece you are cutting is wider than the ruler you are working with - use two rulers. My 12 1/2" square comes in really handy for this. I line up the cut edge to the little spaces in the ruler markings ( at the inch marks). Works for me! Consistency......

See...this is just why I haven't been successful. No matter how much (I thought) I was doing it right/the same way, my squares were never consistant. I am certified math handicapped. Perhaps I really should take lessons instead of "winging it"

I can cut ok, it's my sewing that gets screwy. I made yellow brick road blocks and I used the "shape cutter". It's a large square thing with 1/2" slots for cutting, it worked amazingly well. There is a smaller one with 1/4" slots too. I just stacked a couple layers of fabric, trimed and away I went. Depending on the width of the strip you can cut several before moving the ruler. Give it a try on old scraps.

I use both, the lines on the cutting mat to line up 2 sides of the fabric, then I use my ruler, to cut..it works fine and I have not had any problems with things being straight, and i am new to all of this, so if ti works for me..it should work for anyone just about.

RIGHT! What she said! Mat measurements are not precise, so don't depend on them for piece measurements. Use a good quality ruler.

Don't recommend EVER using the MAT lines/grids to make cuts ... ALWAYS use your ruler to measure AND to cut by.
Rulers give you more accuracy and I've seen mats that are not even correct in dim.
Always use the SAME RULER or set of rulers when cutting too ... changing around can make a difference ! :)

See this thread:

http://www.quiltingboard.com/t-59056-1.htm

There is a TON of help on there.

Thank you all so much for your help.

I'm going to try using my ruler only to measure with, and just have the mat for my table protection.

The mat I'm sure was my problem after reading some of your post. I used it to measure and my ruler to line up and cut.

I debated about asking this question because I knew what I was trying to ask but couldn't explain it very well on here. Thank goodness you all understood.

This is the same question I've wanted to ask. Thanks for all the answers.

I do not use the lines on my mat for measuring. Rulers for that. I use the lines for keeping the fabric straight on the mat.
Also, I learned in a quilting class, that you should use the same brand of rulers for a project and not intermix. I don't know how true that is.

I cringe when I see people do this....straighten your fabric and then (right handed?) line your ruler up on the inches you need with the line of the fuler ON THE FABRIC...not butted up to it but on the fabric. works everytime

Ditto here. I've been told so many times by workshop/class teachers NOT to, that I have been traumatized!

8-)

which line you choose to line up with; inside of line, outside of line really does not matter as much as consistancy! if you choose to line up with the outside edge of the line then everytime you cut you should do it that way. the reason you are having problems is because you are not being consistant. once you decide how you are going to always do it then you need to measure the actual cut piece and determine if doing it that way means you use a scant 1/4" or a regular 1/4" consistancy is the key :)