Slitting saws

Hi,

What speed should I use for my slitting saws [3"dia ] when working on B,M,S ?

And what feed ?

Assuming HSS saw, about 150 rpm should be O.K. Feed rate will depend on the tooth pitch and the power of your machine. Best to suck it and see for your setup. If the teeth clog slow the feed.

Russell

3" diameter, so 9 1/2" circumference, so at 100 surface feet per minute cutting speed, about 125rpm (assuming HSS). I would not go that fast so that the slitting saw will last longer. Coolant of some sort as well would be good. Speed might even be dependent on the width of the blade and how it is supported.

Feed will depend on the number of teeth, mostly.

Edit: too slow for RE! Excuse is that my lady arrived home before the last line was added.

Edited By not done it yet on 19/08/2017 15:44:13

Many thanks to both of you. Had no idea regarding the correct speed. Will play it by ear [and by eye ! ]

Must look after swmbo !!

Don't be surprised if it doesn't cut with all the teeth, none of them do,

chonk-a-chonk-a-chonk

Roy.

With regard to feed rate, think in terms of 0.002" / tooth, so a 100T cutter could be fed faster than a 60T.

Under NO circumstances, key the cutter to the arbor, despite the keyway!

Howard

Sorry Howard but why not key the saw to arbour? I always do, any jamming of saws/cutters due to too heavy cut the belt will slip preventing any damage,worked okay. I don't understand

Mick

Perhaps because not everyone has a belt driven mill? On a gearhead (especially with a plastic sacrificial wheel) maybe better to let the saw slip on the arbour?

Robin

Please allow me to be far less technical - slow, darn slow! Took me ages to get to this conclusion!

There are those that do and those that don't; keys that is. Personally I do. If you get the cutting parameters right you're not likely to jam the cutter. And that means feeding at a decent rate, at least 2 thou per tooth and preferably 4 thou per tooth. When I started horizontal milling I used a very slow feedrate. The whole mill shock, which is good going for a machine that weighs 3500lbs. Upping the feedrate to a proper value cured the problem. For reference my horizontal mill is gear driven, and has a 5hp motor, so you're not going to stall it, or at least I haven't managed it.

As an aside there are two types of slitting saw, fine and coarse tooth. In this picture the saw bottom right is fine tooth, the rest are coarse tooth:

Fine pitch slitting saws are only suitable for shallow cuts, like screw slots, otherwise the swarf jams in the gullets. Coarse tooth slitting saws are happy taking deeper cuts, ½" is not unreasonable.

Andrew

Edited By JasonB on 21/08/2017 09:10:57

That explains it Robin,thanks. I always use my Adcock & Shipley horizontal for slitting which is belt driven, hadn't thought of gear heads

Mick

On top of the above, re keyed or not, the belts should be adjusted/capable of driving the full power of the motor. Slipping belts is not an ideal scenario.

My one horsepower Centec is provided with a twin V belt drive. Thrashing belts or potentially losing power is not the name of the game - one cannot rely on the chosen cutting speeds either - and the motor should be protected (from overload conditions) by thermal cut-outs.

Additionally, the arbor on my machine was never slotted, so deemed unnecessary for extra security (against cutter slippage). 1 1/4" arbors are definitely a considerable step up from the 1" on my machine (an increase of over 50% in cross section). I would not fancy a slitting saw blade disintegrating, particularly at high speed.

Not sure how wide cutters are, to be considered as 'slitting saws' but some of mine are less than a millimetre, so need care during use for both satisfactory life and prevention of jamming.