Not sure that the damper will really do what you wish. Its basic purpose is to keep the bow slightly raised on the return stroke, to reduce blade wear, after the bow has been slightly lifted on the cutting stroke. This lift comes about due to the saw geometry, the blade is not quite parallel to the guides. Hence the work-piece will feel most, if not all of the bow weight at some point on the cutting stroke. The damper will not take very much at all irrespective of the oil or the valve adjustment.

Edited By Clive Brown 1 on 01/11/2017 19:31:43

Nick,

OK, must say that the damper on my elderly Rapidor was never really very good and I eventually discarded it, but I didn't see it as being able to take much weight on the cutting stroke.

If Fizzy gets his to do as you describe then that's a good result..

Clive

For cutting copper tube I think you should be looking at fitting a fine tooth blade but you may not find any finer than about 14tpi which using the 2-3 teeth in contact means a wall thickness of near 6mm, the Rapidor is a good saw but a bandsaw with a fine blade may be better for tube. Using the damper to control the cut is probably a bit optimistic even if it is in A1 working order. I bought my Rapidor to save me time but I just love watching it work, it does save me breaking into a sweat though.

Mike

The thing to do might be to arrange a lever out the back to exactly counterbalance the saw. Then arrange a wire over pulley to weight system to apply a cutting force that does not vary with angle. during the progress of the cut. This works better for bandsaws as the movement of the blade frame adds a complication.
After further thought how about a roller rest out the front that the blade runs on (hopefully hard ballrace bearing resists being cut) and a ratchet driven screw thread height adjustment on every stroke, bit like a shaper adjusting it's cut.

I love that idea, adding weight to a Rapidor

When cutting thin tube on my Rapidor I usually push something into the middle to provide more support for the blade. Usually a lump of wood that happens to be to hand and wedges adequately in place after a rough shave of the corners. Inch thick vertically is usually enough to be stable and provide sufficient extra support.

As fizzy uses a restricted range of tube sizes making up a length of cruciform filler for each size by screwing or nailing suitable bits together would probably be worth the effort. Loose about half an inch for each cut so a foot or two would last a while.

The Rapidor I use has the fixed right angle cut vice holding the work on both sides of the cut. Seems to be more stable with thinner material than the overhung, angle adjustable, version. If fizzy does mostly right angle cuts with an overhung, adjustable, vice it might be worth looking into adding extra support outward of the cut.

Bottom line with a Rapidor is that it follows the Stonehenge design philosophy. Simple, effective, just on the right side of crude, long lived and darn hard to break. Subtle it isn't.

Martin

Cheapskate owners figure weight is cheaper than new blades.  Makes surprisingly little difference to cut times unless huge.

Clive.

Edited By Clive Foster on 02/11/2017 11:01:50

OK, heres a question for all you Rapidor users (I have one too!( which way should the rotation of the flywheel be, and which way round do the blades teeth go, does it cut on the forward stroke, or the back stroke? My rapidor works well, but Every time I ask I get different answers!

Phil

Thanks Clive, that is how mine is set up at the moment. The confusion started when someone (who is "in engineering&quot told me it should have the blade in backwards, ie teeth facing the rear, and then I thought about it, and realised that as mine is three phase, and I cannot find any arrows for direction, it may be wrong! I will leave it as is for the moment, because the workshop is all in a heap because I am re-laying the concrete floor in the main part of the shop (6mx9m) Actually, I will just be the readymix labourer. ^the lads^ will be doing the clever stuff! When it is done and finished, I will take of the belt guard and have a look at the pulleys.

The packing on mine was cut from thin wood, probably about 3/16" thick. 4 pieces in all. Basically a rectangle with a slot for the bolt and a curve to follow the outline of the cast runner plates. I made a replacement from plywood. Anything slightly squishy would probably do.

Edited By Clive Brown 1 on 05/11/2017 10:54:58