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Power hacksaw Update

You may remember my post regarding a Utube video of my restrored Parkinson Power hacksaw. It was suggested that it was running in the wrong direction. It was recommended that I time it cutting in both directions , and the direction that cuts the fastest is the correct one. I timed it in the "backward" direction and it took some 12 mins to cut through a 100mm x25 mm flat bar , on the flat.The blade was cutting on the backward stroke . Up until today I was waiting for my nieghbour ,who is an electrician , to change the direction of rotation of the drive motor .Well today I finaly collared him and put him to work ,the rotation was reversed . I checked the lift before cutting and found I had to flip the blade around so the teeth pointed forward as it was lifting on the back stroke and dropping on the forward stroke. Any way it took just over 4 mins to cut through the same material and down feed setting as before so I guess this is the correct direction . It's just a bit strange to me as all the power hacksaws I have ever used cut on the back stroke to ward the fixed side of the vice.

Reply to
Kevin(Bluey)
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Yep, i asked a load of questions about a Manchester a few years back and received many conflicting answers .,.

and decided timing was the only way to find out ..as look at it all you like ..you cant quite fathom out whats going on ..as.... even if you ran it very slow you wouldn't see the damping pot do its thing and not work at all....normal speed its too fast to obserb..so you're buggered

yes and reversing the blade was one of the things i did .. there are four configurations you have to time

reverse motor with blade as teeth pointing back-wards reverse motor with blade as teeth pointing forwards forward motor with blade as teeth pointing back-wards forward motor with blade as teeth pointing forwards

the fastest is the right set up.

all the best.markj

Reply to
mark

reverse motor with blade as teeth pointing forwards

I could definitely see once I reversed it that the blade needed to be turned end for end as it was dragging the teeth backward over the material and would quickly bugger the blade. Quite easy to see the lift action while it operates as I had it on the slower speed (two speed machine) .

Reply to
Kevin(Bluey)

And all I said was that it 'looked' wrong! I had no real reason, just seeing the motion made it seem odd to me. So sometimes intuition works - just don't rely on every time!

Henry

Reply to
Dragon

That's how I spotted it on my Wicksteed - with it running in bottom gear you could detect the lift visually.

I am at a bit of a loss as to when I should use bottom or top gear though, with the coolant flowing it seems quite happy to cut through anything that'll fit in the vice in top gear. With that in mind, bottom gear would seem to be superfluous - anybody....?

Julian.

Reply to
Julian

Henry , I owe you thanks for that observation , I could have gone through life with a slow cutting saw. When I first got the machine it had no blade fitted so I had no reference ,only experience of other machines that I had used over the years. I was going on the assumption that all power hacksaws cut on the rear ward stroke .

Reply to
Kevin(Bluey)

It's nice to make a positive contribution some times. Henry

Reply to
Dragon

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