Enco/Gamet Boring Head

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asallwey
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Enco/Gamet Boring Head

Post by asallwey » Thu Aug 17, 2017 8:21 pm

I just borrowed an Enco/Gamet automatic boring head. I read the brief manual and still need help. It does not have any model #. I know the holding knurled ring will advance the cutting head. I have no idea what the "Stops" look like the manual talks about. It has 3 socket head screws in the knurled ring. I have no idea what they do.

I want to open part of the center hole, leaving a ledge at the bottom for installing a seal. A Stop would be handy. I could count the clicks (advance of 0.0025" per click), but I would like to make use of the features of this head.

Can anyone help explain how this head works?

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GlennW
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Re: Enco/Gamet Boring Head

Post by GlennW » Fri Aug 18, 2017 6:28 am

asallwey wrote: I have no idea what the "Stops" look like the manual talks about.
The stops are circled.
gamet1.jpg
Glenn

Operating machines is perfectly safe......until you forget how dangerous it really is!

asallwey
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Re: Enco/Gamet Boring Head

Post by asallwey » Fri Aug 18, 2017 8:28 am

Glen,

Looks like I have a different model as I don't have those screws. I take it they are opposite the side with the oiler and gib screws. I guess I will have to count clicks.

I attached some pictures of my head.
+ So another question, what are the screws in the knurled ring for?
+ Can you tell if my head has speed adjustment?

Let me add, my head does not say Gamet, but on the Enco label it does say Made in France.

Alex
Attachments
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GlennW
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Re: Enco/Gamet Boring Head

Post by GlennW » Fri Aug 18, 2017 8:32 am

The stops are used on boring/facing heads to automatically stop the outward or inward movement of the slide at a set position when facing.

I'm not familiar with Gamet heads, so perhaps yours is just a plain boring head and does not do automatic facing.
Glenn

Operating machines is perfectly safe......until you forget how dangerous it really is!

johnfreese
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Re: Enco/Gamet Boring Head

Post by johnfreese » Fri Aug 18, 2017 9:42 am

I have a scan of the manual if anyone is interested.

asallwey
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Re: Enco/Gamet Boring Head

Post by asallwey » Fri Aug 18, 2017 5:22 pm

Glen, mine does have the automatic movement.

John, Is your manual 4 pages long with the 4th being an explosion diagram of all parts? If so I have that one.

ccfl
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Re: Enco/Gamet Boring Head

Post by ccfl » Fri Aug 18, 2017 6:20 pm

Hey, I have one of those! Got it off ebay as an abused basket case, remade all the broken/missing parts and made it functional and pretty again.

There was once a really good page about it here: http://www.schsm.org/index.php/articles ... oring-head
...but it has since gone dark. Luckily I saved a copy while it was still up. Unfortunately the board won't let me upload it as an attachment (.zip of the page and all images), PM me or post your email and I can send it to you.
"Never trust a man who puts a witty quote in his sig line." -Mark Twain

ccfl
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Re: Enco/Gamet Boring Head

Post by ccfl » Fri Aug 18, 2017 6:36 pm

The hex sockets around the knurled ring are cams that raise and engage additional feed ramps. All of them off = one click/feed per revolution, one of them on = two clicks per rev, so on. One of the ramps is fixed and always engaged by default.

For the auto-feed to function, the gib adjustment has to be JUST RIGHT. Also you have to remove any backlash from the vernier. The system has to have some drag or else the leadscrew just bounces back after the ramp passes and the feed never advances.
"Never trust a man who puts a witty quote in his sig line." -Mark Twain

asallwey
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Re: Enco/Gamet Boring Head

Post by asallwey » Fri Aug 18, 2017 7:47 pm

ccfl,

Great! Thanks for the info on those screws in the knurl. Two of them are screws and the 3rd hole must be for a rod.

Am I right in thinking this head doesn't have Stop screws?

ccfl
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Re: Enco/Gamet Boring Head

Post by ccfl » Fri Aug 18, 2017 8:35 pm

They aren't screws, they're eccentrics that lift or lower a feed ramp. They are springy and snap into place either up, disengaging the ramp, or down, engaging the ramp. Try it - flip one one direction and spin the ring, it'll click twice per rev (and advance .005 per rev). Disengage them all and only the single default ramp will be active, and it'll only click once per rev.

The ramps push down on this sticky-uppy bit, which rotates a toothed wheel on the leadscrew. Each tooth = .0025" feed.
Img_2545-.jpg
This is the knurled ring flipped upside down. Rotating the selector(s) in the ring force the ramp down (up in this pic). Mine is the smaller 3" #1100 which only has 2 ramps, the other models have 3 (one fixed, two selectable).
Img_2549-.jpg
Img_2548-.jpg
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ccfl
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Re: Enco/Gamet Boring Head

Post by ccfl » Fri Aug 18, 2017 8:45 pm

The selector on mine was broken, this is the only pic I have of making a replacement. It just positions the ramp so that it either hangs down and whacks the sticky-uppy bit every time it passes, or lets it retract up out of the way and not whack the sticky-uppy bit.
Img_2157.jpg
The one with the smooth hole is the non-eccentric eccentric that keeps the fixed ramp engaged at all times. It's supposedly for a tommy bar, but that seems like not such a good idea unless you want the feed to advance until the slide runs off the end of the leadscrew.
"Never trust a man who puts a witty quote in his sig line." -Mark Twain

asallwey
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Re: Enco/Gamet Boring Head

Post by asallwey » Sat Aug 19, 2017 8:50 am

Ok, your pictures clarify the diagrams in the manual. Yesterday I found got another manual, this one for an Enco head. Both are almost identical in verbage, but the pictures are a little different. The Enco one is a better copy with clearer pictures.

In the first following picture, do you know what are the 4 outer screws for? Maybe just holding internal parts?

Now about those Stops. The center screw above the vernier has a companion on the opposite side. With just quick playing it seems to stop carriage travel. The screw is about 1/2", which I guess would allow sufficient travel for grooves, etc. Are these the travel stops?

If this is the stop screw, how best to use it? Turn the vernier (beginning with carriage fully seated and vernier set to zero) to advance the carriage the travel required and snug the stop screw?

Thank for all the help, very little seems to have been written about these heads.
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