PDA

View Full Version : OK, What's the secret to Knurling?



KiddZimaHater
02-25-2010, 09:02 PM
GGRRRR...
I need to make a knurl on some aluminum parts, but haven't been too successful.
So what's the big secret to knurling?
I first tried one of those "Fixed" knurlers, but the pattern seemed to double-track.
So I switched to a "Floating Head" type knurler. The first attempt came out beautifully. Then on the following parts, Double-Tracking nonsense again.
UUUGGGHHH !!!!
What gives?
The knurler is on center. I have low RPM's. I'm feeding it at .015 per rev.
Plunging in about .01-.015.
Please educate me.:(

Ted Coffey
02-25-2010, 09:08 PM
Start by reading this:
http://www.proshoppublishing.com/articles_knurling.html

goose
02-25-2010, 09:18 PM
So what's the big secret to knurling?



http://www1.mscdirect.com/ProductImages/0906105-11.jpg


3 bills

Gary

Black_Moons
02-25-2010, 09:26 PM
http://www.nolansupply.com/small_images/32965.jpg
0.5 bills, ebay.
+ reading about the correct diamiters.. some go by the correct diamiter school.. others just mash it in really deep and it usally works out.
the ones that put stress on your compound/cross slide etc are not very good unless you have a GIANT lathe, though they do have unlimited diamiter, and can be used ok for soft materials..

Doozer
02-25-2010, 09:28 PM
"Quick" brand knurling tools are also very good.
They have straight knurl wheels mounted at a 45* angle,
that produce the diamond pattern. It actually cuts the
knurl, not just upsets the metal.

--Doozer

http://www.quick-tools.at/raendelfraeser_img/A1-KF.jpg

polepenhollow
02-25-2010, 09:47 PM
Come up to the part w/ the knurl. appx 200 RPM. Feed knurl in w/ r/h as you turn the saddle wheel w/ the LH. Feed towards chuck. Let Knurl wheels come half way off part and then feed to the right until the knurl wheels come off part. Feed left and feed in more w/ the crosslide. Only feed when full knurl is on part..
If you get cross knurl or double knurl, increase the feed speed (LH) on the saddle wheel.
Get rid of the cross or double knurl on the first or second pass, otherwise it may be impossible to remove.
KL

Dr Stan
02-25-2010, 09:56 PM
The floating head is superior to the fixed.

1) Increase your feed rate to about .025"/rev

2) Make sure your knurling tool is good and square with your work

3) Have a good quality knurling tool. If you are using Chinese knurling tools you will probably never get a good knurl.

4) Use some cutting fluid such as Tap Magic or flood coolant to keep the tool and the part flushed. This will keep the "chips" from embedding themselves in the tool and/or the part.

5) Do not disengage the knurling tool from the work until you are done. Feed one direction, stop the lathe, reverse your feed and go back over it. Repeat as necessary increasing pressure on the part until you have a good knurl.

lazlo
02-25-2010, 10:07 PM
Start by reading this:
http://www.proshoppublishing.com/articles_knurling.html

That quote from Machine Shop Trade secrets will pick a fight here. He's a diametral pitch knurler :D

"Following the formula stated previously, 0.060 divided by 3.14159 is 0.019. Therefore, any multiple of 0.019 should provide a diameter for a perfect knurl. "

Ken_Shea
02-25-2010, 10:25 PM
That quote from Machine Shop Trade secrets will pick a fight here. He's a diametral pitch knurler :D

"Following the formula stated previously, 0.060 divided by 3.14159 is 0.019. Therefore, any multiple of 0.019 should provide a diameter for a perfect knurl. "

What/where does the .060 come from?

lazlo
02-25-2010, 10:36 PM
What/where does the .060 come from?

The distance between two teeth on the knurling wheel.

TGTool
02-26-2010, 12:16 AM
"Following the formula stated previously, 0.060 divided by 3.14159 is 0.019. Therefore, any multiple of 0.019 should provide a diameter for a perfect knurl. "

Well no wonder. I'm doing everything wrong! I never measure or calculate a diameter or know what my knurl wheel pitch is. I just mount a straddle knurling tool, the cheap Enco one, get it about centered, tighten the crap out of the nut, run 5 seconds or so to see if it's raising the knurl right and crank some more if necessary. If it's looking good I keep feeding it oil and traverse down the stock for as long as I need a knurl and quit.

So it's my defective methods that are producing such defective knurls. Verrrry interrresting.

http://i48.photobucket.com/albums/f244/TGTool/ExternalHone.jpg

Doozer
02-26-2010, 12:29 AM
I have always had better luck if the knurling tool was NOT square to the work. I point the knurling tool just 1 or 2 degrees towards the direction of travel. This gives the wheels a gradual lead in to the cutting action. A similar concept that allows use of setting the tool square to the work, is to use crowned knurling wheels. Same idea of giving the cutting part of the wheel some approach. Crowned knurling wheels are a but expensive and less common, so I just angle my tool. If you want, I believe J&L has them.

--Doozer

Carld
02-26-2010, 12:31 AM
There is truth to what lazlo is saying. I cut knurls from time to time on different diameters and have found the if I have a hard time getting the wheels to make a diamond if I reduce the diameter some the knurl starts easier. Sometimes it don't take a lot because once the diamond starts it's easy to work it into a good diamond.

I experimented once by taking a few thousandths off and knurling and the diameter changes did make a difference. Most the time I can force a good diamond and when I do I think what is happening is I am eating the metal off reducing the diameter until the diamond starts and then forms up real nice.

Sometimes I start a knurl and get such a fine pattern I get a little disgusted and force the knurling tool in real hard and shortly the diamond starts coming up. Other times it just jumps right out of the surface with little forcing. All this happens on different diameters.

There have been a lot of threads on knurling and several posters profess the correct diameter for the pitch of the knurl wheel and I have began to believe it has merit. It's the only thing that can explain taking a few thousandths off the work and getting a good knurl when it didn't with the original diameter.

I guess this will be argued until the end of time much like the use of SFM charts.

MuellerNick
02-26-2010, 02:56 AM
These are my self-made knurling-heads:
http://www.cncecke.de/bilder/uploadFiles/16348_125_raendel1.jpg

And this is one of the results:
http://www.cncecke.de/bilder/uploadFiles/16348_112571876827_raendel4.jpg

Admittedly, the left part is not perfect.
I never calculate the diameter, because you always get it working. Do not use oil, you will end up with some kind of metal mill. Use flood coolant to wash away all the fine chips.
Simply start with about half the wheel's width in contact and feed in until the pattern "catches up" (no doubles) then move left/right and feed in until the pyramid's tips are closed.


Nick

John Stevenson
02-26-2010, 03:50 AM
Steel, 30mm diameter 15" long, 500 rpm.

http://www.stevenson-engineers.co.uk/files/longknurl1.jpg


http://www.stevenson-engineers.co.uk/files/longknurl2.jpg

No calculation, just go for it.

.

Circlip
02-26-2010, 06:59 AM
Ahh, but you've changed the rules Sir John, THAT bar is a Metric diameter so is nearer to the divisor of 19 thou.than 1 1/4". :D

Regards Ian

Carld
02-26-2010, 08:51 AM
Those are nice knurling tools Nick. Your knurls look nice to. Like you I rarely if cut the diameter to match the knurl, I just plunge it until the knurl forms to a satisfactory shape. It may not be perfect but is just a aid to grip a part or tool.

If I am making something that I want to be real pretty I get more particular.

Kibby
02-26-2010, 09:23 AM
I've had to knurl 100's of these goshdarn knobs out of 6061 for my tappers. I made the mistake of selling a few tappers with these knurled knobs, and soon everyone would accept nothing less.

http://i485.photobucket.com/albums/rr220/pallymcgee/74197644_tapper-1.gif

Its was trial-by-fire for a while, and after a bucket full of screwed up knobs, and a half-dozen cheap chinese knurlers, I finallly made one that worked very well. I can tell you this - when I build some more I will get one of those Quick style of knurlers. The mess and the cleanup on these knobs was a horrorshow. In order to get a deep, well-defined knurl, you have to put some moderate pressure into it, enough to displace what amounts to a fair amount of metal... which then need to be trimmed off and cleaned up.

Toolguy
02-26-2010, 09:58 AM
Use Tapmagic for Aluminum on those knobs and it will go a lot better. It's the best for any aluminum working process. Milling, turning, parting, knurling, etc.

MuellerNick
02-26-2010, 10:01 AM
After knurling, I go over with a wire brush. Makes the difference!


Nick

Toolguy
02-26-2010, 10:12 AM
Agreed. Wire brushing or bead blasting really cleans up the looks of a knurled part.

Forrest Addy
02-26-2010, 11:10 AM
The REAL secret to knurling is getting the part's knurled diameter right. Treat the knurl roller like a gear cutter. Count the knurls in the roller and measure the roller diameter. Divide the knurl diameter by the number of knurl "teeth:" - this gives you a "pitch". Consider the diameter you're knurling. It generally has a loose tolerance. Adjust the knurled diameter slightly so the knurl roller's teeth track over a complete revolution.

3/4" knurl roller with 22 teeth = 3/4 / 22 = 0.0341 "pitch". Assume the dia to be knurled is 1 1/4". 1 1/4 / 0.0341" = 36.66. It doesn''t come out even and the knurl won't track correctly. It will "split the knurl. But the number IS close to 37. 37 * 0.0341 = 1.262". That 0.012" diameter change ensures the knurl teeth will track and the diameter increase will not violate most design tolerances. However if close fitted parts have to be slipped past the knurl you may have to adjust the diameter down to the next even tooth count.

MuellerNick
02-26-2010, 11:31 AM
The REAL secret to knurling is getting the part's knurled diameter right.

It's nothing more than an urban legend!
Just try to answer this question to see that all that math is useless:
What diameter is the right one? The one when you start knurling, or the one when you have knurled? Remember, that the effective*) radius is reduced by the pitch of the knurling wheel. So when the diameter is important when starting, why is it no longer important when you have finished knurling?

*)
The teeth first see the diameter of the part to knurl. Then, during knurling, they dig into work deeper and deeper and they see a different diameter of the work.


The wheels simply slip, that's why every diameter works.

This applies to knurling by forming. Things should be different when cutting. But I have no experience with it.


Nick

goose
02-26-2010, 12:06 PM
The REAL secret to knurling is getting the part's knurled diameter right. Treat the knurl roller like a gear cutter. Count the knurls in the roller and measure the roller diameter. Divide the knurl diameter by the number of knurl "teeth:" - this gives you a "pitch". Consider the diameter you're knurling. It generally has a loose tolerance. Adjust the knurled diameter slightly so the knurl roller's teeth track over a complete revolution.




In my, admittedly, limited experience, I find that diameter has nothing to do with it. Also, if so, the diameters for various pitches would have long since been determined, and would not texts like Machinery's Handbook have tables and so forth for proper knurl pitch/work-piece diameters?


Gary

cuslog
02-26-2010, 12:10 PM
My take on it;
In softer metals and non-critical diameters, I agree, you can mostly just "shove it in or squeeze harder" to "get er done", but what you're doing is effectively changing the working diameter of the wheels until they track completely around the circumference without crossing.
On harder metals where its not so easy to "smoosh" the metal around or critical diameters, I get the calculator out and adjust the dia.until its evenly divisible by the tooth pitch of the knurl.
It only takes a minute.
:rolleyes:

lazlo
02-26-2010, 12:22 PM
In softer metals and non-critical diameters, I agree, you can mostly just "shove it in or squeeze harder" to "get er done", but what you're doing is effectively changing the working diameter of the wheels until they track completely around the circumference without crossing.:

Yep, we've had that argument here countless times, and I agree -- you're ultimately measuring the circular pitch of the workpiece, whether you know it or not.

In the mash 'till it tracks approach, you either have a workpiece diameter that happens to be a multiple of the knurling wheel circumference and it tracks right off the bat, or you get overlapping knurls until you mash the knurling wheel in 'till it starts to track. Then you've plastically deformed the workpiece diameter to match the circular pitch.

That's the reason why there are diametrical pitch knurling wheels -- the circumference of the knurl matches standard stock sizes (1/4", 1/2", ...).

Carld
02-26-2010, 12:31 PM
Usually when I knurl something I just knurl it and FORCE the knurl to work. Sometimes the diameter is right for the pitch of the knurl and the knurl is easy to get.

I always wondered why that happened until I read a thread about that in which Forrest and others explained why the knurl is easy with a correct diameter. After some experimenting I found it true.

However, the fact is you can get a good knurl on any diameter if your willing to force the knurling tool to make it. I believe what is happening is the knurling wheels eat off the excess metal until it gets down to where the diamonds will come out. I believe this because I have watched the knurl go from a crappy looking mess and gradually start making a diamond.

I have started a knurl with the lines so close together it was crazy looking and after a while of forcing the knurler into the work it began to form a diamond and then finished out decent looking.

I too wire brush the knurl while it's in the lathe with a hand held brush. I use an air blast on the knurl as it is being formed to blow the chips away.

mf205i
02-26-2010, 02:26 PM
In my, admittedly, limited experience, I find that diameter has nothing to do with it. Also, if so, the diameters for various pitches would have long since been determined, and would not texts like Machinery's Handbook have tables and so forth for proper knurl pitch/work-piece diameters?


Gary
Machinery’s Handbook 27th edition, page 1240. Basically, an even multiple of 1/64 inch for 64 and 128 DP, and a multiple of 1/32 inch for 96 and 160 DP. I think that this is the reason that some foreign knurls give problems as they do not conform to the ANSI standard and therefore require experimenting to get the correct, probably metric, diameter.
Mike

MuellerNick
02-26-2010, 04:35 PM
I think that this is the reason that some foreign knurls give problems as they do not conform to the ANSI standard and therefore require experimenting to get the correct, probably metric, diameter.

Hahaha!
It's even worse! Metric knurls are not by diametral pitch, but distance between teeth. So you do get your pocket calculator and mulitply the diameter by Pi to get the circumfence ... NOT!

Look at www.zeus-tooling.de and show me where they even mention the circumfence (not for cutting!). They do almost nothing else than knurling.

And why wasn't my question re *what* diameter answered?
If you compare knurling to cutting teeth, you don't know how these are cut.



Nick

Ted Coffey
02-26-2010, 04:52 PM
If you start with the correct diameter your knurls wheels will last longer.
i.e., less wear.
Ted

MuellerNick
02-26-2010, 04:58 PM
If you start with the correct diameter your knurls wheels will last longer.

OMG!
If you start with the "right" diameter, you'll have a perfect mesh at the start, but a perfect mismatch at the finish. If you start with the "wrong" diameter, you'll have a match at the finish. No matter what, the knurl will have to slip.

You have to accept that the diameter of the work changes during knurling. If you don't, this discussion will never end.


Nick

lazlo
02-27-2010, 11:06 AM
Hahaha!
It's even worse! Metric knurls are not by diametral pitch, but distance between teeth. So you do get your pocket calculator and mulitply the diameter by Pi to get the circumfence ... NOT!

Zeus knurls are available in diametral pitch, circular pitch, and Teeth Per MM. Click the "Pitch P" tab and scroll through the selection:

http://www.zeus-tooling.de/produkte/raendelraeder_auswahl.php?formtyp=0&raendelformid=3&Submit=View+knurling+wheels

I have Zeus Knurling wheels for a Quick cut knurler that's listed as TPI (teeth per inch), but I'd be willing to bet they cross-list with a standard metric teeth per inch.

lynnl
02-27-2010, 11:42 AM
...

.... If you don't, this discussion will never end.


Nick

There's no "If" about it. This discussion will never end! :D :D

Let's talk about chickens and eggs. Anybody know which came first? :)

(I personally lean toward the chicken.)

Alistair Hosie
02-27-2010, 11:47 AM
Sorry to be so Unchristian but does it matter if it matches up so long as it looks ok and is knurly enough to roll between forefinger and thumb.It's not a piece of jewelerry:DAlistair my 4 cents Thats inflation for you

Alistair Hosie
02-27-2010, 11:48 AM
John why not sell us some precut knurled veneers and we can super glue them on?Alistair

saltmine
02-27-2010, 12:38 PM
Four cents? Alistair, how much is that in pence or pounds?

lazlo
02-27-2010, 12:41 PM
Let's talk about chickens and eggs. Anybody know which came first? :)

The endmill holder? :p

Carld
02-27-2010, 12:55 PM
We all can agree that with a standard rolled knurling wheel tool the knurl will be bigger than the diameter of the work. This won't apply to cut knurls.

When the knurl wheels roll the knurl the metal is lifted and formed into the diamonds so if the diameter to start with allows the diamonds for form easily that is good.

When the knurl is rolled onto a surface that is not a match for the pitch of the knurl it will take some extra force and removal of metal by the knurl wheels to form the diamonds.

The knurl may look a little better with the right diameter but you can still get a decent knurl if the diameter isn't right to start with.

You have to remember the standard knurling tool is a forming tool not a cutting tool.

John Stevenson
02-27-2010, 12:58 PM
John why not sell us some precut knurled veneers and we can super glue them on?Alistair

Not so daft Alistair,
I do a job about once a year for a guy who brings a six foot length of 2" stainless and I diamond knurl it the whole length, well less the one inch I need to hold on to.

No idea what it's for but I suspect he cuts slices off it as needed, I did ask but all he'd say was it was so simple he couldn't see why others weren't supplying the same part as him and wouldn't share what it was.

No problem, it takes about 20 minutes to do six foot on the big TOS so it's easy money.

.

John Stevenson
02-27-2010, 01:00 PM
We all can agree that with a standard rolled knurling wheel tool the knurl will be bigger than the diameter of the work. This won't apply to cut knurls.


It does apply to cut knurls as they cut and also displace, not as much as a form knurl but they are still larger than when you set out.

.

Carld
02-27-2010, 01:09 PM
Ok John, that works for me since my exposure to cut knurls is from what others have said.

Davidhcnc
02-27-2010, 09:37 PM
This is how I do knurls. This works every time regardless of diameters.

My knurling tool

http://homepage.ntlworld.com/david.hull35/CNC/knurl%20001.jpg

Touch on to the work like this and zero the dial.

http://homepage.ntlworld.com/david.hull35/CNC/knurl%20002.jpg

Start up and fed in until a good pattern is achieved.

http://homepage.ntlworld.com/david.hull35/CNC/knurl%20003.jpg

Read the dial. This is 1.8mm. Now we know where we are going. Notice the dodgy knurling on the dial!

http://homepage.ntlworld.com/david.hull35/CNC/knurl%20004.jpg

Davidhcnc
02-27-2010, 09:40 PM
Approach the knurling as screwcutting, lets say 5 passes to arrive at the final depth. First pass, withdraw and reposition for the next pass..you know the drill.
The knurls are registered each pass by the prestarted band.

After first pass

http://homepage.ntlworld.com/david.hull35/CNC/knurl%20006.jpg

Completed.

http://homepage.ntlworld.com/david.hull35/CNC/knurl%20008.jpg

Mystery steel 1" dia, speed maybe 300rpm and feed whatever you cut at, coolant, if you have the luxury or oil.

Carld
02-27-2010, 09:52 PM
Davidhcnc, that is an interesting method and since I have to knurl four parts this week I will try that and see how it works.

Do you use a carriage stop to keep from over traveling at the end of the knurl? I never have used a stop and sometimes it gets messy so I am going to try using my carriage stop this time.

Davidhcnc
02-27-2010, 10:04 PM
No carriage stop, Carl, but would usually 'trim' both ends of the knurl to sort them out....I don't know if you are at liberty to do so.


...let us know how you get on.

Carld
02-27-2010, 10:10 PM
Will let you know.

BadDog
02-28-2010, 02:05 AM
I've got a large (cheap) scissor knurling tool that works marginally well enough on large stuff. Well enough for my needs that I've not been motivated to buy, make, or fix it. However, it was USELESS on small stuff.

So I found a fantastic solution that I've mentioned before, but it doesn't seem to make much impact so far as I've seen. The answer is to look on ebay (or other) for old turret knurling tools. I've picked up several great name brand tools for near nothing (generally in the range of $15-$20 ex shipped!). Most even come with one or more sets of good name knurls, and in my experience most are still in good condition. Boyar Shultz is very common, though there are others. Below you'll see several of mine, and a tool post adapter that happened to come with one (though I cleaned it up a bit, mine are the nice looking cuts). Anyway, they are VERY rigid, smooth, and precise. You can even get some that allow you to control the angle and work somewhat like the "quick knurl" cutting tools.

Those that don't use the adapter (and other turret tools for that matter) mount in my boring bar holder if needed. For instance, using a "box tool" to function as a follow rest for small stuff.

Click for larger. Then you can click again on that image for full size if you want.
http://img4.pixa.us/626/14437267_th.jpg (http://baddog.pixa.us/images/14437267/)

MuellerNick
02-28-2010, 04:29 AM
This is how I do knurls. This works every time regardless of diameters.

That's almost how I do it. I can only say: Read post #14.

Only difference is, that I start to move left/right as soon as the pattern has cought up. But that doesn't make a difference. Sure you'll have retract the knurler a bit when the impressions are too deep to move sideways. But there's no need to remember the dial's reading. Just feed in, move left/right until the pyramid's tips are accute.


Nick

Circlip
02-28-2010, 07:05 AM
Yep, and if you follow that with post 16, we're talking 19 THOU steps on diameter, well within the CRUSH range of a knurdler.

Regards Ian.

SpyGuy
02-28-2010, 07:17 AM
What diameter is the right one? The one when you start knurling, or the one when you have knurled? Remember, that the effective*) radius is reduced by the pitch of the knurling wheel. So when the diameter is important when starting, why is it no longer important when you have finished knurling?
If you think about the knurling wheel and the workpiece as two meshed gears, it makes sense. I don't think you would argue that the pitch diameters of two meshed gears are unimportant.

MuellerNick
02-28-2010, 07:32 AM
I don't think you would argue that the pitch diameters of two meshed gears are unimportant.

Absolutely right. And again, the (pitch-)diameter changes during knurling. What ever way/formula you start with. It changes. Not constant.

So the calculated "right" diameter is only right for one moment.
Seems to be quite hard for some here to understand this. ;)


Nick

Ed P
02-28-2010, 09:05 AM
I saw a picture of a piece of tapered stock that a guy had knurled to debunk the "right diameter" theory. The knurling looked great from one end to the other.

Ed P

Carld
02-28-2010, 09:38 AM
Yep, knurlers are forming tools and they will "form" on any diameter.

John Stevenson
02-28-2010, 09:54 AM
You mean this one ?

Where a shaft was turned down in steps to random diameters.

http://www.stevenson-engineers.co.uk/files/stepknurl1.jpg

Then knurled.

http://www.stevenson-engineers.co.uk/files/stepknurl2.jpg


You can even see the original felt tip markings thru the knurl.

So what diameter is correct ???????????????????

{EDIT} you can see from the pics that this argument has been going on from at least 2004.

.

Tony Ennis
02-28-2010, 10:00 AM
John, is that success an attribute of the straight-line knurl, or does it apply to a typical diamond knurl also?

-=-=-=-

I don't mean to fan the flames (really!) but why is it some machinists' topics have people disagreeing so completely?

How can intelligent people produce knurls successfully using different methods then argue about how to successfully produce knurls?

Carld
02-28-2010, 10:00 AM
Could it have been argued from 1904? :confused: or earlier even yet.

Lew Hartswick
02-28-2010, 10:03 AM
You mean this one ?

Where a shaft was turned down in steps to random diameters.



Then knurled.




You can even see the original felt tip markings thru the knurl.

So what diameter is correct ???????????????????

{EDIT} you can see from the pics that this argument has been going on from at least 2004.

.
John did you mike the major D after the knurl? and did you increase
the "infeed" as it changed from step to step? (or "squeeze").
It would be nice to see one using a diamond knurl. I've done
some experimenting along these lines but gave up and for the
students just tell them to keep cranking the squeeze a bit till it tracks
this in on aluminium but it works on the projuets that haven't
been turned to the drawing diameter. :-)
...lew...

lazlo
02-28-2010, 10:06 AM
John did you mike the major D after the knurl? and did you increase the "infeed" as it changed from step to step? (or "squeeze").

Exactly. The amount of material displaced (squeezed), will change depending on how far off it is from the knurl's circular pitch.

John Stevenson
02-28-2010, 10:13 AM
No infeed changes, just engaged power feed and let rip.

I'll do a diamond knurl later, gotta pop out to get a new monitor for the CNC, only got 3 buttons showing and can't remember where the rest are :D

lazlo
02-28-2010, 10:17 AM
No infeed changes, just engaged power feed and let rip.

John, mike the knurls and see how much material was displaced on each step.

John Stevenson
02-28-2010, 10:26 AM
John, mike the knurls and see how much material was displaced on each step.

Can't on this one as I don't have the shaft any more, got turned down for something else or made into quick change toolpost stops ?

Will do the diamond knurl later, just won a 14" monitor on Ebay and got to go pick it up.
Can't get a bigger monitor in the enclosure.

Carld
03-01-2010, 01:04 PM
Davidhcnc, I did two knurls on a part for a tool I am making for profit. I tried your method and while I couldn't get the clean full pattern on the end you did it did help get a good clean final knurl. The second knurl I did was the normal way and I never did get it to be as good as with your method.

One problem is the metal was 1045 and that is a hard metal to knurl.

I think the next time I will angle the knurl tool a little to start the knurl and then straighten it out and finish it. I am going to consider buying a pincher type knurler or make the cutting knurler in the magazine article.

I am making more knurls than I want to here lately.

http://i82.photobucket.com/albums/j276/yeathatshim/P2280010.jpg

camdigger
03-01-2010, 01:14 PM
Or you could slap it in the drill press and use this doodad.
http://i766.photobucket.com/albums/xx301/camdigger/Shop%20made%20tools/PB291368-1.jpg
http://i766.photobucket.com/albums/xx301/camdigger/Shop%20made%20tools/PB291363-1.jpg

old blue
03-01-2010, 05:44 PM
A guy I work with had this to say about knurling.
Quote(Knurling can neither be learned nor taught you just have to do it.)

rgsparber
01-06-2012, 10:54 AM
In my, admittedly, limited experience, I find that diameter has nothing to do with it. Also, if so, the diameters for various pitches would have long since been determined, and would not texts like Machinery's Handbook have tables and so forth for proper knurl pitch/work-piece diameters?


Gary
I'm looking at MH 23rd edition, page 1112. It DOES specify the work blank diameter for various diametral pitches. For a knurl with a piametral pitch of 96, the work diameter should be a multiple of 1/32".

Tony
01-06-2012, 11:20 AM
Despite what anyone says the key to good knurling is low quality import knurlers.
Its important that the knurls have so much slop and play on their pins that
the knurls wheels and the workpiece "meet" at a happy compromise of diameters
for the pitches involved.

:)

or use good quality knurler and crank that cross slide until you hear the
motor start slowing.. thats when the nice patterns start to show.

Tony

lbhsbz
01-06-2012, 01:12 PM
I use the crappy knurler thing that comes with the import QC toolpost set.

Just don't lock the toolpost lever...it will center itself so that equal pressure is applied to both wheels. I'll rotate the toolpost a bit out of square with the workpiece to let the wheels bite better...concentrate all the pressure on less wheel area, it works nicely (most of the time)