Using Bloc Loc Rulers for Perfect Half Square Triangles // Try it Tuesday

Bloc Loc

Once or twice a month, I review a new (to me) or favorite sewing product, technique, etc.  Most of the products are ones that I have purchased–if not, I make sure to note that (there are affiliate links below). If I find something cool I think you might like too, I write about it. Past posts can be found here.

Have you heard of or tried the Bloc Loc rulers? I bought a set of 3 HST Square Up Rulers and think they are fantastic!

The basic idea is that there is a special channel lock that “locks” onto your seam, as you can see below. To trim your half square triangle pairs, you simply trim around the four sides of the square, without moving the ruler.  I happen to have a rotating mat (like this one) that my mom sent me for Christmas,  and it works great. I have also used the ruler with a regular, stationary mat, and it works.

Bloc Loc Detail

There are two downsides to the rulers that I can see–the first is that if you have a 4.5” ruler, you have to trim the blocks to 4.5”. You can’t kind of fudge it and trim to 5”, for example. The other downside is that they are pretty pricey–they are sometimes sold in sets where you get a bit of a discount.

However, I like the ruler enough that I plan to design future HST projects just so I can use my rulers. So if you see a lot of 2.5”, 4.5”, or 6” half square triangles popping up in future quilts, you know why.

You can buy them from Bloc Loc, one seller has them on Amazon (Bloc-Loc Ruler Set) , and I would imagine local quilt shops have them as well, although I haven’t seen them in mine.

Vintage Quilt Revival Blocks

I used the ruler for the Mayflower block on the right–I’m working on another Vintage Quilt Revival Sampler for a block of the month club at Capital Quilts. I think there is still a space or two if you are interested in joining us.

Try It Tuesday Stats:

Name:  4.5” Bloc Loc HST Square Up Ruler
There are rulers for squaring up Half Square Triangles (HST), Half Square Rectangles, Flying Geese as well as Drunkards Path, Apple Core, and a variety of acrylic rulers in a variety of sizes.
Size: 4.5” square
Price: $19.80
Manufacturer: Made by in USA by A.I.A. Plastics Inc of CO & Papillon Graphics of CO
Source:  Bloc Loc at Sample Spree (Quilt Market)
How to use it (per the manufacturer)
Bloc_Loc™ is a revolutionary new channel technology to allow you to accurately “square-up” a half square triangle block while eliminating slipping and ruler rock completely.
Swim Bike Quilt
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  1. Posted January 21, 2014 at 4:25 pm | Permalink

    My husband gave me a set of 6 of these rulers for Christmas and I’m looking forward to trying them on a project soon!

    • Katie Blakesley
      Posted January 21, 2014 at 5:17 pm | Permalink

      What a great gift. I think you will love them.

    • Suzanne Savatteri
      Posted July 26, 2014 at 4:32 pm | Permalink

      I have ordered Bloc Loc rulers from Bloc Loc and, recently, from Erica’s and had to wait to get them. Erica’s has had my order since June 27th and to date I have not received my small HRT. Erica’s gets their Bloc Loc directly from Bloc Loc so I don’t understand such a delay. Anyone else have a delay in getting these rulers?

  2. Mandy
    Posted January 21, 2014 at 6:21 pm | Permalink

    You can’t square up a larger block, but you can square up smaller ones! I’ve used my 6″ bloc loc on everything from 6″ down to 1.5″ HSTs. I don’t think the same would be true for the flying geese rulers, though :)

    • Katie Blakesley
      Posted January 23, 2014 at 10:48 pm | Permalink

      Very true. Thanks for pointing that out.

  3. DianeY
    Posted January 21, 2014 at 8:28 pm | Permalink

    I have a couple of the Flying Geese rulers and I love them. No more wonkiness, which I couldn’t seem to avoid. I have used it for smaller blocks. Just made the first trim with it and then used my regular ruler to trim it to size. It worked great.

    • Katie Blakesley
      Posted January 23, 2014 at 10:48 pm | Permalink

      Good to hear that you love them. I think I need to invest in one…

  4. Posted January 22, 2014 at 10:27 pm | Permalink

    Thanks for weighing in on the rulers. I’ve seen the flying geese ones and wonder if they’d help me get over my reluctance to make that block. And, I really like the colors you’ve chosen for your new Vintage Revival sampler. I got my copy in the mail and have been having so much fun gathering up fabrics.

    • Katie Blakesley
      Posted January 23, 2014 at 10:47 pm | Permalink

      I’m intrigued to try them, too! It looks like another commenter has them and likes them. Maybe I’ll have to invest in one…

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