V-Scoring a PCB by hand? - Page 1
Forum section: electronics / projects

author: zapta
author_rank: Super Contributor
timestamp: November 18, 2023, 10:24:20 pm
content: I would like to make a few custom SMD to through-hole adapters but using the V-Scoring option adds significantly to the PCB cost (JLCPCB).Is is possible/practical to V-score PCBs by hand? E.g. with a ruler and knife? Any other simple way to cut the PCB along straight lines without inhaling fiberglass dust?

author: spostma
author_rank: Regular Contributor
timestamp: November 18, 2023, 10:40:16 pm
content: there are knives for scoring acrylate sheets that might work well on PCBs.I use a sheet metal shear cutter to separate baords - it seems to survive well.

author: sleemanj
author_rank: Super Contributor
timestamp: November 18, 2023, 10:40:39 pm
content: https://www.eevblog.com/forum/beginners/cutting-protoboards-or-pcbs-to-size/msg1348128/#msg1348128https://www.eevblog.com/forum/eda/clean-way-to-cut-fr4-pcb/msg849477/#msg849477

author: Benta
author_rank: Super Contributor
timestamp: November 18, 2023, 10:49:58 pm
content: Two ideas:Order the boards with1: NPT hole stitching for breakoff.2: milled slots, also for breakoff.

author: ataradov
author_rank: Super Contributor
timestamp: November 18, 2023, 10:58:32 pm
content: Quote from: spostma on November 18, 2023, 10:40:16 pmRegular cheap knives dull in an instant with PCBs. Like one or two cuts of a medium sized PCB and not only they are dull, they don't have any tip to resharpen.The ones with carbide tip will last longer, but they usually have really wide tip, so you need a lot more force and remove a lot of material.If they are just generic breakout boards, why not use separate milled boards option? This is what you want in the end, let them do it.

author: Buriedcode
author_rank: Super Contributor
timestamp: November 19, 2023, 05:11:24 pm
content: For homemade FR4 PCBs (which I hardly ever do these days) I use the back of a cheap disposable craft knife. Two sweeps either side and the PCB snaps perfectly. Works really well for the cheaper FR2 or SRBP "stripboard" which is lot easier on tooling. I don't need it often enough to justify special tools as a pack of 5 craft knives is about £1 and lasts me a year (as I said, I rarely cut boards).

author: zapta
author_rank: Super Contributor
timestamp: November 20, 2023, 04:17:54 pm
content: I ordered this board from JLCPCB and will experiment on it, with knife and with shears. I ordered 0.8mm thickness so should be easier to cut. The arrangement and spacing are temporary and I will compact it once I figure out what works.BTW, ordering five copies of this board cost me $3.5 shipped. We live in good times.

author: Buriedcode
author_rank: Super Contributor
timestamp: November 20, 2023, 06:04:59 pm
content: Forgot to mention - if you have access to a large guillotine for paper - it makes breaking up panels a breeze - but it will require sharpening now and then. FR4 is hell on tools

author: JustMeHere
author_rank: Frequent Contributor
timestamp: November 21, 2023, 06:36:08 am
content: Hacksaw

author: coppercone2
author_rank: Super Contributor
timestamp: November 21, 2023, 08:49:24 am
content: i would just pay, hopefully they have a industrial dust removal system.. no need to deal with that BS for a hobby

author: S57UUU
author_rank: Regular Contributor
timestamp: November 21, 2023, 03:49:36 pm
content: I bought this, works well.https://www.aliexpress.com/item/1005006015286623.html?spm=a2g0o.order_detail.order_detail_item.4.187cf19cJFlltS

author: Bud
author_rank: Super Contributor
timestamp: November 22, 2023, 07:22:52 am
content: Olfa hook knife. Or tile backerboard scoring knife. Both available at Home Depot.

author: zapta
author_rank: Super Contributor
timestamp: December 03, 2023, 04:07:29 am
content: After trying a few suggestion from this thread I settled on cutting the PCB with hand snips. I ordered a 0.8mm PCB and I cut them with an 'aviation snips' like this one. It's straight forward and doesn't generate much dust. The cutting edges are slightly serrated which prevent the PCB sliding out.Left cut, offset, serrated aviation snips. The left cut allows good control to right handed like me, and the offset allows cuts that are longer than the length of the blades. The serration prevents the PCB from slipping forward when you cut. I haven't tried them yet with 1.6mm PCBs.https://www.amazon.com/dp/B000HB35AY

author: EPAIII
author_rank: Super Contributor
timestamp: December 05, 2023, 05:52:52 am
content: Most or all of the utility knife blades that are advertised for scoring are similar to the "hook" style where the working edge of the knife is sharpened in the traditional Vee pointed knife edge. That type of "scoring" blade must push the two sides of a score line aside, opening up a narrow Vee slit in the material being scored.PCBs are made with fiberglass-epoxy, which is a very tough material. Pushing that material to both sides with a knife blade is not easy. So most "scoring" blades do not work well with PCBs.I have a blade that came with a set of initial blades packed with one of the utility knives I purchased many years ago. It has the same Vee pointed knife edge, but that edge points away from the handle of the knife and it cuts with a draw stroke - by pulling the blade toward the user. And AWAY from the sharp Vee. The side edge of the Vee cuts or scores in much the same way as a metal lathe tool with zero degree rake angle. It does not force the material to the sides to create a Vee slot, it RIPS it off the board. This is actually much easier to do and it has the added advantage of staying against a straight edge a lot better than a sharp Vee which can easily drift away from it as you pull it.I have used this blade to score many things over the years. It works well with PCBs, plastic sheets, plexiglass, and almost anything that can be scored and then snapped along the score line.And it is easy to re-sharpen. I have done that a number of times.I have never been able to find another blade like it. But a hook style blade could be converted into a similar one. I will try to add a photo as soon as I can.Quote from: spostma on November 18, 2023, 10:40:16 pm

author: coppercone2
author_rank: Super Contributor
timestamp: December 05, 2023, 09:33:26 am
content: also if you get it right up to your face the nibbler works great so long you align it. kind of slow and you need a good nibbler with a good grip but its a powerful tool. I just take the waste instead of making dust now, not worth making that fiber glass dust IMO. containment nightmarealso you need to flush them with alcohol and grease it once in a while because it gets dirty