Why I love the new Maritool shanked down cutters

Hi All:
Recently I posted my first impressions of Frank Mari's new shanked down cutters.
Well here's another job I just happen to be running right now that shows one of their best strengths.

So the cutter is a 1/4" bullnose with 0.020" corner rad, running on a manual Bridgeport clone, milling 360 brass 1.2" deep.
The picture shows perfectly how the shank is cleared.
Ran like a bunny and did a great job on the sidewalls.
I'm a happy guy!

Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

As I've been working with accomplished programmers and machinists (being a novice myself) I've found that the necked-down shank is a *very* powerful tool in the shop. We have tools ground like this all the time now!

Been doing this myself on standard cutters, using a michelin T&C grinder for the last 20 years as a moldmaker.
Glad to see Frank and a few others have picked up on it.

Its a pain in the ass to relieve a 1/2" ball mill for 4" reach yourself.

A bit of a question Marcus,
What sort of slacking off do you do at those depths opposed to a stubby cutter?

I generally push a stubby cutter in there first and then go for the "relieved by myself" one to finish off but I find that if I go 50% of my cutting parameters I still get deflection. At times I just baby the longer cutter from the top down so that I know that there will not be any mismatch.

I have seen how you push your cutters and honestly value any advice that you have for me.

Hi NAST555:
I ran this particular job by babying it as you describe, so my DOC was only 0.025" and I was feeding manually on the Bridgeport so at a guess my feedrate may have been 30 IPM or thereabouts but my spindle speed was only 3000 RPM because the Bport starts howling alarmingly above that.

If I was running these in production on a VMC, I'd drop in a bigger cutter and push it to the limit of what my part fixturing can take, but these 1/4" ones are the first of the series Frank is intending to offer (assuming they're popular enough to justify Frank putting them into production).
I actually made the request to him to try to bring something like this to market because like so many others, I got tired of spinning down my own.
The reduced shank on these goes all the way up to the back end of the blank so you can choke them up however much you want but you can also stick them out as far as you dare too.

That to me, is the beauty of this design...no longer do you need to stock a bunch of necked down cutters in various lengths, and the short flutes make it super stiff compared to a long flute cutter.

This particular model is 1/4" diameter but the shank is 6mm, so it goes nicely in a standard ER collet.


To answer your query more directly, if this was all I had, and I had to make time with it, and couldn't accept re-chucking the cutter to get my reach, I'd plunge rough to load the cutter primarily axially, especially since this particular geometry allows for great chip evacuation.
I've found I can push a cutter much harder that way without doing it, or the job any harm.

Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

Thanks for the heads up. I need some of these and didn't know maritool was making them. Hopefully they catch on and they make a decent assortment as time goes on. I would think 1/4, 3/8, and 1/2 would be fairly popular.

Griffin said:

Thanks for the heads up. I need some of these and didn't know maritool was making them. Hopefully they catch on and they make a decent assortment as time goes on. I would think 1/4, 3/8, and 1/2 would be fairly popular.

Click to expand...

We would definitely be in the market for 1/4 with 6mm shank, 3/8 with 8mm shank and the 1/2 with a 12 mm shank. Add a .02 or. 030 corner radius and your talking a needed niche.

Sent from my SM-G960U using Tapatalk

Yup, they're handy. That's why I bought some of these...



[Not one of Franks, obviously]

In my case, I mostly wanted them for large area surfacing, but the reduced shank is still helpful in other ways - I can cut them if I want them shorter, or use them full length for deeper access.

Why are we talking about these as new? Mari tool has been selling these for years. I have some I got from him 5-6 years ago, I dont use them often only as needed. I have some of the three flute ones for aluminum and plastic and the four flute ones for steel and stainless.

Charles

Hi Charles:
The "new" is in the selection that's available and that they are stub flute, bull nose, on long, reduced diameter shanks.
So yes; Frank is just expanding this line he's had for a while, but the upshot is that I made the request here on PM in response to a thread he had running on making a line of taps with fractional sized shanks.
I had been pestering Garr for years about introducing what I actually need instead of forever accepting all sorts of compromises, and they never took me up on it.

Frank was gracious enough to respond positively to that request and this is the result.
I'm planning to switch over completely to these new cutters as I deplete my old stock, and as Frank makes more and more available as stock items.
I HATE stocking a gazillion different cutters in all styles and all sizes; having a crapload of cash tied up in them and then STILL not having the one I want for a particular job, and this is the best compromise for roughing I've found so far

My interest in bringing these to everyone's attention is twofold.
The first is self interest...I want Frank to have enough of a market for these that he is justified in expanding the line so I can buy them from him and stock them as my regular inventory in all sizes from 1/8" up to 1/2" which is 90% of what I use for roughing.

The second is that I want others to be aware of the option so they can take advantage of their strengths too.

So yeah, Charles, you're correct that some limited stock has been available for a while...I just want to see more sizes available in stub flute with bullnose ends.

Milland, I've been looking half of forever for these and could find no sources...I guess I'm not as good at Google as I thought I was.
The smaller sizes were particularly problematic...I was aware of some larger ones but not small ones and not with stub flutes.

Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

I picked up some of these after reading the other thread as well. Love em, worked way better than getting a long flute endmill for deep cuts. I stuck a 1/4" endmill out almost 2" for one job to finish a deep pocket, then choked up on it for the next job for general profiling and pocketing. Same tool. I'm definitely picking up more of these, the flexibility is unmatched.

I have some reduced shank tooling from other manufacturers but it still has a nominal sized shank so I can't make it any shorter than the start of the neck. When I need a stickout that's in between sizes/lengths I am SOL and have to go up to the next longest, sacrificing some rigidity. Not so with these ones, just extend them only as much as needed.

We have stocked reduced shank endmills as a standard product for almost 10 years now. This new series of reduced shank end mills are just a little shorter so they are more affordable.

implmex, thanks for the great feedback and posting the picture. It is a great visual to really show why these cutters can be so useful.

implmex said:

Hi NAST555:

The reduced shank on these goes all the way up to the back end of the blank so you can choke them up however much you want but you can also stick them out as far as you dare too.

That to me, is the beauty of this design...no longer do you need to stock a bunch of necked down cutters in various lengths, and the short flutes make it super stiff compared to a long flute cutter.

This particular model is 1/4" diameter but the shank is 6mm, so it goes nicely in a standard ER collet.



Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

Click to expand...

Thanks so much for the direct reply. Much appreciated. now the feature that it is necked all the way up is seriously a plus point, WELL DONE FRANK! It is as though he actually knows the crap that machinists have to put up with on a daily basis

Now Marcus, on a serious note, why 1/4"? I though you Canadians were with us on the bastard Metric thing

Hi again NAST555:
You wrote:"Now Marcus, on a serious note, why 1/4"? I though you Canadians were with us on the bastard Metric thing"

Short answer...because I'm a GOMER, and a LUDDITE and I don't need no new fangled metric system to make no stinkin' parts!!

Longer answer: Imperial is still quite a bit easier to source in Canada and seems to be cheaper too.
It's getting better but slowly.

There will come a time when I have to replace all my mikes and set all my DRO's to metric but not yet!

Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

Actually most orders going to Canada are always a combination of different Inch size endmills and drills. A few Metric here and there, but mainly Inch sized tooling. I have no problem stocking both.

I would run everything metric if I could but the availability and selection of Inch tools is so much higher.

Frank thanks for chiming in, love your tools, just got my shipment in today thanks again for great products and service.

Charles