Thread: Need some lathe parts made (someone good)

I am looking for someone to machine a few hundred of these parts, maybe more if the price is right. They need to be made from 303 ss. I have attached two drawings and a picture. The picture is of the existing parts we are using. As you can see the threads are terrible and we are constantly having issues with them. I would like to get a quote for both parts. They are basically the same, the only difference is the taper below the sphere. One is a curved taper and the other is a linear taper. Also below the shaft of the part needs to be .08 8-32 threads, to screw the part into a base. The base of the part should work as the head of the screw.

Need to get these parts made ASAP. Please reply or pm me and I will contact quickly.

I understand the thread space is small, and I'm open to small adjustments as long as the overall function is the same.

Originally Posted by bravogifts

Hi,

PM sent, please check.

Sorry, forgot to ask what the tolerance is like?

Thanks for your time!

Hugo

He asked for somebody good !!....kinda leaves you out doesn't it???????

"One is a curved taper"

radius of curve?

That's a good question. I used a fillet in the design. I will look asap and get the radius size.

The threads do look terrible, looks like a chipped thread tool or too big of a nose radius for an 8-32. On the other hand, your will need to live with either a full thread one turn short of the shoulder (.031) a dwell of a thread tool, or a .031 thread relief, take your pick. I make parts like that all the time, If you can live with a two week delivery let me know by PM.

It's not metric, so it's not for military drones.

But it surely seems to be for an RC aircraft.

And you don't have to tell us.

Have you studied the Dubro catalog:

http://dubro.com/resources/catalogs/...by_Catalog.pdf

If it's not a stock item, how far from a catalog item is it?

I think its a pawn for chess

Its actually a part for some belt buckles we make. It allows you to fasten the buckle once you have tightened it. I understand that their will be little threads. I'm open to the easiest way possible for you guys to machine them, just need them to function properly.

would it be possible to make them out of 304
eliminate the thread, make it a "stem"
tig weld the part in place
although it can be welded, the last time I was involved with welding 303 the shielding gas was hydogen
(I always took my lunch break when the boss did the welding)

Here is how the part looks once installed.

MJK,

I don't know why you would want to machine them from 304, its harder to machine than 303. Maybe that's just me though, and they need to be threaded. This is a cosmetic part, don't need to add extra steps to the process.

I suggested 304 thinking the other component was also stainless, possible 304 or a weldable type

Originally Posted by mjk

I suggested 304 thinking the other component was also stainless, possible 304 or a weldable type

Don't take this personal, but why does everyone always try to redesign a part on here when someone wants a simple quote. If I tried that with Boeing or Gruman they'd laugh and get a new vendor.

Well thats a good question. There are a slew of answers,

They are either lazy
Think they are smarter
Don't have CAD/CAM so they want an easier way to machine it.
They don't have the material in stock.
They are looking for something to do because they are bored.
They are in a bidding war with another company trying to make parts for NASA, so they want to make it look like a space ship, so they can add it to their portfolio, and get that job

I'm always open to new ideas, especially if it makes the part more efficient or better, but honestly I understand because i'm a machinist and I see things my way, and alot of times I want to change peoples ideas cause I think mine are better. However, they write the checks, and I just smile

Originally Posted by D

Don't take this personal, but why does everyone always try to redesign a part on here when someone wants a simple quote. If I tried that with Boeing or Gruman they'd laugh and get a new vendor.

I think it is a healthy behavior, if not carried to extremes.

As far as stainless being needed for this product, I doubt its need. How many clothing belts have stainless steel components? It's going to end up coated with body oils, and it will be in constant motion. It's so damned close to the ball studs used by RC aircraft that it might be sourced from Dubro, or others, perhaps as a special, perhaps as a stock item, if the material wasn't so picky.

Let's say you have an ongoing relationship with some part, perhaps not this part. Customer orders, you buy the material, you make the part, customer picks up the part. The cycle repeats several times. The scrap is problematic due to its metallurgy, and the price and availability give some trouble but you have those troubles factored into the price.

Then the order stops, you call and attempt to learn what you can about any failure on your part and the answer is along the line of "this other shop wanted to do the part, they suggested ways to save me time and money, and it seemed they cared more about my part than you do".


Now what?

Well, Since your the expert, I was going to agree, but I'm going to have to disagree. Unless your wearing a belt while streaking or you sweat like godzilla, changes are you probably wont be covering a buckle in bodily fluids. I have ordered a few thousand of these parts in the past, and I can say we have tried all sorts of variations. I have been making buckles for nearly three years now. We sell to a large number of colleges, business, celebrities, etc. All of our buckles are machined from 303 or 304. They range from $100-$400, depending on how custom they get. There are a few reasons for making them from stainless.

1. The entire buckle is stainless, attaching an aluminum ball part is kinda pointless. Also doesn't look too good.
2. Since these are mainly for golfers (and some not so skinny guys) the part actually has to be strong cause there is a ton of force actually applied, that you don't realize.
3. Since the depth of the hole is .08-.1" deep, the threads on aluminum have failed to hold up in the past.
4. Quality is king to me, and I like the look and finish stainless, not to mention its slightly more durable. I write the checks, I am the boss ....thats why they are made the way they are.


The End

Originally Posted by Blackdiamond

Here is how the part looks once installed.

why don't you just machine the part .0015" to .002" press fit then there is no welding and you just have to use a reamer on the buckel part install tool is just a round tube that has about .003" play and 1 hit with hammer it is set.

"I understand the thread space is small, and I'm open to small adjustments as long as the overall function is the same"

"small adjustments" can be a variety of options depending on the tools at your disposal
if all you have is a turning center, then bidding on the part as pictured above may be your only option.

I've been making a part that involves 1-1/2 threads of a 10-32 18-8 stud engaged in a piece of 304 ss
Loctite was the original means of locking it in place, but there were a few that would fail.
By changing to a tig welded stud, part failure was eliminated, full confidence in the part was achieved
the welding takes about 10 seconds, polishing maybe a minute, its not for NASA, but it's important for the customer that the part performs and stays together.

In all honesty I don't care how people design their parts, but if I have a suggestion that MAY help them, I will pass it on.
I also learn from reading when people make suggestions, evan the crazy ones.

And there are big companies that welcome a suggestion for making a part another way, you just sometimes have to find the right ear to listen to you.

and answers to the above slew:
no,no,do have both,actually do,perpetually bored ADHD always have something to do,no...why I won't bid the threaded end would present a problem for me, someone with a Swiss as suggested by a fellow shop would be be better suited to knock these out, as shown

Mike

Hornby,

You bring up a great point. Once again, we have tried this. I have thought to myself the same thing many times. However, If you think about it, the part would essentially be the same, minus the threads. You then would have to create another fixture for either a press or vise. Then, you have to worry about marring the design that was machined on the front because in some cases, the buckle is only .135 thin. On top of all that, the hole is only around .1" deep max and we have had some guys (I don't know how) rip them out. Then putting in a replacement obviously doesn't work, because the hole is now too big. The threads make them easy to attach, in a shorter amount of time. If some idiot breaks one off, I just ship him a part, and he can replace it himself. Not to mention, adding threads didn't seem to add but a few seconds to each part.

Explaining my design is making me realize just how much R&D went into these parts over the years. My expertise is in CAD design. I have come up with about 94 revisions for this part, and it seems like the more complex we make it the more it fails. So essentially the mini trailer hitch ball works.

MJK,

I have ADD so I understand haha. I completely agree, the weld idea would be much stronger. We have experimented also with welding in the past, it produced a strong part, but we always had an orange or blue hue on the front of the buckle. That and it wasnt cosmeticly pleasing. I know you are all machinists, fabricators, etc. But think cosmetic. Would you go into nordstrom, or a high end store, and see something welded. These are more like pieces of jewelry. With all of that being said. I am just looking for some quotes for the parts as described. It would be nice to have a good person or shop to send some lathe work to. I design a ton of parts for people as well as my own company, but we do not do any turning. We only run vmc stuff. A great relationship would be good to establish, especially with someone or a shop that is up to date on the technology side. It's frustrating dealing with all the guys who cant open new solid parts, or they charge you out the a$$ because they don't have tool setters, probes, or anything to help speed up setup time. In my opinion, that's why people don't do prototyping. Its not that you cant make money, its because they don't want to setup parts. Well, spend some money and it doesn't take much time. (sorry for the rambling) Any way, just some thoughts so we all don't keep wasting our time with design ideas.

below are some pix for your refrence