Knew Saw

[theresa]

I usually buy 10cm x 10cm so I guess that means a 5".
Thanks Dennis

[susieq]

I have the cheapie saw from the cookies student kit and bought a 5" knew concept saw a while back. I had a lot of trouble with changing the blade and tensioning the knew concept saw and when I finally got the blade it came with re-tensioned, I left it in there even though it much larger than I usually use. Not sure what size the blade is but it's quite thick. I have constant trouble with my cheapie saw especially following lines and sometimes my sawing seems to defy the law of physics - I have to saw at an angle to get a straight line, and I buy the vellorble blades, not the cheapie ones. To cut a long story short, I had some copper I needed to saw a strip off, and as it was 10" and quite thick, decided to use the Knew concept saw. Totally amazed that for the first time I managed to saw an almost perfect straight line.

So, advice would be if you know someone close who has one, give it a try.

New years resolution for me - learn how to change and tension the blade in mine.

Susieq

[Dennis]

Dear Susie,

Sawing in a straight line is to do with tension, not the frame as such. Basically the blade should sound a note when plucked and not just twang.

Other aids to cutting straight are:
1.Sloping the saw forward, instead of keeping it upright as usually suggested and
2.Scribing a pair of lines close together and guiding the saw blade between them.

As for the size of blade, as a general rule a 3/0 will cut sheet from say 0.4mm to 0.8mm. Above that change to a 4/0 for 0.9 t0 1.2 etc.

I favour a traditional saw frame, because I cant be bothered to faff around when a blade breaks, as it seems to do more frequently now. Regards, Dennis.

[Goldsmith]

May I add my sawing advice, sorry Dennis but I was taught that the saw blade should be kept straight when sawing straight lines, sloping the blade forward adds a tension to the blade that will probably break more blade. The saw blade cuts on the downstroke and there is no need for any forward pressure such as sloping the saw. I scribe the cutting line and I cut on the waste side of the scribed line, which leaves the original size of strip or piercing required in tact if the blade wanders.
As for saw blade sizes, I think Dennis has mis typed as he has suggested a smaller size blade for cutting thicker sheet. the 4/0 size blade is good for thinner sheets such as 0.5mm. thick. I use 2/0 size blades for 1mm. to 1.5mm.thick. For sheet 1.5mm. to 2mm. thick, I use size 0. blades.

I have many saw frames each with different size blades fitted for quick use.

James

[ps_bond]

I do slope the blade for long straight cuts if the mood takes me (actually, that's probably better explained as "if I need to cut more than 3" but can't be bothered switching saws"), BUT there's no forward pressure on the blade - the blade is still moving back & forth against the metal, not being pushed into it.

[Petal]

I have the cheapie saw from the cookies student kit and bought a 5" knew concept saw a while back. I had a lot of trouble with changing the blade and tensioning the knew concept saw and when I finally got the blade it came with re-tensioned, I left it in there even though it much larger than I usually use. Not sure what size the blade is but it's quite thick. I have constant trouble with my cheapie saw especially following lines and sometimes my sawing seems to defy the law of physics - I have to saw at an angle to get a straight line, and I buy the vellorble blades, not the cheapie ones. To cut a long story short, I had some copper I needed to saw a strip off, and as it was 10" and quite thick, decided to use the Knew concept saw. Totally amazed that for the first time I managed to saw an almost perfect straight line.

So, advice would be if you know someone close who has one, give it a try.

New years resolution for me - learn how to change and tension the blade in mine.

Susieq

Susieq - I had terrible trouble changing blades and then rang the guys at Suttons (where I bought my KnewC sawframe from). They were really helpful and talked me through it step by step. Since then, I change blades all the time with ease. Sawing is a breeze, but I still use my original saw too, it just depends on what I'm sawing, so don't give up.

[Dennis]

Dear Susie,

Sawing in a straight line is to do with tension, not the frame as such. Basically the blade should sound a note when plucked and not just twang.

Other aids to cutting straight are:
1.Sloping the saw forward, instead of keeping it upright as usually suggested and
2.Scribing a pair of lines close together and guiding the saw blade between them.

As for the size of blade, as a general rule a 3/0 will cut sheet from say 0.4mm to 0.8mm. Above that change to a 4/0 for 0.9 t0 1.2 etc.

I favour a traditional saw frame, because I cant be bothered to faff around when a blade breaks, as it seems to do more frequently now. Regards, Dennis.

Yes, James thank you, For 4/0 read 2/0. As for the sloping saw, I have taken on board what you say, but as a inexperienced and often impatient amateur, I do really find that sloping the saw produces straighter lines for me.

At a course where we had to cut tool steel for the blanking system, the teacher who was an experienced metal worker, advocated sloping and then up-righting the saw alternately. This seemed to deal more easily with this rather tough material. Dennis.

[susieq]

Sawing in a straight line is to do with tension, not the frame as such. Basically the blade should sound a note when plucked and not just twang.

Other aids to cutting straight are:
1.Sloping the saw forward, instead of keeping it upright as usually suggested and
2.Scribing a pair of lines close together and guiding the saw blade between them.

Thanks Dennis - alas I have tried all of that. Sometimes, no matter how tunefully the blade sings when I ping it and despite my very best efforts to keep the blade along the straight and narrow, it is just frustratingly impossible to keep within, or alongside the lines. I really am at a loss (or maybe in denial) to think that it is simply a question of poor tensioning on my part. Still, I'll put in a bit of an extra push when I fit the next saw blade in, see if that helps.

BTW - I think I read somewhere that you should never leave a blade tensioned in the saw frame if you are not using it for a while. I always untension my blade if I'm not going to be using it again for a while. Should I keep it under tension?

Thanks, Susie.

[CJ57]

I must admit I was trained to saw upright, the blade not me, as you are cutting on the downward stroke but impatience often results in a slanting blade and I find they also then break more quickly. In the end it's all down to what works for you but a slow measured upright sawing motion was what Big D drilled into us!!

[caroleallen]

I like to keep my blade upright too. I had a lot of trouble with my Knew Concept when I first had it but after a bit of adjustment, it works fine now, most of the time. I know James advocates sawing from right to left and I wish I could get the hang of it but I do struggle. I'll keep practicing though as I'm sure it makes sense.