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View Full Version : Flycutter / boring head - not for the faint hearted !



John Stevenson
01-02-2010, 10:10 AM
Thought I'd post this as an example of working outside the box.

Some while ago whilst working sub contract for an engineering company we sent a large steel plate out to be faced and have a large locating pin hole bored in and an 'O' ring groove for a seal machined in.

When It came back and we came to assemble it [ against the clock as usual ] we realised that the 'O' ring groove had been missed out. this plate was far to big to go on any of our machines so I came up with this.

http://www.stevenson-engineers.co.uk/files/Flycutter1.jpg

Big steel disk with a 5/8" shank screwed and pinned into the back face, onto this was bolted a scrap top slide off a Myford ML7 with a tool block / holder screwed to this.

This was fitted to a large magnetic drill, clamped for extra safety and lined up on the plate and the groove machined in.

Worked a treat and provided the revs were kept down it works well.

Looking a bit sorry for itself but it's been hiding in the back of a cupboard for quite a few years.

.

rockrat
01-02-2010, 10:19 AM
Damn! Who had to flip the switch for the first time? Let me guess, the drill was left on and with everyone out of the way someone, at distance, plugged in an extension cord.

rock~

bob ward
01-02-2010, 10:43 AM
I'm puckering just looking at the photo.

Carld
01-02-2010, 10:50 AM
The dangerous thing is, who had to stand close to it while it did the job? How did you or did you counterbalance that beast?

John Stevenson
01-02-2010, 11:18 AM
Why is it dangerous ?
OK so it's rotating but so is a 4 jaw chuck as an example.
It can't fly out the chuck as it a screwed shank fitting. The top slide can't fly off as it's held by the screw and the gib clamp screws.

If you are within the radius of the tool it's dangerous, if you are outside the radius it's not, but this applies to all rotating objects.

Because of the radius of the cutting tool and peripheral speed the revs have to be kept low. If this was set running at say 500 rpm there could be an issue with out of balance forces, just ike running a big 4 jaw with a lump hanging out.

What's the difference ?

.

Duffy
01-02-2010, 11:36 AM
Sir john;- I know it LOOKS big, ugly and out-of-balance, but estimating from the scale at the top of the photo, it is about a 6" diameter groove. Being a dedicated coward, perhaps 50 rpm and a few thou advance per revolution and I THINK it would work a treat. But what do I know-I am just an amature. Duffy

j king
01-02-2010, 12:35 PM
Looks fine to me John. : )
I went to a job site and had to machine 2 boss pockets inside a 72 inch housing. I had to use a 8" boring bar thru the axis with a milling head mounted on the tool slide sticking out there! Feed it with the bars rotation with a super slow drive. I have to admit I was nervous as the tool was about to make contact. Worked fine tho.. Oh, forgot to add that it was a 1 1/2 end mill 6" long!

Your Old Dog
01-02-2010, 12:40 PM
You fishing? :D I'm betting he's too classy to take your bait !!

j king
01-02-2010, 12:45 PM
No, Lol!

Just adding that there are crazy type things that work but look scarey.

Scishopguy
01-02-2010, 12:52 PM
The only thing that I can see that might pucker one's bum is the magnetic drill on the plate driving it, but John said that they also clamped it in place. No problem...rock on!

Your Old Dog
01-02-2010, 01:03 PM
No, Lol!

Just adding that there are crazy type things that work but look scarey.

LOL I was talking to Sir John, 3rd Earl of Sudspumpwater!

John Stevenson
01-02-2010, 01:10 PM
You fishing? :D I'm betting he's too classy to take your bait !!

No this was prompted by a thread on another group and I remembered this lurking in the back of the cupboard so dug it out and took a pic.

Only ever got used twice but both times it was a life saver.

.

J Tiers
01-02-2010, 03:36 PM
I'm thinking that was a VERY large mag drill...... Most I have messed with wouldn't clear the tool, let alone the slide screw handle.

if the clamping came loose, it surely would have thrashed around a bit....... I'd have put on a couple more extra clamps!

boslab
01-02-2010, 05:21 PM
Its probably safer than the thing that you think IS safe, bet you will ignore a brand new big ol inserted tooth cutter, or a nice big drill bit? them be the buggers that get you, if you look at somthing and it looks a bit dodgey you will treat it with the respect ALL rotating cutters deserve, and truthfully you will be safer for it
And it got the job done, that dosent mean i'd have the confidence or ability to do it, but i have the advantage of another job besides machining, if i cant do it i have the luxury of a machine shop the size of a football pitch that usually has the kit to do it, different at home or when theres nothing else available, thats when it gets interesting!, we have all been there, how the hell can i do this?, its great when it works but its good to treat these machines with respect, they dont usually take prisoners and will ensue swift retribution upon the unwary!
happy new year
mark

nheng
01-02-2010, 05:51 PM
John, May I please borrow it? I want our EHS girl to run out of the building screaming, never to be heard from again :D Den

rockrat
01-02-2010, 06:01 PM
Now dont mistake my post for something it may not be.

His setup is large and a bit daunting, but I do agree that with low rpm's it is fine. I was more jesting than anything. It does look big and a bit crazy but if it got the job done, everyone is safe and no machinery was destroyed, who am I to say otherwise?

Thanks for sharing Sir John. Some days we say, what ever it takes short of loosing a finger.

humble peasant rockrat~

doctor demo
01-02-2010, 10:05 PM
Thanks for sharing Sir John. Some days we say, what ever it takes short of loosing a finger.

humble peasant rockrat~
So if You lose a finger (a thumb in My case) and they put it back on , does that still count as a loss?

Steve

Black_Moons
01-02-2010, 10:16 PM
doctor demo: No that counts as a found not a loss. as in
'Ahhh crap I lost my finger on the bandsaw!.. Ahh nevermind found it, its over here in the corner of the shop'

rockrat
01-02-2010, 10:17 PM
So if You lose a finger (a thumb in My case) and they put it back on , does that still count as a loss?

Steve

Did they put it back in the right direction? That makes all the difference and could cover the spread on a given bet.

rock~

edit,

'Ahhh crap I lost my finger on the bandsaw!.. Ahh nevermind found it, its over here in the corner of the shop'

Aw crap, I'm laughing so hard I'm crying.

rock~

hojpoj
01-02-2010, 10:18 PM
So if You lose a finger (a thumb in My case) and they put it back on , does that still count as a loss?

Steve

Probably not, but they might allow for accelerated depreciation. ;)

snowman
01-02-2010, 11:08 PM
That really makes me miss a good quality mag drill.

I loved that damn tool.

goodscrap
01-27-2013, 04:36 PM
I saw this on UK ebay and though of Sir John's set up as above, though on further reading looks as though the cutter can revolve and perhaps can the whole slide/head?

http://www.ebay.co.uk/itm/Milling-machine-attachment-/111003801858?pt=LH_DefaultDomain_3&hash=item19d8579902

http://i.ebayimg.com/t/Milling-machine-attachment-/00/s/MTIwMFgxNjAw/$(KGrHqJ,!qgFCrurgTgQBQ+WheNc1!~~60_12.JPG

Brian

Toolguy
01-27-2013, 05:26 PM
That looks very similar to the head on a Kearney Treker die mill. Those mills have a rotating part right above the spindle so you can offset the spindle and mill circles and/or angles without ever moving the workpiece.

John Stevenson
01-27-2013, 06:11 PM
No that's better / safer than mine.
Probably a Volstro head

One slide can extend the radius the other other [ handle just visible top right ] rotates the tool around.
The chuck spins but not the tool.

darryl
01-27-2013, 06:27 PM
Replace that handle with a disc and it'll be adjustable on the fly. :( :)

Circlip
01-28-2013, 04:07 AM
Never ceases to amaze how some think it's safe to entrust a twelve year old with a lawn tractor, use a drill chuck to hold a milling cutter and we won't go down the gun alley but don't understand that every job doesn't need teararseing. :rolleyes:

Regards Ian.

John Stevenson
01-28-2013, 03:11 PM
I saw this on UK ebay and though of Sir John's set up as above, though on further reading looks as though the cutter can revolve and perhaps can the whole slide/head?

http://www.ebay.co.uk/itm/Milling-machine-attachment-/111003801858?pt=LH_DefaultDomain_3&hash=item19d8579902

http://i.ebayimg.com/t/Milling-machine-attachment-/00/s/MTIwMFgxNjAw/$(KGrHqJ,!qgFCrurgTgQBQ+WheNc1!~~60_12.JPG

Brian

Sold today, made 128 then, been a Volstro it would have been 528 or even more.

metalmagpie
01-28-2013, 07:56 PM
I used to work in Seattle's shipyards back in the '70s. We never could stand around without someone yelling at us. One day I saw two old machinists sitting comfortably in folding lawn chairs smoking cigars with a satisfied look on their faces. This was so shocking to me that I stood there trying to figure out how they were getting away with this outrageously lazy behavior. Then I realized that the machine they had cobbled up was line boring the huge support bushing for the propeller shaft, just in front of where the prop is located. The boring arm had to be at LEAST 3 feet long, and it moved quite slowly as you can imagine to get the correct cutting speed way out at its end. Each time it came around to the bottom it ticked a star wheel and advanced a few thousandths of an inch. I realized this was an enormously precise and critical job, and that was why the Navy brass was letting these two old guys sit around. But that boring bar setup put Sir John's big facing head to shame! - metalmagpie

WAS Jr
01-28-2013, 08:14 PM
Sir John, I don't understand what the center drill on the bottom of the toolholder does, unless it is just there to prop it up for the picture. Bill S

Circlip
01-29-2013, 03:14 AM
It's a piece of round HSS wiv the end ground for treppaning. Like a parting tool. See original post, O ring grouve

Regards Ian