I would disagree - I much prefer semi flush. Flush cutters tend To dig into the solder joint and sometimes cut some of it away.Semi flush don’t.
in the past I would have recommended Lindström, but they are nowhere near as good as they used to be.
When mine failed after only a couple of years, I bought some from Tsunoda an so far I’ve been very pleased with them.

I think your point is a good one, flush cutters are a preference of mine but I think the argument for semi-flush cutters is a good one, so I edited my original post:

Cutting leads is best done with flush cutters or semi-flush cutters. The difference is the bevel on the cutting edge or lack of it. The former have completely flat ground edges without a bevel on the flat side that cut completely flat, while the latter include a small bevel to slightly pinch the wire as cutting and leave a small stub rather than a flat end.

The advantage of the fish cutter is the ability to trim a wire down to the surface if needed. The advantage of the semi-flush cutter is preventing over-cutting when completely flat to the surface is not intended (most, though not all of the time) and a longer cutting edge life because the apex of the sharpened edge is less acute.

Thanks for pointing that out.

 

I have seen leads literally cut flush to the PCB which I don't normally* do but I can't say I have ever seen a failure because of it. Have you?

Actually, yes, but rarely, and it only happens on single-sided boards, and less likely if the pad is generously sized. I can never understand why people design through-hole boards with tiny pads. I never use anything less than 65 thou.
The though-plating would prevent it on a double sided board, in which case I can see the merits of the full-flush cutter. (Handy if you have calculated your clearance to the chassis without allowing for the height of the solder joint).
Because the semi-flush don’t dig in, I think you could trim a whole board of leads rather more quickly.

 

Actually, yes, but rarely, and it only happens on single-sided boards, and less likely if the pad is generously sized. I can never understand why people design through-hole boards with tiny pads. I never use anything less than 65 thou.
The though-plating would prevent it on a double sided board, in which case I can see the merits of the full-flush cutter. (Handy if you have calculated your clearance to the chassis without allowing for the height of the solder joint).
Because the semi-flush don’t dig in, I think you could trim a whole board of leads rather more quickly.

Yes, single sided board without plated though holes don't offer a lot of mechanical strength in the connection of the soldered lead to the board. I can see that being a problem.

 

Claiming a flush-cut lead will cause a failure on a two-sided board with plated through-holes can cause failures in your applications begs the question, how concerned are you about SMD parts? SMDs must be litersslky falling off the board in your applications of concern.

 

I have concerns about cutting the leads after soldering through hole components to double sided PCBs. Nowadays many of the components I buy have iron (or steel) cored tinned leads. I imagine the end of the lead may rust over time. If nothing else, it wouldn't look very nice to have rust spots on the underside of the board. I alleviate my concerns by resoldering after cropping to cover the end of the flush cut lead with solder. It's time consuming, but I only build 1 offs for home use.

 

I haven't built a through-hole board in quite a while, but I used to do the "crop & bend" technique.
Bend the lead so that it runs parallel to the board, so that it is fixed in place, then cut it at the edge of the pad. Solder the board when it is all assembled.
The solder would then cover the cut end of the wire.

 

I haven't built a through-hole board in quite a while, but I used to do the "crop & bend" technique.

I have tried that, but I find it difficult to leave the leads short enough to not need cropping after soldering whilst keeping them long enough to bend and hold the component firmly in place before soldering. I also find it difficult to not scratch the solder mask with the tips of the cutters when cropping the leads (edit added: if bent before cropping), but that is only a cosmetic thing. With full length leads, on e.g. resistors, I use two pairs of pliars to pull and bend (to about 45 deg) both leads at the same time then 'tack' solder, flush crop, solder neatly. I'm overly fussy about component alignment to make the finished board look tidy.

 

As to flush cutters, it's all a matter of technique as to how "flush" you cut. I usually cut at an angle with the tips nearly on the board and avoid cutting into the soldered joint. And if too much leg is left, I can always trim more.

 

As to flush cutters, it's all a matter of technique as to how "flush" you cut. I usually cut at an angle with the tips nearly on the board and avoid cutting into the soldered joint. And if too much leg is left, I can always trim more.

Just be careful to collect the short shards that may fall somewhere onto the board.

 

For tools i traditionally have purchased Weidmuller , high priced but last a life time,
Wire stripper Stripax model. Adjusts for different types of insulation.

 

Just be careful to collect the short shards that may fall somewhere onto the board.

Or the ones that fall on the floor like the one the Podiatrist removed from my toe.