"No mill is the same, especially a hobby one.
If someone was to take my file and simply mill it, I can be 100% sure it's not going to be the same as one I mill."

Than, either your file is not representing the actual measurements of the object to be milled (corrections for your machine's errors?) or other mills are less/more accurate than the one you're using? Either way, it defies the purpose of the whole CNC concept (accurate repeatability) which, I'm sure off, is what builders around here are expecting from the design.

The key to this all is probably creating 1 official resource where all the latest files can be found, plus sets of previous files (like version 1.0, 1.1a etc.) for tracking purposes. If errors are found it should be only one source (Mark and his great team) that make modifications to facilitate.

Whoever makes parts and sells them to others, is responsible for using the latest and greatest files and making sure his/her product will fit with the rest of the parts offered in OBPS or others involved.

 

OB spacer blocks ordered for ref and test fitting, I'm putting this one to rest

 

If machines could produce true identical parts, there would not be a need to specify acceptable tolerances ...

However, we are working within certain self imposed constraints which simply can not make two machines, especially with the many OX spin-offs, perfectly identical. There will be at least some slight differences in the end results. In fact, any single machine will drift over time, even with all the care in the world. The temperature/humidity changes (as my garage is getting much colder) will affect an end product ever so slightly ... The belts, the delrin wheels and any other part wear with use, add other factors like tool wear, spindle versus router, actual tool being used, the speeds used, ...)

The law of averages might be playing in our favour. Yet, at our level, our machines are not massive but they can be quite good, maybe not in my hands. I am certain there will be differences in the resulting part... The important aspect is whether the end result is within the set acceptable tolerances. Quality control will decide if the resulting part passes or not.

Definitely, the 'corrections' needed by a particular machine should not be made within a shared design. At least not without being very clear about what the correction consist of. Just like a shared design should not be the G-code itself.

We most definitely need a "reference" design, one which is always kept up to date. The files of which cannot be mixed into one or more builds or posts.

 

Yeah, Nugz! Here in Thailand they work mostly with trained monkeys, that's why I had to order my plates with Chris. Over here an error of 5% is looked at as 'very good job!'. Should I cry or should I hysterically laugh?

 

Good idea! Next time I try that tactics on one of these sorry monkeys. Maybe switching back and forth between the two a couple of times will really freak them out. Gonna be fun!

 

I'm a fan of the KISS system and are aware of the tendency of people to make things over complicated. Common sense would work best in this case and just one 'official' resource where everybody can get the plans and files will provide the uniformity we are looking for. The rest is up to each individual. Are you going for the 'official' plans or are you going for the plans and files of one of the builders? That choice will determine the result in the end. Everybody has his/her own responsibility to him/herself.

 

OK But which pile did I really need? That may be what a newcomer to the site thinks or feels. I am a cardholding Kiss fan Prauk and agree Current Standard Rev# of plans made also include Option_1 Plans Option 2 plans etc. with a read me included. Archive the older plans for administrators/collaborators to use as needed .
I have no doubt that the current plate builders strive for perfection. They also fill the custom change orders that builders want and end up with custom files which they may need to update so those files imo should be separate but its markings follow the Current Standard Rev. #s they apply to. Pointer links in the read me file If needed for those custom files.
I say this as a new member that has been looking hard at building a Ox. What makes perfect sense to you and me may not to the next John Doe in the door.

 

Let us not forget the gap between the machinist (the true professional) and the trained monkeys is quite large. I'm no where near either of those extremes and hopefully I'm heading towards the "machinist" end of the spectrum not expecting to be the pro some of you are ... In fact, that is not my goal. I just want to be 'pretty good' - my standards are high so 'good enough' is not for me.

Is the community here claiming to be only for the machinist ? I know it isn't for the pure breed train monkeys otherwise we would be in a very tight barrel. As much fun as a barrel of monkeys can be, I doubt I would be sticking around even then since I aim to learn.

Having said that, I'm not quite contradicting myself with my prior statement. As much care as I will take, I'll miss things, hopefully will get better not to miss the 'stupid' things train monkeys just don't care to watch out for. I'll achieve that from constructive feedback from the gang here, and elsewhere, but mostly here at this time. I'll also learn along the way by living the experience, knowing there is much to be learned. The train monkeys just don't care as long as the dry banana chips and peanuts keep coming. They'll buy a pre-fab hoping it only takes an unboxing video to get going as long as the main character has appeal ... (bad pun, eh ?)

With time, technology will make it easier for train monkeys to do the work. However, scarier still is that technology will one day make it possible to have no one at the controls just like the true machinists of days bygone could work wonders (for their days) by ear and feel ... So beware, train monkeys and machinist alike, our days are numbered. The replicator is not that far away ... Makers will survive, even if they are not the ultimate professionals with dead on perfect tools and skills.

A parallel thought : lots of people drive around in their cars and such without being professional drivers who, by the way, have an entire team behind them to make certain their vehicles are tip top 99.999% of the time as perfection is only a goal even for them. They still get into trouble (blow engines, etc.) Oh yes, there are way too many trained monkeys still "driving" around. But, guess what, technology is already making it possible for even a dead zombie to drive: cars with no steering wheel or pedals are hitting the mainstream market! You just have to be able to get in one of them, somehow grunt your directions and the car does the rest for you... Next thing will be for it to check your face, recognize you as the owner (you are no longer the 'driver') and it drives you back home ... that's if you are not already in your driveway or garage.

Anyways, controllable doesn't mean someone can't miss any one or more of the variables at any one point in time ... Tell me, you never made any scrap? You just became an instant machinist, one incapable of messing up, even if it is the fault of your machine or a defective tool which managed to pass through quality control, even yours ?? Or do you smelt your own metals and alloys to avoid those variables ? Then again, an impurity might sneak by and mess things up ... Keep that generator going, I hear the utilities have a wide tolerance for what is fed to anyone's location. Furthermore, as hard as they work, can't guarantee some trained monkey 'driver' won't take down a pole which feeds your location with the power your machine needs.

I hope I didn't burst anyone's bubble. I'm just a realist: things will happen that are beyond our control, no matter how good we think we are. We need to prepare ourselves as best we know and can. You might be better at that then me ... good for you. I'll try to learn off you along the way. I would rather learn from the mistakes of others (especially those more experienced then me) ...

 

Laugh as you have a better source and know better. But have a tear for those buying off the trained monkeys who still manage to make a living ...

 

The only way to freak a trained monkey out is to cut off the supply of dry banana chips and peanuts ... poor thing can't really care about anything else, can it ? He (she) won't even care if you stop showing up at their cage ... unless everyone else stops showing up as well !

 

I'd love to see an OpenBuilds Ox github repo with all of the design files in it, that way if a community member finds an error they can just issue a pull request and we can also create forks for things like myOx. This way we know that the master branch is always the most up to date reference version.

 

Eeehhhhh, I'm afraid that is a very true observation, Serge! It is exactly what happens.

 

Machinist or monkey, what we probably need is some kind of rudimentary organization of the build files and designs to suit our needs and that of future builders. Is it possible to come to some concrete plan and execute it?

 

I would suggest that you do not get too hung up on the term "machinist". By definition a machinist is merely a person who uses machine tools to either make or modify a part. By that very same definition most of us here are, indeed, machinists. [/QUOTE]

Sounds like we are on the same track, so no harm taken or done. As I had mentioned in earlier posts, I tend to think ahead of myself... I'm the type who will point out that there is more than two sides to a coin (can't forget about its thickness).

When I hear 'machinist', I think of people like my dad, who was a machinist / tool and die maker. It takes more skills to modify a part and still have it useful for the intended purpose then being able to draw lines, even in 3D space with a CAD / CAM system. Even more skills are needed to pick the right material and transform a piece of it from an idea to something useful. A machinist understands the properties of the raw material, how to best machine it, etc. You and a few of the other regulars seem there. I'm not.

For me to take a file for, as an example, the plates and move a few edges and add holes using CAD, does not make me a machinist nor will cutting such a new design into a material others have experienced with and basically picked for me based on their knowledge. I'll also use their experience to pick the tool, and follow charts to get to speed and feed rate, hoping my machine can do the job. I'll need much more experience, to gain confidence and to actually designing something new before I can think of myself as a machinist. It can be sooner than I think. Not forgetting that I am making a version of the OX. Three or so months ago I certainly wasn't thinking about making a machine. Finding the OX and this community certainly changed that. It's fantastic !

 

Very interesting all and so, Serge. But shall we try to focus on where it all started with? How to organize plans, designs and cutting files in a way that we have something to hold on to?

 

It's getting back on track. As PRauk mentioned, we need to figure out a way to keep the 'master' design as a clean reference model and track the variations without muddling files ... and threads. I've noticed a lot of the discussions go on in this particular build - even for matters of a more general nature. Maybe those need to be diverted to more of a forum type format, unrelated to builds/ressources ?

But in going through some of the existing forums, like general discussion, there is duplication, short dead end threads, etc. Typical of forums seen to date. It's easier to start a new thread than searching hundreds of existing ones ...

I believe Mark is also trying to figure out a way around the situation. I know he pays attention to what is being mentioned in many of the builds, if not all of them.

Maybe this is the point were this discussion spins off into a new forum topic ? I see the 'master' plates as a ressource, OB can keep the files updated (a .zip) while all can talk about the merits of doing such and such variations, even start spin-off ressources for particular versions (ex: the taller front X plate). Version control is built in. I would hate having to go left and right, to gather the pieces. I think newcomers would also prefer to see all related information here, in 'one' place.

I love what the team has done to this point - the site, the products, etc. But as more builds come online, the more difficult it will be to trace a clear line between them and the more general discussions. Something like the discussion around plates should probably go to a separate forum / ressource. Yet, we certainly don't want a thousand and one threads to watch ... nor everything crammed into a single one.

Sorry if I went off on tangents at times. But it is from discussions that ideas surface ...

 

Hi Everyone,

I have been through almost every page on this thread and am excited to start my Ox Build (thanks for the great design).

I am in New Zealand and am in the process of ordering my parts from makerstore.com.au.

I have got a couple of questions:
- Has anyone attempted to screw the X axis rails together for extra stiffness?
- The parts list specifies 20x40 for the Z axis rail, but I see that the assembly video shows the use of 20x60 rail, am I overlooking something here? Does the plate have mounting holes for v-wheels in either configuration?

Cheers
J

 

I think I had asked Robert about the Z axis rail sizing and his plates are sized for 20x60. I don't know if this is a standard as I am new to OB and like you starting
the process. Maybe the plate builders should answer this question to be factual.
As for bolting/screwing the plates, that would be the lesser weight penalty I wonder if adding 2 bars of cold flat plate, drilled locations one each side one side tapped would be better. Greater weight penalty and added cost.
The extreme wheels will carry a greater payload, I have been waiting to hear results in builds on how their working on larger X spans.

 

@slittle if you follow the build per the build video you'll find there is not much clearance between the x gantry plates and the 2060 rails. If you use plates either side of the extrusion to reinforce it you will need to add extra spacers. My machine is 1000 wide, so far I've only cut plywood in shallow cuts and it seems fine. When time permits i will probably bond the 20x60 rails together and use also use some screws to reinforce it a bit.

@Jeremy Young The original plate design accommodated both 20x40 and 20x60 for the z-axis, however in my opinion 20x60 is the better option.

 

asb_79 Yes it appears there's little room. I was thinking of running the stock inside the major void areas flush of the extrusion and drill for holes in one face to be able to fasten the hardware that way its a zero clearance on the face.
I would want to build at 1000mm wide also and bonding is in my plan when I do build. My biggest concern is adding the weight to the gantry.
Asb_79 btw those waterjetted plates looked awesome nice job. Keep me up to date when you bond those beams. thanks.

 

Thanks for your replies @slittle and @asb_79 .

Yep I managed to figure out that there was the option of 20x40 or 20x60 for the Z axis after making that post

For the x axis (gantry) I had planned to drill through one rail, tap a thread into the other and machine a recess in the side of the rail for the screw head. Kind of hard to explain but I suppose I will get a better idea of whether it is possble once I start building.

I have managed to find all the parts except the 20T GT3 Timing pulley and 5 hole 90 deg joining plate! Anyone know of a seller willing to ship to NZ?

J

 

I ship world wide. .. even New Zealand... send me an email at [email protected]

 

Another thing I noticed is that "Ox plates" are mentioned twice in the parts list.

And "5 hole 90 degree corner plates" are also mentioned, but these also seem to be included in the Ox plates cut file?

Am I missing something??

 

If you are looking at a file I posted the 5 hole plates are included only because it was easy for me to have them cut at the same time as the gantry plates.

 

Hi Jeremy, what part of nz are you from? I have a working Ox in Auckland if you wanted to see one up and running to help you along with your design. If you need vslot parts just let me know as my first bulk order should finish customs processing later this week.

 

The following pertains to my plates only, I can not speak for any others that have provided plates

It has bin confirmed the the Z axis spacer block "mounting holes on the X plate only " need to be drilled with a 13/64 bit taking them from 5mm to 5.1mm
This is something that I used to do to clean up the holes to make them true circles and why I never had complaints , I increased the poly count in sketchup thinking this would clear the need for post drilling but has caused the compatibility with OB spacer blocks to arise.
So a good thing and bad has come of it, thank god it's a simple fix folks.
I will be correcting the file as soon as my spacer blocks show, about 2 days out

 

Feel like I just walked into a whirlwind. I was about to order some more garolite, and figured I better check the site for any updates. I'm glad to hear that Openbuilds will be providing some plates for one stop shopping.

Kram, what materials will you be offering?