Buying involute gear cutters

[Swifty]

Is it just me ? but i get a lot of pleasure in producing something from nothing. I would not spend money on somthing that i can produce (and learn ). There have been articles on how to produce
invalute cutters, can dig them out if you like.

I feel the same way, although a lot of effort and it could still not work. I could have bought the gears quite cheaply, but decided to make them instead, so have put in some effort.

Paul.

 

[parisharma]

Great post I appropriate your post. I want to buy gear cutting tools. Can you please suggest me where I can get good quality of tools.

 

[Swifty]

The cutters arrived from CTC a couple of day ago, very happy with price and delivery time. The cutters look great, made an arbor to hold them and then cut one mitre gear. Before cutting, I re read Ivan Laws book a couple of times and used his 3 cut method. Before I go any further, I turned the blanks after researching on the Internet, and after finding the same sizes on a few sites, I was happy that I had the correct form. I cut the gears to the theoretical depth for the module, but when I checked the gear it looked as if the depth was too deep.

I'm still trying out different ideas, but not happy yet. One thing, I'm getting very good at turning the blanks. Anyone with any ideas would be appreciated.

Paul.

 

[radial1951]

... making the hobbling cutter and cutting some spur gears. When I have the mitre gears ready to cut I will take more pictures and post about it.

By the way, mitre gears work in sets of 1:1 ratio, bevel gears work in different ratios...

Paul.

Hi Paul, with all respect, the typo error "hobbling" needs to be corrected. A newbie to the art of gear cutting may not realise that "hobbing" is the term used for one of several methods of generating a gear tooth profile, based on the theoretical rack of the same tooth size/shape, and the cutter is called a "hob".

No offence intended, but also .... By definition, any pair of gears connecting two shafts, whose axes intersect, are BEVEL GEARS. A pair of IDENTICAL BEVEL GEARS, with 45 degree pitch cone angles, are known as MITRE GEARS i.e. 1:1 ratio and shafts at 90 degrees.

As I'm sure you know, the correct tooth profile for Bevel Gears cannot be produced with a milling cutter.

BTW, parallel depth bevel gears do look a bit strange, maybe because the Module size of the cutter suits the small end of the teeth. As a rough guide, for Module 1, the pitch line is 1mm down from the top of the tooth, and the tooth thickness at the small end, on the pitch line, is about 1.57mm. Guesstimating with a vernier caliper will give you an idea if you are within cooee (that'll throw 'em).

This link was on HSM: http://www.archive.org/stream/americanmachini00logugoog#page/n148/mode/1up - Good info, see page 144.

Regards, RossG.
radial1951
______________

 

[rcaffin]

I've bought a fair bit from CTC, direct.
The runout on the ER25 collets was less than the runout on the mill.
Some carbide cutters are specified for wood, plastics and Al. Fair enough, don't use them on steel.
Some of the cutters specified for steel are truly wicked!

Cheers

 

[Swifty]

Hi Paul, with all respect, the typo error "hobbling" needs to be corrected. A newbie to the art of gear cutting may not realise that "hobbing" is the term used for one of several methods of generating a gear tooth profile, based on the theoretical rack of the same tooth size/shape, and the cutter is called a "hob".

Have corrected the spelling error, my fat fingers on the iPad caused the extra letter. Will check out the web site.

Paul.

 

[Swifty]

BTW, parallel depth bevel gears do look a bit strange, maybe because the Module size of the cutter suits the small end of the teeth. As a rough guide, for Module 1, the pitch line is 1mm down from the top of the tooth, and the tooth thickness at the small end, on the pitch line, is about 1.57mm. Guesstimating with a vernier caliper will give you an idea if you are within cooee (that'll throw 'em).

According to Ivan Laws book, the cutter number chosen should reflect the large end of the gear. Which, in my case, when trying to cut 20 teeth the cutter chosen should be for 28 teeth. Therefor I should use cutter no:4 instead of cutter no:3. The tooth thickness at the small end is a lot smaller than what you state. It would be better if I could make a cutter to cut the "tooth" instead of the "gap", but not practical. Back to the drawing board for me, and more studying.

Paul.

 

[gus]

I've bought a fair bit from CTC, direct.
The runout on the ER25 collets was less than the runout on the mill.
Some carbide cutters are specified for wood, plastics and Al. Fair enough, don't use them on steel.
Some of the cutters specified for steel are truly wicked!

Cheers

Hi RCaffin,

Two sets of Gear Cutters came in from CTC week ago.
Inspected one set that I will using shortly from now to cut Module 0.8 pinion.
Some cutters are very well ID marked with Cutter nos. No of teeth etc,
Some have very faint marking that I cannot read.Emailed CTC and so far no resonse.

CTC end mills are usable.

It is true even Littlemachineshop have quality problems.Been buying from LMS and had one Precision Tool Maker Vice I am not happy.But they gave me refund.I am still buying from LMS.


Gus Teng from faraway Singapore.

 

[rcaffin]

Some have very faint marking that I cannot read.Emailed CTC and so far no resonse.

Can take them a few days to reply sometimes. But I have found them fairly reliable.
I have had faint markings on collets, but I found that if I angled them 'just right' to the sun they were quite readable. No, I don't know what is 'just right' - sorry!

Cheers

 

[rodw]

Hi RCaffin,

Two sets of Gear Cutters came in from CTC week ago.
Inspected one set that I will using shortly from now to cut Module 0.8 pinion.
Some cutters are very well ID marked with Cutter nos. No of teeth etc,
Some have very faint marking that I cannot read.Emailed CTC and so far no resonse.

Gus Teng from faraway Singapore.

Gus, can you work them out from the detailed specifications on CTC's web site?
Try http://www.ctctools.biz/servlet/the-629/hss-involute-gear-cutter/Detail

It took me a while to realise in their listings there is another tab with more info. Click on the "Detailed Description" tab to see it.
I am not really ready to tackle any gear cutting yet so in this case it does not make much sense to me..

 

[Swifty]

The set of cutters that I purchased fron CTC also have hard to read markings. But one positive thing was that the greasy paper that the individual cutters were wrapped in had the cutter number written on it in marker pen. Will get around to engraving the cutters with correct details one day.

Despite that, they are very good cutters.

Paul.

 

[aarggh]

All the involute cutters I've bought off CTC have been very good quality, and very cheap! The markings on my sets are quite fine to read.

cheers, Ian

 

[gus]

The set of cutters that I purchased fron CTC also have hard to read markings. But one positive thing was that the greasy paper that the individual cutters were wrapped in had the cutter number written on it in marker pen. Will get around to engraving the cutters with correct details one day.

Despite that, they are very good cutters.

Paul.

Hi Paul,
I agree with you. The grease paper is ID marked. Will be cutting a Module 0.8 Pinion gear for the Webster Engine Timing Train in two weeks time.

Your expertise is seeked.The wrapping will sooner or later go bad.How do I etch or engrave on hard steel.

Gus Teng.

 

[gmac]

Gus;
Try a chemical etching pen, similar to this;

http://www.etching-pen.com/index.php?id=11&L=13
http://www.flexbar.com/shop/pc/METAL-ETCHING-PEN-p3113.htm

There must be something similar in your neck of the woods.

Cheers Garry

 

[Swifty]

Hi Paul,
How do I etch or engrave on hard steel.

Gus Teng.

Hi Gus, I was intending to engrave the cutters with a diamond coated bit or a fine pointed mounted point in my dremel.

Paul.

 

[gus]

Just came up with a way to mark the gear cuttter no 4. Number stamp the arbor. Looks like I have to all 8 arbors and stamp all arbors. Will make a small wooden box to house and display
Module 0.8 Gear Cutters.Will be another thread.

Meanwhile I am very happy with my private gear cutting lessons.
Instructor-----------Gus Teng. Student-----------Gus.
Cut a good gear after three practice cuts. See fotos.
Ten days to make Dividing Head and Tail Stock Centre. And only half day to come up with a
good looking mini Spure Gear. Harold Hall's design was good and strong.

 

[Philjoe5]

Gus,
I'm watching the gear cutting and appreciate your posting. I'd like to buy the CTC set of cutters but I contacted them about getting the proper arbor to hold the cutters and they don't supply them. Where did you find the abors to go with these cutters?

Cheers,
Phil

 

[rcaffin]

I'd like to buy the CTC set of cutters but I contacted them about getting the proper arbor to hold the cutters and they don't supply them. Where did you find the abors to go with these cutters?

Bit of silver steel (aka 'drill rod'). I make them up regularly for mounting diamond wheels and CBN wheels.
Actually, heat treating them afterwards is probably optional. I have not done all of mine.

Cheers

 

[Swifty]

Same as rcaffin in the above post, just make your own. I use mild steel mainly, or whatever odd bit of steel that is lying around. Seems that Gus is making a holder for each cutter, just make the one and change cutters as required.

Paul.

 

[Philjoe5]

Paul, Rcaffin,
Thanks for the tip. The metric thread drawbars on arbors for this set of cutters, won't mix with the Unified threads on my machine. It seems like the best way to go...make 'em myself.

Cheers,
Phil