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View Full Version : Need Help! Questions about a new build



bandtank
09-27-2009, 12:28 PM
I've been lurking for quite some time and finally decided to join these forums a few minutes ago. I have background in this area but I've never built a DIY CNC machine before. After looking at all of the possible choices, I am currently leaning toward a Joe's 4x4, but I have a ton of questions as the website is sorely lacking in information and these forums do not have a centralized place for a first timer to gather all of it by themselves. I'm not trying to be rude or anything, but it's true I think.

Anyway, concerning the Joe's 4x4, here are the questions I have. If anyone has the time and patience to answer some of them for me I would greatly appreciate it.

1) First and foremost, the plans on his website are extremely mysterious. There is no information available about what the kit provides and what it does not. Yes, there is a picture, but that's it. If I were to buy that kit, what would I be lacking in terms of the physical structure? All I can tell from the picture is it obviously doesn't come with the extrusions, but I have no idea what else is missing and I'm not going to spend $100 on plans to find out I need another $500 worth of parts on top of the kit to simply build the structure.

2) If I were in fact going to buy the plans, do they provide answers to all of the questions like "what leadscrew do I need?", "what motors should I be using?", "what controller do I need?", "what router do I need?", etc. etc. If that information is not provided in the plans, then what do the plans actually do for me other than give me a list of parts that I already bought in the kit and forum access? The bottom line is if I pay $100 for a set of documents I want it to have 'all' of the answers to basic questions and I'm wondering if someone can verify this for me.

3) I know the information I want in question 2 is available in the forum, but as I said in my introduction, there is no centralized place for a newcomer to find any of this, or at least there is no obvious place that I've seen. Is this the case? If yes, where is it since I've obviously missed it? If not, I will be writing something like that in the near future as it would have saved me a great deal of time and frustration.

4) Is there an exact BOM for a 4x4 somewhere on these forums? I looked through some build logs and never found anything very concise, and my wife will not be happy if I start this project thinking it's going to be X dollars and it ends up costing X*2 dollars instead. I mean a complete example build including the kit, motors, controller, hardware, router, etc. etc. I'm assuming this is what is included in the purchased plans, but I'm asking if a free one exists so I don't have to spend $100 on plans to find out the whole project will be too expensive.


I know there are variables and options, but I'm asking for real numbers from real examples. I am a DIYer but my first objective is to build a cnc machine and use it, not to have a lot of fun playing with the design if that makes sense.

I am not trying to sound rude or abrasive. Please let me know if you are able to provide any answers to these questions or any information at all. I would definitely appreciate it.

Hdale85
09-27-2009, 01:49 PM
The kit only provides the MDF and HDPE parts. All the aluminum extrusion, steppers, drives and so on you have to purchase. Generally a completed 4x4 is ~2500. The 4x4 is a paid design meaning you have to purchase the plans. After you purchase them though you have access to his private forums which from what I understand hold a wealth of knowledge.

The BOM for the 4x4 is in the plans as well as pretty much every question you are asking here is either in the plans or quickly answerable by Joe him self or via his forums. Every part you need is in the plans though. I believe he gives you the length of ballscrew you need but not a particular one as it's going to depend on what you want.

ger21
09-27-2009, 01:50 PM
1) The kit. What you see in the picture is what you get. Yes you'll need at least another $500. As a guess, I'd say about $2500 total. But I haven't seen the plans. The kit is just the wood and plastic parts. The majority of the machine is metal, and not included in the kit.

2) yes, they should have all the info you need in them. They all grant you access to his private forum, with about 70 (just a guess) people who have built or are building the machine. And all the modifications made by those people as well.

3) thee's no simple place to find all the answers. I always recommend spending at least a month reading as much as possible, and learning along the way.

4) I don't think so, but it's included with the plans, and again , probably available on the private forum.

Unfortunately, due to his private forum (which is to protect the design), you won't find much info about it here. But I can tell you, that a lot of people built his 2006 machine, and then went on to build the 4x4. Everyone I've seen post about it has been extremely happy with it.

Keep in mind, though, that CNC is not cheap. You have a lot of options available, and can easily spend up to $4000 on the machine alone, and at least several hundred more on software. If you're just getting started and looking to do it cheaply, a small "learning" machine might be a better option.

Hdale85
09-27-2009, 01:59 PM
Hah you can easily spend more then 4k on the machine :) Heck if you decide to go with a spindle you could spend 4k just on that part. But it can be done for less although maybe not quite as nice but will still be very capable.

I agree if you aren't really sure how serious about the machine you'll be the 2006 or some other kit similar might be a better option.

bandtank
09-27-2009, 02:52 PM
Thanks for the replies everyone. Very helpful information.

So the 2006 is easier to build, cheaper in the end, and still produces quality results, right?

I should have stated this in my OP, but my goal here is to be able to cut relatively small things (around the size the 2006 can handle) with decent precision, and a large emphasis on cost efficiency. I am not opposed to $1000-$1500 in the end, but $2500 is too much for my first one considering I will most likely make a lot of mistakes.

If I go the with the 2006 and buy the kit, what else will I need to buy to complete the structure? Maybe someone can tell me if this is a bad idea, but I was hoping to just purchase the kit, put it together, learn how it works, and then start adding a few pieces at a time after lots of research. Will this work?

I'm not interested in rushing...slow and steady wins the race. I don't want to get in over my head and have this thing sitting around half finished for 6 months. I've got a newborn baby and I would love to start making her some stuff before Christmas, which I think is reasonable but maybe I'm wrong.

Again, thanks for all of the input.


Edit: I'd like to add one other thing. I'm not particularly interested in high IPM. I am more interested in the other side of that spectrum - precision. I know there is a fine balance between the two so hopefully the 2006 can achieve good precision especially if I buy ballscrews with high TPI.

Hdale85
09-27-2009, 04:01 PM
The 2006 is quite precise (as best you can get probably for an MDF router). It would be great for wood parts and maybe the occasional aluminum or something.

The 2006 kit comes nearly complete as far as the structure goes. You just need the metal rods for the bearing slides and what not. Of course all the electronics. Some people have built the 2006 as little as 1k bucks but I'd say 1500 is a pretty good budget for it.

ger21
09-27-2009, 05:38 PM
Edit: I'd like to add one other thing. I'm not particularly interested in high IPM. I am more interested in the other side of that spectrum - precision. I know there is a fine balance between the two so hopefully the 2006 can achieve good precision especially if I buy ballscrews with high TPI.

Imo, most people that say they don't need the speed don't know the importance of it. With a router, you need to be able to have decent speed to prevent burned wood and dull bits. Slow speeds cause heat, which causes bits to dull.

Just buying ballscrews will not necessarily add any precision, unless you spend more than your budget on the screws. And then, you must still be able to build a machine to very precise tolerances. The multi start acme screws that are commonly used, are typically just as accurate as the cheaper ballscrews, and still a lot cheaper. Repeatability is what you're looking for, and .001-.002 is not that uncommon, provided everything is tight. 1/2-8 2 start acme is fairly inexpensive, and is capable of 150-200ipm speeds with the right motor/drive combination.

Now, I've never built either of Joe's machine, and have never seen one in person. But, I'm not sure that the 2006 is easier to build. the 4x4 is basically a bolt together kit, while the 2006 requires a lot of glued up assembly. If not glued up properly, you could have some trouble.

As for cost, look here. http://www.cnczone.com/forums/poll.php?do=showresults&pollid=169
Over $1500 was the most common answer. But if you plan carefully, you should be able to do it for $1500.

In addition to the kit, you'll need leadscrews and nuts, electonics and motors, all the bolts, washers and nuts, the gas pipe and the bearings that ride on the pipe. Basically, everything not made of wood and plastic. It's best to buy all the nuts and bolts in bulk at one time, or you'll easily spend up to 5 times more running to the local hardware store or Home Depot to grab a few here and there.

Getting it done, and learning how to use it before Christmas?? How much free time do you have? I'd say 3-4 months is normal for the build. I've seen machines finished in a month, but there's a lot of little things that can take a lot of time.

bandtank
09-28-2009, 12:56 AM
Imo, most people that say they don't need the speed don't know the importance of it. With a router, you need to be able to have decent speed to prevent burned wood and dull bits. Slow speeds cause heat, which causes bits to dull.

I have some experience with a router. I've cut miles of acrylic and spent plenty of time melting it before I figured out the correct feed rate. I'm just not interested in high speed is what I'm saying. People in other threads have been asking about high speed, e.g. 300+ IPM, and that is faster than what I need. If my machine ends up being capable of it, then great, but what I'm saying is I don't care either way. That's all I meant, not that I don't understand that there is a less than sufficient speed for different materials.



Just buying ballscrews will not necessarily add any precision, unless you spend more than your budget on the screws. And then, you must still be able to build a machine to very precise tolerances. The multi start acme screws that are commonly used, are typically just as accurate as the cheaper ballscrews, and still a lot cheaper. Repeatability is what you're looking for, and .001-.002 is not that uncommon, provided everything is tight. 1/2-8 2 start acme is fairly inexpensive, and is capable of 150-200ipm speeds with the right motor/drive combination.

Yes, repeatability is key for me and a tolerance of .001 would be great, but I am not naively optimistic about my first build. If I could get my router to +/- .01 I would be happy for a first go. To me, that is 'precision' for my first attempt. Subsequent machines will need to be within .002 or less for what I plan to do with it. That will be sometime next year. I haven't looked at prices yet but the 1/2-8 2 start was one of the choices I'd been considering. I've also been looking into the 5 starts as everyone on this forum, or at least in the thread about this particular issue, seemed to really like them.



Now, I've never built either of Joe's machine, and have never seen one in person. But, I'm not sure that the 2006 is easier to build. the 4x4 is basically a bolt together kit, while the 2006 requires a lot of glued up assembly. If not glued up properly, you could have some trouble.

This is what initially attracted me to it, but it's simply too expensive. The 2006 or possibly another similar design is all I want to do on my first try. I would prefer the 4x4 but its about $1000 too much.



As for cost, look here. http://www.cnczone.com/forums/poll.php?do=showresults&pollid=169
Over $1500 was the most common answer. But if you plan carefully, you should be able to do it for $1500.

I saw this a few days ago. I will most likely be building my own motor driver and I have several spare steppers. As I said, I am not new to DIY, just new to DIY CNC. I suppose I could have been more clear about that in my OP.



In addition to the kit, you'll need leadscrews and nuts, electonics and motors, all the bolts, washers and nuts, the gas pipe and the bearings that ride on the pipe. Basically, everything not made of wood and plastic. It's best to buy all the nuts and bolts in bulk at one time, or you'll easily spend up to 5 times more running to the local hardware store or Home Depot to grab a few here and there.

I was planning on buying the pieces I need for each step in one fell swoop other than odds and ends that I may need during the building process. I definitely understand what you are saying about getting raked over the coals if you start buying the bolts one or two at a time. Thanks for the list of the other materials. I am familiar with everything except the bearings so I'll need to do more reading about that.



Getting it done, and learning how to use it before Christmas?? How much free time do you have? I'd say 3-4 months is normal for the build. I've seen machines finished in a month, but there's a lot of little things that can take a lot of time.

I've used CNC machines for years. I've just never built one from scratch is what I was trying to say. I have enough free time to build it, but not enough free time to mill and lathe all of my own parts because I have a 3 week old baby, which is why the kits are attractive. I was in the process of making her something on the mill, but I decided I'd like to just take the plunge now and get the CNC machine up and running. I worked on the sales pitch to my wife for about a week and she took it hook, line, and sinker. Now it's just a question of ordering what I need and getting started. I am planning on being ready to order all of the parts in about 2 weeks. Thanks a lot for your reply and all of the information. It will definitely give me some things to think about and research this week.

ger21
09-28-2009, 09:06 AM
Yes, repeatability is key for me and a tolerance of .001 would be great, but I am not naively optimistic about my first build. If I could get my router to +/- .01 I would be happy for a first go. To me, that is 'precision' for my first attempt. Subsequent machines will need to be within .002 or less for what I plan to do with it. That will be sometime next year. I haven't looked at prices yet but the 1/2-8 2 start was one of the choices I'd been considering. I've also been looking into the 5 starts as everyone on this forum, or at least in the thread about this particular issue, seemed to really like them.


.01 should be easily attainable. 1/2-8 2 start will give double the resolution of the 5 start, but lower speeds. The homebuilt drives and motors you use may greatly influence the performance you can get with them, though. With an old Xylotex drive, I get a reliable 150ipm from my dual driven X axis, and 175ipm on my Y axis.

bandtank
09-28-2009, 03:42 PM
.01 should be easily attainable. 1/2-8 2 start will give double the resolution of the 5 start, but lower speeds. The homebuilt drives and motors you use may greatly influence the performance you can get with them, though. With an old Xylotex drive, I get a reliable 150ipm from my dual driven X axis, and 175ipm on my Y axis.

I'm wondering what your opinion is of the Fineline Automation kit. It seems to be well built and well received, but I'm not completely sure yet. The price is also a lot more 'known' than the 2006 or 4x4.

ger21
09-28-2009, 04:58 PM
Never seen what it looks like. I can tell you that the bearings it uses from www.cncrouterparts.com seem to work very well, and everyone that I've seen using them is very happy with them.

Hdale85
09-28-2009, 05:39 PM
The Fine Line kit is one I've considered as well. Although honestly it's not going to be much cheaper then the 4x4 if any. They are both constructed out of 8020 extrusions. The Fineline kit is a bit smaller though (although shouldn't take much to scale it up a bit if you wanted).

bandtank
09-28-2009, 06:12 PM
The Fine Line kit is one I've considered as well. Although honestly it's not going to be much cheaper then the 4x4 if any. They are both constructed out of 8020 extrusions. The Fineline kit is a bit smaller though (although shouldn't take much to scale it up a bit if you wanted).

How would they be the same price? People have been saying the 4x4 is $2500 and this kit is $1300. The electronics and router would add another $500 or so and then shipping would be another $100. That is $500 less or am I missing something?

I've considered not buying the entire kit from Fineline so I could get longer extrusions to scale it up slightly.

ger21
09-28-2009, 06:52 PM
I've considered not buying the entire kit from Fineline so I could get longer extrusions to scale it up slightly.

You'll need to get longer rails as well as extrusions.

bandtank
09-28-2009, 06:57 PM
You'll need to get longer rails as well as extrusions.

By rails do you mean the motor drive screws? I don't know exactly what to call them, but the acme/ballscrew thing.

ger21
09-28-2009, 07:10 PM
No, but those too. :) You'll need longer extrusions, longer acme screws, and longer cold rolled steel rails that the bearings ride on. I think it's 1/4" x 3"??

Hdale85
09-28-2009, 08:05 PM
Well 2000-2500 fall into the same ballpark. Also you are losing some cutting area so price per cutting area is pretty close to the same.

matt-CNC
09-30-2009, 05:32 PM
No, but those too. :) You'll need longer extrusions, longer acme screws, and longer cold rolled steel rails that the bearings ride on. I think it's 1/4" x 3"??
How could you make Joe's 4x4 into a 4x8 machine? After reading what you posted it made me think about making Joe's 4x4 longer, so I made a new post. Let me know what you think.

http://www.cnczone.com/forums/showthread.php?p=672638#post672638

joecnc2006
10-05-2009, 12:07 PM
Here are just a couple of 4x8 machines built, The X-Axis has rack and pinion drive. As always you can see the machine which people have built on the webpage. www.joescnc.com in the galley section, this will give you an idea and examples of what people are building DIY wise now.

matt-CNC
10-05-2009, 12:38 PM
Here are just a couple of 4x8 machines built, The X-Axis has rack and pinion drive. As always you can see the machine which people have built on the webpage. www.joescnc.com in the galley section, this will give you an idea and examples of what people are building DIY wise now.
That makes a lot of sense, extending the X-Axis on a R&P drive, since you will only have to do that in one place (instead of two places on the Y-axis, right?). I am doing research now on how to adapt the X-Axis to the R&P system.

D.lusty
10-23-2009, 10:31 PM
Sounds great. Feel free to post any additional questions or queries that arise - were happy to help. Please do keep in touch to let us know how you get on.

John Essential Project Team