Shop Floor Talk  

Go Back   Shop Floor Talk > Welding and Metalworking Forums > Machining

SFT Search:   
Reply
 
Thread Tools Display Modes
  #1  
Old 03-02-2019, 10:14 AM
Scootered Scootered is offline
Junior Member
 
Join Date: Feb 2019
Location: Eastern Central Georgia
Posts: 19
Default Project discussion - newbie with zero knowledge.

And that probably puts a target on my back. Please be gentle!

If this is the wrong place for this thread, please let me know and I'll move it, or ask for it to be moved, or delete it and start over in the proper location.

First, let me preface this by saying I have zero knowledge of metalworking. None. I have never even seen a machine shop, and I have no idea what all those tools and machines do. I don't know the proper terminology, or the right way to describe things. That is the very reason I came here.

I recently went to another machinist forum, and read a few posts to try to get an idea, only to see a thread where all these professional machinists utterly destroyed a newbie for asking a simple question. They did it in a hateful, hurtful, and rather sadistic manner, and appeared to openly enjoy it. I don't think that's the attitude here, after reading several threads. But please, remember that there was a time when you knew nothing, and be patient with me. Thanks!

I would like to learn how to adequately and properly describe two small metal pieces I would like to eventually have made. First and foremost, I'm not Warren Buffett, and would prefer not to sell my firstborn or mortgage my house to have this done. In other words, I'd like to eventually get it done for a fair price, on the cheap, as embarrassing as it is to say that.

Before I describe the pieces I'm talking about, let me try to describe where I'm coming from. I have some moderate woodworking background, and the level I'm at is, if someone came and said, I have this piece of wood, and I need a 5/16" hole in it where that pencil mark is, I'd pull out a 5/16" drill bit, and drill the hole where the pencil mark is. I can hear the gasps of horror already, over the lack of rocket-parts precision. On some of the forums where I've tried to read posts about metal working, I keep seeing all these zeros. For example, precision levels that could only be determined with the use of a microscope. I don't need that. It isn't necessary. Really.

I have in mind, these two pieces of flat steel bar. (yes, I know there are hundreds, if not thousands of alloys, but again, I don't have the specific knowledge to be able to name one) They should be inexpensive, readily-available, regular plain old steel. They are both 3-1/2" long, 1" wide, and have grooves on one side that run the long way. They also both have a pair of 1/2" holes in them. One of them is flat on the other side of the grooves, and is 1/4" thick. The other is 3/8" thick, and has a rounded groove on the other side of the longitudinal grooves. I have attached a very rough sketch of these pieces, so everyone can see clearly what I'm talking about.

Could I please start a discussion on how to describe these pieces in a way that they not only make sense to a machinist, but are correctly and properly detailed so that someone could make them if they chose to? That would, ultimately, be the goal. Finding someone to make them for me!

Thanks!!
Attached Thumbnails
Click image for larger version

Name:	parts-sketch-01.jpg
Views:	98
Size:	127.5 KB
ID:	149649  
Reply With Quote
  #2  
Old 03-02-2019, 10:30 AM
Scotts's Avatar
Scotts Scotts is offline
Stuff, Just stuff
 
Join Date: Dec 2004
Location: Wichita Kansas
Posts: 5,057
Default

Well Scootered,

Welcome in and It looks like you are looking for a set of vise jaws from what I see of your picture. Or something close.

What did you make the drawings with.

Scott
Reply With Quote
  #3  
Old 03-02-2019, 12:53 PM
GWIZ's Avatar
GWIZ GWIZ is offline
SFT Historian
 
Join Date: Feb 2006
Location: USA
Posts: 6,677
Default

Say the face side has 60deg V grooves 1/16" deep (serration's) that are cut length wise.

if you don't do the math right you may end up with a half V at the top or bottom groove.
you need to designate angle of V, depth, start the point where?
some flat will be cheaper. not full pointed (sharp)
sharp point in the root, or what ?

On the back side that would be a radius cut the full length.

Make a dimensional drawing and anyone should be ok with that.
The issue is you must include tolerances and not just say whatever is ok, that is just like telling a machinist I'm going to F with you until it works and cost you money and your reputation.

Then what type of finish do you need, mild-steel has a tearing effect when cut and the finish does not always come out as expected.

"mild steel" would be the run of the mill steel, if you want to harden them then you need something else.
__________________
*
*
The factory of the future will have only two employees, a man and a dog. The man will be there to feed the dog. The dog will be there to keep the man from touching the equipment. ~Warren G. Bennis
Reply With Quote
  #4  
Old 03-02-2019, 12:54 PM
greywynd's Avatar
greywynd greywynd is offline
I can dig it
 
Join Date: Dec 2005
Location: Wainwright, Alberta
Posts: 4,510
Default

You’ve described and sketched it well. Is this something that you are looking for a set for yourself, or larger volumes to resell?

Are the ‘grooves’ a particular profile?

I can think of a few ways to make parts like in your picture, the methods would depend on whether I’m making a pair, or 200 pair of them.




Sent from my iPhone using ShopFloorTalk mobile app
Reply With Quote
  #5  
Old 03-02-2019, 01:29 PM
LKeithR's Avatar
LKeithR LKeithR is offline
Hey...wait...is there a prize?
 
Join Date: Aug 2011
Location: Langley, B.C.
Posts: 4,843
Default

If you've modeled the parts as shown in your picture then you should have a supporting drawing that shows dimensions and details--most machine shops would need nothing more in order to make them. You really don't need to "describe" the parts unless you want to tell people what they will be used for.

It is the "use" more than anything else that will determine what material should be used. If you can't disclose that information because you're making something "secret" then it's going to be a lot more difficult to get others to help you determine the best material for the job. In the end, though, it should be possible to figure out what you need.

I suspect the "other" forum" you were talking about was Practical Machinist. Don't give up on them. They can be a bit harsh at times but collectively there is an absolutely huge pool of knowledge just waiting for you to tap into it. Some of the smartest professional machinists in the world hang out there.

If you want to visit PM--and you definitely should pose your questions over there--read and understand the rules and stick to them when posting. Most of the "newbies" who get burned on PM either don't read the rules or don't abide by them. They'll also tend to come across some times with a little too much swagger in their tone. Give them as much detail as you can in your first post including pictures and a description of what you're looking for. Be as clear and precise as possible and, above all, be patient and you'll find that you you'll get a lot in return...
__________________
Keith

Measure twice and cut once...or...wait, was that the other way around?
Reply With Quote
  #6  
Old 03-02-2019, 02:43 PM
Norm W's Avatar
Norm W Norm W is offline
Elite Member
 
Join Date: May 2006
Location: Syracuse, NY
Posts: 2,716
Default

Your post said, "Project Discussion." The drawings were great but without knowing what they are for, limits discussion of types of steel, possible improvements in design and machining methods. More information, would mean more discussion, which would mean more information for you.
__________________
Make over, make do, or do without

Why do I have to press one for English when you're just gonna transfer me to someone I can't understand anyway?

Grant me the strength to accept the things I cannot change, the courage to change the things I can & the friends to post my bail when I finally snap!
Reply With Quote
  #7  
Old 03-02-2019, 02:57 PM
Shade Tree Welder's Avatar
Shade Tree Welder Shade Tree Welder is offline
Grumpy Bastard
 
Join Date: Jun 2004
Location: Kankakee County, IL
Posts: 19,077
Default

1. I moved it to machining. Makes more sense here.
2. Valid questions, don't think anyone is going to jump your shit here,
unless you do the complete opposite of what everyone says you should
do. Ask Timmy about that... LOL
3. How many sets are you looking at doing?
__________________
Shade

"Prepare to defend yourselves."
-- Sergeant Major Basil L. Plumley, Ia Drang Valley
Reply With Quote
  #8  
Old 03-02-2019, 03:45 PM
Scootered Scootered is offline
Junior Member
 
Join Date: Feb 2019
Location: Eastern Central Georgia
Posts: 19
Default

Quote:
Originally Posted by Scotts View Post
Well Scootered,

Welcome in and It looks like you are looking for a set of vise jaws from what I see of your picture. Or something close.

What did you make the drawings with.

Scott
I have a really old, obsolete version of Paint Shop Pro.

You're exceptionally perceptive, as they are in fact, something very much along the lines of vise jaws. Except, there's a bolt that's going to be running through those holes, so that the pieces can be tightened around another thing. So the practice is the same, but the object isn't.

Reply With Quote
  #9  
Old 03-02-2019, 03:53 PM
Lew Hartswick Lew Hartswick is offline
Elite Member
 
Join Date: May 2008
Location: Albuquerque NM
Posts: 3,612
Default

As Keith said the FIRST thing I'd look for is a dimensioned DRAWING WITH
tollerances. Of course the quanty is the next thing. :-)
Pictures are great to start the discussion though. :-)
...lew... (woodworking for 60+ years, metal only about 30) :-)
Reply With Quote
  #10  
Old 03-02-2019, 04:04 PM
Scootered Scootered is offline
Junior Member
 
Join Date: Feb 2019
Location: Eastern Central Georgia
Posts: 19
Default

Quote:
Originally Posted by GWIZ View Post
Say the face side has 60deg V grooves 1/16" deep (serration's) that are cut length wise.

if you don't do the math right you may end up with a half V at the top or bottom groove. you need to designate angle of V, depth, start the point where? some flat will be cheaper. not full pointed (sharp)
sharp point in the root, or what ?
Way too complicated. The way I drew them, I created a polyline at right angles, and extruded it. Then I cut off one edge and then mirrored the whole thing. And in the grand scheme of things, I really don't think it would matter whether there are "half points" or not. This is not rocket engine parts, and there is no need for NASA level precision.

Quote:

On the back side that would be a radius cut the full length.
Yes, it would. It is the place where the pipe this is going to be welded to will go. I'm attaching a cross-section drawing to show how the pipe fits up in it, and the red parts are the weld. And the sketch I attached originally, shows it running the entire length.

Quote:

Make a dimensional drawing and anyone should be ok with that.
The issue is you must include tolerances and not just say whatever is ok, that is just like telling a machinist I'm going to F with you until it works and cost you money and your reputation.
You're going to have to explain to me why you think "machinists think that way." I might only be in the 9th grade, but I've seen middle school kids more mature than those machinists. I don't believe that this ridiculous level of 53 decimal place precision is even close to being necessary.

I've made three sets of these things out of reclaimed pallet wood, and never used anything to measure other than a Stanley tape measure. I have a decent router, and a pretty old standing drill press, but that's as complicated as it got. And I even used old wood from a broken-down pallet. If my piece of wood is 10 inches long, and I need a hole in the middle of it, then I measure 5 inches from one end, and presto! There's the middle. If I want to be careful, I measure from the other end too. Yep, the pencil mark came out in the same place. That's the middle, pull out that drill bit that's 1/2" in diameter, and drill away.

What I don't understand is, how can I make these things out of wood, and have them be perfectly what I want, and now they suddenly have to have all this math, precision, and detail? I just don't get that. It doesn't have to be as difficult as this. A half-inch hole is a half-inch hole is a half-inch hole, and anyone thinking it needs to be 0.000000X precise is just making it far too unnecessarily complicated. That's just ego. If it's anything else, like say, 9/16" then it isn't a half-inch hole, is it?

Quote:
Then what type of finish do you need, mild-steel has a tearing effect when cut and the finish does not always come out as expected.

"mild steel" would be the run of the mill steel, if you want to harden them then you need something else.
I had no idea that this type of thing was even a thing. Doesn't a tool working on a piece of steel sort of just scrape bits away? I've seen machining on "How its' Made" and it doesn't look like it's that bad a finish. So how do you finish metal where it doesn't look "torn"? I use sandpaper on wood, but if my tools are sharp enough, they don't care whether they're cutting pine, poplar, or maple. I don't understand the properties of steel where it can look like it's "torn".

And you've said something else that doesn't make sense. How can you harden steel? It's already hard as steel!

Attached Thumbnails
Click image for larger version

Name:	tool-000001.png
Views:	25
Size:	21.6 KB
ID:	149656  

Last edited by Scootered; 03-02-2019 at 04:13 PM. Reason: add image
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Web Search:

All times are GMT -5. The time now is 03:43 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.