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franco
08-17-2001, 02:35 PM
Spin Doctor.

Watts Drill.

franco

Cat_Designs
03-03-2006, 02:28 PM
I need to make a new knob for an old altimeter (1920s vintage) but I don’t know how to make a square hole.

The altimeter has a 1/8th inch square post (coming out of the case) that is taped for a small screw to hold the knob on. I can make the round knob but I don’t know how to cut a square hole into the knob about 1/8th inch deep. I’m assuming I should be working in brass as the post is brass (I think). All I have is a lathe (1940’s vintage) and a small drill press. Any suggestions?

Thanks

Chris

SGW
03-03-2006, 02:43 PM
A few ideas. One, you might try to "borrow" a square hole of the right size, from some other part, that you could insert into a larger drilled hole in the knob. You may be able to buy a "square hole sleeve" of the correct size. Check www.reidtool.com (http://www.reidtool.com) to see if they have any. I know they have square hole sleeves, but I'm not sure they go down to 1/8".

As far as actually making a square hole. If it's a through hole, you could try filing out the corners of a round hole with appropriate needle files.

Or, make a square hole broach out of drill rod. Machine (or file) a 1/8" square on the end of a piece of maybe 3/16" drill rod, with the square section being maybe 1/4" long. Put it in the lathe and countersink the end just a bit so it forms sort-of cutting edges on th end. Heat up with a torch and quench to harden, then align with a pre-drilled 1/8" dia. hole in the knob and press in with your drill press quill to plane out the corners.

Getting the broach aligned with the hole may be a little tricky on a drill press. Unless it's aligned really well it will want to go off to one side or the other.

garyphansen
03-03-2006, 02:43 PM
Drill a 1/8" dia hole deeper than you need the square hole. (For chip clearance) Then press a piece of 1/8 square keyway stock into the hole to broach the hole square. (Beleive it or not there are special drills that drill square holes but I do not know if they come that small and it would not be worthwile to buy one for one hole.) Gary P. Hansen

Your Old Dog
03-03-2006, 03:07 PM
Don't rule out 5 minute epoxy. Many a $1000 custom knife is held together using this stuff. You can mix some lamp black with it for a black color. It has the benefit of not getting brittle.

another option. hammer form a piece of round brass tubing onto a square mandrel. Then, drill a hole in your know, insert the squre tube and solder in place. Should hold till hell won't have it.

edited to add:

if you need to remove it just heat knob lightly with propane torch and the epoxy releases it's grip.

[This message has been edited by Your Old Dog (edited 03-03-2006).]

Joel
03-03-2006, 03:19 PM
Another possibility is to drill a hole that just clears the square and use a set screw to retain the knob on one of the flats of the shaft.

Mike Burdick
03-03-2006, 03:19 PM
Okay, a 1/8-inch square hole 1/8-inch deep, right? This is how I would do it with the tools you have. Actually all you need is the lathe.

Chuck up a brass knob blank in your lathe and drill it all the way thru with a 1/8- inch drill bit. Then turn the material around in the chuck and drill or bore another hole about .250 (or whatever) to within 1/8-inch of coming thru. File, or broach, the remaining material square. Then make a brass plug for a press fit into the .250 hole. Machine outside to desired shape.

________________________


[This message has been edited by Mike Burdick (edited 03-03-2006).]

Cat_Designs
03-03-2006, 05:54 PM
All excellent ideas. I recall seeing some small brass square tubing at the Hobby store may try that and some epoxy in a round hole. I think I will try all of the suggestions just to see how well they work.

Thanks again
Chris

Evan
03-03-2006, 06:12 PM
I had to make a winding key for a table clock years ago. It needed a square hole about that size. Keep in mind the hole doesn't have to be entirely square, just enough corners to make it hold. I drilled a hole a bit under the diagonal dimension and ground the shank of an appropriate drill bit square. Tapped it in and voila, square cornered hole.

Oh yeah, the drill is a bit difficult to get back out but I will leave that as an exercise for the readers. http://bbs.homeshopmachinist.net//biggrin.gif

[This message has been edited by Evan (edited 03-03-2006).]

Leigh
03-03-2006, 06:40 PM
Use a square drill. Yes, they do make such things. They consist of a hollow square-cornered broach with a drill running through the center.

Illustration and discussion on Wikipedia http://en.wikipedia.org/wiki/Mortiser

------------------
Leigh W3NLB

[This message has been edited by Leigh (edited 03-03-2006).]

Cat_Designs
03-03-2006, 08:15 PM
Yes, but they are for wood. I don't think it would work in metal. or would it? I know wood working not metal working so I'm clueless on most of this. My new(to me) 1940's lathe is my first step into the balck art of metal working......

I'll let you all know how the the square hole turns out.

Chris

Leigh
03-03-2006, 08:33 PM
Hi Chris,

I saw some in a catalog a couple of years ago that implied they would work in metal, but I don't remember the details. Couldn't find them with Google, but that's probably because I got so many hits (over 14,000) that I got tired of clicking on links.

I would suggest making a brass bushing with the hole in it. Then make the knob, drill a hole large enough for the bushing (without penetrating the knob front), and solder the bushing in place. Pretty simple exercise.

For something this small, I would drill out a clearance hole then file the corners square. It would only take a few minutes in brass. You can buy 1/8" square push broaches, but they cost $90. (McMaster-Carr http://www.mcmaster.com catalog page 2398 in the middle)

Another option: Make the knob in two pieces, with the front separate from the rear, which has the square hole in it. The above suggestions regarding the hole still apply, but the bushing is now the entire rear of the knob, so no hole is required to accommodate it.

I expect the screw was originally an oval head, which fits in a counter-sunk hole but provides a rounded face rather than the more common flat version.

------------------
Leigh W3NLB

[This message has been edited by Leigh (edited 03-03-2006).]

Mcgyver
03-03-2006, 09:03 PM
laying out and working carefuly, you can file a square hole with some needle files. use blue and fit to the square male piece. you can do amazing stuff by fabrication -thats the ticket if its a blind square hole. file the square hole in a small cylinder and soft solder or silver solder into a counter bore. i think basically what Mike said but i may be picturing this piece differently. take some pics, hope that helps

Dr. Rob
03-04-2006, 02:28 AM
Rotary broach, aka wobble broach. Drill square, hex, polygons all day long. Tight tolerances and bottom holes too.

Make your own. Article in HSM a few years ago, or invent one yourself with a ball bearing and some welding.

NSB
03-04-2006, 05:49 AM
This link might be of some use :-

http://www.watchman.dsl.pipex.com/two-legged%20parser/parser.html

Your Old Dog
03-04-2006, 07:10 AM
Another way that may be similar to what others are saying is to:

drill a hole thru some 1/4" flatstock brass. Use files to make it square which isn't all that hard or time consuming. Then take another 1/4" piece of and silver solder it in sandwhich fashion. Mount it on an arbor and true it all up on the lathe.

This came to me like an ephiphany after reading McGyvers post http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif

Evan
03-04-2006, 08:04 AM
Just about every idea proposed here will work. I like the idea of building up the hole from flat material then turning. That would be useful when a truly square hole is required. In this case you don't really need to go to that much trouble. Here is the key I made maybe 15 years ago. I kept the drill bit, you never know when you might need to make something like this again...

http://vts.bc.ca/pics/squarehole.jpg

Spin Doctor
03-04-2006, 08:30 AM
Square hole drills work by having a square guide plate (I've used hex ones too) that is mounted on the part being machined. For a square hole a three flute straight flute drill is guided into the guide plate and the lathe turned on. The drill is held in a special holder that allows it to float. The drill contacts three point on the guide bushing at all times. As the work turns the drills contantly adjusts to the guide plate. I wish I could remember the name of the darn things as I would post a link. Ah, found one.

http://www.integerspin.co.uk/polygon.htm

peter08
09-14-2007, 01:40 PM
Square Holes made easy with Rotary Broaching:

http://www.slatertools.com/rotary9.htm

IOWOLF
09-14-2007, 04:45 PM
Yea, you just need the $600 tool to do it.:rolleyes:

lazlo
09-14-2007, 04:53 PM
Square Holes made easy with Rotary Broaching:

Two of the three stock answers that comes up every time someone asks how to make a square hole: the Watts drill, and a rotary broach.

Rotary broaches only work on depths up to 1 1/2 times the broach diameter (and the broaches are small to begin with). So they're good for screw heads, but you're not going to be boring deep square holes. And like IOWolf says, the rotary broach holders are $1200 retail, and you can occasionally find them used on Ebay for $600.

The Watts drill is interesting, but also very expensive, and someone posted a long thread from a gunsmithing forum here a month or two ago, and the Watts drill was very slow, and didn't work well past 1 1/2 times the drill diameter.

The third answer that's usually mentioned, that hasn't been yet: EDM. :)

I think the other answers are a lot more useful: get a round to square adapter from Reid tool, or cut two square channels and weld them together, or bore a circular hole and broach the remainder square...

If you want to try making your own rotary broach, there's an article in the September 2002 HSM: "Make Your Own Socket Head Fasteners with The Brinkerhoff Rotary Broach"
It's a good article, but I noticed that the approach angle is 6 degrees (the Slater Tool broaches are 1 degree), so the hole will taper more than on the commercial tool.

lazlo
09-14-2007, 05:09 PM
Here's the summary of the gunsmith trying to use a Watts drill to make square holes in a receiver. He ended up making a slotting tool and manually shaping the square hole by racking the quill up and down:

http://bbs.homeshopmachinist.net/showpost.php?p=285021&postcount=48

His final comments about the Watts drill:
http://www.homegunsmith.com/cgi-bin/ib3/ikonboard.cgi?;act=ST;f=8;t=17441;st=0


Contrary to what that book said, and perhaps due to using my fixture instead of Harry's chuck, the hole generally gets tighter towards the bottom. Except for one spot that's about .007" beyond where it should be, most of the error consists of metal being left behind where it should not be.

At this point, my verdict is that we will not be able to simply drill a square hole through a block of steel and use it for a falling block action as-is. The drills and guides are expensive enough that most people would probably not get their money's worth out of them for roughing purposes, either. If you have the ability to finish-cut the hole from this condition, probably you could use the same technique to make one or two square holes directly from round holes. Perhaps if a guy anticipated making 10 or 20 falling block actions in his lifetime, AND had a more powerful mill available, then this could be a worthwhile way of roughing the holes to close to the finished size.

This was from the discussion on square holes here at the end of May:

How to Cut a Pocket with Square Corners? (http://bbs.homeshopmachinist.net/showthread.php?t=23221)

S_J_H
09-14-2007, 05:12 PM
The rotary broaches and holders don't look to terribly difficult to make though, at least at the hobby level for occasional use.
I'll be taking a crack at making one .... one of these days. :D

Steve

IOWOLF
09-14-2007, 06:16 PM
It does have a wobble feature to it that may be difficult to copy.

S_J_H
09-14-2007, 07:28 PM
oh they do wobble? I thought it was just the 1 degree angle(2 degree included) difference of the rotating part - rotating broach that created the cutting action with axial force applied. If there needs to be some sort of wobble motion also then I'll take a pass at that project.

Steve

lane
09-14-2007, 09:14 PM
Every one else put in their 2 cents. So here is mine .
If like you said you have a lathe you probably have a 1/8 square piece of tool bit rex 95 or something smiler. take a piece of 3/8 stock about 1 1/2 inch long drill a hole in it about 3/4 inches deep that the tool bit will slip in to . mix up some J B weld and fill hole insert tool bit let set over night . on bench grinder grind face of bit flat and gripping round part insert in to drill chuck in tail stock of lathe . Drill hole in the knob you wont to broach a little smaller than across the corner of the 1/8 broach. Put lathe in back gear spindle not running and slam tail stock in to knob retract and do it a few more times .You can make any kind of hole you want in any thing up to about 3/8 inch hex ,square are what ever Brass and alum. are easy can do steer but a little harder. Just make up your broach. I use Allen wrenches cut off for hexes all the time .

lazlo
09-14-2007, 09:47 PM
Put lathe in back gear spindle not running and slam tail stock in to knob retract and do it a few more times.

That's basically the drill round hole and broach it square method that Evan mentioned in his first post, but dang Lane -- I don't think I'd want to do it by slamming the tailstock into the workpiece! :)

Seriously, I've just used an arbor press, or even just tapped the square broach in with a hammer, like Evan suggested. To each, his own :p

J Tiers
09-14-2007, 11:04 PM
With this.

Some people don't know that you are supposed to have a hole there before starting the watts drill.

http://img.photobucket.com/albums/0803/jstanley/watts1s.jpg

lane
09-14-2007, 11:27 PM
Lazlo it wont hurt a thing . Lathes are tough.

J Tiers
09-14-2007, 11:51 PM
OK, so I read the "Fuzzbean" thread......... That was a freaking waste of time.....

The guy does not use the floating holder.

He DOES use a high mass 'floating table" which does not work the same way, and definitely DOES weigh a LOT more than the moving part of the drill holder.

He then uses a tiny mini mill to drill the large holes.

He gets bad results, very slow action, and seems to condemn the drill that he used incorrectly, without the correct tooling, on a too-small machine.

What part of that makes sense?

lazlo
09-15-2007, 12:01 AM
Jerry, I thought you were still looking for the Watts floating holder (which is very expensive)? Have you gotten yours to work? If so, could you post some holes you've bored with it?

The reason the Fuzzbean thread was so interesting (to me anyway) was that Watts drills were always mentioned as a machinist Urban Legend, but no one had ever seen one work, let alone how well it worked.

I agree with the problems associated with using a Mini-Mill to drive the Watts drill, but Fuzzbean's floating table design is pretty clever, and seems like it should be just as effective as allowing the head to float, like with the "authentic" Watts floating holder.

According to Fuzzbean's comments, the problem is that the Watts drill, unlike a true Reuleaux Triangle, just randomly bangs around inside the square template, so the metal removal is completely arbitrary. And the deeper the hole gets, the further the Watts shank (which is the part being constrained by the square template) is from the cutting tip, and the hole starts tapering off.

Even Harry Watts himself says you can't drill deeper than 2x the drill diameter with a Watts drill...


Harry tells me that the maximum recommended cutting depth is twice the size of the square,

The drills are $100 each, the square templates are $70 each, and the Watts floating toolholder is $340. Sinker EDM is looking more practical :)

http://www.homegunsmith.com/cgi-bin/ib3/iB_html/uploads/post-8-53884-DSCN3936.jpg

lazlo
09-15-2007, 12:04 AM
By the way, if anyone wants to try making a Reuleaux (or Watts) drill themselves, Fuzzbean posted a scan of what looks like an old Popular Mechanics article on how to make one:

http://www.homegunsmith.com/cgi-bin/ib3/ikonboard.cgi?;act=Attach;ID=11847;f=8;t=17441;p=1 44456

J Tiers
09-15-2007, 09:24 AM
I think there is a rather fundamental difference between a big heavy table with workpiece and a moving drill in a far lighter holder.

Then also, the drilling of deep holes with ANY drill is often problematic. With a specialty drill, I would suppose that not to be magically different.

Fuzzbean used the drill without an essential part of the drilling system, in an underpowered machine, to drill a hole much deeper than the inventor recommends, and he got a bad result.....

Remind me again why we should be surprised at this, and why we should judge the system by that result?

Sinker EDM was not exactly a thriving portion of the business in 1914 or whatever.....

J Tiers
09-15-2007, 10:49 AM
OK, here it is...

This hole may have taken 8 minutes, drilled just recently this morning after prior post, including setup, a slippy flat belt, cleaning said belt, and drilling the original round 5/16 hole, plus interruption by wife. It is a 1/2" square, and measures about 0.504 square, 0.550 deep.

I drilled in in the end of a piece of bar in the lathe because I have a setup for that.

http://img.photobucket.com/albums/0803/jstanley/watts1a.jpg

http://img.photobucket.com/albums/0803/jstanley/watts2.jpg

http://img.photobucket.com/albums/0803/jstanley/watts3.jpg

http://img.photobucket.com/albums/0803/jstanley/watts4.jpg

J Tiers
09-15-2007, 10:50 AM
Ran afoul of snippy forum rules about attachments and time between posts.....

Here is the last

BTW, the drill is not particularly sharp, I did hone it slightly before starting. Material is 1018. Lathe has 1/3 HP 3phase motor drive, direct via flat belt for this job.


Showing slight burr on edge

http://img.photobucket.com/albums/0803/jstanley/watts5.jpg

TGTool
09-15-2007, 01:43 PM
It does have a wobble feature to it that may be difficult to copy.

It doesn't actually wobble in the way we think about loose fits wobbling. The centerline of rotation for the tools is at an angle to the centerline of rotation of the lathe. Since they're both rotating together once the tool contacts the work, it means that each corner of the broach contacts the work in turn essentially nibbling out the shape. That means that the broach tool then needs to have a back clearance of the offset angle plus a little.

Since they have the angular CL they also need a means to be set transversely a little to line the broach up with the hole center for tools of different lengths.

I've seen them made in a home shop kind of like a live center, but with a toolholder cavity instead of the 60 degree plug.

Your Old Dog
09-15-2007, 02:05 PM
..........p.f.s. ;)

IOWOLF
09-15-2007, 02:08 PM
They wobble the way I think they wobble,Your definition of wobble May vary.

lazlo
09-15-2007, 05:23 PM
OK, here it is...

This hole may have taken 8 minutes, drilled just recently this morning after prior post, including setup, a slippy flat belt, cleaning said belt, and drilling the original round 5/16 hole, plus interruption by wife. It is a 1/2" square, and measures about 0.504 square, 0.550 deep.

Nice job Jerry -- thanks for the pictures!

Did you find the floating holder on Ebay?

I was outbid by RKepler (Russ, here and on PM) on a complete Watts set about 2 months ago, but then again, he seems to outbid me on a lot of stuff :)

J Tiers
09-15-2007, 05:30 PM
nope, got it at a sale.....

You do NOT want to know what I paid for it, but it was not much.

I think Fuzzbean just didn't go at it the right way. It is easy to use, and not even as noisy as you might think.

The floating table is no substitute, the holder is just a buzzin' around in the hole and chips come pouring out. Slower drilling than with a twist drill, but not by a lot.

The idea of a "random arbitrary" path seems wrong. I don't have any slow motion video of the actual holder and its movement, but the "impression by eye" is that a consistent path is taken by the drill. The tool marks at the bottom of the hole seem to confirm that impression. And I don't see how it could be avoided, since the ruleaux triangle only barely rotates inside the square.

BTW: the drills work a LOT better when the swarf can escape easily, as in a lathe. In a DP, the swarf would seriously compromise the operation, as the drill has no ability to move it out of the hole.

TGTool
09-15-2007, 09:38 PM
They wobble the way I think they wobble,Your definition of wobble May vary.

Okay, maybe I'm a sucker, but how do YOU think they wobble? I'm open to explanations.

J Tiers
09-16-2007, 01:08 AM
Looking again at square holes I have drilled, I see a little of the effect Fuzzbean mentioned, the non-square hole. But it is just a very thin spot on the bottom.

I think the problem with the "left material" in Fuzzbean's holes may have been due to a problem with the pilot hole. He mentioned making a change in the pilot partway in, and it may have been there.

I drilled in square until I almost had no pilot hole left, just a little dimple. And, I noticed that the very bottom of the hole has just a thin uncut area that looks like his. On this hole it is only about a 0.010 "layer" on the hole bottom.

The effect is a slight "bulge" inwards in the middle of all 4 sides.

But since this uncut area is so thin, on the very bottom of the hole, it may be just that the drill as it was sharpened (by a hack, it looks like) tends to cut like that at first, and cleans up if you keep drilling. If so it would always have the exact same effect on the bottom surface of the hole, but it would not be present any further up.

it may be coincidental that the pilot hole was petering out. I just don't know.

I do know I don't see the effects he mentioned in the "body of the hole", nor does it take anything like the amount of time he took with his method.

I am forced to assume that the holder does the "magic".

peter08
09-18-2007, 05:30 PM
The wobble in a rotary broach is really only visible when the holder is turning. Rotary Broaching works when a spindle is turning the broach holder OR the material. When the material is turning, no wobble is required because the 1 deg. angel is held by the broach holder. You can see this in the Slater video: http://www.slatertools.com/video.htm.

However, when the the material is stationary, and the holder is in a mill spindle for example, the head of the holder (which is offset at a 1 deg angle) appears to be wobbling because it is not perpendicular to the work. The head is not in line with the shank of the tool. Actually, it never really wobbles at all. Notice how sharp the corners are compared to the Watts though.

http://www.slatertools.com/images/aluminum-broach-sample.JPG

franco
09-18-2007, 10:21 PM
lazlo,

Some time ago MEW magazine had an article on the Watts type drills which discussed the working principle and gave some information about a floating head and drills made by the author. If you are interested in seeing this drop me a PM with an e-mail address and I'll send you a copy - there are three pages, two of around 160 KB and one about 100KB.

BTW he comments that squares cut with the drill have slightly rounded corners, but on polygons with more than four sides the corners are sharp.

Don't know how I show up as the original poster in this thread - that post is quite old, and was answwering another question!

franco

Peter Neill
09-21-2007, 03:16 AM
Coming to this a little bit late I know, but I remembered seeing a short video of this being done in the home workshop with some home-made equipment.
This was following up on a short article in MEW.

Took me a while to find the link to it, but the clip can be found on the web page page below, and the one to look at is " percage trou carre. avi ".
There are 2 clips both exactly the same.

Link: http://maurel.meca.free.fr/Telechargement/

Peter

lazlo
09-21-2007, 12:41 PM
Wow, that's a neat video Peter! First time I've actually seen a Watts drill at work :)

Did the HSM article include how to build the floating tool holder?

A lot of the floating reamer holders have a two-way dovetail, which allows the head to slide in either the x- or the y-axis at a time, but it seems like that would give the Watts drill a strange stair-step movement through the square template. I guess that doesn't matter, since the movement is totally random, and you just keep drilling until all the material is gone.

Jerry: on your Watts-brand toolholder, is the float constrained to one axis at a time, or is it one of the fancy ball-bearing guides that allow movement in any direction?

Peter Neill
09-21-2007, 01:18 PM
Lazlo, my mistake, it was Model Engineer, not MEW.
It was in Vol. 197, issue 4285, 27 October -9 November 2006.

It's a 5 page article, complete with all drawings needed to make the tooling.
Worth getting hold of a copy if you can, if not, then drop me a pm.

Peter

lazlo
09-21-2007, 02:06 PM
Lazlo, my mistake, it was Model Engineer, not MEW.
It was in Vol. 197, issue 4285, 27 October -9 November 2006.

Doh. Model Engineer is Unobtanium in the US. I'll check Ebay...

J Tiers
09-21-2007, 08:33 PM
Was there a video at the URL mentioned? Because whatever was there was NOT any video of any drill, that I can tell you. Just a bunch of funny patterns on the screen. Time to shut down and run virus-scan

The holder goes anywhere anytime. It seems quite free.

I do not believe it is in any way random....

That is just fuzzy-bean's idea, and we already know that he DOESN'T know diddly. The idea of it taking 4 hours to get a hole with the drill is insane, and bears no relation to any reality.

The movement seems to my eye to repeat the same path.

The marks at the bottom of the hole suggest that it repeats the same path.

BadDog
09-21-2007, 09:03 PM
The funny patterns were probably just the default "ambiance" animations used for audio. WM and some others default to those images when they either don't have the video codec, or if the data is not properly formatted. So you wind up with audio, and "funny patterns" for the video. Not a virus or anything of the sort...

lazlo
09-21-2007, 09:27 PM
Was there a video at the URL mentioned? Because whatever was there was NOT any video of any drill, that I can tell you. Just a bunch of funny patterns on the screen. Time to shut down and run virus-scan

The video works fine Jerry -- why would I compliment the video Peter posted if there wasn't any? :rolleyes:
Like BadDog says, you're missing a codec -- it's not a virus.


The holder goes anywhere anytime. It seems quite free.

That's my definition of random :)


I do not believe it is in any way random....

That's why I was asking about the floating toolholder -- whether it was arbitrary free floating, or separately free-floating on the X- and Y-axis' like most floating tap holders.

If the Watts toolholder somehow allows truly free floating (i.e., the holder can move in arbitrary diagonals), then I would think the motion of the drill is truly random, since there's nothing constraining the drill in any particular path.

A Reuleaux Triangle (which the Watts drill is not) traces a square outline when the center axis follows a circular arc, but that's a different process:

http://www.homegunsmith.com/cgi-bin/ib3/iB_html/uploads/post-8-51593-reuleaux.gif

lazlo
09-21-2007, 09:50 PM
I remembered seeing a short video of this being done in the home workshop with some home-made equipment.

the clip can be found on the web page page below, and the one to look at is "percage trou carre.avi".

Link: http://maurel.meca.free.fr/Telechargement/

Thanks for that link Peter -- that guy has some really neat videos.

Look at the eccentric cams he built here:
http://maurel.meca.free.fr/Telechargement/engrenage-paradoxal123.avi

...and here:
http://maurel.meca.free.fr/Telechargement/engrenage-paradoxal222.avi

Jerry: I ran GSpot on the home-made Watts drill video -- it uses the 3ivx (MPEG4-based) codec. You can download it here:

http://www.free-codecs.com/download/3ivx.htm

J. R. Williams
09-21-2007, 10:38 PM
What's wrong with using a forge to heat the part and driving a square punch into or thru the part? The old blacksmiths had this mastered.

JRW

J Tiers
09-21-2007, 11:01 PM
media flailer went out and got the codec, still no video. Pogga-pogga.

Random? Nope...... I think you forget that the holder requires the drill to rotate. And it also has a guide plate. The drill size is related to the guide plate size.

A much smaller drill WOULD probably randomly bounce around. But a moment's thought will show that the right size drill will NOT do that.

The drill goes around in a repeating pattern as the "edge" hits the side, and forces the drill to swing, then rotates along the side, and repeats as the next edge hits the guide. There is a rotating path around the square.

You can easily see the principle as you rotate the drill by hand in the guide. The drill very naturally takes a rotating path that travels around the square.

I do NOT think you can call that random.

The marks on the bottom of the hole CONFIRM the regular path. Instead of random scratches, they are a pattern that is the same at each side of the hole.

Sorry, but ol' fuzzy-bean has it completely wrong. I think his comments were influenced by the fact that he USED THE DRILL INCORRECTLY, had very poor results, and then cast about for explanations. He is "enthusiastic" but not what I would call "scientific" in his trial and discourse.

For the totally wrong way he used the drill, his explanation may BE right. But it has NOTHING at all to do with the practical use of the Watts drill system as designed.

For all those who think it is totally random "drunkard's walk" and a bad system, you should be aware that the holder , drills and plates contain mercury, PCBs, and other known carcinogens and lethal substances. I will take that hazardous Watts drill stuff off your hands as a public service, no charge. :D


OK, finally saw the video.....

It totally confirms the regular movement and path. Right at the end where it slows down, you can see that clearly

lazlo
09-21-2007, 11:38 PM
What's wrong with using a forge to heat the part and driving a square punch into or thru the part? The old blacksmiths had this mastered.

That was suggested earlier, and I agree J.R. -- broaching it is a much more practical way to make a square hole. Aside from simplicity and low (virtually no) cost, it doesn't have the depth limits that the Rotary Broach and the Watts-type drills have (about 1.5 - 2x the drill/broach diameter).

lazlo
09-21-2007, 11:51 PM
Random? Nope...... I think you forget that the holder requires the drill to rotate. And it also has a guide plate. The drill size is related to the guide plate size.

The drill goes around in a repeating pattern as the "edge" hits the side, and forces the drill to swing, then rotates along the side, and repeats as the next edge hits the guide. There is a rotating path around the square.

You should read the article from the old Toolmaker's Handbook (or maybe it was an ancient Popular Mechanics) that Fuzzbean posted describing how the Watts drill works. I posted it earlier in the thread:

http://www.homegunsmith.com/cgi-bin/ib3/ikonboard.cgi?;act=Attach;ID=11847;f=8;t=17441;p=1 44456

After describing the Reuleaux Triangle, and how a Watts drill (with equilateral cutting blades) is different, they explain:
"If the [Watts-type] drill is made with sharp corners, straight sides, and a flat cutting face, it will not act like a regular drill with the cone-shaped profile of its self-centering cutting edges. A cone-shaped cutting profile would cause the drill to seek its center of rotation automatically. With the cutting edge in a flat plane, however, the drill is allowed to wander in whatever direction the cutting forces dictate."


OK, finally saw the video.....
It totally confirms the regular movement and path. Right at the end where it slows down, you can see that clearly

It's a low resolution video in a dark room -- how can you possible see whether the Watts drill, which is nearly perpendicular to the view angle, is banging randomly off the edges of the square jig as it rotates, or orbiting in circles?! :)

J Tiers
09-22-2007, 12:00 AM
You should read the article from the old Toolmaker's Handbook (or maybe it was an ancient Popular Mechanics) that Fuzzbean posted describing how the Watts drill works. I posted it earlier in the thread:

It's a low resolution video in a dark room -- how can you possible see whether the Watts drill, which is nearly perpendicular to the view angle, is banging randomly off the edges of the square jig as it rotates, or orbiting in circles?!

1) I have the book from which the article comes......

2) you can easily see the motion of the holder as the spindle slows. The video seems quite light enough to see details and the motion. It is quite clear that the holder is moving "around" a center.

3) if you have a drill and simply spin it held in the hand while inserted in the square guide, it is again very clear that it 'wants to" move in a regular orbital path.

4) the pattern of tool marks in the hole absolutely show the regular orbital path.

Sorry, but "fuzzy-bean" is FOS on that. But we already knew that, after reading his goofy posts........

Four hours? Oh, puh-leeese..........

lazlo
09-22-2007, 12:15 AM
1) I have the book from which the article comes......

So you read the part that I posted above about the motion of the cutter being random? :)

"the drill is allowed to wander in whatever direction the cutting forces dictate."

By the way, the book that article comes from is:

"THE COMPLETE MODERN BLACKSMITH" by Alexander G. Weygers.


Sorry, but "fuzzy-bean" is FOS on that. But we already knew that, after reading his goofy posts........

I disagree -- he didn't want to buy the $340 Watt floating tool holder, so he followed the directions in the "Complete Modern Blacksmith" exactly -- it was a clever build, and it should work nearly as well allowing the workpiece to randomly bounce around as it is to allow the toolbit to bounce around.

J Tiers
09-22-2007, 12:16 AM
OK, the best picture of the hole I could easily get. Sorry for the fuzzy pic, it wanted to focus on the upper surface, and the depth of field was not the best. I might try again with a different f-stop if I get around to it.

Another fact.... this particular hole was 'pushed" to the point that the pilot hole is almost totally gone. At that point, the action of the tool is not so good, and it will eventually stop cutting, when the non-cutting center hits bottom.

Despite the above, you can see several features which totally contradict the "random bouncing" opinion..........

there is a regular 4 lobed feature right in the middle.

The tool marks clearly have a 4-way symmetry

Even the scratches indicating the tool path have a 4-way symmetry, and are consistently going in a regular 4-sided path.

So much for "fuzzy-bean".

http://img.photobucket.com/albums/0803/jstanley/watts6.jpg

edit: Picture deleted in favor of one posted below.

lazlo
09-22-2007, 12:29 AM
Jerry, the cross in the center is intriguing -- what makes that? Is that the intersection of the three flutes bottoming-out in the hole? Could you post a picture of the end of the drill tip?

The actual tool cutting marks look completely random...

By the way, here's Harry Watt's 1917 patent. Unfortunately, it's very poorly written and very hard to figure out how he intended for the drill to work:

http://patimg2.uspto.gov/.piw?docid=US001241176&PageNum=2&IDKey=6B4CF8BBDC18&HomeUrl=http://patft.uspto.gov/netacgi/nph-Parser?Sect2=PTO1%2526Sect2=HITOFF%2526p=1%2526u=% 25252Fnetahtml%25252FPTO%25252Fsearch-bool.html%2526r=1%2526f=G%2526l=50%2526d=PALL%2526 S1=1241176.PN.%2526OS=PN/1241176%2526RS=PN/1241176

J Tiers
09-22-2007, 01:02 AM
Jerry, the cross in the center is intriguing -- what makes that? Is that the intersection of the three flutes bottoming-out in the hole? Could you post a picture of the end of the drill tip?

The actual tool cutting marks look completely random...



Can't see HOW you could say the marks are random. Here is a better picture, in which you can CLEARLY see the way the cutting marks follow the square. You can even see how the pattern is starting to break down as the nose of the tool begins to run out of pilot hole.

But the marks very clearly swirl in a square pattern. It just is NOT a question, it's a fact.

If the drill was wandering in a random fashion, there should be cutter marks at every angle, criss-crossing the area with no pattern and no regularity.

Instead, it is clear that the drill follows an orbital path. This is well illustrated by ALL the evidence, both the video linked above, and the tool marks, the evidence of your own hands trying the drill in the hole, etc, etc, ad nauseum.


http://img.photobucket.com/albums/0803/jstanley/watts7.jpg

The swirls stop in the corners, as the drill corner "catches" there and prevents further rotation around the previous center. The drill then rotates around the "caught" corner, until the next corner "catches", by which time the angles are such as to release the previously 'caught" corner. That creates a repeating pattern and NOT a "random bouncing". You can even see the effect of the drill pivoting around the hole corner.

As far as the nose of the drill, it has been shown before, in the very links posted above.

I am tired of taking pics.... but the center is a non-cutting area with a hole in it, much as illustrated in the linked stuff.


I disagree -- he didn't want to buy the $340 Watt floating tool holder, so he followed the directions in the "Complete Modern Blacksmith" exactly -- it was a clever build, and it should work nearly as well allowing the workpiece to randomly bounce around as it is to allow the toolbit to bounce around.

So you "disagree", although you have no evidence.

You may disagree, using Alexander Weygers and fuzzy-bean as your sources. But Alexander Weygers is not necessarily the end-all expert on this, although he apparently made a drill that functioned in some way. I am pretty sure that he has used the extended shank style in the lathe, as that action is known to work. I am far less sure that he ever actually used the "moving table" approach, since the extremely high moving mass apparently messes up the action, as fuzzy-bean found out. Weygers is a good blacksmith, but when he branches out, he seems to be on less firm ground, and often seems to suggest alternatives that he may never have actually tried.

We KNOW fuzzy-bean is not an expert, since HE could not make the drill work in any reasonable time. He used it wrong without an essential part of the system. But on the other hand we KNOW the drill DOES work and works fast, so he simply didn't know how to make it work.

You yourself do not have the drill system Hence you have never used it, and so cannot be an expert. But nonetheless you are still certain it is a random action that takes a long time and works poorly.

If you-all want to believe the drill bounces around randomly, and takes 4 hours to make a hole, then you may do so. It does not hurt me a bit, and probably won't hurt WBTC either.

BUT, do not ARROGANTLY and IN DEFIANCE OF ALL EVIDENCE claim as a "fact" that the action is totally random, slow and troublesome. It may mislead others, who want the facts of the matter.

OTOH, your "opinion" is your own, if it is made clear that it IS only your opinion.

NevadaBlue
09-30-2007, 12:26 PM
Wow, you really get passionate about your skills, don't you. Your replies seem kind of harsh to other members. I thought the reason for forums like this was to have discussion, not to belittle others questions and observations. Strange way to act in public. I hope you have a nice day.

Fuzzbean
10-01-2007, 12:23 PM
I do not believe it is in any way random....

That is just fuzzy-bean's idea, and we already know that he DOESN'T know diddly.

Pleasant forum you guys have here. :confused:

I'd just like to set the facts straight on this matter. If you read through my thread on the gunsmithing site, you will discover that I NEVER SAID THE DRILL CUTS RANDOMLY. Indeed, if you read the Weygers information more carefully, you will see that he never made that assertion either. What he said was that the flat-ended drill WOULD walk around and cut randomly, until the square guide is added, and then the square guide forces the bit to follow a regular cutting pattern.

Also, I never-ever blamed the Watts drill for the problems I had, or asserted that the time it took me was typical of what the Watts drill could do. Here are some quotes taken directly from my thread:


"The real problem is the mini-mill is badly lacking in torque."


"Probably one of those $1000 round column mill/drills could drill this hole in 15 minutes to one hour maximum. Maybe in 5 minutes. "


"Bear in mind that Harry only recommends a maximum depth of twice the hole size. I went three times the hole size here. Probably a gradual loss of the proper shape is inevitable, but in this case things took a dramatic turn for the worse right where I experimented with the 3/4" pilot hole. If I hadn't done that, probably the final shape would have come out considerably better."


Please remember guys, my thread was posted on a site dedicated to building guns from scratch in the home workshop, using minimal tools. Although I've been a professional machinist for over 15 years, I was between jobs at this time and it just so happened that the ONLY machine I had available was a Harbor Freight mini-mill. My thread was intended to be an experiment, to find out if it was possible to get that machine and the Watts drill to do things neither one was designed to do. I discovered what the limits were, and I certainly did not blame Watts Brothers Tool Works in any way for the result.

Fuzzbean
10-01-2007, 12:39 PM
One additional point.

My "floating table" clearly DOES allow the drill to wobble in the correct pattern. The hardened drill just fits into the hardened guide bushing; the drill either moves in the correct pattern, or it cannot move at all.

I attribute the shape problems I had partly to my purposely experimenting with a pilot hole larger than what the Watts people recommend, and partly to eventual wear on the outer corners of the drill but from so much unproductive spinning in the tough alloy steel I was trying to drill. I believe if I used the correct size pilot drill (which I didn't have on hand) and if I ground back the bit maybe 1/16 inch to remove the radiused corners, then the bit would cut a better shape. Assuming I had a more powerful machine to turn it.

I'm not claiming my floating table is as good as the Watts chuck. It is too heavy, as I pointed out in the thread. But cost was a big factor, and I built the table for free from scrap I had on hand. It also fit into the limited "Z" space of the little mini-mill, something I don't think the Watts chuck would do.