RStevenson Report post Posted March 7, 2015 (edited) I found this pricking iron on Amazon, it says 3.38mm but the product details are extremely lacking. Can anyone tell me how many SPI I can get with this? I'm sewing with 0.6mm tiger thread. Thanks. http://www.amazon.com/gp/product/B00LKUWN5O/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 Edited March 7, 2015 by RStevenson Quote Share this post Link to post Share on other sites
Constabulary Report post Posted March 7, 2015 25,4mm = 1" 25.4mm : 3.38mm = 7.5 I´m not good at math but it should be 7.5 SPI - or not? Quote Share this post Link to post Share on other sites
RStevenson Report post Posted March 8, 2015 Ah yes, that does make sense. Excellent and thank you sir. Quote Share this post Link to post Share on other sites
Boriqua Report post Posted March 20, 2015 instead of starting a new thread I will ask in here since it is a math question that seems relevant. I have the Pro line Diamond Chisels from Tandy http://www.tandyleather.com/en-usd/home/department/tools/stitching-lacing-tools/88043-535.aspx It reads 3mm. I think I should get 8 holes per inch but I get 6? So is stitches per inch different than holes per inch? Or do I just need to go back to Junior high school? Quote Share this post Link to post Share on other sites
