Have no idea what I'm doing, but want to learn!

[mmcmdl]

To preface: I have absolutely NO idea what I'm doing when it comes to machining. Nothing. I have never even seen a machine shop. I have no idea about terminology, technique, or proper practices.

Welcome . You're in the right place as we have no clue as to what we are doing also .

As far as your parts , that's a simple part to machine but a dimensioned print would be needed .

 

[brino]

Wow, some of those drawings I've seen are hugely complicated! This is way outside what I originally thought it would be.......I was sort of (naively) thinking I could just walk into some shop where a bunch of guys were just standing around, and talk them into doing it on the cheap.

@Scootered it sounds like you're starting to understand the size of the divide between where you started and the machinists that are asking for detailed drawings.

I have a forstner bit in the garage, and it says 1/2" on the side of it. The holes it cuts measure out to be a half-inch in diameter, whether I'm drilling into old pine from a pallet, or a piece of hard maple. If its more than a 1/2" hole, say 9/16" then it isn't a half-inch hole, is it?

@ttabbal is right on with this:

Regarding your drill bit... It does not make a 0.5" hole. It makes a hole that is close to the right size. All drill bits do. You don't have the tools to measure it, but it's still there. Perhaps you don't care about the difference, but a machinist does. There are no perfect parts or features. The very best machinist or even CNC machines will have some error. It might be extremely small, but it's there. Thus, we have tolerances.

In fact, even if your drill bit is exactly 0.5000000 inch diameter, your hole will be bigger due to run-out (non-concentricity) of the drill chuck, and un-even sharpening of the bit. The hole might not be perfectly straight as the bit can wander with hard spots in the material. The hole might also be out of round.

Machinists are accustomed to working in thousandths of an inch. They have been trained to care about it, and therefore want to know tolerences with any part they are asked to build.

Another component of all this is the material. The 1/2" hole you drill in any wood will change with realtive humidity, but you'd need special equipment to measure it. For most things built in wood this is either too small to care about, or accounted for with slots, like where table tops are connected to aprons with a joint that allows for movement, or panels in a frame for a cabinet door have extra room to expand.

So for projects in wood it makes no sense to try to work to a thousandths of an inch....it would measure different tomorrow.

-brino

 

[stupoty]

the nature of the project isn't relevant, nor is the final purpose for the metal parts relevant

lol come on, now we really need to know

The "V" slots could be milled with a regular end mill with the milling head set at an angle, If you made a long bar with all the "V" slots in you could then cut the blanks for the parts from it.

Holes could be drilled on a mill or drill press. As other have said the exact method may depend upon your required tolerance, for example , do the holes have to be round ? if yes you may wish to ream them after drilling which will provide an accurately sized and round hole.

The curve on the back of two of them could be milled simply with a "ball end" end mill of the correct diameter.

bish bash bosh , done. (well maybe a little swaring and curse words when you cant find the correct tooling in the workshop or need to purchase another random item you don't have on hand or all your mesuremnts were wrong.)





Stu

 

[ThinWoodsman]

Let me play around in Paint Shop Pro and see what I can come up with based on the lessons I've already learned here.

Graph paper or whiteboard. Then take a picture.

 

[mmcmdl]

Graph paper or whiteboard. Then take a picture.

Worked in a model / R&D shop for years with engineers . They had ideas but not a clue as how to put them into a finished product . Sketches on napkins etc and verbal instructions were the norm . Sometimes simple is better .

 

[HBilly1022]

Maybe I'm missing something but if you created the sketch, all you have to do, is dimension it with the software that was used to create it. You had to input dimensions to create the drawing. That is the same information someone would require to create the part. Does your software have a dimensions feature? If not then provide a list of the information you used to create the sketch.

1. length of part - already provided.
2. width - already provided.
3. angle, depth and spacing of grooves
4. diameter of holes and location from the ends
5. the parts appear to have different overall thicknesses. What are they?
6. the arch in the underside of the one part needs to be dimensioned. How deep and what radius? To see the effect for yourself, go back to your drawing and input 0.5" radius and then a 2" radius and see the change.

The information needed to create the part has already been input by you, in order to create the sketch. All you need to do now provide the same information to the person that will make it.

And the last thing ....... noted by you and the very friendly people on this forum is......... tolerances! I think you stated that tolerance to be 1/16". Is that for the diameter of the holes and all of the linear measurements?

Machinists and woodworkers are used to working with very different tolerances and to make sure you get what you need / want, that is a critical question that needs to be answered. You set the tolerances and they can be anything you want. Just to exaggerate the point, you could state the tolerances to be within 1" +/- or you could state they must be within 0.0005" +/-. They are both achievable but at very different costs.

I hope this helps you understand. I'm kind of a matter of fact person and I'm trying to help but sometimes my written word doesn't convey that intention.

 

[Wheelcock]

As I mentioned in my original post, it's a piece of flat metal bar that's 3-1/2" long by 1 wide, by 3/8" thick. I set the "depth" of that radius in the body of the bar to be one-half the thickness, or 3/16" just like the drawing shows, or would if it were dimensioned.

I put the piece of pipe in to show how it would be welded to the part. And in a way, you're right, because it does show what the overall finished thing would look like, if it were sawed in half, crosswise.

I mean this as friendly advice, not to discourage you:

Sounds like you have a limited budget and limited access to tools. A good first step might be to step back and really think about what features you absolutely must have to make the finished article work for your intended use, and what you can accomplish with off-the-shelf materials and simple tools.

Do you have to use bar stock? Sounds like with your current plan, you could use u channel and weld to your pipe: this eliminates the need to machine the backside radius on one of your pieces. Don't have access to a welder? Maybe you can use square tube instead of round pipe and work on a surface of the tube directly. Do your grooves have to be perfectly parallel 90deg Vs? If they are just meant to provide grip, maybe you can use a cutting disk on an angle grinder, or a burr on a Dremel, or a hacksaw and files. If your tolerances are loose enough, perhaps you can drill your holes with a decent bit and powered hand drill. Since I don't really know what you are trying to accomplish, and what resources and experience are available to you I'm taking shots in the dark... Your intended purpose is relevant to someone interested in helping you so that they can understand what is important to the success of your project and share their experience accordingly -- you have come to a place where there are many who are more than happy to share experiences and think through your project with you!

Tying into what others have said, your design represents the culmination of your efforts to think through the best way to achieve your desired outcome given the resources available (time, money, tooling, experience), and the blueprint is your best effort to communicate your design. When you provide a blueprint to someone else to produce the article, you are providing them with an unambiguous representation of what is to be produced that takes into account manufacturing methods, referencing for measurement, and tolerancing. In most cases, this is what a professional machinist will expect, but is overkill for something with wide open tolerances you knock out in an hour or two in the garage -- it all depends on what you really need at the end of the day

 

[MarkM]

Sorry but I thought you wanted to learn! Not just have your part made. Someone mentioned Tolerances, I mentioned to maybe tale a look at a drawing of a simple shaft which was to make a light go off to see how simple a drawing can be and to see how and what the views represent. How dimensions are applied to a drawing.
If you want to learn throw away your computer and grab a pencil and a pc. of paper and draw something to represent your part. Your Second drawing will be better and we are willing to help you. Sorry but to me it seems you are stuck on getting your part made and don t want to apply yourself to learn. What is Tolerance? How do you place a feature on a drawing?
I pointed it out as well as others. Info needed. Think of a ten foot diameter pipe. The radius is five feet. I go and cut a radius for a Five inch shaft at a depth of 3/16. Now how is that five foot radius going to conform and be able to be welded. An extreme for sure. Something to think about. Put the info on a print rather than have us go through every post. One drawing with all your info. You represent the kind of customers machinist run from. Ya were all going to be sitting around to discuss your part and do it on the cheap. How much an hr. Do you think that would cost the company and would you be willing to pay that or do you expect the company to take the hit.
Good luck!

 

[mmcmdl]

I was sort of (naively) thinking I could just walk into some shop where a bunch of guys were just standing around, and talk them into doing it on the cheap.

You'll never see that . We'll all be sitting around in comfy chairs !

Ooops, I gave something away!

Mmmmm..........................top secret , need to know basis .

( just pulling your chain )

 

[bhigdog]

At the risk of appearing a grumpy old man I get the distinct impression the OP would rather talk than do. Everyone here has given many versions of help and suggestions and the response is usually a "yeah but", "gee that's complicated", "I don't know how".
When I was a kid we made what we needed and improvised as required. Scooters were made from a length of 2 X 4, the wheels from an old roller skate, a wooden crate, and all held together with whatever we could find in the old man's garage. No one said "gee that's too hard". We learned by doing and we didn't have the internet with it's unlimited knowledge at our finger tips.
Every question that been asked of us has the answers readily available. Every process required can be duplicated with simple tools and devices found in the most basic home shop. Every attempt at making the parts will advance ones knowledge and skill base far more than asking about it.
I'd be far more interested helping someone who actually tried and was unsuccessful than one who just wanted tell me why he can't even try.

I think I have a great deal to learn

Yes you do......................Bob