Loppers that crush are usually the bolt
I took the loppers to an old currant stem on a cold Saturday in February. I wanted a clean cut before the sap moved. The blades closed. The stem came away with a mashed collar and a strip of bark hanging. I thought they were blunt. I had wiped them in November. The centre bolt had walked. Held up to the kitchen window, there was a gap. I had been crushing, not cutting.
Loppers are for wood a pair of secateurs cannot span. Two handles, two blades, a bolt in the middle. The bolt keeps the blades in one plane so they meet and shear. If it is loose they gape. The cut starts and then the wood is pinched. Bark peels. You have a wound you will have to tidy, or a stub that dies back. People blame the plant. The plant was fine. The blades were not meeting.
Secateurs that stop cutting are usually blunt. Shears that tear are usually the pivot. Same family of fault, longer handles. I would not buy another pair until I have checked the old ones. Close the handles and look along the meeting faces. Daylight means they will crush. Hold one handle and wiggle the other. Play at the bolt is the fault. Tighten it until the blades meet and still open without a grind. If the nut will not hold a setting, the thread is worn and that pair is finished. A missing washer lets the blades tilt the same way.
Bypass loppers shear like scissors. That is what I want on live wood. Anvil loppers have one blade that closes onto a block. They mash living tissue. They will shorten dead, dry wood. I would not buy a pair sold as if they did both jobs. A tight bolt will not save an anvil cut on a live stem.
Sap and grit pack the joint by the end of a wet February. The handles stiffen. You force them. The blades twist and the bolt walks further. Wipe the joint. A drop of oil on the bolt is enough. That is the same winter habit I wrote about in Winter tools need a wipe and a film of oil. I would do it after the session, not only when I hang them for winter.
The edges still matter once the blades meet. If the bevel is rounded, dress it along the existing face only. I would not grind the flat. A nick from a hidden wire will crush the same spot on every cut. Stop. File it out if you can.
Skip telescopic handles that flex when you squeeze. Extra length is extra miss. Skip a geared pair whose ratchet slips under load. You will chew the stem twice. Skip using loppers on wood thicker than you can comfortably close in one pull. If you have to bounce on the handles, the wood is a saw job. You will roll the edge and walk the bolt. Skip any pair with a rivet you cannot tighten. When that joint loosens you have two sticks.
A spring prune kit is smaller than the catalogues say. Loppers are the extra you add when last year's wood is thicker than a secateur cut, not a reason to buy a wallet of blades. September cut-back is a tool choice is the other week they come off the hook, for woody stuff you would otherwise chew. Late winter and autumn. Those are the two times a crushed cut shows on a small UK plot. A ragged February prune browns. A ragged September stub sits all winter.
I hang them closed. I would not leave them in a trug of wet stems for a minute. A minute is overnight. Overnight is a stuck bolt in March.
If I later add a buy link here, it will be a paid promo.