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livessteammack
09-23-2010, 10:46 PM
I was wondering if anyone has built or is building the cut knurler by Michael Ward that has been in the last four issues of The Home Shop Machinists? I was recently in another fellows shop and decided to start building the pieces, as I sat there getting a list of material another fellow, who said he had been in the shop many years, stated that it would not work, you could not cut a very long knurl, and that it was not going to work do to its design. I quietly kept my mouth shut and was just going to see if anyone had built one. I still intend to build one since the cheapest that I could find on the internet was $600.

saltmine
09-23-2010, 11:05 PM
I've already built the prototype and have the final product almost finished.

Today, I started on the gear hob to cut the adjuster gear teeth.
I had a hob started but I made the mistake of starting it in a three jaw chuck, and ran into problems with concentricity. This time, I started the blank in a four jaw independent chuck (carefully adjusted to run concentric).
I got the shank turned, and cut all of the teeth. Now, I have to set up the hob in a rotab on my mill table and mill the cutting edges....then there's hardening and tempering....then I get to cut the gear blanks.

As far as it working...Well, aside from being a little tricky to set up without the geared adjustment feature, it performs perfectly, with two different size knurls, and it will cut a knurl as sharply defined and as long as you want.

Sorry guys, I'm not going back to my form (pressure) knurl, ever.

dp
09-23-2010, 11:26 PM
Maybe McGyver will check in - he's built one or two.

Mcgyver
09-24-2010, 12:23 AM
I've built one and i promise it will work. :D

How long does your friend need the knurl to be?

here's some early experimentation knurling 1/4" stock (iirc) - i always found a getting decent knurl on long slender pieces difficult. Its using the MkI version, simpler to build , a pita to use. same spindles but without the adjustments...you can get this result without all the adjustments, but its not a lot of fun (MkII happened because it was such a pita)...anyway, just included to show length of knurl shouldn't be an issue

saltmine, that is fantastic to hear... don't hesitate to get some pics up!

http://i785.photobucket.com/albums/yy132/michael01000/DSC_3078-large.jpg

http://i785.photobucket.com/albums/yy132/michael01000/DSC_3085-large.jpg

Bill Pace
09-24-2010, 12:51 AM
Well, I'm also building it -- or at least trying:o Along with thinking the concept of knurling in this manner would be too cool, it appeared to offer me the opportunity to do some machining processes that I had never tried -- and it has!!

One of the problems I have with having to wait between issues is that I get distracted with other projects, and that happened big time waiting on this last issue. So, I was torn between stopping the ongoing project and taking up the knurler again or ?? I finally gave in and started the gear making about a week ago, it didnt turn out so good! I made the "hobber" fairly easily - 1st one spun in collet, 2nd time the hardening process failed and 3rd time was a success. The gears were also a hit & miss and I made a few "prototypes" before I tried to assemble it.... missed it pretty badly. To some degree I was still distracted, and a lot more was inexperience, seems the biggest problem was - as saltmine said - concentricity.

I've set it aside for a few days to try and more finish up the other project - and, let the gear making stew in the old brain cells for a while.

This is the second project I've done from articles by Mcgyver, I like his manner of presenting his methods, and, the finished tool!

lazlo
09-24-2010, 12:55 AM
This is the second project I've done from articles by Mcgyver, I like his manner of presenting his methods, and, the finished tool!

What was the other? The finger brake?

By the way Michael, great job on the article!

Bill Pace
09-24-2010, 09:59 AM
What was the other? The finger brake?

Yes, I did the finger brake also....

Lew Hartswick
09-24-2010, 11:24 AM
I'm intrested in this "cut knurler" but am not about to get into making
gears. Is there any way to use available stock gears for this device?
I don't have the issues of HSM that have the article but could find
them I'm sure. ( suscribed for about 10 years but droped it a while back)
We use two scissor knurlers at school for the kids projects
so it would be interesting to see how much difference it would make
in the ease of success in the projects.
...lew...

saltmine
09-24-2010, 11:54 AM
A scissors knurl is a pressure/form tool which pushes the metal out of the way. This cut knurler actually cuts overlapping "V" grooves which become knurls. There's a whole lot less force involved with the cut knurl as opposed to the traditional knurl. I've actually put knurls on pieces of thin wall brass tubing with my MK1. You have to be real careful not to cut too deeply, though or you'll end up with brass wool.

Concentricity is easy to deal with by using an independent four-jaw chuck.
I was too lazy to use my four-jaw, at first, and soon discovered the problem. Even the best three-jaw scroll type chucks have concentricity problems, but they usually don't show up if you keep the part on the same axis...Flip the part over and you get problems.
With the independent chuck it only takes a few fiddly minutes to get the blank concentric (even though it does get frustrating if you get distracted or hurry)
Making gear hobs is one of those things where it's best to use as much accuracy as you have. And don't be afraid to scrap a less than perfect part. If you don't, it will come back and haunt you. (I spent a week staring at my first hob blank before I decided it wasn't worth trying to "fix"...Besides, I still had three feet of 3/4" O-1 drill rod left..That'll make a lot of gear hobs.

Your Old Dog
09-24-2010, 02:39 PM
I'm intrested in this "cut knurler" but am not about to get into making
gears. Is there any way to use available stock gears for this device?
I don't have the issues of HSM that have the article but could find
them I'm sure. ( suscribed for about 10 years but droped it a while back)
We use two scissor knurlers at school for the kids projects
so it would be interesting to see how much difference it would make
in the ease of success in the projects.
...lew...

Sounds to me like this might make a really nice group project where several members all build parts for each other. I am skilled enough that I can work to .01 tolerance :D

Lew Hartswick
09-24-2010, 08:53 PM
Sounds to me like this might make a really nice group project where several members all build parts for each other. I am skilled enough that I can work to .01 tolerance :D
Is that within the bounds of:
"Cut to size, file to fit, paint to hide" or is it part of the measure with
a yard stick, cut with a hacksaw, pound it in with a hammer. or some
equilavent? :-)
...lew...

lane
09-24-2010, 09:30 PM
Sounds to me like this might make a really nice group project where several members all build parts for each other. I am skilled enough that I can work to .01 tolerance
I know carpenters that can work that close.

Tony Ennis
09-24-2010, 09:32 PM
Is that within the bounds of:
"Cut to size, file to fit, paint to hide" or is it part of the measure with
a yard stick, cut with a hacksaw, pound it in with a hammer. or some
equilavent? :-)

Ouch, you guys are hitting awfully close to home!

oldtiffie
09-24-2010, 10:01 PM
Originally Posted by Your Old Dog
Sounds to me like this might make a really nice group project where several members all build parts for each other. I am skilled enough that I can work to .01 tolerance

Inches or mm?

0.01" = 0.254mm (say 1/4mm?)

0.01mm ~ 0.0004" (4 "tenths"?)

"Group projects" sounds too close to "Group Therapy" for my liking.

http://en.wikipedia.org/wiki/Group_therapy

I think I saw one fly over this cuckoo's nest.

http://en.wikipedia.org/wiki/One_Flew_Over_the_Cuckoo%27s_Nest_(novel)

How come all windows are barred, all of the doors are locked and all of the "Supervisors" are wearing white coats?

Is this "Group Therapy" "good for us"?

I've often wondered about why so many regard working in a shop as being therapeutic.

Maybe I need some more "group therapy".

Am I the only one?

livessteammack
09-25-2010, 12:18 AM
Well i'm no expert but theropy, it is simple. Do what you love. However whoever thought the shop is theroputic has not worked with the nut cases that hide tooling, move parts, and play horsey around the shop. Seems every shop I'm in o rvisit has these folks in it.

I am glad to hear the positive feedback on the cut knurler, it will be my biggest priority from hear on.