Another draft FAQ section: Circular Saws

[John Rumm]

Comments as usual please ;-)

[Richard]

The most useful accessory for a circular saw is a Sawboard

reference to this easily made saw guide should be included. It is amazing how much this simple gadget can improve the accuracy and functionality of a workaday circular saw.

Keep up the good work!

Richard.

[david lang]

Excellent as usual John. Could you add something about using a straight edge of a cutting jig like this

[david lang]

Aha! That's the one I was trying to find!

Brilliant idea!

Dave

[ben]

Good but not very versatile. room for improvement though. :-)

[John Rumm]

Yup, will add saw guides etc... won't get much chance to edit until tonight though.

[Ian Stirling]

Not strictly a comment - for discussion. On both table saws, and circular saws, I have on occasion used them as basically really big routers. For example, to make a 10mm notch in some wood, adjust the blade depth to 10mm, make two cuts at either side of the notch to be, back off the wood so that the sawblade barely contacts it, then simply move the wood from back to front so that the saw takes off a 1-2mm depth of wood, using the through cuts as stops. Advance the wood 1-2mm, and repeat until in a few seconds you have a neat smooth-bottomed rebate.

Obviously, this should never be attempted where (on a circular saw) the saw does not keep somewhere firm to rest on, or for a table saw where your hands will come anywhere near the cut. And it needs you to be very aware of the sharply limited depth of cut available in this mode, as well as not applying significant force to the sawblade. Anything I've overlooked?

[Andy Hall]

Along these lines, Trend, Bosch and several others make aluminium guide rails for this purpose.

The simple ones are a clamp on straight edge that have integral clamps at each end. You run the saw against them in the same way as suggested here. They can also be used for routers and jig saws among other tools.

There are more sophisticated ones like the Bosch guide rail system and a better Trend one where you can buy bases that attach to the tool and which then run in a groove on the guide. These are even better.

[Andy Hall]

This is a reasonable technique, although time consuming. BTW, a groove as you describe is normally called a trench (or in 'merkin) a dado. A rebate (merkin = rabbet) is at an edge. You can still use the same method, though.

The way to get around this is with a push block. You can then avoid your hands going near the action area.

With a table saw, it's especially important, because the operation has to be done without a guard over the blade/cutter.

[david lang]

IMO a sawboard is a much better bet than any of the guide rail systems. It's because the sawboard is made oversize and cut with the very saw you will be using, therefore the edge of the sawboard is exactly where the blade will cut.

Much easier to use, not need to mark and allow for the offset.

Plus they are cheap! I have them made up in 1', 2' & 4' sizes for various jobs, all made from scrap.

Dave

[Ian Stirling]

I'm not describing it very well then. It's not a slow technique, for example I was cutting 40*10mm notches out of some 40*20mm timber.

They only had to be approximate, so it was 5 seconds to do the two full depth cuts, and maybe 3 seconds per pass, with maybe 5 passes, leading to a nice smooth result in about 20s, rather than making good the bottom with a chisel/...

[Steven Campbell]

Andy have you any links for these. I couldn't find any on my usual tool sites.

Steven.

[Matt]

The *huge* advantage of a sawboard is you mark only once and so always position to one line with no offsets.

I'd never attempt running a cutting tool against guide rails as you'd run the risk of serious damage to the guide unless it were a bearing guided router cutter.

For circular saws, the clamp on rails - certainly the Trend and generic ones and I think the Bosch ones, might be a marginally more stable guide than a chunk of wood but where you guide off the saw base edge, and consequently have to allow for the offset of the cut from the rail, they are a total pain in the arse to use.

[Pete C]

Also a batten or two can be added underneath so that lengths of timer and decking can be cut square quite easily.

cheers, Pete.

[Andy Hall]

I wasn't suggesting that one should. In the case of a saw you would run the base plate of it against the guide.

In the case of a bearing guided cutter, the bearing is normally run against the edge of the piece of work or a template. YOu wouldn't normally use it with a guide rail.

I don't find so. I don't need to use one that often because I have a table saw with both a rip fence and a sliding table, but where I do use the guide rail with a circular saw, it's a simple matter of adding the fixed offset between blade and side of saw to the measurement. Not really any trouble at all.

[Andy Hall]

However, you do need something different for each tool. It's a trade-off between convenience, accuracy, number of jigs and storing them.

I do make specific jigs when needed, but tend to keep it to special applications where a more standard solution won't work,

[Andy Hall]

Try

and enter "guide rail" in the search. You'll get some extraneous stuff but also links to a number of guide rail types from different manufacturers and at different price points.

[jacob]

FAQ re circular saws surely should mention table saws - esp as hand-held saws are so often pressed into doing things which would be much better done with a table saw. e.g. Ian's 10mm slots - much better done on a table with a wobble saw

(though pricey here). Cheaper from a saw doc =A350 or so and replace half your router cutters at a stroke.

cheers Jacob

[John Rumm]

OK, section added on jigs and accessories with link to the sawguide description.

Clarification added to highlight that this FAQ is about hand held saws (others will be covered separately).

Anything else you folks want to see?

[Kevin Brady]

A few tips on cutting large sheets of ply or MDF with circular saw.

have just bought one and did my first bit of cutting 15mm MDF, but was unsure the best/safest way to support the right hand section if this is large and quite heavy in itself ('waste' bit approx 1 metre long) I ended up with the 'work' piece on my workmate, and the rest propped on a crate with offcuts to suit height - I think it might have been less than safe to be honest.

Any tips right here would be gratefully received.

Cheers

kevin oxford