[keen]

Greetings.
I have invented and developed a new type of internal and external portable screw thread cutting machine. I am doing some research to see what its market potential is. I attach some jpg's and a Youtube link:

[nomedia="http://www.youtube.com/watch?v=pJRCN9G-jBk"]YouTube- Thread cutting machine[/nomedia]

Let me know if you are interested.

[maltria]

Looks simple, cheap and effective all the ingredients to make it successful.....

How about adaprting it to take off the shelf thread milling cutters ?

[crazyau]

Looks great! How does it go with stainless and other "fun" material?
As for your best option - I guess it depends how much work/ money you want to put into it!!

Good luck

[chich2]

Nice machine! With another automated axis it could do tapered pipe threads too.

Great to see someone having a go.
Hope it works out well for your new invention.

Chich

[maltria]

Could simply rotate the headstock around the vertical axis .... like offsetting the tailstock

[rowbare]

I like it. It is a nice adaptation of thread milling.

bob

[keen]

Thanks guys. I need lots of feedback before I can be sure of the best road forward.

Here is more info - and it should answer your stainless question . I paste below a blurb I have prepared.

Machining of Screw Threads
In order to put Threadexpress in its context I present a little background. It has struck me for many years that screw thread cutting is a relatively poorly developed process that poses many problems for service engineering companys, mechanics, machinists and DI Y ers etc compared with other machining/engineering processes. Ask a machinist to read the following and he will certainly concur:

Taps,dies, chasers etc are convenient but only give average results and large diameters and tough materials test their inherent limitations. Of course an additional problem is the almost limitless range of tooling needed for all the thread pitches and diameters.

Manual Lathe screwcutting Gets around the need for these tools, but presents its own limitations. A lathe needs a large range changeable ratio gearbox to supply the many different required ratios between the lathe spindle and leadscrew . This makes it complex,heavy and expensive (or it has a limited range). Screw cutting on a lathe requires advanced training and good aptitude to overcome the inherent limitations of this machining process. If one sets the speeds and feeds at optimum, the tool is in contact with the chuck before you can blink.
If one sets them at safe settings, repeat cuts tear and highly load the tool and work, and a tidy run out each time is difficult. The run-out area puts loads on the tool tip that are erratic and mean new generation carbides etc are likely to chip.

CNC mills and lathes Overcome a lot of the above issues however the average mechanic,machinist or DIY usually cannot afford the capital cost or steep and long learning curve of CAM/CNC.

Threadmilling It just so happened that my background as toolmaker/machinist caused me to repeatedly run up against the above problems. I needed to produce accurate threads with a neat run out for Plastic Injection Mold unscrewing cores, and later on again needed to machine tough stainless steel special fasteners for highly stressed high pressure pumps. This caused me to study and develop thread milling, in the form of thread milling attachments for my lathes. It soon became clear to me that this machining process overcame many of the inherent difficulties above. The cutter could be carbide and run at high speeds, the work could be turned slowly – even by hand, and one or two cuts only were needed. The best part was the run outs were safe and clean and the finish high.
There were obviously sound principles at play here.

Threadexpress While doing this work it was clear to me that the machining loads were remarkably light. I began to think that the potential of this already established process was not being fully capitalized on. If the cutting loads were so light that the the chuck could safely be turned by hand – and the work and cutter spindle could be so slender and yet not generate much chatter, why couldn't a light and simple, even portable, new type of machine tool be produced.......
Of course the reason was that a complex and expensive gearbox would be needed for all the different pitches.....So there it sat for several years.

One day a mechanic friend wanted some special studs screw cut for his rally car urgently. And yet again it struck me. This is crazy, why does it so often have to be such an issue for all of us hands on people, to get good threads cut ? That day I came up with a radical idea.

A light and simple pitch generating new technology that allows a limitless range of pitches and diameters to be quickly set and cut. I did the calcs and research, It seemed too simple and too bizarre to work. I developed the design more fully and slowly began to believe it just might work. I then began to search invention data bases for any other inventor that might have invented it also - (but who had obviously failed to capitalize on it). Over*many hours*over many days I viewed*scores of inventions, all far more complex or difficult to manufacture, and found nothing the same.

I then began the construction of the prototype.*I decided this prototype should not just test the unusual operating principle, but also test how it would work in practice as a lightweight or even portable machine tool.*I spent many hours refining the design and building a 'semi production' prototype. I cut unimportant corners where we could, but put the time into refining the design and construction of the key areas.

The operating principle worked so well, that even in its preliminary thrown together stage, it was very promising. I further refined the machine and tried it on a tough high tensile steel M12 bolt. I*know from many years of hands on design, toolmaking and machining experience the difference between a marginally functioning design, and a machine that just 'wants to work' This is one of those. See actual part JPEG at the start of my thread. Try doing that with a dienut or on a lathe – let alone a light weight portable machine!

Thanks for wading through all that!

[keen]

Hi maltria
Re: How about adaprting it to take off the shelf thread milling cutters ?[/QUOTE]

Yes, the current cutter setup is just for the prototype. It would probably suit a budget DIYer.

A collet type cutter holder would allow using off the shelf thread milling cutters and have some advantages.

[keen]

Hi again maltria

Re taper threads:

Could simply rotate the headstock around the vertical axis .... like offsetting the tailstock [/QUOTE]

Thats what I have been thinking also, It would add a little to the cost.
Feedback on desire for this feature appreciated!

[307startup]

I like it

[jatt]

RE: the questions at the end of the vid.

How much work do you want to do?

If you can find someone to buy the idea outright or pay royalties then that is obviously the easiest for yourself. If it was me in this instance would try for having it purchasing it outright, before the likes of the Chinese got onto it and started churning them out. Seems to me they have no regard for US style patent laws.

Selling the plans: not a bad idea. Plenty of others out there doing that with their respective gadgets. Making some parts yourself for sale upon request.


Idea looks to be a goer. Good luck with it.

[keen]

[QUOTE=jatt;768568]RE: the questions at the end of the vid.

How much work do you want to do?"

Hi Jatt - I suppose I need feedback/ market information before I decide which option forward is best. I dont mind work, as long as it is productive. What option do you guys prefer?

If its buying the plans - would you buy them? How much do you think would be a fair price? .... etc... etc

[juergenwt]

Keen- Nice machine and looks like a great idea.
Now the hard question:" Where would you use it and who would you sell too"?
In other words: Where is the market?
Large manufacturers of screw and threaded product - not competitive.
Home style shops - not enough usage.
That leaves you with medium size specialty shops having small production runs.
Your competition in those shops are for most applications the simple low cost dies.
I could see a possible market in the US where many medium size shops have a number of old US made lathes not capable of cutting metric thread and need a cheap way to produce metric threads. Many of these shops are hanging on to the old machines and find themselves loosing business because they don't want to spend money on metric capable equipment. Worth a try. Good luck.

[keen]

QUOTE=juergenwt;768867]Keen- Nice machine and looks like a great idea.
Now the hard question:" Where would you use it and who would you sell too"?
In other words: Where is the market?
Large manufacturers of screw and threaded product - not competitive.
Home style shops - not enough usage.
That leaves you with medium size specialty shops having small production runs.
Your competition in those shops are for most applications the simple low cost dies.
I could see a possible market in the US where many medium size shops have a number of old US made lathes not capable of cutting metric thread and need a cheap way to produce metric threads. Many of these shops are hanging on to the old machines and find themselves loosing business because they don't want to spend money on metric capable equipment. Worth a try. Good luck.[/QUOTE

Thanks juergenwt. Good idea. Perhaps a cnc zone member is following this (from a medium shop as above) - needing metric screw cutting ... any thoughts......

What do you think of these possible applications...

Portable applications....."where your team is headed you know repair shops will be few and far between. perhaps you are mechanical support for a racing team - Or you manage a remote military post and your mechanic asks you - where is the nearest machine shop. Your marine vessel workshop did not qualify for a lathe installation and you are heading for the end of the earth, You are in trouble, you need a replacement screw or bolt now. The industrial supplier is closed or miles away. You need to reassemble your vehicle/machine this evening, not on Monday or when the courier eventually arrives. You don't have access to a lathe or your lathe won't cut that pitch thread. You could consider using a die if you had the right one! But then cutting a high tensile bolt with a split die or die nut is decidedly borderline. Even an expensive HSS die will not last last long.

No problem with Threadexpress. Find a suitable stock bolt or rod and cut the thread you want...... .

Also shallow blind threads and threads without a run out undercut groove are a real challenge to machine. Again, here threadexpress comes into its own. Internal thread cutting is much easier than other traditional thread cutting methods.

Many thanks for your feedback so far - please keep it coming!

[machinechick]

That's a really neat concept! Wonder how long it will take the Central Machinery version to get to Harbor Freight! Not only do the Chinese not respect copyrights, the Americans haven't enforced the law for about 20 years against any ChiCom "company" (they basically suppport the US so we can't mess with "daddy").
Be great if you sold it as a kit like a Quorn (maybe just a print download), at least you'd make some money off of your idea. With the additional benifit of not having to put much money up front.
Good idea to really saturate all the sites that this is YOUR idea and YOUR invention so at least everyone that buys the version the ChiCom will steal know they are a deluxe(chair) heel!

[daman]

Are there thread milling bits so you can do this on a CNC mill?
I thought this kind of thread machining was normal just like using taps.

[mactec54]

Hi keen

I to do mold making & was doing this type of threading in NZ many years ago, we were using a rotary mounted cutter in a lathe for cutting threads for our mold cores, We would also grind them the same way as well, if we had to after heat treatment

I first saw this being done by a German mold maker in NZ near Wellington in the 1970s & was a very simple set up for doing mold threaded cores, & we have done it ever since.

I'm sure a lot of other moldmakers use this process to cut there threads still today even with CNC lathes with live tooling, this is still the most cost effective way to do it to get perfect threads

So nothing new in your process, Just put into a portable machine form

Your drive for your cutter needs to be mounted a lot more ridge than you have it, you need to have a housing with bearings in, that can support the cutter load without any chatter while it is cutting the thread, you then can drive it with the same simple tool that you are using

For the US you will need it to be able to do all Inch thread forms as well as the Metric

I know this is your proto type, So keep up the good work, & you will make it even better

[rowbare]

keen,

I take it from your description that you are using a mechanical means to synchronize the spindle rotation with the cutter movement?

bob

[keen]

That's a really neat concept! Wonder how long it will take the Central Machinery version to get to Harbor Freight! Not only do the Chinese not respect copyrights, the Americans haven't enforced the law for about 20 years against any ChiCom "company" (they basically suppport the US so we can't mess with "daddy").
Be great if you sold it as a kit like a Quorn (maybe just a print download), at least you'd make some money off of your idea. With the additional benifit of not having to put much money up front.
Good idea to really saturate all the sites that this is YOUR idea and YOUR invention so at least everyone that buys the version the ChiCom will steal know they are a deluxe(chair) heel!

Thanks machinechick. You reinforce my thoughts. appreciated.

[keen]

Hi keen

I to do mold making & was doing this type of threading in NZ many years ago, we were using a rotary mounted cutter in a lathe for cutting threads for our mold cores, We would also grind them the same way as well, if we had to after heat treatment

I first saw this being done by a German mold maker in NZ near Wellington in the 1970s & was a very simple set up for doing mold threaded cores, & we have done it ever since.

I'm sure a lot of other moldmakers use this process to cut there threads still today even with CNC lathes with live tooling, this is still the most cost effective way to do it to get perfect threads

So nothing new in your process, Just put into a portable machine form

Your drive for your cutter needs to be mounted a lot more ridge than you have it, you need to have a housing with bearings in, that can support the cutter load without any chatter while it is cutting the thread, you then can drive it with the same simple tool that you are using

For the US you will need it to be able to do all Inch thread forms as well as the Metric

I know this is your proto type, So keep up the good work, & you will make it even better

Hi mactec54. Thanks for your thoughts.

One key thing that is unique about this machine is the pitch generating technology. Any pitch thread within its range can be cut, inch or metric - without the need for a heavy and expensive gearbox, or any master pitch formers. This is new - I have searched inventions for many hours.

Sure thread milling is an established process - I also used to use a more heavy duty attachment with heavy bearings spaced further apart to cut my precision mold cores etc. I at first tried this attachment on 'threadexpress'

But I decided to try a modified $20 angle grinder also because I wanted to see how light, portable and cheap this machine could be. I found that with a carbide fly cutter, I could use much higher rpm and the cutting loads were much lighter - I was surprised by how well it cut and how little ridgidity is actually needed with higher rpm.