Most guide clamps tend to flex and wander the greater the length Silverline do a 2.4m and 3m feather edge, I would get the 3m and just clamp it to the board.
If you think you will want to cut boards in the future dead straight - melamine faced chip for carcassing for example, (you can save ££s over bought carcasses) go buy a festool TS55 track saw. Cost you on this job and save you ££s in the future. I wish I'd bought one years ago, wouldn't be without it now. BTW I'm a "dafty DIYer"
Over the summer I helped a neighbour put up some shelves using their tools - a corded B&D hammer drill and circular saw with one of those dreadful multi purpose blades. It was pitiful watching him struggle putting the first set of brackets up and then the splintered cuts on the shelf boards. I went to get my tools and just watched over him whilst he did the work - the difference in quality and ease were remarkable. There is an interesting question over quality tools - because they are so accurate and easy to use do they de-skill people or just enable people with less skills to do better things?
Never noticed any difference between any of the makes of track saw/plunge saw, and I've used the Bosch,festool,makita and Mafell over the years. Everybody says how good the ts55 is but at the end of the day a lack of skill and a blunt blade still give a rough cut.If the grain on the plywood is short grain it's always gonna splinter unless it's been scoredbefore cutting or a plunge saw is available, if cutting more than one sheet the clamp the two sheets together and there's your straight edge just allow for saw bed plus blade that way the motor won't get in the way
Probably better cut with a decent saw/blade, but i doubt much difference with the drill. More likely blunt drill bits causing the issue. I still think an experienced and skilled person could get better results with the cheaper tools than an unskilled person with good tools could do. If not, what is an unskilled worker paying for? Just better tools being brought along? Surely some skill is still needed. Maybe less difference with a semi skilled person, he probably just needs better tools to go to next level?
Not sure they de-skill people, but some tools certainly allow people with fewer skills to do better things. It doesn't take much skill to e.g. use an electric planer. It does take some skill to set-up and use a hand plane. Does the electric planer de-skill? no, the fact you either know how to use a hand plane or you don't is unaffected by using an electric planer. Obviously there is a difference between skilled and unskilled, but that isn't necessarily the same as between professional and not professional (DIY) - not every DIY person is "unskilled", and judging by some of the pictures that crop up here, not every "professional" is skilled . I'm pretty handy and I think the results I turn out, be it tiling, flooring, carpentry, kitchen fitting, simple plumbing, are as good as many professionals. I've been buying tools and making things since I was around 10. I was a kid who got tools for birthday presents! I am also old enough to have had proper woodwork and metalwork lessons at school on lathes, milling machines etc; we learned how to sharpen lathe tools and set-up the screw cutting gear and we were taught how to set-up, sharpen and use hand tools - we learned so much, even things like how to french polish - perhaps I just had good teachers. I would say I am fairly "skilled" but I'm not a pro. The difference is I probably take 3 times as long as a pro would do to do most things, because they just know how to do the job in the most efficient manner. My time is my own. I can take care to do things slowly and neatly, and I certainly have no hesitation in buying good quality tools
It does surprise me today, what we had school and like you had access to both wood and metal lathes, milling machines even a forge. One of our tests was to take a face off a penny but leave the outer rim untouched. In a lot of places these days under 18's, aren't allowed to use a simple power tool let alone the 3 phase monsters we used to have
Y. we had one too. One of the things I made in class was a screwdriver with an aluminium handle. We had to forge and case harden the blade, melt the ally and cast it on to the handle, then turn it on the lathe and knurl it. Kids today have no idea! My metal work teacher was ex -RAF and knew his stuff. Every lesson that involved machines started with dire warnings about leaving chuck keys in machines. If he ever saw a chuck key in a chuck without your hand on it you were banned from using the machine without teacher standing over you all the time. 30 kids, 1 teacher and we were let loose on some great machinery! H&S would do their nut these days.
Mine went missing years ago. I still have the car ramps I made in class though - (and they get used regularly on my MG - although I try to avoid lying on the ground underr cars these days!) We weren't allowed to use the stick welder though - too much risk of arc-eye I guess, so although I designed and cut all the metal, I didn't weld them up.
You can make a jig for your circular saw to cut straight and on the line everytime, its basically a poor mans festool plungesaw. Refer to the video