Hole saw fot notcher

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Hey all built myself a tube notcher but not 100% happy with it as chatters and disintergrates the holesaw after 1 notch. Im currently using a cheap HSS bi metal holesaw but it doesnt do the job. What brand holesaws are people using and for the aussies what is the best brand we have avialble.Heres a pic
Reply:Xu1 Bunnings power tools are not worth 10cents.
Reply:Very crafty I guess the shaft and the positioner are all aligned well?What about drill speed?I forget what brand we use they are at the shop now so I cant tell you what kind they are right now.Very nice what you have so for weld it like you own it
Reply:there is definately to much movement of the hole saw which binds it up. I am going to shorten the shaft and get rid of the arbor and chuck to get the bearing base closer to the tube therefore minimizing chatter. Well thats the theory.
Reply:I would say you have too much travel, you only need a a bit more than the steepest angle you are liable to cut. I would also get rid of the chuck and mount the saw directly to the shaft, with the largest backing plate for the saw to sit on.These hole saws work best at slow speeds, we have guys at work who use a air drill to cut holes with these, the saws last about 4 cuts and take ages to break thought I use either a battery drill or a variable speed electric drill (depending on thickness of steel) the hole is cut in no time and they last for ever.Oh and a bit of lube never go's a miss
Reply:I have the harbor freight tube notcher. I only use the morse cobalt deep cutting hole saws. They last a long time for me and most of my cutting is on schedule 40 pipe.http://www.mkmorse.com/mc2.htmlMiller DVI2Lincoln Precision Tig 225Thermodynamics Cutmaster 38Everything else needed.
Reply:I'd look for the finest toothed hole saws I could find. Doesn't seem to be a choice when buying off the shelf tho.
Reply:Starrett holes saws are good .http://www.starrett.com.au/index.htmhttp://catalog.starrett.com/catalog/...446&Mode=PLISTReadily available in Australia also.Bin anything from XU1 (And Bunnings in general)Id go for a bi metal variable pitch job.Oh, and as Jamlit said if the budget goes that far or you stumble across them the deep cobalts are great .Remember:No such thing as too much coolant. Compressed air works also.A steady pressure , let the bit do the work.Clamp well to minimize drift and chatter.Use manufacturer's rpm's to start with.It will chatter to some extent, its not like a twist drill but if your breaking hole saws its more likely to be set up or operator error than the hole saw itself.Oh, one more thing. you can get hole saws resharpened . Worth while for good bits.Last edited by Brett; 11-25-2007 at 01:42 PM.A good guess is better than a bad measurement
Reply:How many RPM are you doing?  Try slowing down and using some coolant.
Reply:All good tips guys. At the moment i am worried about shaft movement in the bearings. It allows a slight (minimal) up and down movement which wouldn't be helping things. Think the difference of less than 1mm between heim and shaft. Are the heim joints ok to use as bearings? Or should i reconsider bering support design.Thanks for the input.
Reply:Just had  a look at my ones at work.Starret ...very goodPferd......very goodSuttons ....OK just  to Good ,be careful they come in different quality versionsSome German made Suttons that are Tungsten tip for stainless....ExcellentFor your application probably the PferdsOh and cut the shank back thats probably 90% of your problem.A good guess is better than a bad measurement
Reply:Originally Posted by BrettJust had  a look at my ones at work.Starret ...very goodPferd......very goodSuttons ....OK just  to Good ,be careful they come in different quality versionsSome German made Suttons that are Tungsten tip for stainless....ExcellentFor your application probably the PferdsOh and cut the shank back thats probably 90% of your problem.
Reply:it seems to be a good basic design that you have, but i noticed a couple things that may be causing you issues... #1, how well is that pipe being held in? it may be benificial to weld on a piece of angle stock onto your holding screw... it would have to be able to swivle in order to clamp onto the pipe efficently, but if you could figure out a way to do it, it would allow more clamping surface area and hold the pipe more securly within your "Vice", thus cutting down on another possible cause of chatter.#2, i would reccomend (as previously stated by others) to bring your bearings closer to the end of the drill. the longer the distance between the (2) bearings, the more stable it will be... similar to a longer wheel-base on a car. i noticed that both bearings seem to be attached to one primary mounting plate. it woudl help if you were to mount each bearing to their own, individual mouting plates/brackets. it may also be a possibility to encase the spinning shaft within another tube (even EMT/Electrical Conduit may work). it's a bit overkill, but if you can get a good, consistant oil film over the entire spinning shaft within the tube, and keep the shaft spinning at a consistant speed, it is possible to have ZERO contact between the shaft and the tube, and the shaft will not move at all when it is spinning. it's hard to explain, and it's WAY overkill for anyone that only notches tube once in a while, but it's a very interesting process none the less... let me know if you want me to go into further detail.anyway, grip the tube with more stabilizing force and move the bearings a bit, and you should be good to go. remember, the chattering is occuring because there is a difference in movement between the tube and the cutter. even if you can't eliminate the difference, the more you can minimize it, or even syncronize the movement(s), the less chatter you will have.hope that helps,Later,Andy