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Don't ask why, don't advice to buy one.
Tell me how to build one.
There was a troll at a different forum and my thread got locked.
Anyways, with all the trolls put to the side, how can I build a commercial grade 5-Axis CNC lathe?
4ftx3ftx3ft is that a practical size for a 5-Axis CNC for hobby use?
Tolerance of +/- 0.001mm
How can I make the cast iron base from scratch?
Water cooled ball screw, how much do they cost?
What would be the practical steps in building one?
Thanks
Hello.
I know it is not quite the answer you expect but I think it´s important that you read this.
It is quite possible to make your own machine but you must consider a series of facts.
First, you must understand that the cost involved in making it will generally exceed that of buying one.
Second. Since you are talking about building a machine from scratch a large number of calculations are involved.
What you are asking for are all the engineering and production information and I sincerely don´t expect that someone will graciously give it away. It´s like asking any machine builder to give that information to you.
Third. It´s irrelevant if you want to build one machine or a million.
Fourth. If you really want to build an industrial grade machine you are required to be willing to pay for all the work from the concept stage, design, prototype, casting, machining, etc. that will be required and that will certainly not be cheap.
Having said all that I think it should now be quite understandable why the DIY wave has gained so much popularity as for small shops and hobbyists alike it offers the possibility to have machines with generally reasonable quality at relatively low cost compared to professional machines.
At this level production capacity is generally not a big issue and thus small production orders can be served with good efficiency.
One last comment in reference to your request,
I suggest that you first decide what type of parts you wish to manufacture. That´s important if you decide to go DIY as that will help determine things like the structure of the machine, that is, steel or aluminum, cast or machined. The type of motors, servos or steppers. The transmissions, ballscrews or leadscrews, gears or time pulleys.
So you see a number of decisions are to be made all to solve some particular manufacturing need.
Professional machnes are designed to solve as many requests as possible. That´s one of the reasons they are expensive.
There are a number of places in the internet that can give you ideas to build DIY machines of all kinds. You can take a look at INSTRUCTABLES, OPENBUILD, etc.
I hope this helps, somehow.
Regards.
I will PM you thank you for the reply!
Move your tolerance number one decimal place and it becomes realistic. Machines like the kern for example have years of development and very sophisticated temp control, still I think they only claim 2 micron tolerance. 1 micron on a diy machine just ain't gonna happen. With top notch gear and some thought into the design, maybe 5 micron.
This forum website is really weird... seems like there's a new version of this website. I sent a PM and it didn't go through when it originally told me it did.
I sent messages on the newer website.
I'll message you too QuinnSjoblom. We should all have a group messaging system, I like how there are people who actually knows about this subject, knows that with the help of math, science and software, crazy stuff are possible.
Has anyone received the messages?
I did. Did you receive my reply?
Hello Raj - The closest commercial machine to your specs is the shopbot 5 axis. Do you mean mill? not lathe? https://www.shopbottools.com/products/5axis its price is $43000USD. The mechanicals although a bit more complex than a 3 axis mill are do-able but the software is very costly for 5 axis machines. To answer your questions:
1) a 1um machine requires toolmaker grade machines to make it and it has to live in air conditioning to maintain the accuracy. A hobby machine will be 0.1mm maybe 0.01mm. The shopbot claims 0.01mm step resolution which may not give you 0.01mm accuracy probably 0.1mm accuracy
2) To make a cast iron base find a foundry, design the base and get them to cast it. Quite simple
3) water cooled screws speak to THK, SKF or any of the top ballscrew makers. Be prepared to sell your arm or a kidney maybe your house
4) Practical steps a) get a good cad system and start designing 2) your first attempt will take at least 500 hours 3) then you do your second attempt another 300 hours 4) then you are at your 3rd round and it will start making sense. Then you have to do all your manufacturing level drawings and send out to foundries and machinists. Plan on about one to 1.5 years of work to get to a costed fully detailed machine at hobbyist level hours available unless you don't sleep
5) Then you can get your check book out and start ordering all the parts and wait. Then when they are all in you build it
6) It's a great hobby. I do not jest about these numbers. I've done this several times and I design bespoke machinery for a living... there are several threads here with very nice 3 axis machines and you can look at the dates and see how long, long they took to design and or build their machines some of which at about a year they give up or park the project. Its a long haul....
Regards Peter
Not all steps by steps, but almost..
A home made high-precision 5 axis from basement to table.
Unfortunately other users pushed in theirs post so you have to walk back in time...
https://www.facebook.com/groups/961660174215024/
That build by Allessandro Belloni is pretty cool! Thanks for sharing!Quote:
Originally Posted by shineworld
You're getting free advice, not always good to come across as rude if you want people to help you. Many of the questions, such as "why" help people to understand what size of a machine you want. People are still wondering if you want a mill or a lathe because your post was a bit contradictory. They also don't know what kinds of metals you want to cut.Quote:
Originally Posted by rajhlinux
I'm going on the assumption you want a lathe. Also from some of your other posts here, I will assume it's to make custom air and water fittings, perhaps 2" diameter by 3" long at max.Quote:
Originally Posted by rajhlinux
I'm going to make a guess here. You borrowed that number from an advertisement somewhere. On some cheap machines, like 3d printers, they will tell you what the maximum theoretical resolution of the stepper motor is using maximum microstepping. For example, a 1.8 degree stepper, 200 steps per revolution, with a 5mm lead screw and microstepping of 25X..... 0.001mm = 5/(200*25). But this is NOT the tolerance of the machined part. It's just a theoretical number.Quote:
Originally Posted by rajhlinux
0.001/25.4 = 0.00004" Even the tinyest amount of runout on your spindle will destroy that tolerance, even if you had the best precision ground temperature controlled everything.
Based on your other posts on CNCzone (I never tried to find the ones from any other forum), you mentioned a tight budget of $5000 for this project.....so in other words you don't have a clue what you are asking about. And that's OK, because we all start somewhere, so don't take it personally :). I ask about things that I don't have a clue about all the time, but that's how we start to learn.
Unless you have a budget of at least several hundred thousand dollars, and an experienced machine designer to design and build this for you...the tolerance you have asked for is not going to happen. And even with those things....
A better question would be to tell people what you want to make and ask what is an appropriate tolerance to aim for in your machine design. Let's just say 0.05mm or around 0.002" for argument's sake.
Write an email to the sales department of one of the companies that makes them and ask. Tell them the tolerance you need is 0.001mm. Then report back and tell us how much it would cost. You will quickly see if we are telling you BS or not.Quote:
Originally Posted by rajhlinux
First you need to do a general design of the machine based on other machines that work. Without that, you have nothing. Are you good at drawing things in CAD? Your lathe would need to be servo driven. You would need a low backlash harmonic drive or planetary gear for rotating your spindle (EBay). Let's say size 25 linear rails, and 20mm OD ballscrews, clearpath size 23 servos for your X, Y, Z, and Rotate. Start drawing with that.Quote:
Originally Posted by rajhlinux
Also, look at modifying an existing lathe to CNC and adding your X, Y, Z, and Rotate to that. Draw it up. Something with a feed through chuck is going to be alot less wasteful for materials.
I'm not aware of any open source designs for this, but do some searches on sites like grabcad.com etc., you should be able to find drawings for alot of parts.
Then you come back with a design, post pictures of it, and ask questions about motor sizing, ballscrew lead, gear ratios, general feedback on stiffness, tolerances, ability, etc.
So the question you should be asking right now, is if anyone has any examples of good machine designs for 5 axis lathes for you to start basing your design on. And if you go down this road, be prepared to spend more than $5000 and you will never achieve tolerances of 0.001mm. Never ever.
I came across this machine on youtube....perhaps you can use some of the concepts of this design when you are drawing up your own. There are some obvious problems with the design, IMO, like aluminum ways, you would want proper linear bearings instead, and I'm guessing it doesn't have very good gearing, but that's why EBay exists. Also, consider that making parts from solid aluminum stock, bolted together, is way easier than working with steel, and it generally comes quite flat. What access do you have to large machining centers right now?
https://www.youtube.com/watch?v=k5zsQ5irMsg
This video is from a failed kickstarter campaign. They promised the machine for $4700 USD, it was obvious to me seeing that, that this would fail.
If you are looking at this machine as production for a business to make a profit, then IMO, you are going about it the wrong way.
To give you some perspective, the DMG MORI NTX 3000
https://www.youtube.com/watch?v=pXWU...re=emb_rel_end
https://us.dmgmori.com/resource/blob...0-pdf-data.pdf
claims to have an X Y Z plane milling accuracy of 2.2 um, or 0.0022mm.
Hello.
I decided to write a post in the open so that others may gain some knowledge out of it.
First I will have to ask you about your concept of "hobby use" so that a difference to "professional use" can be established.
Let me elucidate.
As far as you have posted you require an industrial grade machine but for hobby use.
It´s like saying that you want a Rolls-Royce to make your weekend shopping.
A Rolls-Royce is a Roll-Royce no matter what you want it for. Either for touring, weekend shopping or just to park it outside your house it will have the same price. What I mean is that the use does not affect its price.
Given the proper distances it´s similar to one of my customers asking me to design a new quilting pattern but that he will need it for a single run. The work to do the design is the same. It is his problem to pass that cost on to his customer or not. Not mine.
Back to your request please answer the following questions.
1. How many machines do you intend to manufacture? How many per year?
2. What is your target price?
3. From the buyer point of view, what will you be offering that other brands do not have?
4. For the given characteristics and specs, why should a potential buyer decide on your unknown brand over some reputable brands?
5. What training services and tools will you be offering?
6. What warranty will you be offering? What are its policies? For how long? At what price?
7. What service and manteinance procedures will you be offering and at what cost?
8. Will technical support be available? Will it be for free or for a fee? For how long?
9. Will spare parts be available? What is the intended delivery time?
Note: for this one you will have to have an analysis of the parts more likely to wear out and have some stock of them.
10. Will the spare parts be standard or OEM?
Note: OEM, Original Equipment Manufacturer. In this case applies to parts either manufactured specially for you or parts that you make.
As I mentioned before you have to define some of the logistics from the very beginning. Even before actually doing anything with the machine itself.
From analysis such as that it is that we decide how viable a project is.
Remember that the more machines you manufacture the lower the cost but in doing so other costs may have to be added as for example more capacity to manufacture the parts or take them back to be manufactured in-house rather than have them manufactured at external shops.
When you have those questions answered please post them or PM me if you consider it necessary.
Regards.