How do i cut a straight line

[marsaday]

I am slowly building a cupboard and shelves.

I have cut the front panel of the cupboard and i have also cut out the square opening for the door which i will make out of left over oak floor boards.

I used a jigsaw to cut the lines for the door and so the left and right shorter sides are pretty plumb, but the top and bottom longer lengths are a bit wiggly in places.

It is fine for me to cut off another 3-5mm top and bottom.

So my question is how do i make a new cut which is super straight. What equipment do i need. I have bought a router and wondered if i could use this ?

 

[nev]

...
So my question is how do i make a new cut which is super straight. What equipment do i need. I have bought a router and wondered if i could use this ?

Clamp a straight edge to the workpiece to guide the router.

https://www.youtube.com/watch?v=ywRv7c3_Mc0

 

[marsaday]

Ok thanks, makes sense.

 

[nev]

anything straight - the factory cut edge of a sheet of ply for example.

 

[LancsRick]

As a top tip, never try to use the jigsaw for straight stuff - the blade has enough flex that it can wander. Router and straight edge is always a good choice.

 

[Rich C]

I'm not sure what job a jigsaw is actually the right tool for. They always seem like a second option to something better.

 

[MikeG.]

I'm not sure what job a jigsaw is actually the right tool for. They always seem like a second option to something better.

They're a building site tool.

 

[owen]

I'm not sure what job a jigsaw is actually the right tool for. They always seem like a second option to something better.

Pretty much the only things mine gets used for are sink and hob cut outs in worktops and very occasional scribing. Apart from that they're pretty useless.

 

[Bm101]

I'm not sure what job a jigsaw is actually the right tool for. They always seem like a second option to something better.

They are handy for the fast scribing of internal skirting joints (if you don't have a coping saw) which can be at risk of opening up over time if you just mitre them particularly if one of the surfaces the skirting is fixed to is a moveable surface such as let's say a wooden box built to hide a consumer unit.... :-"
Just saying. Although a coping saw would probably be better if you already have a jig saw it's a better saw for scribing that particular bit of skirting because it's already been paid for.

No idea why I'm posting this link. Just in case. O
https://www.diydata.com/carpentry/skirt ... _board.php

 

[Bm101]

Marsaday. I'm just a beginner, and I'm guessing as to your experience but if you are about to fire a router up for the first time please take the time to do some reading. Alan Holtham 'Complete Routing' and Ron Fox 'Mastering the Router: A Complete Course' Both get good mentions regularly as good books to follow. \Should be able to pick one up for less than the price of a couple of pints. Bit dated superficially but the advice and instruction is solid. My apologies if I'm teaching Granny to suck eggs. Hard to tell on the net. Router is a wonderful bit of kit. It will also remove your finger faster than you can think about how fast 3200 rpm really equates to with a spinning metal cutter. Book should be available for shy of a tenner.
Sorry if I sound like I'm preaching.
Anyway.
Cheers,
Chris

 

[Trevanion]

Router is a wonderful bit of kit. It will also remove your finger faster than you can think about how fast 3200 rpm really equates to with a spinning metal cutter.

Except that routers tend to be run from around 8000RPM up to 30000RPM, most fixed speed routers are about 25000RPM so let's go with that number. At 25000RPM the bit will rotate 416 times every second, most router bits have two cutting blades so that results in 832 cuts every second. Now if your finger does somehow manage to get in the bit it would usually be a split second thing so to be on the generous side let's say it touches the bit for 1/10th of a second, that's 83.2 cuts sustained on your finger in 0.1 seconds. Now, most router cutters these days are limited in how much cut they can take off by the fact that the bit is a solid piece rather than a 2-wing cutter like the older ones were, So we'll say that every revolution one cutter can take off 0.5mm, between the two cutters cutting 83.2 times in 1/10th of a second in theory you could take off 41.6mm of your hand in 1/10th of a second.

This is, of course, all theoretical. You're not actually going to stick your finger in there :wink:

 

[Rich C]

At least it would be straight cut on your finger though. :wink:

 

[Trevanion]

At least it would be straight cut on your finger though. :wink:

No, it would actually be a radial cut since the cutter is spinning. :roll: :wink:

 

[Bm101]

Router is a wonderful bit of kit. It will also remove your finger faster than you can think about how fast 3200 rpm really equates to with a spinning metal cutter.

Except that routers tend to be run from around 8000RPM up to 3000RPM, most fixed speed routers are about 25000RPM so let's go with that number. At 25000RPM the bit will rotate 416 times every second, most router bits have two cutting blades so that results in 832 cuts every second. Now if your finger does somehow manage to get in the bit it would usually be a split second thing so to be on the generous side let's say it touches the bit for 1/10th of a second, that's 83.2 cuts sustained on your finger in 0.1 seconds. Now, most router cutters these days are limited in how much cut they can take off by the fact that the bit is a solid piece rather than a 2-wing cutter like the older ones were, So we'll say that every revolution one cutter can take off 0.5mm, between the two cutters cutting 83.2 times in 1/10th of a second in theory you could take off 41.6mm of your hand in 1/10th of a second.

This is, of course, all theoretical. You're not actually going to stick your finger in there :wink:

Point 1. Sorry My Bad for false info. Maybe I read somewhere 32000 rpm. Whatever the speed it's very speedy. Personally It's table saws that terrify me (I don't own one) and I once had kickback off a circular saw while kneeling over a large bit of wood and overstretching that had me giggling in terrified relief after it didn't sever my femoral artery. Bad practice that I got away with.
[youtube]Rv1HyZMXjog[/youtube]
Point 2 . I Think I went out with that lass once.

 

[Trevanion]

Personally It's table saws that terrify me (I don't own one) and I once had kickback off a circular saw while kneeling over a large bit of wood and overstretching that had me giggling in terrified relief after it didn't sever my femoral artery.

I also used to be terrified of them, then you just get used to them as you're forced to work with them and not much really scares me anymore but they still command a lot of respect. Absolute worst kickback I've ever had was ripping down a celotex sheet of all things, I think I managed to somehow twist the sheet on the blade and it threw the sheet back at me with enough force to knock me back a few steps. I've had offcuts turn into missiles before as well, I once did a large bevel cut around a window casement so that it fitted into a tapered window opening, to do this I just cobbled up a quick false fence on the TS and plunged the blade into it at the right angle and started cutting. Now, I knew that the offcuts would have a tendency to creep back gently because they were trapped between the blade and fence and they did so without too much trouble but on the last cut one climbed the back of the saw blade and since it had nowhere to go it got forced into the fence hard and shot out of the machine like a bullet and whacked against the nice new £20k spindle moulder , fortunately no machines were harmed.

That was an 8mmx8mm triangular offcut of Accoya, shot out of the saw and pierced a hole through a 12mm sheet of OSB. Fortunately the offcut box was in the way of it hitting the spindle moulder once again If a person had been running the spindle moulder I suspect they would've been skewered quite badly./

We try to keep things safe as possible but some accidents are just unavoidable sometimes.