# Small T-slot cutters



## Blogwitch (Jun 17, 2016)

I have been looking for these for many years as although I can make a straight woodruffe cutter, I can't make the offset tooth type to carry out a job on a piece of tooling I need to make, putting a small T-slot around the outside edge of a disc.

These are 10mm and 12mm cutters, the thinnest being 2mm, ideal for what I need to do, and the cost was small compared to larger ones. They look to be well ground and I don't doubt they will cut cast iron just fine.







I only ordered these ten days ago, so very quick delivery.

http://www.aliexpress.com/item/Free...aight-shank-T-groove-milling/32336440928.html

http://www.aliexpress.com/item/Free...aight-shank-T-groove-milling/32336520555.html

Plus if anyone is looking for a decent quality chuck for their Dremel, I have four of these for use on my Dremel type tooling.

http://www.aliexpress.com/item/mini....html?spm=2114.10010108.1000015.42.EoPspC&s=p

This information may be of use to someone

John


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## gbritnell (Jun 17, 2016)

Thanks for the link John. These would sure save me hours of work making something like them myself. 
gbritnell


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## Blogwitch (Jun 17, 2016)

Thank you George,
That is why I showed them.

It is fairly easy to make a straight woodruffe cutter, which could cut a straight T-slot if time is taken, but I needed the offset cutters to allow me to cut a curved slot, which if trying to make yourself could take many hours.

It only needs you to save a couple of hours work and they have already paid for themselves.

John


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## Jasonb (Jun 17, 2016)

They look a good buy, I spent that much on a 1/8 x 1/2 woodruff cutter the other day.

So what are you upto with that curved slot - stops on the side of a rotary table maybe?

J


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## Blogwitch (Jun 17, 2016)

You are nearly right Jason.

They are to be used for making a table to manually round over the ends of things like con rods, with stops on the top surface. These were all the rage a few years ago, some have even been shown on here, but all suffered one major hold down problem, which I think I may have solved.

I am also going to be making some very small T-slotted tables for holding down very small items, which always cause me problems when clamping down, the clamps get in the way of small or tiny cutters.

In reality, I have so much material stocks, I have to think up ways of using it all before I snuff it.

John


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## deverett (Jun 17, 2016)

I 'inherited' some T shaped cutters of the 2 types mentioned here a while ago.  Until now, I didn't realise that they were for different jobs so thanks, John for enlightening me.  Some seemed to be odd sizes to me, but but now the penny has dropped and I may be able to find a use for them!

I'd be interested as I'm sure others would as well to see your tooling creations when you can do a write-up, so thanks in anticipation, John.

Dave
The Emerald Isle


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## Blogwitch (Jun 18, 2016)

Dave,

I am waiting for a friend to come around for maybe a week to get my shop into some sort of shape as my health isn't too good at this time, that is why I am just posting bits and bobs in the hope it helps someone.
Once I do get going again, you will get fed up of me posting all sorts.
It is so frustrating having something locked in your brain and not being able to get it into metal.

John


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## tornitore45 (Jun 18, 2016)

> but I needed the offset cutters to allow me to cut a curved slot,



Can you explain?
What/where is the offset?
Why a Woodruff cutter could not cut a round T slot on a plane perpendicular to the spindle?
Are you cutting a T slot on a cylindrical surface? In such case it can still work as long as the teeth are cutting on 3 sides.

Have difficulty visualizing your set up and problem with a regular Woodruff cutter.


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## Blogwitch (Jun 18, 2016)

Mauro,
Have a look at this C-o-C, it shows roughly the shape of the two cutters, and where the T-slot needs to be.






There are two main differences between the two types.

To attempt to use a woodruffe cutter to cut a T-slot, you would first need to grind the shank similar to the T-slot cutter to allow penetration deep enough into the material. They are designed to cut straight slots along the material or cut out a half moon shape to fit in a key.

The second major difference is that the woodruffe has up and down teeth whereas the T-slot cutter has teeth angled as shown.

If you tried to cut a curved slot with a woodruffe, it would bind up almost straight away whereas because of the angled teeth of the T-slot cutter it would allow it to follow a gentle curve as the angled teeth can take material from both the top and bottom of the slot within reason. You end up with a deeper slot for the curved T-nut, but that doesn't really matter, you just make the nut a bit deeper to fit.

I have once before cut a curved slot like this but with a much larger cutter, and it achieved it with no problems, so even though these are much smaller, I expect them to work just as well.

I would suggest you try one of your woodruffe cutters to do a curved (over the top) slot and see how far you get before it breaks.
You can cut a straight T-slot with a woodruffe, as long it is cutting perpendicular to your spindle and you can get the cutter in deep enough.

John

BTW, the bottom pic should be showing it with a curved form rather than flat, I just couldn't be bothered to redraw it.


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## bazmak (Jun 18, 2016)

Hi John,i did a thread on making a small Tslot cutter for the shaper vice
but at that price if I had known I would have bought them
On my thread for the rotary table I described turning a dovetailtail slot
and making tapered stopnuts.I thought the problem with a T slot cutter would be it gashed a much larger slot.The dovetail slot works really well. hope this helps. Regards Barry


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## Cogsy (Jun 18, 2016)

I was having trouble visualising the problem as well but the drawings explain a lot. At this stage I don't think I have a need for such cutters but I'll file the info away for future reference.


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## Blogwitch (Jun 19, 2016)

Baz,

I keep going on about Ali Express, but if you are willing to spend time searching and guessing what a Chinese chappie would call such an item, you can obtain almost anything, from knitting needles to industrial machinery.
You do have to be very careful with delivery costs as sometimes it is more than the item itself, so I usually choose items that have free shipping, and have never had one failure to deliver. 
I have just had a new car, a large Skoda estate, and by searching on there, I have got all the chrome internal and external trims to upgrade it by a couple of models, for peanuts compared to the manufacturers prices. 

You just need to go on there and search.

John

This might help if you don't know the difference between a woodruffe and a T-slot cutter, and how they are usually used.


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## tornitore45 (Jun 19, 2016)

Blogwitch.  Got it, very good explanation. Thanks.


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