I think most machinist want a cnc but for good reason and myth they are scared

WOW, I take too long to compose my responses.

Alot was posted between reading and posting my response.

I personaly feel that with software and CNC's someone (meaning ME) can do better work because the the software
figures feeds and speed that I don't know or am too lazy to look up. So I prefer a CNC

By having a CNC I can do much more with it than I could with a manual machine.

One is not better than the other in my opinion.

You are only limited by your imagination no matter which one you have.

I think the biggest fear would be the learnng curve. If you have no experience reading or writing G code it would be a challenge.

Then there is the initial cost. If you are tech savey you could convert a manual to cnc.

I have no experience with the cost or installation of a retrofit but it could be done I'm sure with some technical skills. I
wouldn't be afraid of it but would not want the pain of having to fool with it.

I fix them for a living. I'm afraid my retrofit would be like the mechanic's old jalopy project.

Those are my fears

Itt
 
There seems to be a general feeling that if a person can post on an internet web site, they are capable of converting a machine to CNC, setting up the programs and operating it. To me, that is like telling a person that because they know how to drive a car, they are able to design, build and drive a race car. The person is a car user. I am a computer user. The qualifications beyond that point are quite similar.

Bill
 
Bill,

It's really not that bad. Working the control stuff is pretty basic and not that hard to deal with unless you really want to roll up your sleeves and get into it. The programs that take the model and convert it to steps for the machine to take are pretty straight forward as well unless you want to tweak things. You just tell it what kind of tool you have in the machine and push the button and go. Most have pre-set information like cutting speeds and cut depths for different materials built in.

The bigger learning curve is designing the model for the part. Most is pretty cumbersome because they really aren't designed to create the parts manually. They have programming tools built in to automate the creation of parts by filling out some specifications rather than manually drawing them out. The fancy name is parametric modeling. You go into some drafting program like Autocad or Pro-E or some such, and it becomes fill in the blanks for differences in standard parts for a particular job. An architect doesn't go in and draw each stair part. They tell it to to make stairs that go from here to here. They also have a lot of stuff in to optimize production like nesting, where you can tell it to fit as many as you can on a piece of material "This big."

For simple jobs, many people program it directly. The commands are really simple. Go to point A. Move the tool down this high and move to point B. Pick up the tool. Move in a circle with such and such radius. Move between points A B and C and then move the cutter X amount and repeat 10 times. That kind of stuff. Basically just like a recipe. Of course this can get tedious for really complex parts.

You can also just use parts that other people create. Many manufacturers give out cad models of parts that they sell for designers to use in creating their own stuff. As an example, you can go over to 80/20 inc. that makes Aluminum extrusions and they have the design files for their products. That way you can make a model and use theirs to create parts that work with it. There are also sites like Thingiverse and SketchUp 3D Warehouse where people contribute their models for others to share.

There is a learning curve but it is not as steep as you might think. It is kind of like using a word processor where it has a gazillion functions available but you can do 95% of what you want it just by knowing some of them.
 
I have a very strong manual background and tried my best to avoid CNC machines for several reasons....mostly because cnc wasn't in my vocational school til the last 3 months of my senior year and the instructors had no idea what they were doing because they were manual machinists. After watching these 2 instructors fumble through a demo or two, I figured there was no way I would ever understand or be able to program. I avoided CNC at all cost. After finally breaking down and taking a few classes at our local community college, I found CNC to be a lot of fun. Its starting to take over any relaxing down time with trying to teach myself Bobcad/Bobart/Predator editor/Predator Virtual cnc...

I have some manual home shop machines ie..rf45 type manual mill and a 12x36 gear head gap bed manual lathe. I would love to convert them over to cnc but because I spent all these years avoiding CNC I have no idea how to convert these machines. I read the posts on this site and a couple others and I understand every cocncept of why each step was done. When it comes to all the electronics though...completely lost and have no idea what to buy and how to hook it up properly and get the whole shabang running to the best of its ability.

Stuff like this make me wish someone would just right the detailed instructional book on it and I could go from there. With my luck I would buy everything hook it up and while testing it it'll fly out of my garage creating a huge whole in the wall , land in the middle of the street, blow sky high and euthenize a neighbors pet...

So, I agree with everyone on this post and have my own reasons why I haven't converted.

Maybe someday I can do it...but as of now...I'll say it, I am scared to try and convert without completely destroying machines that work...
 
jumps4 said:
these are my reasons and my opinion
I was scared i was going to waste money i really didnt have on a machine that would be below standard and to complicated to learn.
so i started researching and found these problems for home cnc
1. there is no standard for the terms used by the manufactures of parts, the writers of software and just about every aspect of the building of your own cnc. I'm a auto mechanic and could not imagine a spark plug being called something else because another company made it. so for me to read most any literature on cnc i needed a list of terms and definitions to figure out each sentence. and that list is for just that manufacture. thats a lot of lists
2. ok it's killing our economy but without the chinese only the fortune 500 companies can do this and that brings us to translation. this guy in china reads chinese well but does not understand how the sentence translates into a readable english or any language for that matter to form a sentence so lets just pic an english word and put it down. no matter how you read it "cintered canine and crushed paste of yellow zest" is not a "hotdog with mustard"
3. wiring. just about anyone mechanical can modify the machine and do a good job , make it accurate with low cost ballscrews because cnc compensates for backlash automaticly when set up properly. the fact is wiring a cnc is as easy as playing with batterys , lightbulbs and switches like you probably did as a kid. here is the catch anyone can connect wire a to terminal b as per the instructions. nope the breakout board instructions say connect a wire from step+ on the breakout board to step+ on the motor controller. what is the controller i have a driver and it does not have the word step on it anywhere. it says pulse. your thinking magic smoke. the fact is the driver is the controller and step and pulse mean the same thing. so wiring now is a nightmare for the same reason as item 1. terms and standards.
4 learning the cad and cam programs and their cost. you are not nasa you need a cad software that draws circles squares rectangles ect where you want, then the size you want them, and saves in a dxf format. thats free online everywhere i use emachine shop it is so simple you draw the box and up at the top you say the box is here in x and y and it is this high and that wide thats it. drop a circle on the end delete the unneeded lines an you have a bullet. cam software same thing you want simple and low to no cost. are you really needing a software that cuts 5 axis in full blown 3d i cant even think 5 axis yet.
i have a bunch of free programs all limited but when you have them all you can do almost everything.
unless you want to just make scrap you wont write complete programs to finish a complex part in unending steps you very quickly pick the cut from the drawing and tell it the cutter size left right or on center, depth per pass and total depth. run it. thats good pick the next pocket corner and
continue. It is faster than reading prints mounting rotory tables and turning cranks and it dont get tired. It's working, your on the lathe making something else.
just my opinion and i guess you can tell i like cnc or anything i can make behave with my pc
if i could just mount steppers on my wife what a life this would be.
What Do You Think
steve
Click to expand...


Ah ... Do I have the right steppers?
Steppers depending on your wife's age , " Red 6 inch high heel steppers & a big bunch of flowers " works well for cooperation in almost any room in the house so long as the kids are miles away , all phones etc. are switched off & no once can see in through the windows.
 
No, I really don't. :pondering:

I prefer to do it the way I did it in the past (old guy I guess, 64). Its what I'm used to and it suits me. :noidea: I can see the advantages of CNC but don't need it for what I do.

I could use a good Quill DRO though just for repeat cuts on my mill. That would be handy. :ideas:
 
CNC shouldn't be scary as some have mentioned, but it can be very intimidating, especially when things don't go the way you want them to. And the first thing that comes to everyone's mind is "WRECK". If I program it wrong, I'm going to wreck it. And I've been there. The last 15 years that I was working before going on disability, I ran ProtoTraks, and they were programmed in "Conversational" mode. It took about a week to learn that, and a few more weeks to learn some tips and tricks. After going on disability, I knew that I would need something to do around the house to prevent boredom, and since I have ran machines almost all of my life, I bought a mill and a lathe.....both standard, not CNC. Last year I ran aross a B.P. Series 1 CNC. It had been 15+ years since I have programmed using G & M codes. But after reading some of the manuals, slowly things were coming back. It's a personal thing, but I like to program by hand, just to keep the gray matter in the old noggin' sharpened up a little.

But don't be afraid of CNC, or get "intimidated" by CNC. Once you learn the programming basics of CNC, it opens up a whole new world, especially for the home machinist. It saves a lot of time, but it allows you to machine some pretty cool stuff that you normally can't with standard equipment. Machining a half of a ball that is accurate in size is great, although you may have to do a little sanding. And it helps to hone your computer skills, it helps to hone your design skills, and so on. A three axis CNC takes an idea from inside your mind to an actual 3 dimensional part. Something that you can't normally do on standard equipment. And if you have a CAD program that will operate with your CNC, that is just an added bonus.

As far as being scared of CNC, or intimidated by CNC, there is not one person on here that ever regretted learning to run CNC, and not one person on here that has not wrecked a CNC either. It happens, and I've been there on a few occasions myself. The worst part of it is the big red button disappears when the endmill starts to bury itself somewhere that it is not supposed to go. LOL!!!!! But if you have a chance to learn CNC, to get a good deal and buy a CNC, and think that you may possibly like the idea of having one.......then GO FOR IT!!!!. Don't be afraid, don't be intimidated, and lower the table before you hit the "GO" button. LOL!!! One you go to CNC, you'll always go with a CNC every chance you get. It opens up all sorts of avenues to travel down.
 
Keven45: All of us that have run a CNC for more than a very short time have crashed one. I did it yesterday. Our programmer made a small change in a program and I uploaded it without out checking it since i was a 115 minute run and just a small change he made. My fault, I should have baby sited it all the way through. On wrong number or decimal point in a 10,000 line program and it's all she wrote. So I always run a new program with the rapids turned down to 25%

Clearly CNC isn't for everyone. I run CNC's all day at work, and have a Bridgeport manual mill at home. I do transmission mods on parts that are irreplaceable and one slip on the manual and I've got a very upset customer.

I just picked up a pretty large knee mill that had an outdated control on it and Jim Dawson and I (mostly Jim) are going to put an updated control on it. What takes me almost four hours on my manual will take about 1 hour on a CNC. I just picked up a volume customer for my mods and he said he'd bring me 10 to 20 housings at a time to modify. Well after working four or five 10 hour days at my regular job it's going to take me weeks do do that many on my manual. So for me CNC is the answer if I'm going to grow my small business. I had a CNC job shop years ago and built it from one manual mill to four CNC's. I did it once and I can do it again. I'm older now, more experience, but not necessarily smarter though.

I'd say assess your needs, if a CNC will save you time and get you where you want then go for it. If your smart enough to make chips with a manual then you probably have what it takes to go CNC. It just depends on how much you want it if you will be successful at it.
 
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+1 what both Kevin45 and Alloy said:)
 
I just finished converting my lathe to CNC, which is working great, and I am presently in the process of converting my mill to 4 axis CNC. I can not justify going to CNC, as alloy has, because I do not make any production parts as I am a Hobby Machinist and only make custom parts and specialty tools for my Automotive Repair business. I have always had a profound interest in electronics, programing and machines so combining the three make for a lot of learning and fun. Converting to CNC has taught me a lot and increased my machining skills. I also gained a lot more confidence in fabricating complex parts. Bob
 
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