# diamond tipped saw blades; when to replace? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [September 24, 2018, 12:45am UTC](https://boards.straightdope.com/t/diamond-tipped-saw-blades-when-to-replace/821803 "2018-09-24T00:45:17Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![ASGuy](https://avatars.discourse-cdn.com/v4/letter/a/838e76/32.png) [@ASGuy](https://boards.straightdope.com/u/ASGuy)\ **Post date:** [September 24, 2018, 12:45am UTC](https://boards.straightdope.com/t/diamond-tipped-saw-blades-when-to-replace/821803/1 "2018-09-24T00:45:17Z")
I recently completed a partial residing of my home using HardiePlank cement board siding. To make the long story short the folks at the building supply business told me that if I was going to make more than a few cuts with a circular saw (as opposed to nippers) I ought to buy a diamond tipped blade. I did, and the blade performed admirably. But at the very end of my project it seemed the blade was getting tired. The blade was $19, which I considered inexpensive given the “diamond” aspect. But as I said, it performed admirably. My question to those SDMB construction folks, is, when do you decide a diamond tipped circular saw blade needs replacing? ---
**Author:** ![excavating\_for\_a\_mind](https://avatars.discourse-cdn.com/v4/letter/e/e8c25b/32.png) [@excavating\_for\_a\_mind](https://boards.straightdope.com/u/excavating_for_a_mind)\ **Post date:** [September 24, 2018, 12:58am UTC](https://boards.straightdope.com/t/diamond-tipped-saw-blades-when-to-replace/821803/2 "2018-09-24T00:58:08Z")
My experience has always been that when they start to go, they go quickly. It gets hot and stops cutting. ---
**Author:** ![boytyperanma](https://avatars.discourse-cdn.com/v4/letter/b/4491bb/32.png) [@boytyperanma](https://boards.straightdope.com/u/boytyperanma)\ **Post date:** [September 24, 2018, 2:10am UTC](https://boards.straightdope.com/t/diamond-tipped-saw-blades-when-to-replace/821803/3 "2018-09-24T02:10:05Z")
They start cutting slower and eventually you are just burning through stuff instead of cutting. I’ll get a little more life out of them using a brass brush on them to clean them up. The smaller blades are so cheap these days it’s hard to justify not just replacing them as soon as they slow down. ---
**Author:** ![PastTense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pasttense/32/14550_2.png) [@PastTense](https://boards.straightdope.com/u/PastTense)\ **Post date:** [September 24, 2018, 2:18am UTC](https://boards.straightdope.com/t/diamond-tipped-saw-blades-when-to-replace/821803/4 "2018-09-24T02:18:15Z")
You could get a backup blade now and compare the two on the same type material. If the original blade performs substantially worse throw it away; if they perform about the same keep using the original blade. ---
**Author:** ![Projammer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/projammer/32/559_2.png) [@Projammer](https://boards.straightdope.com/u/Projammer)\ **Post date:** [September 24, 2018, 3:16am UTC](https://boards.straightdope.com/t/diamond-tipped-saw-blades-when-to-replace/821803/5 "2018-09-24T03:16:41Z")
> [@ASGuy](#): > > The blade was $19, which I considered inexpensive given the “diamond” aspect. Don’t worry about the low price. There’s a world of difference between industrial diamonds and engagement ring diamonds. We’ll save the artificial price inflation discussion for another thread, ---
**Author:** ![ASGuy](https://avatars.discourse-cdn.com/v4/letter/a/838e76/32.png) [@ASGuy](https://boards.straightdope.com/u/ASGuy)\ **Post date:** [September 24, 2018, 12:16pm UTC](https://boards.straightdope.com/t/diamond-tipped-saw-blades-when-to-replace/821803/6 "2018-09-24T12:16:49Z")
Thanks for the scoop folks. I like **PastTense’s** idea. I can do that and get some hard data.