Hi all,
I've been wanting to build a CNC router for a while (actually, I've been between a router and a foam cutter). Today, I found free plans for the JGRO machine so a few questions came up:
1. Somewhere (maybe on another forum) I read that it required basic woodcrafting skills. Being 14 and not much into that (although I do make R/C airplanes) I don't think I have that kind of experience. My dad, however, may. What do you mean by those skills?
2. Interpreting the plans :stickpoke
I haven't had a deep look at them yet but they seem complex (for me, that is). Where should I start, or where should I ask someone where to start :P?
3. What can I do with it? This isn't that important, but I'd like to know the possibilities.

Some books to learn these things would be great (instead of asking you all the time :)

Thanks in advance,
Ignacio

I'm guessing your going to school if your school offers a shop class i would take any courses they offer. Nothing is better than education. Talk to friends and family you maybe surprised on what kind of help they can be. The biggest part is being patient somtimes you'll run into a hard spot that will stump you for a long time and after you figure it out you'll be thinking why didn't i think of that right away. The best advise i can offer is read all you can in these forums and surf the web they are of the biggest help to me. For the what you can do with it depends on how you make it if you make r/c planes you could design you plane on a computer and have the machine cut it out which is convient if you crash a good plane design so you can make another one or just make modification to it.

No, we don't have a shop class... still, my dad's company has quite a few tools, some people with experience and I know a surplus printer/scanner/etc. parts shop.
if you make r/c planes you could design you plane on a computer and have the machine cut it out which is convient if you crash a good plane design so you can make another one or just make modification to it.
Amazing...
By the way, can the that router cut metal? Cause if it can, I've got some uses in mind (making engines :)



Okay, that was a bit ambitious

You build airplanes for a hobby, and you're worried about this?! ;)

For the most part you need to be able to cut wood/MDF, and have the resulting cut be square and straight. Having it end up the right size helps, too. It also involves some minor "machining" type of work, like drilling holes with reasonable precision.

I didn't build a JGRO unit, but the basic construction is pretty similar on all of them.

These machines are pretty simple, mechanically...take a look around this site. LOTS of pictures. You'll notice just how simple they really are, when you start really looking.

Look also at the solsylva (sp?) machine...it's inspired. One of my current favorite designs, primarily because of the fully supported rails. Supporting the rails addresses a LOT of the problems with the other designs.

http://solsylva.com/cnc/1aplanshome.html

-- Chuck Knight

You build airplanes for a hobby, and you're worried about this?!
Well, model airplanes, I don't think they're harder than doing this :D
Regarding the plans on the link, it seems like a nice machine but adding $30 to an already expensive project, while it could be done for free...
There is a Home Depot here, problem might be looking for non-metric stuff... also, I'm, not that precise while cutting ¬_¬

Update: My dad needs it to have a precission of 0.01mm, for making PCBs
:eek:

By the way, turns out there's another Argentinian building a router (peu)

I didn't mean for you to *necessarily* buy the plans...just to look at the finished machine, and get creative. He is a member of this forum, though, and he would probably appreciate the purchase.

His use of fully supported rails is a VERY good idea. Sagging and sway in the pipe rails is one of the primary weaknesses of many of the homebuilt machines...this is a very elegant way to address it. Simple solutions are often best.

-- Chuck Knight

Ok, my main issue now is where to start. Peu seemed to design it with some CAD program, and afterwards built it. However, I think he had ordered some parts before having a finished design. I'll PM him asking about the design, and see whether I can come up with something.
I just hope there's a hardware shop nearer than the home depot.. anyway, I'll see if I ask my dad for books on mechanics and design.

...it's inspiredwoohoo! Everybody loves a compliment :D
As Chuck said there are tons of ideas and pictures out there, mixing and matching ideas from what you find is often the best route to follow if you have the time to trial and error through the design.
A CAD program is unnecessary and can slow down the process for some of us. Working with real parts or cardboard and hot glue can help find problems and solutions that are not obvious in the virtual realm.
The 0.01mm precision will be tough to hit with a machine that has any wood in it and without a reasonably well equipped shop that target becomes unrealistic.
Maybe consider starting with a super cheap machine made from printer parts, do not worry so much about accuracy at first, just become comfortable with the concepts. I really think you will be disappointed if you try to start with a 0.01mm accuracy machine unless there is somebody with knowledge and tools who can help.
Good luck!

I liked the idea of starting with a simpler machine. I found a local distribuitor. I thought about using a CAD program because I didn't want to spend lots of money to test things which might, later on, not fit together.
By the way, the distribuitor has all the things peu bought from the USA.. let's see whether they're cheaper (I hate websites which don't list prices!!! :mad: )
By "reasonably equipped shop", you mean with reasonable equipment (and what would that be), experienced people or both :P?

Edit: I just thought... peu's first router had the accuracy I want. Is it possible for me to achieve it too?

Hola Ignacio,

Forget about local shops, I asked prices for linear rails and they are simply NUTS, about u$d600 for a 500mm THK rail with a single block. Same with motors, same with ballscrews...

My suggestion if you want to start cheap, build a simple MDF (fibrofacil) and tubes Jgro router, some spare steppers from surplus laser printers or copiers and learn the trade.

Then you can make a more precise one so your dad can drill PCB's :)

Or, if dad helps :) go for the precise machine, but let me tell you that precise does not come cheap...


Pablo

Since you mentioned PCB routing, this is a planset for a machine specifically designed to route PCBs.

http://www.crankorgan.com/brute.htm

Sorry about linking to *his* site, guys...but it's a perfect answer for his question. This machine is designed around routing PC boards...it's simple to build, and according to all reports it works quite well. In fact, many of us who are homebuilders were directly inspired by one or more of *his* ideas and designs.

Show the pictures of these machines to your dad, and realize that this one makes extensive use of extruded aluminum window channel. It's "commonly" available in the USA...not sure if you have something similar in your country. It's a large extrusion (4x6" in cross section, for the extrusions I have in the garage) in the shape of the letter C...lets you use simple parts to slide around on the extrusion. The sliding parts are plastic, and fit *around* the edges of the extrusion. Viewed end on they resemble a letter H.

That should be enough of a hint for you, without giving away all of his secrets...

Like I said earlier -- don't be afraid to get creative. There is a wealth of information and expertise on this site, and we're all VERY willing to share it.

Seriously, though, here's some free advise -- build a simple and small machine first. You can reuse the expensive parts like the motors and circuitry on machine #2, and use the smaller machine to build the precision parts for the bigger machine. Your biggest enemy will be flex...and it's easier to keep small machines from flexing.

-- Chuck Knight

If I do build one, it'll be a smaller one as you said. I can't buy used parts from abroad because my dad says they can't pass through customs. Additionally, it either costs a lot from multiple shippings, or it's a single one and I have to hope parts will fit. I'll see if I find a local solution (MDF and tubes like like peu said), or drop it. I really don't get how I'm gonna get the bearings though (maybe it wont use any)

Now I better start reading a book to understand the plans... someday...

EDIT: WAAAIT... we can buy used things of this kind... it's used legos that he doesn't know how to get through...
:)

The JGRO plans are pretty straight forward. There are a couple of places where you need to improvise a little, but as has been pointed out, there are a number of pictures around here showing what people have done. And if you get stuck, you can always ask for close-ups of different places.

I only recently finished my machine...okay, it isn't done yet. I need to put the rest of the lead screw bearings in (they were....delayed).

You will probably find plenty of folks happy to answer any questions you may run up against.

eternauta3k,

Just a few spatterings... If you need help with cutting any boards, I'd suggest that you just ask some of your locals. If you don't know any local woodworkers, then go find some. You gotta BE BOLD IN LIFE. Worst case you take your dad to your local HD and ask around a little. Go hang out in the wood department and loiter around till some old fart comes around and ask him if he knows any local woodworkers that would be willing to help a young person with a woodworking project. He's old, he's been around long enough to know some woodworkers.

Go with metric if you'd like. Just remember that if you change the length of any part that you need to adjust the length of all related parts.

The only book learning you need is to know how to read and how to create 3-view drawings. That's all you really need to be familiar with.

As for bearings, you should have no problem getting the ones that are used in the inline skates. Lots of us use these.

Rance

That's an inspiration! :D
School's ending in a few weeks, so I'll have plenty of time for the project. I've learnt a bit from this site (kinds of threads, bearings, linear guides, etc.) and I'm starting to get the JGRO plans, by seeing how each page references a part described somewhere else, and so on.
Wee I'm so happy :)

I forget the URL, but it's attached to the plans page somewhere. If I can find it then you can.

He made some modifications in his generation 2 machine that are not in the plans. Things like the use of press fit oil impregnated bronze bushings mcmaster.com (http://mcmaster.com) instead of using the skate bearings, use of drill rod http://wttool.com instead of black gas pipe, 1" steel tube supports to the table, and things like that. The generation 2 machine looks a lot more stable and easier to set up.

If you don't have a shop class then I'm assuming that you attend a private school (the Catholic school I taught at for a year didn't have shop either). Check with you local public school and see if they have an adult ed course in woodworking. A drill press, table saw, and band saw would greatly help you make the thing. Check your local universities. Most large universities have a wood/metal shop to support their physics department. Most shops like that have professional machinists, and they often are allowed to take outside jobs (I still get all my welding done at the University I did my grad work at).

Most of all, read everything you can get your hands on. Think carefully and talk to a lot of people about what you want to do and how you want the machine to proform.

Remember, most of what you use is reusable (motors, boards, etc.). If your first machine isn't perfect, pull the parts and make a better one (better yet, sell it on ebay for $1.00 and $1000.00 shipping :) , there is another thread about this ebay thing).

I think if I had to summarise things in 6 words or less I would say; talk, read, think, and take it slow.

Steven

Here we go, the JGRO home page (It's in his contact info with the router plans). He is a bussy man, please respect that, and post you questions here instead of bothering him at home as he requests in his contact info.

http://www.nconnect.net/~jgro/

So happy!
Exams are ending next Wednesday and I think I know where I'll buy most things (an Easy not so far away).
I can get skate bearings on mercadolibre or deremate, the local equivalents of ebay, and pretty much everything else needed for the JGRO machine is standard. The tools you said I needed are available at my dad's, so I can start building soon. He allocated a room for me to do aeromodelism (they don't like me to use the dining room at home), photography (it's a darkroom) and now this. :)
It appears there won't be any trouble with imperial parts,so most problems solved. So far it doesn't seem like an expensive machine. I know a place to get surplus servos, and I'm making the driver board myself.
I guess I'll use the linuxcnc software, since it's free, it's linux and I'm cheap :P

Been a while... here's an update:
I already started shopping for parts for the accurate machine. I have some time until they arrive, so this morning I thought about how simple JGRO seemed and decided to build it (not much support from my dad but he's not the most rational person at that time of the day :P )
I'll check nearby woodshops for fibrofacil and hardware stores for bolts and threaded rod... and that's pretty much it. I'll figure out the delrin later.

:banana:

(not much support from my dad but he's not the most rational person at that time of the day :P )

Hey, go easy on the old guy, some of us are probably the same age as your dad and just as cranky or irrational in the morning :)

Yay, found a place that sells & cuts wood to size 4 blocks away! Will threaded rod, rather than acme/ground, be fine?
It'd be awesome to machine aluminum (even if it's slowly) with this.

The threaded rod will work. I prefer ACME because I think they thread it better (the typical threaded rod I see in the local hardware stores just feels crappy and I have to chase the threads with a die to make sure they are clean. I would strongly recomend larger rod like 1/2in (12mm). You will get less whip. Also, ACME is 10 pitch and typical hardware store rod is 13. Using acme your machine will move faster at lower motor speeds (all the torque curves I have seen for motors says the torque falls off as the speed increases. Lower speeds = higher torque). I have even seen people recomending acme 2 start or 4 start rod (which would effectively give you about 4 or 6 pitch).

Steven

Probably not the correct place to ask, but what's 2 start or 4 start acme?

Thanks

OK, you know on a normal screw, the way there's *1* thread that twists its way up the screw? On a 2-start, there are 2 threads side-by-side. 4-start has 4 sets of threads.

-- Chuck Knight

Thanks. Guess I'll order the cuts today & buy threaded rod, alu. angles, etc. Any tips on getting delrin?

Edit: found a couple of sellers:

3M
Industrias JQ (www.jq.com.ar)


Edit2: :banana: :banana: I actually called the people at JQ! The dimensions I gave were a bit messed up (I didn't take into account that there are three nuts & three tensioners) but they said it'd be around 5 dollars. I guess the correct size would be under $10
:banana:

for Delrin there is also McMaster-Carr (http://mcmaster.com). I have found them to be very good, and they ship internationally. I got mine off of ebay though. So you might want to look there too. The two big sellers of delrin on ebay are an american and a britt (I don't remember names). I don't know if you will run into import duties from brittian being a former colony (I don't know if that gives you some special economic status... it doesn't do it for us here. Finding a local supplier or local machine shop would be good too. The pieces you need can often be found in the discard bins of larger shops or sellers. In cases where you only need a small amount begging often works well (that's how I got the chips for my driver boards).

If you check out Joes 2006 machine on this site he embedded actual steel nuts into UHMWPE (cheep plastic cutting board material available at most stores) to make his antibacklash nuts. This will cause more wear on the leadscrew (keeping it greased will help). But using a standard threaded rod or something else easily available then there is no problem with replacing them every few years (depending on how many hours a day you plan to run the router). You cound probably embed them in wood too.

Also check out Joes double rail system (don't know if I mentioned that to you before).

Steven

Thanks for the help. I think that for something this price, it'd be better to buy locally. I'll take into account the discards part.
By the way, we were a Spanish colony. Just the Falkland islands were conquered by the English who-knows-when (not too proud of my history knowledge)
<nationalism>In the continent, we repelled them twice</nationalism> :D (flame2)

Sorry about that, for some reason I thought you were as Australian then I was originally answering you. Then I checked out the link for jq and realized my mistake.

So yopur not a big history fan, hows your knowlege of football (soccer)? Was there a D'Antonio who was once (or still may be) a high official in football (president of the national football association or something like that)?

Nope, not too keen on football either :)
I liked joe's double pipe system but it's.... complicated. I know it isn't too difficult to make but if I start modifying pieces, I have to make sure it fits together. Maybe the next machine :D

Update on parts: I'll definitely remember to buy them tomorrow :withstupi

Then do what Joe did. Make the first machine. Meanwhile ask Joe for a copy of the plans. He will send them to you or give you a link you can download them from.

Use the first machine to cut the parts for the second machine. Then the second machine will fit together perfectly.

Pull your servo's and everything rom the first machine and install them on the second.

Then you have the perfect, very ridgid machine.

Once you have the first machine built, building the second just involves about 3 sheets of MDF or plywood, glue, and a few fairly inexpensive parts (like lead screws and antibacklash nuts, and even those can be canibalized from the first machine).

Steven

Nice! What set me back from doing Joe's was that the interlocking ribs seem hard to cut precisely (which is important because it isn't adjustable).
I might end up with 2 roller/pipe MDF machines and 1 aluminum THK slide machine :)

With the interlocking ribs, what I am doing is making up one rib very carefully and then using the router table (old fashion non-cnc table) to reproduce that rib the necessary number of times.

BTW, the guy I mentioned before who was the comissioner of the national football league... he is my cousin.