Pattern hook substitution

[Nicolapen]

Pattern is for a lilac Sunhat and uses Schachenmayr Catania yarn. Hook listed in pattern is D 3.25mm but they are hard to find in UK

Could I use a 3mm or 3.5mm hook instead

 

Edited January 19, 2021 by Nicjane

[Granny Square]

The whole point of picking a specific hook is to get a gauge that matches the designers' for that pattern.  Try your 3 and 3.5 and see what comes closest to the pattern's gauge, do the math with your swatch, measure your head (where the brim will sit), see how much the swatch stretches and decide which hook will give the best fit.

[Bailey4]

I often have to switch hooks to make gauge so it is best to swatch as Granny Square suggested.  While the designer needed a D you won't know until you work the gauge swatch what size hook you need.

[Nicolapen]

@Granny Square @Bailey4 thanks for the advice but I have not got either of those hooks - was going to have to buy one along with the wool. Having another look at the pattern I have decided it is too complicated so will not be attempting it

Edited January 19, 2021 by Nicjane

[ReniC]

 For future reference, this is a decent Hook Conversion Chart.

[bgs]

Its a good idea to buy a set of hooks if you get the chance.  Its common to have to go up or down a size from the hook recommended in a pattern.  And if you crochet a lot its good to have multiples of the same size for one you misplace one or so if you have multiple projects going you can leave the hook with the project.  My gauge will vary between styles and brands of hooks that are supposed to be the same size and also varies between the same brand depending on if they are my hooks from the 70's versus late 90's.   

[MaryPat]

I've gotten a lot of crochet hooks from eBay.UK for low prices.  It's not unusual to see an estate sale with 20 hooks going for under 20£.  Daughter lives in UK so I could use her home address for shipping and take them back to the US when I visited.  The advantage of buying a lot of them cheaply is that you can eventually see how size is a bit ... what's the word?  I can take 3.5 hook in several different brands and see that they are slightly different to each other in terms of neck length, throat width and thickness of the hook, all factors which cann affect the size of something.  If you're doing an afghan, it may not matter; I find doilies can be pretty forgiving as well.