i have some 25mm thick x 100mm wide planks coming, its a med soft wood, but i’m going to need them at 20mm. rather than just plane down i’m thinking about cutting some 5mm (or poss thinner) strips (5mm x 100mm) if thats possible.

can anyone tell me the best way to go about this?

i’m not averse to buying a used bandsaw if thats the best option as i’ve been thinking about getting one for a while.

planer/thicknesser?

unless you want to keep the 5mm strips for another job?

Easy with a tracking circular saw, you can shave mm off at a time, although 100mm depth might be tricky……

You need to deep-cut it on a bandsaw ideally.

If you don’t buy one yourself, maybe a local joinery company would do it for you for a couple of beers?

It can be a good idea to make yourself a deeping-fence as the fences you normally get are fairly low so don’t quite offer so much support(although 100mm ain’t too high like..)

Make yourself a pushblock too.

kayak23 is there a minimum size bandsaw i should be looking for to do that? i’ve only ever used a cheap hobby one with a super narrow blade and it twists all over the place.

You know that you need to remove an equal amount from both sides or the wood will warp? so taking off 2.5mm off both sides is a task for a planer/thicknesser.

Not so much a minimum size, but it has to be a sturdy model that can take a wider blade as a narrow blade is more likely to wander. About an inch width upwards maybe.
Saying that, it’s softwood and not massively deep so a decent new blade and a powerful motor should give you a fairly straight cut providing your fence is in line and nice and sturdy.

As mentioned, it’s good practise to try to equalise what material you remove from both sides, but those sort of sizes I’d gamble it not being a huge issue. Try a test piece perhaps. It doesn’t always bow but potentially it can.

Bandsaw will do it with a decent blade but not as a first job + you will need a new blade of the right size type – Tuff Saws in Wales sell excellent blades,
I picked one up tonight
Its an Inca 342 Swiss made – one of the best small bandsaws ever made .

edited model number it cost me £45 90 mile round trip and funny look from wife.