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View Full Version : More facemill exercises. Make you own for a buck.



Evan
06-21-2010, 07:56 PM
It's a face mill with only one insert. Hey, isn't that a fly cutter? Why yes, it is and so is a facemill. This took about an hour to make and I was slowed down because I work slow and was taking pictures.

http://ixian.ca/pics7/cutter1.jpg

http://ixian.ca/pics7/cutter2.jpg

http://ixian.ca/pics7/cutter3.jpg

http://ixian.ca/pics7/cutter4.jpg

gnm109
06-21-2010, 08:31 PM
Nice. I'd like to build one. I wonder which insert number you are using?

Evan
06-21-2010, 09:04 PM
The insert is a Tungaloy TCMT11024-PM, Made in Japan

davidh
06-21-2010, 09:04 PM
and i have a ****t load of those kind of bolts i am going to scrap . . . . . .

gnm109
06-21-2010, 10:50 PM
The insert is a Tungaloy TCMT11024-PM, Made in Japan


Thanks. I have a set of TCMT lathe holders and lots of spare inserts. I'm tempted to make a face mill unit like yours. Good photos!

I've had an R8-mounted 1-1/2" facemill for some time. It uses 3 TPG-32 inserts and does a pretty good job. Nonetheless, I like the idea of producing my own tools so I'll have a go at it soon.

:)

Duffy
06-22-2010, 11:26 AM
Evan, that is ELEGANT! I have one silly question. Given the cut loads, does it really need a grade 8 bolt? It seems to me that just about ANY 3/4" bolt-shaped object would be more than adequate for a tool carrier.

Evan
06-22-2010, 11:50 AM
The one reason for the grade 8 bolt is for the threads to hold the insert. Cheese metal just doesn't hold up.

Duffy
06-22-2010, 12:19 PM
Of course! Silly of me to not think of that.

Tony Ennis
06-22-2010, 01:00 PM
Evan, I Googled on that part number and nothing came up except for your post.

Is the rake and relief built into the insert or have you milled the bolt with these attributes in mind?

Black_Moons
06-22-2010, 01:15 PM
Wow evan, did you use HSS to cut that grade 8 bolt??

If so, what feed/speeds/DOC/WOC where you using?

I allways thought grade 8 bolts would be too hard for HSS mills/HSS bandsaws blades/etc and allways only used abrasives on them.

RancherBill
06-22-2010, 01:38 PM
Evan, I Googled on that part number and nothing came up except for your post.

Is the rake and relief built into the insert or have you milled the bolt with these attributes in mind?

It might be Tungaloy TCMT110204-PM
http://www.tungaloyamerica.com/pdf/700%20L.pdf

Great project Evan

Herb W
06-22-2010, 01:51 PM
Evan - nice project. Always good to see ideas for making tooling.



and i have a ****t load of those kind of bolts i am going to scrap . . . . . .

What? scrap perfectly good bolts.... What?

Evan
06-22-2010, 02:08 PM
The inserts are positive-positive so no additional rake or relief is required. That makes the project that much easier. About the only thing that is somewhat critical is accurate placement of the tapped hole. FYI, the inserts require a 4-40 holding screw.

Grade 8 bolts in that size are easy to machine since they don't cool quickly after forming operations. You might run into some that are too hard to work easily but that isn't very common. In order to meet the strength specification they must have a certain amount of ductility since they must be able to be stretched when installed. They cut just fine with HSS tooling as you can see from the pocket I made with a cheap end mill.

jugs
06-22-2010, 05:25 PM
Nice one Evan,

John
:)

Toolguy
06-22-2010, 05:50 PM
I have made a lot of different insert tools out of drill rod. Face mills, Drills, Chamfer tools, End Mills, and Thread Mills. When drilling and tapping for the screws, I find the center of the hole in the insert with the pointed end of an edge/center finder on an insert seated in the pocket, then go .003 toward center and .003 upward so the screw holds the insert firmly in the seat when tightened. I have found that a center finder with the point ground off a little can be a very handy item. Center finders are cheap. I have several.

S_J_H
06-22-2010, 06:13 PM
Neat idea Evan.
Yep, Grade 8 bolts actually machine pretty nice even with HSS bits. I have so many left over from my car days I find uses for them now and then as stock for projects.

Steve

john b
06-22-2010, 09:15 PM
Was that drill chuck holding the end mill supposed to be in the picture. John b.

oldbikerdude37
06-22-2010, 09:34 PM
Was that drill chuck holding the end mill supposed to be in the picture. John b.

It did the job.

Uncle O
06-22-2010, 09:48 PM
Was that drill chuck holding the end mill supposed to be in the picture. John b.

In the lathe ? Not much of a concern...

gnm109
06-22-2010, 09:58 PM
I use my lathe chuck to hold end mills, drills, reamers, hones, smaller boring bars, whatever. I thought that was its purpose.......


.

Evan
06-22-2010, 10:27 PM
Was that drill chuck holding the end mill supposed to be in the picture. John b.

The problem with using a drill chuck to hold a milling cutter is that a 3 jaw drill chuck cannot be depended on to hold against side loads. In the application shown there are no side loads.

hojpoj
06-22-2010, 11:51 PM
Before things go off on the 'endmill in a chuck' tangent...

Evan, could you post one or two more pictures from a different angle? Either the lighting is messing me up or I'm just not firing on all cylinders tonight (probably the latter)- I can't quite see the shape of the pocket milled out for the insert.

Approaching DIY tooling from this angle is pretty nifty. It appeals to the cheap (not clumsy) bastard in me.

Evan
06-23-2010, 03:16 AM
Here you are. It is just milled straight across parallel to the flats that are clamped in the vise. It's a good idea to put a clamp on the end of the bolt resting on the table.

http://ixian.ca/pics7/cutter6.jpg

http://ixian.ca/pics7/cutter5.jpg

hojpoj
06-23-2010, 09:36 PM
Poifect, thanks!

Boot
06-23-2010, 09:39 PM
Wow evan, did you use HSS to cut that grade 8 bolt??

If so, what feed/speeds/DOC/WOC where you using?

I allways thought grade 8 bolts would be too hard for HSS mills/HSS bandsaws blades/etc and allways only used abrasives on them.
You are right Black Moons. I burned up a 2 sided 3/8 HSS end mill today trying to cut it. He must have used a carbide end mill as a matter of fact if you look close you can see it is one. I gave up after that. I'll make mine out of cheesey steel and maybe go to 1" bolt because I have a 1" R8 holder. The good guys at Fastenal gave me that 3/4" bolt , to bad I couldn't use it. Mine was extremely hard.

Evan
06-23-2010, 09:50 PM
Sorry you burned up a tool. Finding a bolt that hard is the exception. As I noted earlier I turned the pocket with a cheap HSS end mill no problem. I normally use carbide endmills for nearly everything including aluminum because the good ones (Garr in this case) are so good at holding an edge and are three times stiffer than steel.

gnm109
06-23-2010, 09:53 PM
The inserts are positive-positive so no additional rake or relief is required. That makes the project that much easier. About the only thing that is somewhat critical is accurate placement of the tapped hole. FYI, the inserts require a 4-40 holding screw.

Grade 8 bolts in that size are easy to machine since they don't cool quickly after forming operations. You might run into some that are too hard to work easily but that isn't very common. In order to meet the strength specification they must have a certain amount of ductility since they must be able to be stretched when installed. They cut just fine with HSS tooling as you can see from the pocket I made with a cheap end mill.


Someone was questioning whether you used HSS or Carbide. As you said above, you used an HSS end mill. I have cut grade 8 bolts with a hacksaw so an HSS end mill should work.

One more question kind sir. In drilling the hole to tap for the 4-40 screw, did you move in a bit from center.....say a thou or two to gain some additional pressure on the insert when seated and tightened?

Thanks in advance. :)

Evan
06-23-2010, 09:57 PM
Yes, move the hole very slightly toward the side wall of the pocket. But, be careful because the rake of the insert will make it possible to chip the carbide edge if it is clamped too tightly against the wall. If it is a bit too close a couple of swipes with a file will correct that. Better too close than too far as it's much harder to unmachine something.

S_J_H
06-23-2010, 10:18 PM
A grade 8 bolt is not all that hard.
But, you do need proper feed and speed for machining this kind of steel. A light cut with to high of a RPM will quickly burn up and destroy a HSS endmill.
Even a little 7x10 mini lathe can easily part off a 1/2" OD grade 8 bolt with a HSS parting blade.

Steve

gnm109
06-24-2010, 12:56 AM
Yes, move the hole very slightly toward the side wall of the pocket. But, be careful because the rake of the insert will make it possible to chip the carbide edge if it is clamped too tightly against the wall. If it is a bit too close a couple of swipes with a file will correct that. Better too close than too far as it's much harder to unmachine something.


Thanks. I'll do that soon.

darryl
06-24-2010, 02:38 AM
I made a similar insert holder from a stub arbor that fits the spindle (MT3), and I thought about the one cutting edge of the insert touching the wall of the pocket. What I did was go the extra step and relieved a bit more of the metal so that the insert touched the side of the wall at a point somewhat below the cutting edge. Not hard to do, and I feel better about it anyway, knowing that the insert is tightly placed on the holder and no cutting edge is taking any pressure, except the one that's supposed to be cutting. Obviously you'd do this before marking and drilling for the mounting bolt.

Oh yeah, I made one mistake with the insert mounting bolt- I left it too long and it stuck out the side of the holder. I drove the flycutter a little too close to one of the hold down clamps one day, and found out the hard way that if you destroy the threads on the exposed part, it isn't going to be easy to remove the bolt. :(

DICKEYBIRD
06-24-2010, 09:37 AM
What I did was go the extra step and relieved a bit more of the metal so that the insert touched the side of the wall at a point somewhat below the cutting edge.(Dope slaps self) Thanks for that! :)

I suppose one could tilt the bolt in an angle vise set to the insert face angle for an even better, full contact fit.

J Tiers
06-24-2010, 09:43 AM
Grade 8 IS "cheese metal"....... they are not really that hard, comparatively. Too hard and they'd be brittle.

But why go so slow? 5000 rpm is 0.0002" depth of cut per tooth. It seems you could, and probably should, feed faster with the insert.

They are not razor sharp, and it may be spending a lot of time "rubbing" instead of actually cutting, even though at 5000rpm you don't see that.

gnm109
06-24-2010, 10:37 AM
Grade 8 IS "cheese metal"....... they are not really that hard, comparatively. Too hard and they'd be brittle.

But why go so slow? 5000 rpm is 0.0002" depth of cut per tooth. It seems you could, and probably should, feed faster with the insert.

They are not razor sharp, and it may be spending a lot of time "rubbing" instead of actually cutting, even though at 5000rpm you don't see that.


I have an excuse. My big Webb tops out at 4,200 rpm....but your theory is good.

Your Old Dog
06-24-2010, 11:04 AM
Before things go off on the 'endmill in a chuck' tangent.....................................

You dont have many post GrassHopper but you must have been doing your homework on this forum!! :D Very astute observation!

Evan
06-24-2010, 11:31 AM
What I did was go the extra step and relieved a bit more of the metal so that the insert touched the side of the wall at a point somewhat below the cutting edge.

Excellent suggestion and easy to implement. I didn't show that part because I was trying to keep the number of steps to an absolute minimum.

That's my story and I will die with it.

Liger Zero
06-24-2010, 05:25 PM
I love the captions "Ignore" "oops" :D

PaulT
06-24-2010, 06:26 PM
Grade 8 IS "cheese metal"....... they are not really that hard, comparatively.

In my experience, most tooling is not made from particularly hard steel, even the high priced stuff. Grab one of your most expensive non-chinese or indian pieces of tooling and draw a file edge on an inconspicuous spot on it and you'll see what I mean.

Paul T.

Mcgyver
06-24-2010, 07:24 PM
the bolt was a handy hulk of iron the right shape and size....but the type of steel is maybe a bit of a red herring? one might maybe the tougher steel in the bolt resists deformation/wear where they insert is in contact but that seems a stretch especially in a home shop with one carrying operator. I would think any hunk of steel would perform as well

Evan
06-24-2010, 08:14 PM
The only problem with low grade steel is the 4-40 threads don't hold up. I use 4-40 grade 11 (or whatever ) countersunk cap screws to hold most inserts like these and they can be tightened enough to strip the threads pretty quick in a grade three bolt and even a grade 5. Other than that there is no other reason to use grade 8 material.

Mcgyver
06-24-2010, 08:14 PM
The only problem with low grade steel is the 4-40 threads don't hold up.

good point

J Tiers
06-24-2010, 10:43 PM
In my experience, most tooling is not made from particularly hard steel, even the high priced stuff. Grab one of your most expensive non-chinese or indian pieces of tooling and draw a file edge on an inconspicuous spot on it and you'll see what I mean.

Paul T.

I have some Dorian insert tooling and it is "reasonably" hard......

I agree very hard is not needed, but that is off-topic.

The point is that grade 8 is not usually so hard that one should be concerned about cutting it. if it IS that hard, there may actually be a problem with it, it may be off-spec for strength.



I have an excuse. My big Webb tops out at 4,200 rpm....but your theory is good.

The speed is fine, it's the FEED I was questioning.

My question to Evan was why so slow a feed that the cut per tooth was in the tenths, with carbide inserts? Inserts are not usually good at "dusting off tenths".

I would expect a couple-three turns just rubbing, and then a cut, then 2 or 3 more just rubbing, then a cut, etc, etc.

Is there some question about the tool that suggests the tiny cut, or is it just "what happened"?

He could have increased the feed, or slowed the speed. Either could easily increase the cut per tooth to 0.001 or so which is more in the usual range (and 5 times what he had).

Evan
06-24-2010, 11:06 PM
My question to Evan was why so slow a feed that the cut per tooth was in the tenths, with carbide inserts? Inserts are not usually good at "dusting off tenths".


I missed that you asked me a question.

The feed was slow to maximize the finish regularity although if you look I also ran a pass at only 500 rpm and 5 ipm which shows no discernable difference.

On the 6061 piece I ran 3 passes back and forth with no change in depth of cut to eliminate, as much as possible, any irregularity from machine vibration. There isn't much vibration with my machine since I am using a 24 volt DC 3 phase brushless motor with closed loop speed control as the main drive motor.

These particular inserts are very sharp and will cut regardless of the light chip load. They are high positive rake but are also very fragile compared to standard neutral rake inserts.

PaulT
06-25-2010, 01:17 PM
I have some Dorian insert tooling and it is "reasonably" hard.......

I would suspect its probably case hardened in the seat area, if you think about it there's no reason to do any more than case hardening on most tooling. But as I stated earlier, its still surprising how much high end tooling is not made from a particularly hard steel or even has case hardening.

Paul T.

Twmaster
06-26-2010, 04:19 AM
Evan,

Have you tried this tool on mild steel?

Evan
06-26-2010, 04:34 AM
Not yet but it will work just fine. This isn't the first such tool I have made. I make most of my tool holders with the exception of collets. There are many ways to skin the cat. A fly cutter type of tool is nothing more than a lathe bit that rotates instead of the work. You can recycle worn out end mills by grinding the end in the approximate shape of a regular lathe tool lying horizontally with some relief. It will do a very nice job of taking light cuts.

Twmaster
06-26-2010, 04:56 AM
I expected as much but -had- to ask! ;)

The fly cutter I use in my little benchtop mill has never done a satisfactory job IMHO. That is a good size for the material I work with mostly. Thanks for the post!

J Tiers
06-26-2010, 10:11 AM
I would suspect its probably case hardened in the seat area, if you think about it there's no reason to do any more than case hardening on most tooling. But as I stated earlier, its still surprising how much high end tooling is not made from a particularly hard steel or even has case hardening.

Paul T.

It may be easier to just make it out of a hardenable tool steel and heat-treat the whole works. Case hardening isn't really so much easier than any other process.... it used to be a lot cheaper, but these days the process time likely costs as much as material is cheaper.

I have a Sandvik cut-off tool that I needed to trim the shank of, because it was a size too big for my toolpost (5/8 instead of 1/2). That thing was harder than the hobs of hell, and it was hard right through.

Frank Ford
06-26-2010, 10:56 AM
Just saw this thread - glad to see I'm not the only nut making bits from bolts. Mine was a quick one-use wood bit, turned on the mill and hand filed but not hardened:

http://www.frets.com/FRETSPages/Blogs/37D28/37PegheadViews/37peghead16s.jpg

http://www.frets.com/FRETSPages/Blogs/37D28/37PegheadViews/37peghead14s.jpg

It's posted as a quick part of a long repair "blog" - -

http://www.frets.com/FRETSPages/Blogs/37D28/37d28_1.html

Tony Ennis
06-26-2010, 12:16 PM
Are you guys not concerned with the bolt threads damaging your collets, or have you removed the threads?

Evan
06-26-2010, 12:24 PM
They don't damage a lathe chuck. A collet clamps near the opening with little force much past that.

gnm109
06-26-2010, 12:37 PM
If you are concerned about the threads, why not get a long bolt and cut them off...?

Frank Ford
06-26-2010, 01:54 PM
Are you guys not concerned with the bolt threads damaging your collets, or have you removed the threads?


Not me. You may notice that my bolt is just a regular one, not hardened.

Twmaster
06-26-2010, 02:42 PM
That would booger an ER type collet if gripped on the threads....

gnm109
06-26-2010, 04:07 PM
That would booger an ER type collet if gripped on the threads....


Right. See my post # 52.

lakeside53
06-26-2010, 05:08 PM
It would do and even better job if it spun:mad: