Cutting plywood sheets

[Windy*miller]

I've got a standard sheet of 12mm birch ply (well actually it's two half sheets because I had to get it into the car ) which I want to cut up to make some shelving. Is there a technique (or correct tool) for doing this in a way which means that I don't then have to tidy up the edges with a router?

My circular saw (which admittedly is a cheapo one) is quick but does all sorts of damage to the edges. My jigsaw (which is pretty good and has a decent blade) leaves tidy edges but even with guide they aren't perfectly straight.

I guess just about every woodworker faces this problem at some point, so I'd be grateful for the benefit of everybody else's experience!

Thanks!

 

[9fingers]

Cutting a dead straight line with a jigsaw is challenging for most of us so I would stick with the circular saw, a good sawboard and the correct blade for the job with 60 or more sharp teeth.

I've been trying to find a link to sawboards as they have been mentioned here before but so far I have failed.

Try here http://www.subwoofer-builder.com/sawboard/

Bob

 

[Chems]

I have a £20 circ saw, its Homebases Power Base Brand, but its fitted with a high tooth count freud blade. Thats what you need, it will leave a very smooth edge. Mines a 40 tooth on a 180mm blade. You may get a tiny bit of chip out on the top edge, but you can protect against that by running a bit of veneer tape across where your going to cut.

 

[Windy*miller]

So it's worth putting a decent blade on a cheap saw? I was looking at this www.summitsawblades.co.uk/saw_blade_143.htm but I've never heard of the company.

 

[jedmc571]

Just looked at their site, they seem quite good? very cheap, and they can be re sharpened.

Might be worth a punt? would like to hear myself if anyone's used them.

Back to the post, I had a B&Q Saw with a Freud blade in, served me well for over 10 years.

Cheers

Jed

 

[Windy*miller]

I'll let you know how I get on - thanks for the help.

 

[Racers]

Hi,

The saw only turns the blade, its the blade that does the cutting, so buy a good blade.

Pete

 

[Dibs-h]

So it's worth putting a decent blade on a cheap saw? I was looking at this www.summitsawblades.co.uk/saw_blade_143.htm but I've never heard of the company.

I've bought some of their blades in the past - no complaints!

 

[9fingers]

Hi,

The saw only turns the blade, its the blade that does the cutting, so buy a good blade.

Pete

The other thing for a good finish is that the bearings of the saw should have little or no lateral play.

Bob

 

[cutting solutions]

For cutting ply I would recommend a blade with very sharp alternate bevel teeth. and as many teeth as possible. 180 say 48 teeth.
Normal alternate bevel are only 10/15 degrees. you need something with 35 degree or more.

as said its the blade that does the cutting. cheap blades will not give a clean finish for long. there are lots of softer bodied blades on the market which is reflected in the price.

BTW I can only do a blade 250 mm or larger with sharp alternate bevel
All other sizes are available with standard specs its just the special blade.

 

[Racers]

Hi, cutting solutions

So no blades for my Kity or circular saws

Pete

 

[cutting solutions]

Hi, cutting solutions

So no blades for my Kity or circular saws

Pete

Pete
I just clarified in my post.
the 250 mm refers only to the special blade I recommended.
Doug

 

[mailee]

Before you cut score the line with a craft knife or Stanley knife and then cut on the waste side of this. Of course you still have to have a good blade in the saw. :wink:

 

[speed]

make a zero clearence baseplate for your saw out of mdf

 

[lemonjeff]

So it's worth putting a decent blade on a cheap saw? I was looking at this www.summitsawblades.co.uk/saw_blade_143.htm but I've never heard of the company.

These are very good value for money, don't be put off by the price.

 

[jimi43]

I second the use of good blades even in a "cheap" saw.

My sliding mitre saw was absolute rubbish with the blade that came with it so I swapped it out for a 250mm Freud and it is marvellous now.

Completely different saw.

I totally forgot I could put one in my little portable Ryobi circular saw...that thing is magic...I will have to see how it performs with a decent blade...

Incidentally...you can get some great bargains on Freud blades on fleaBay...even secondhand "used a couple of times" ones...they go for only a few quid...people want new.

Jim

 

[Windy*miller]

Updates:

1. The blade from Summit Saw Blades (www.summitsawblades.co.uk/saw_blade_143.htm) is doing very nicely and is excellent vfm in my opinion.

2. After very nearly buying a Festool saw & guide rail I decided to have one last go at sorting something out myself and made this:

which works fine for what I need. My target was to be less than 0.5mm making a 1220mm across a sheet of plywood and I'm comfortably beating that.

Thanks for all the advice and tips. They were all most helpful.

 

[Windy*miller]

Hmm. Image didn't work - not sure why.

 

[Chems]

Your linking to the page the picture is on, not the picture:

http://farm4.static.flickr.com/3300/462 ... bb6caa.jpg

Its a nice design but you are loosing a LOT of cut depth.

Have a look at this:

https://www.ukworkshop.co.uk/forums/guid ... ide%20rail

 

[ondablade]

Nice job. The Festool saw and guide will normally (provided you have a fresh blade in, and don't get a Cumquats sheet of ply) leave pretty much perfect straight edges with no splintering.

Re. your very nice version. It's hard to see how you are set up, but my sense is that the two critical elements in the Festo system are (a) a very good quality relatively wide kerf and hence sharp and stable ATB blade, and (b) the way the edge of the guide rail acts like a zero clearance saw table insert to press down on the ply right up to the edge of the cut and stop the blade raising splinters.

Festo achieves this by fitting a non slip polyurethane (or something like that) strip under the cutting edge of the guide. (which is very effective, it's not at all inclined to slide even if all that's holding it down during cutting is your pressure on the saw handle)

The (plunging which enables this) blade cuts away a mm or two of this strip the first time you use it, with the result that it ends up in contact with the side of the saw blade to give the required zero clearance. (one side only, so it's advisable to always cut with the guide rail resting on the piece you want the really clean edge on) The edge of the alloy guide rail finishes very close to the blade too, this is probably important in providing a rigid stiffener behind the strip which holds it firmly down on the ply being cut.

Maybe you could if not already manage something like this on your version???

Just a thought. Anybody using a conventional 'off to the side' guide with a plunge cutting saw might be able to fit a similar (thin) facing on the underside of the saw plate. It's take some trial and error, and you'd have to replace it every time you made an out of vertical cut though....