Angelika enquired about how I made a right angled granny i.e. half a granny square, as she landed on this post. Unfortunately I'd not posted the instructions on how I achieved this and could I remember? No, of course not as I'd made it up as I went along. I emailed back and said I'd experiment again so here is my up to date version of an isosceles granny triangle.
The crucial part is getting the first round correct. I don't think this second attempt is exactly the same as the first but it does the job.
First chain 3 - this is the base.
Put your finger on the last chain and chain a further 2 which stand in for the first treble of the cluster.
Chain 2 trebles into the chain marked with your finger.
Chain 2 and then work another cluster of 3 trebles into the same chain. (This is the first corner.)
Chain 1 and work a cluster of trebles into the next chain which is the second chain of the first 3.
Chain 1 and work 2 clusters of trebles separated by 2 chain into the first chain. (This is the second corner.)
Chain 1 and work 2 clusters of trebles separated by 2 chain into the middle chain of the first 3. (This is the third corner.)
Join with a sl. st. to the first cluster.
There should be 3 clusters or shells across the hypotenuse and 2 clusters down each side. The 3 corners have 2 chain separating the clusters and the sides - 1 chain.
Now it's just like any other granny square except there are only 3 sides. In each corner work 2 clusters separated by 2 chain and on each side work one cluster separated by 1 chain. I suggest that if you want your corners sharper then a 3 chain gap may achieve that. (I've not experimented though.) Here's the second round.
And here's the third.
To make the first 3 chain stronger they could be chained with double yarn.
I've not tried a 3, 4, 5 triangle but I'm sure the same principles will apply. I'll try one later and slot it in below.
Hope this helps, Angelika.
PS Apologies for the pictures not being clear and the rushed annotation - so excited to do the triangle. (That's my excuse!)