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The ettiquette of sharing designs

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Calum Galleitch01/04/2022 23:44:37
194 forum posts
65 photos

This is not a question about the law of copyright, which I understand reasonably well. It's more about what the norms/expectations are in the world of home machining.

Specifically, I've been drawing up a few different bits and pieces in OnShape recently (a Fusion360 equivalent), and I'd like to share some of them both for feedback and in case anyone should find them useful. Specifically, they are:

  • A float-lock vice (a light drilling vice)
  • Harold Hall's QCTP
  • My own version of the MLA-23 toolpost.

The float-lock vice I have drawn up from pictures and videos. I don't think they are made commercially and the designer has long since departed. I am fairly sure no form of legal protection exists and I would have no qualms about sharing this.

Harold Hall's QCTP is his own design, is copyrighted, and even though his design is free to download from his website I don't feel it would be right to publicly share my version without knowing his views. That said, I wouldn't feel inhibited from sharing the design with a friend or someone I was seeking advice from.

The MLA-23 inspired toolpost - although it shares the same look and operating principle as the original - is drawn from scratch, and nothing has been copied dimensionally; I have also changed the locking mechanism slightly. This is the item I feel less sure about sharing; while I don't think I would be breaching copyright, it's very clearly not my design and the designer is still selling the design commercially. On the other hand, it's a simple design and any competent machinist could knock one up from a photograph.

A lot of my thinking here is coloured by my experience of the accepted standards in my corner of the musical universe. It's normal and unquestionable for teachers to supply music to their students without seeking permissions; likewise between friends and within bands. There is however a strong culture of "buy the book" and supporting the people who put music out there. At the same time, there's a recognition that it's a bit daft to have strictures about sharing sheet music when you can simply listen to someone playing it and write that same bit of music down for yourself.

Thor 🇳🇴02/04/2022 08:49:52
1660 forum posts
46 photos

Hi Calum,

I would agree with you about publishing your drawing of the float-lock vice, I assume you will give credit to those who desrve it. Regarding Harold hall's QCTP; I would say; of course you ask his opinion. I agree that the MLA-23 inspired toolpost is more difficult, but publish it and see what happens.


Michael Gilligan02/04/2022 09:06:34
20289 forum posts
1064 photos

Re. the MLA-23

On the generally good principle of “credit where credit’s due” … why not contact the designer, and offer him your work to illustrate his website ?


That way; he gets a few more $6 purchases, and you get ‘exposure’

… I think that’s what they call ‘Win-Win”


Clive Foster02/04/2022 09:24:47
3173 forum posts
113 photos

I see no issues with sharing the toolpost designs if you have changed them.

Obviously if its a simple build thread then reference back to the source rather than publish your drawings.

If its an "I liked the idea but changed things because I thought that would work better / be easier to make / better fit with my machine" or whatever then frankly the changes, unless stupidly trivial, make it your work so free publication is fine. But reference the source because other folk may prefer the original.

Copying and modification is how progress gets made after all.

Commercial use is a little different because clearly the person who has gone to all the trouble of developing something that works is entitled to a fair return on that effort. Patents are explicitly published so folk can copy and improve but "should" give the innovator protection form other folk selling something containing that innovation for several years after.



john halfpenny02/04/2022 09:33:03
253 forum posts
24 photos

Broadly speaking, if you take inspiration from one or more third party designs, and draw/dimension your design without direct reference to those other designs (eg on a clean sheet of paper in an empty room with no reference matter), you will have a defence to an action for copyright infringement because you did not copy. On the other hand, taking a third party design, and changing it so that it no longer resembles the original, is prima facie copyright infringement because copying was part of your design process.

This is necessarily a brief (UK) guide to a very complex legal construct, which varies considerably from country to country, and, as they say, each case turns on its merits (and lawyers can be very inventive and occasionally aggressive). Seeking permission is always a good idea, but not always practicable - it is your desire to publish which is the practical issue here.

Dave S02/04/2022 10:31:13
374 forum posts
90 photos

Im not a lawyer and have never played one on tv... disclaimer out of the way....

I don't think what John says is correct.

The process by which a thing is designed does not matter in copyright infringement. What matters is if the thing is a copy. So John's illustration is backwards imo.

As for the original question first one:

You have designed a vice. This is most likely not a "copy". There are features of a vice which are required for it to function. These features cannot be subject to copyright claim, hence most vices look quite similar. If a vice has a design feature that is aesthetic then copying that would be infringement.

Second one: You have made a CAD model of an existing published design. You are not trying to pass off as your own design, so I don't thinks there would be any issues - the whole design was published into the public domain with the clear intention that people would use it. Give credit and ask Harold if he has objections if you want (I would just because it's polite to do so) but if you wish to publish a CAD model of a design the 'thing' you are publishing is your work, based on Harolds work. So again I don't believe that there is any infringement.

Third one: Is much like the first. You have taken an idea and used it for your own design. It doesn't sound like a "copy" but an improvement. Features like removable tool holders are required for the design to function ago are not subject to copyright protection (patent protection is a different matter.... But I don't see a patent on the design)

Intellectual property is a wide area, but basically my understanding is copyright protects the "look" of a thing and patents protect how a thing works (in the UK anyway)


Alan Jackson02/04/2022 10:32:36
260 forum posts
146 photos

Hi Calum,

A while ago I made my version of the MLA toolpost and this is the reply I got from the MLA membership. So as long as you credit the originators I do not see any problem with copyright.



compliments on your nice looking version of the MLA toolpost. Also, the topslide compound it's mounted on is sheer elegance.

I would just like to bring up one thing, that with the original, prototype version of the toolpost it was found that the dovetail clearances in the relaxed position should be around four or five thou., ideally, if I remember correctly, and not to exceed about seven thou. Those tolerances were easily accomplished by gauging with the toolpost body when milling the toolholder dovetails. I now have seventeen toolholders of various types, and presently there is no urgency to make more. When there is, should there be access to a milling machine, I would consider pre-milling the dovetail in a long slab of steel and, as needed, sawing off from it toolholder blanks like slices from a loaf of bread. The key would be in milling the dovetail with reasonable accuracy, so that the toolholder blanks would all fit equally well, rather than equally poorly.

A friend and I, using his milling machine, made a pair of larger versions of the original, prototype toolpost, with the intent that one of them would be used on his South Bend heavy ten lathe, using the large collection of Aloris and knock-off Aloris toolholders he already had, as well as some he had made.

During that project we decided to measure the dimensional variation, or "allowance" among them, and found the variation to be too great to be accommodated by the MLA toolpost without alteration. I forget what the variation was--I think I could look it up--but it was quite significant. Which does point to one advantage of the wedge type toolpost, in that it is fairly tolerant of dovetail dimensions. That can be seen, if I recall from my friend's lathe, in the various positions the Aloris locking handle assumes depending on the toolholder mounted.

That is certainly not to discourage the choice of the MLA toolpost in favor of the wedge and plunger types. The MLA is more easily made by the amateur machinist than the others, and in my opinion is more rigid, having full dovetail engagement with no interposed pieces. I mention it to point out that the cheap knock-off toolholders might not be suitable for the MLA toolpost, as suggested in a comment a while back.

JACKARY, it might be interesting finding out if you have measured the dimensional variations, or "allowances," among the dovetails of the toolholders you've made so far. Though I have to say, just from a feeling I get looking at the photo of your toolpost, that yours appears more flexible, and capable of greater expansion, than the prototype, and so more capable of accommodating greater variations in the toolholders. Again, compliments on a nice looking job.

New Topslide.jpg

Edited By Alan Jackson on 02/04/2022 10:34:14

Edited By Alan Jackson on 02/04/2022 10:36:00

Edited By Alan Jackson on 02/04/2022 10:37:21

David-Clark 102/04/2022 10:55:00
222 forum posts

Normally a patent/ copyright on a design is valid for 15 years. Then you should be free to pass it around.

John Haine02/04/2022 11:11:10
4718 forum posts
273 photos

Patents last 20 years from filing (assuming it is granted).

Copyright is variable depending on the work. This from the Government website (shamelessly copied):

Type of work How long copyright usually lasts
Written, dramatic, musical and artistic work 70 years after the author’s death
Sound and music recording 70 years from when it’s first published
Films 70 years after the death of the director, screenplay author and composer
Broadcasts 50 years from when it’s first broadcast
Layout of published editions of written, dramatic or musical works 25 years from when it’s first published

The length of copyright also depends on how long ago the work was created.

SillyOldDuffer02/04/2022 12:02:25
8897 forum posts
1998 photos
Posted by Calum Galleitch on 01/04/2022 23:44:37:

This is not a question about the law of copyright, which I understand reasonably well. It's more about what the norms/expectations are in the world of home machining.

to share some of them both for feedback and in case anyone should find them useful. Specifically, they are:

  • A float-lock vice (a light drilling vice)
  • Harold Hall's QCTP
  • My own version of the MLA-23 toolpost.
A lot of my thinking here is coloured by my experience of the accepted standards in my corner of the musical universe. It's normal and unquestionable for teachers to supply music to their students without seeking permissions; likewise between friends and within bands. There is however a strong culture of "buy the book" and supporting the people who put music out there. At the same time, there's a recognition that it's a bit daft to have strictures about sharing sheet music when you can simply listen to someone playing it and write that same bit of music down for yourself.

I suggest this very much is a question about copyright (and patents)! Model Engineers aren't exceptions to the law just because they're hobbyists.

I think the best way to stay safe is to understand the money aspect. If someone else's income is effected by an infringement of their rights, or their income could be effected in future, they will probably come after you. How violent the reaction, if any, depends mostly on the amount of money involved.

If a hobbyist privately shares a few copies of Harold Hall's design amongst his mates, I doubt HH will know or mind. But if Callum publishes his version of HH's design on the internet, open to everyone in the world including foreign manufacturers, then HH might well be concerned about losing book sales or the commercial rights to his design via Callum's version of it. In this case, I think HH should be asked for permission. It's HH's right to decide if Callum's efforts are good because they promote the book, or not!

The Float Lock vice is safe provided the patent has expired.

Callum's version of the MLA-23 tool-post needs formal permission as well. Recent design, sold as a kit, and the plans are still available for $6 each from the copyright owner.

Whether the US seller would chase an individual in the UK infringing his rights to a $6 drawing I have no idea. Legal action is expensive, so it probably won't happen unless serious money is involved. Could be - for all we know Seig and Colchester are in a bidding war for the rights to mass produce the design. Safest to get permission from the US.

It's wrong to believe making small modifications and improvements to a design are enough to evade copyright and patent protections. You only own the rights to the changes, not to the original design. Many examples of firms being obliged to pay big money after their in-house design was found to infringe someone else's existing rights, accidentally or deliberately.

Callum says 'A lot of my thinking here is coloured by my experience of the accepted standards in my corner of the musical universe.' And the corner he describes is typical of the low-value sharing that goes on in amateur circles. Copyright owners would like their money but it's too difficult to collect from a multitude of informal small groups!

Other parts of the musical universe aren't so cosy. The music industry pursues businesses aggressively: Performing Rights Society Inspectors march into a Hairdressers and are owed money if the customers are listening to pop music on a free-to-air radio. A business has to have a licence. And Mr Ed Sheeran is in court at the moment, because his song 'Shape of You', allegedly infringes Mr Sam Chokri's 2015 single 'oh why'.

The difference between Callum and Ed Sheeran is one of them is a big earner.

I suspect Copyright and Patent Law rarely impact Model Engineers because much of what we do goes back at least 50 years. Our designs are mostly variations of protection-expired ideas, many of them Victorian. Few of us design new world beating machine tools, solar panels, room temperature superconductors, smart phones, electric cars or fusion reactors!


john halfpenny02/04/2022 12:02:41
253 forum posts
24 photos

Calum will not get a definitive answer to his complex issues on this or any other forum, so he needs practical advice, given the complexity of copyright law, especially as it relates to engineering drawings. This has a long legal history in the UK. Bear in mind that you cannot prevent an aggrieved person commencing legal action. So you must mitigate the risk by not copying features, or combinations of features which might be proprietary. Of course, 'old' features may be free to use if the relevant copyright has expired. This may of course require research. Generally speaking, the more effort taken to avoid third party copyright, the better the potential defence if a claim arises. Permission and/or attribution can further reduce risk.

In practice a copyright claim is rather difficult to prosecute, since the onus of proof rests initially on the copyright owner (unlike patents, which btw expire before full term if annual renewal fees are not paid). That is why reported copyright cases are lengthy and often ruinously expensive. Perhaps Calum's risk is low (maybe he is not worth suing), but he will never get a definitive answer unless the facts are tested in court. I would not rely upon custom and practice, or homespun opinion.

Peter Cook 602/04/2022 12:30:18
307 forum posts
88 photos

I am not a lawyer, but am aware ( from my days in academia) that there is a doctrine of "Fair Use" in copyright law which allows use of copyright material for a number of purposes including criticism, teaching, research, and study amongst other things - one of the criteria for many of the uses is that it should be non-commercial.

I am not aware that there is any similar defence in Patent law, but it is far from clear to me whether publishing a design is copyright law or patent law.

I would have thought ( and my view would be) that publishing the drawing on a forum such as this for feedback and criticism from other "experts" would have a valid defence under fair use non-commercial use.

Publishing the same thing on a Youtube channel in the expectation of creating income from the channel would probably fail the non-commercial test and therefore fall foul of copyright law. Where patent law applies I don't know.

Martin Connelly02/04/2022 13:31:11
2182 forum posts
227 photos

I agree with Dave, the money is what will determine the outcome. If you deprive someone of income by your actions then you could be taken to court for the aggrieved party to claw back lost income and costs. If someone creates a design and puts it out at no cost for others to make with no potential income for the designer then they may have no claim to be made for damages. It would however be polite to credit the designer and ask permission if possible (don't we all like a bit of ego tickling?) before publishing something based on the design. However if someone copies one of these free to use drawings then starts to sell them they are likely to have someone taking action against them for depriving the designer of potential income losses. After all the point of patents and copyright is to protect the income (actual or potential) of the owner of the patents or copyrights in question.

Martin C

Hopper02/04/2022 14:25:45
6690 forum posts
347 photos

It can boil down to three questions: 1. What can you do legally? 2. What can you get away with? 3 What can you do morally?

Question 1 will keep lawyers arguing until Doomsday and beyond, let alone the myriad bar-room barristers.

Question 2. You can get away with a fair bit if you are not making a profit out of it or preventing the owner from making his profit from it. Not worth lawyers coming after you for a few posts on a forum etc. Worst case scenario, you might get a "cease and desist" notice if you were taking revenue away from a commercial operation by publishing their intellectual property. So then you take your posts down and carry on.

Question 3 Well that is up to you. Morals are like that. If you get permission all good. If you are not making a profit from it, well ok. If you are not putting a dent in the copyright owner's business model, ok too. But publishing designs so forum members can avoid paying the copyright owner for the same material is a moral no no on par with Bit Torrenting music and movies etc on the old Pirate Bay etc.

Speaking of music copyright, even Donald Trump is currently caught up in that one. Reggae superstar of the 80s Eddie Grant is suing him to the tune (owww!) of $300,000 for pirating "Electric Avenue" in one of his election ads. You are unlikely to face that reaction to posting a toolpost drawing though.

SillyOldDuffer02/04/2022 14:50:39
8897 forum posts
1998 photos

Posted by Peter Cook 6 on 02/04/2022 12:30:18:


I would have thought ( and my view would be) that publishing the drawing on a forum such as this for feedback and criticism from other "experts" would have a valid defence under fair use non-commercial use.


I take the point, but the subject is a quagmire. For example, when joining the forum we all agree to MyTimeMedia's Terms and Conditions. Not bothering to read them is no excuse!

The fair-use non-commercial argument doesn't apply because MyTimeMedia are a commercial company, and, futhermore their Ts&Cs include:

You may not submit third party proprietory information to MyTimeMedia without first obtaining permission from the owner. Any Content provided by you by, for example, posting messages to bulletin boards or chat forums, uploading files, inputting data, or engaging in any other form of communication through this Website, although owned by you, is subject to a royalty-free, perpetual, non-exclusive, unrestricted, world-wide licence allowing MyTimeMedia to use, distribute, copy, sub-license, adapt, transmit, publicly perform or display any such content. You agree to irrevocably and unconditionally waive on your behalf in perpetuity in respect of such Content the benefit of any provision of law known as moral rights of authors or any similar law in any country.

My memory is dreadful, but I think the non-commercial / fair-use deal with academia was negotiated when cheap photocopying became available. I recall a lot of angst and aggravation about it in the 1970s. I believe fair-use is an accommodation, not the law.

Note MyTimeMedia's lawyers have protected themselves in the first sentence. 'You may not submit third party proprietory information to MyTimeMedia without first obtaining permission from the owner.' In the event I publish something on the forum that triggers a court case due to me not having permission, MyTimeMedia's defence is I have broken their rules as well!

They also own the copyright to whatever genius ideas I publish on the forum, so I have to be careful about that too,

In practice, not difficult to avoid trouble. I don't recall anyone ever copying and publishing a high value commercial proposition on the forum: if I saw one, it would be deleted to protect the poster. And, because we're almost all hobbyists, we have little need to protect rights we never intend to exercise.

At the end of the day, it's the author's responsibility to get it right. If copyright or a patent is likely to bite, get proper legal advice.


PS. Good fun that a publishing company like MyTimeMedia can't spell proprietory!

Hopper02/04/2022 15:13:20
6690 forum posts
347 photos

Looking at the websites concerned, I would not publish the MLA design. He is selling the drawings for $6 a pop so might be rather peeved if you were giving copies away free, even if you added your own minor mods.

If Harold Hall is already giving his design away free, he possibly would not object to you giving copies away free if they credit him as the designer and link to his site etc. But best to contact him and ask.

The floating clamp is an old and generic idea so no problems there.

"Fair useage" usually covers only a part of a copyrighted work, copied for personal, research, teaching or review purposes so not really relevant if you publish the whole design, not part of it, on a public forum so others can copy and use it.

John Haine02/04/2022 15:39:40
4718 forum posts
273 photos

It's worth looking at the site on copyright. Though the drawing of an item automatically has copyrights (in the UK) it isn't clear that an object made to the drawing does since the object may lie outside the class of things which are covered by copyright. The drawing of a toolpost is not a toolpost.

john halfpenny02/04/2022 15:45:55
253 forum posts
24 photos

Peter has mixed up a few concepts. UK law has a specific exception for teaching, which is not Calum's intention. As Hopper says, the exception relates to an extract, not the whole thing or a substantial part, and the criticism aspect refers to the extract, not a modified version thereof (which is what Calum has generated). Non-commercial use is often mentioned, but is a not a defence - copyright infringement does not require commercial loss to be proved, though it may be helpful to the claimant and guide a damages award.

Sometimes it is better to ask forgiveness than permission, but perhaps too late for Calum now. John is right to draw a distinction between the drawing and an article made to a drawing, but it is a very complex area of copyright law.

Edited By john halfpenny on 02/04/2022 15:49:20

Ron Colvin03/04/2022 12:14:43
81 forum posts
6 photos

The OP states that he uses OnShape to draw up his bits and pieces. He does not mention if this is the "Professional" or the "Free Subscription" version.

One of the conditions of the Free Subscription version of OnShape is that the data produced is publicly available. When using the program to construct a 3D model to a published design, even if it is only for your own use, Could this condition, have ramifications as far as copyright is concerned?

Nick Clarke 303/04/2022 13:11:37
1475 forum posts
64 photos

Some people have mentioned academia and teaching.

Without a legal qualification the rules I was given at several Colleges and schools include:-

If you write an academic article the copyright is yours.

If you write something to use as part of your employment (teaching) the copyright is your employer's (eg a worksheet for a class)

If you wish to use something for academic study you can use extracts only - 'Fair Use' - but this must be for academic study only and not because you just want to read the chapter or chapters. ie you cannot photocopy a chapter from someone else's HH book as that is the only thing you want to make.

If you wish to use something for teaching it can still only be an extract and in addition you will be audited by the Copyright Licencing people every so often during which audit you will have to list every thing copied within the institution and your licence is based upon this.

If you wish to change the format of something for access purposes you must have an original that you can then translate into braille or a voice recording - but you need an original for each copy you make.

Whether the last of these is the case for drawing up something that you have on a paper drawing as CAD sounds possible, but I suspect not.

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