ISO30 Spindle limitations - Cutter Size

[Brian Holcombe]

What are the practical limitations for cutter diameter for an ISO30 Spindle? I'm looking at an HSD 915 spindle which has an ISO30 Taper, and see that I can buy a 30mm spindle for this taper.

Whitehall sells 275mm disks for a 30mm spindle, and so I would like to setup a spindle to carry two of these which I believe would be able to handle tenons that are up to 5" deep.

Planning out a machine build to handle some of the things I do better than my current router table, so I'm planning to build a rigid fixture for holding a spindle, make it height adjustable via CNC controls and build out a hefty cast iron table and cast iron sliding table for tenoning. Keeping it small footprint.

[Joe Calhoon]

30 mm shaft should handle 275mm disk OK Brian. Martin says 300 max for a 30mm.
Not sure if you will get 5” depth. Spacers for 30mm shafts are usually 50 mm outside diameter. About 4 3/8 depth of cut.

[brent stanley]

What are the practical limitations for cutter diameter for an ISO30 Spindle? I'm looking at an HSD 915 spindle which has an ISO30 Taper, and see that I can buy a 30mm spindle for this taper.

Whitehall sells 275mm disks for a 30mm spindle, and so I would like to setup a spindle to carry two of these which I believe would be able to handle tenons that are up to 5" deep.

Planning out a machine build to handle some of the things I do better than my current router table, so I'm planning to build a rigid fixture for holding a spindle, make it height adjustable via CNC controls and build out a hefty cast iron table and cast iron sliding table for tenoning. Keeping it small footprint.

Sounds like a cool project! Keep us posted....

The limiter-style discs at 275mm will give you a 325mm diameter with knives installed, maximum. You'll lose at least 50mm to spacers etc so they say 132mm for tenon length on those ones.

I'd love to see what you come up with!

B

[Brian Holcombe]

Thanks, gents!

[Brian Lamb]

I don't think the shaft size is the issue, it's the 30 taper holder, with it's little tiny retention knob. There is no way I would mount 2 over 10" steel tenon cutters on that and turn them at any rpm. What's the low limit on the HSD915 spindle for RPM, 6000rpm? What's the max rpm on the tenon cutters, 4000 rpm? Sounds like an accident waiting to happen. In the metal working world, you don't run much over 1/2" to 3/4" diameter cutters with a 30 taper machine, and a shell mill is maybe a 2" limit and you can't take much of a cut with it.

Don't mean to be a buzz kill, but you are not in safe territory with this idea and 30 taper holders.

[Wes Grass]

My thoughts are exactly the same as Brian's. I don't think I'd be comfortable running that in a CAT-40 spindle, in my 9,000 lb Fadal.

A 30mm shaper spindle from Felder would be a tenth the price, or less. I have a spare I'd be willing to part with for a reasonable price. Add a 3-phase motor with a matching step pulley (spare part from Felder as well?) and a VFD, and you'd have a real workhorse.

[Brian Lamb]

My thoughts exactly, add a Centroid Acorn and mount the spindle assembly on linear bearings and you could have a pretty simple CNC shaper, although in this situation for tenons only, a simple DRO on the rise and fall would be all that is necessary.

[Brian Holcombe]

Thanks Brian, appreciate the info.

A point, so that you don't think I'm completely off the deep end a danger to myself that should be locked away from my own tools Both Hofmann and Martin have interchangeable spindle setups with a taper and retention knob. I recognize that they certainly spec'd those out to a point where they are heavy enough.....hence my question. Frankly, I don't have a point of reference for what a 30 taper system can handle, so I appreciate your clarification there.

This project is evolving in my planning, I was originally planning a CNC router lift type setup, but I can build that pretty heavy so I started to think perhaps It would be nice to move to a small scale tenoning setup with router capacity. I may shrink this back down to a router level, finish it and then just add an actual shaper when I can do so.

[Brian Lamb]

The small diameter on an ISO 30 taper draw stud is 8mm, so that is the weak point. Any of the shapers with interchangeable tooling are working with HSK63, HSK85 or I think some of the older SCMI units used a larger steep taper unit similar to a 40 taper, or even a large Morse taper. All of which use a much larger than 8mm piece of steel to hold the cutters in.

I understand what you are after, just think you need to stay away from 30 taper, especially with 16k to 24k motors. 275mm disks would probably have a max rpm limit somewhere in the 4000rpm range I'm guessing, so you will want to design around that accordingly.

[Brian Holcombe]

Understood, I'll avoid ISO30 for tooling of this size. A little more research provides that HSK 63 (as you note) is the current standard for these levels of tooling and MT5 was at one point used by Martin. MT5 is pretty hefty and long.

Just a point of clarification, I had no intention of running this tooling up to 24,000rpms and since I cannot find clarification on minimum rpm from HSD I assumed that running down that low would have been possible. It may not and it may not be recommended due to the HP/Torque curve in any case but whatever the setup I end up building I won't be exceeding any of the manufacture recommended speeds in any of my planning.

So, seems I'll need to figure out wether I want to build a shaper or a router and still can't manage to get both.

[Brian Lamb]

The HSD spindles are designed to run at 16k to 24k, so running at 6k you will have almost nothing for hp and take the chance of an overheat situation from the motor running so much slower that it is designed to run.

The long morse taper units were also used in the SCMI units, found a video on youtube of a T130, it has a top nut that presses the long taper into the spindle... doesn't look like the best system to me rotating a long taper into a spindle, asking for galling.

You know, Felder shapers have router spindles and shaper spindles that are interchangeable. Seems to me the best solution for your problem.

[Jared Sankovich]

Understood, I'll avoid ISO30 for tooling of this size. A little more research provides that HSK 63 (as you note) is the current standard for these levels of tooling and MT5 was at one point used by Martin. MT5 is pretty hefty and long.

Just a point of clarification, I had no intention of running this tooling up to 24,000rpms and since I cannot find clarification on minimum rpm from HSD I assumed that running down that low would have been possible. It may not and it may not be recommended due to the HP/Torque curve in any case but whatever the setup I end up building I won't be exceeding any of the manufacture recommended speeds in any of my planning.

So, seems I'll need to figure out wether I want to build a shaper or a router and still can't manage to get both.

The MT5 interchangeable spindle with retaining nut is/was used by the Italian, german, brazilian and polish manufacturers. Im sure there were more, but those are the ones I've seen.

[Brian Holcombe]

Thanks gents, much to think about.

[Jared Sankovich]

If the goal is a small cnc tenoner, you might be farther ahead to find a Harris/Millbury bench top tenoner and rework it for cnc control.

[Brad Shipton]

I pasted the curved for my HSD ES919 below. At 3,000rpm I don't think you will be able to cut a 5" tenon in anything more than 1/4" deep cuts. Cutter mass will be another challenge.

ES919-spindle-curve.JPG