As a miller of little or no experience I look forward to such a reasoned treatment.

Fairly good explanation of conventional vs climb milling here (and various other places on t'internet, don't really think this warrants magazine space as the information is easily available already.

I think it's plainly obvious that the slitting saw is not climb cutting. I'm more surprised that someone hasn't commented on the workholding. There's very little material actually held in the vice jaws and with a substantial slot already in the workpiece I would have thought vibration/movement of the work would be more of an issue here. That said, the author is demonstrating what can be achieved with the equipment to hand. Overall I think this is a very well written and presented article.

Edited By Graeme W on 07/10/2015 14:43:55

Doesn't everyone have reversible spindles? That one is going anticlockwise.

Mark

Can't see what thread was used might be L/H, anyway, cutter will probably have a key?

Mark

Yes suppose the author may have left and right hand threaded arbors. I thought running slittingsaws with a key was more of a taboo than climb milling

J

PS can anyone confirm which way the blade is facing as the digital mag is not clear enough to see the teeth

Tooth form can be seen but you need a magnifier unless you have rodent eyesight.

Never come across the idea of not using a key, all mine have keyways in them and climb milling is something you do if you want a nice finish but then I never was an apprentice in a tool room, I was trained as designer and only learned the theory having picked up practise from tool makers and machinists working for me.

Mark

I am a practical person and I sometimes use a key. However, the key does not have to be in the cutter. Put the key on the arbor nearest the nut but not engaging the cutter. This will stop the nut unlocking whatever way the cutter is rotating but will probably not break the cutter if it has a jam up.

Edited By David Clark 1 on 07/10/2015 17:02:05

Even with climb milling, there is a depth of radial cut above which there is no longer enough net force to pull the work into the cutter. If you achieve this or slightly exceed it, you are in little danger of rubber pants moments and will have to actively feed the work to the cutter. This applies mainly when using an end mill to remove stock off the end of a work piece. I'm guessing it's something like 2/3 of the cutter diameter.

I was taught not too either unless the work needs it but wouldn't scream in horror. Just laugh if I saw some one doing it and it messed the work up. It's no good saying tighten things up as the degree of that needs some intuition relating to the size of a cut. The grab goes once the lead screw play is taken up anyway.

No key ??????? Any well designed miller will have a shear pin some where. Best hope some one has not replaced it with welding rod etc and that it is annealed brass. Belts would slip on some unless they are over tightened.

Actually some where from the days when masses of people descended on motor factories daily to the sound of a hooter and parts were made by hand I have read arguments that horizontal climb milling is more efficient. However they wouldn't have been using noddy Bridgeports. Not even sure these even have a horizontal attachment.

John

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Edited By John W1 on 07/10/2015 17:41:03

The only factor against climb milling is the existence of backlash in the table drive, the use of ballscrews usually solves this at a stroke but other solutions are available, anti backlash nuts can be spring loaded or hydraulically loaded to eliminate any lost motion, I even worked on an NC mill that used hydraulic rams to move the axes. Unfortunately serious backlash solutions are not often fitted on home type equipment, my humble VMC has a crude pinch screw to tighten the nut but any wear in the screw will soon result in tight or loose spots. I often do light climb milling for a finish cut and adopt Davids suggestion of using the locks to provide more resistance to the axis being dragged by the cutter but this relys on having some feel for the cutting forces versus the table drag. Backlash elimination tends to wear the screw but converting to ballscrews could be done even if CNC is not the final goal but costs a bit just to eliminate backlash. If backlash did not exist I think climb milling would be the mode of choice as all the theory is in favour of it.

Mike