[cncoperator]

Would you happen to know how much material would need to be held inside the chuck in order to machine this part, or are there specs somewhere that tell you this? I'm wondering how much waste I would have when turning each one.

There are never ending machining strategies. If speed and thread concentricity to the other features took a back seat to conserving material you could cut threads in the first op and then screw the part into a fixture and do all the other turning ops which would result in minimal material waste

[rdsi]

It has little or nothing to do with the CAM. It would require CCW-turning (i.e. - "left-handed") tools.

Yep, you're right about that ...

Another thought was using some air pressure and adding some dowel pins in the threaded holes to better align things. Something like this could be held to perform the top ops then rotate 90 degrees to drill the two little holes.

[kstrauss]

You could use blanks long enough for two parts, thread both ends and then saw/part the threaded pieces into two parts for the next operation. That approach would probably eliminate any wasted stock for clamping.

[motoeng]

You could use blanks long enough for two parts, thread both ends and then saw/part the threaded pieces into two parts for the next operation. That approach would probably eliminate any wasted stock for clamping.

Not quite sure I follow how this would work.? Are you saying you would turn the entire outer profile (threads included) but stop just short of cutting it off, then flip the blank in the chuck, and turn the other end? That doesn't seem like it would work since the chuck wouldn't have very good contact area with the newly turned end, so I must not be understanding correctly.

[keen]

Hi Motoeng.

This is such a classic dilemma! One thing I would chip in is that us cautious engineers are attracted to small steps towards the end goal. We don't like risk and we want flexibility. But when it comes to machinery that approach often costs more time and money in the long run.

If you can see where the likely end goal is, try and take two steps at a time. For example if it is Rapidturn then Slant pro - can you go straight to Slant pro. Or if it is Tormach then Haas...can you go straight to Haas.

Try and work out your end goal - and then map back from there.

All the best - Cliff

[GLCarlson]

Hi Motoeng.

This is such a classic dilemma! One thing I would chip in is that us cautious engineers are attracted to small steps towards the end goal. We don't like risk and we want flexibility. But when it comes to machinery that approach often costs more time and money in the long run.

If you can see where the likely end goal is, try and take two steps at a time. For example if it is Rapidturn then Slant pro - can you go straight to Slant pro. Or if it is Tormach then Haas...can you go straight to Haas.

Try and work out your end goal - and then map back from there.

All the best - Cliff

VERY good advice. Really. I've made that mistake, professionally and personally, on hardware. And lived with the consequences.

An implicit assumption in there is that all of the steps have similar -probably low- risk. That is, you're pretty sure to certain that Rapidturn WILL work; and similarly, Slant Pro WILL work and is a better longterm answer. Skip the first step for sure. Incremental approaches are usually more costly, but worthwhile when one of the steps is high risk. When each step is very likely to work, skip steps; you'll save time, money, and skull sweat. And get to profit faster.

I hate to give Stephen Covey credit for anything, but when buying big iron, start with the end in mind.

[motoeng]

Skip the first step for sure.

I hear ya. The problem is the $$ difference between steps 1 and 2. We're talking a price difference of roughly 7X between Slant Pro vs RT, and 2X between the 1100 and Haas Mini mill. So we go from 20K to 40K+ in a hurry.

I understand the reasoning - why spend 20K on machines/tooling when there's a good chance they'll sit idle and never be used again once you upgrade. Adding insult to injury is that your tools won't be interchangeable, etc.

The old saying "you gotta start somewhere" comes to mind.

Lots of excellent info in this thread guys - it is greatly appreciated.

[GLCarlson]

I hear ya. The problem is the $$ difference ...

A very valid point. And part of the risk profile. Waiting adds risk. Spending more adds risk. And absolute dollar amounts -the difference between 20K and 40- are a lot more sobering than "twice the price".

Personally, I justify all this by saying that some guys buy boats, some guys buy heavy iron. Sure, it's a rationalization. So far, it works.

One must, indeed, start. I have an old RF30 that I swear I'm going to melt into window sash weights; it takes up room, is apparently worthless, yet it got me a so-called milling machine 20 years before I could afford a Tormach (and also about 20 years before the 1100 launched!). Fortunately, I didn't have room for a Bridgeport at the time. Or the ability to even get it into the shop had there been room. Barely inadequate Chinese iron was the option.

Sometimes you take the least bad choice.

[kstrauss]

Not quite sure I follow how this would work.? Are you saying you would turn the entire outer profile (threads included) but stop just short of cutting it off, then flip the blank in the chuck, and turn the other end? That doesn't seem like it would work since the chuck wouldn't have very good contact area with the newly turned end, so I must not be understanding correctly.

I was unclear.

Turn or mill + thread mill the end with the threads including the shoulder adjacent to the threads. Flip end-for-end and repeat for the other end. This will give pieces with threads on both ends and the middle section completely un-machined. Slice in the middle of each piece. Screw the resultant pieces into a fixture so that the not yet machined ends are up and mill as a batch. You'll need a slightly fancy fixture that locks the screwed part in place to prevent unscrewing or use LH cutters as Ray suggested. I'm assuming that having the two ends concentric is also a +/-0.005 tolerance.

If thread milling gives an adequate surface finish your could do everything on the mill and have very little wasted stock and by doing in batches greatly reduce the number of tool changes.

[Jim Dawson]

I'm in kind of the same situation. I built a bunch of parts on a manual lathe and my CNC mill. But the production need is projected to increase in the next couple of months. The CNC mill is adequate, but manually turning/milling the parts is much too slow for the anticipated volume, be doing batches of 50 to 100 parts. So I found a used CNC lathe with live tooling, $11,000. Going to combine the lathe and mill work on those parts into one operation. Should save about 20 min per part. In addition to the time savings on turning the other related parts. Even at that, I expect the CNC lathe to sit idle most of the time.Sometime ya just gotta take a chance.

[brian257]

Don't forget about the option of getting your turned blanks from another shop and then buying a Tormach to finish the milling parts of it. Not sure how much you would save getting the parts with just the turning done vs. having them completely done, but might be worth looking into. That option might be particularly appealing if the different designs you want to be able to make can all start with the same turned blank. You will also then have a machine that you can use to completely make your prototypes, short run production, custom engraving on your parts, fixtures, personal stuff you want that have nothing to do with your business and whatever else you need even if it doesn't work out as your main production machine. If nothing else, you will learn a lot and have a machine that could be resold if you decide you don't need it. Find a good deal on a used machine and your risk is very little.

[SCzEngrgGroup]

One other option to consider: Go to mfg.com, create a (free) account, and post an RFQ for your parts. Within a few days, you'll have quotes from shops all around the world. I've done this several times, and come up with some really good vendors that I've used for years. In several cases, they made the parts. plated them and shipped them to my door for less it would have cost me to buy the raw materials, even though the quantities were rather small. It costs nothing to try, and you might get lucky, like I did. You'll usually get a few completely outrageous quotes, but there's almost always one gem buried in the responses.

Regards,
Ray L.

[motoeng]

One other option to consider: Go to mfg.com

That's actually how I found my current supplier. I could probably cut their cost by 1/3 if not more by going overseas, but I gave that a try in the past and the quality was just too hit or miss. I'd rather pay more and know what I'm going to get.

[GITERDUN]

Just guessing on the actual size, but from my experience you could probably get 500 of them done in china for around 4-5.00 each. Figure 20% defect rate which is common for them, that brings the price to 5-6.00 each. So you could get your 500 units for about 2500-3000 total. If you make decent money at that cost, why take a chance on spending 20K and your own labor to do it yourself.

[motoeng]

Just guessing on the actual size, but from my experience you could probably get 500 of them done in china for around 4-5.00 each. Figure 20% defect rate which is common for them, that brings the price to 5-6.00 each. So you could get your 500 units for about 2500-3000 total. If you make decent money at that cost, why take a chance on spending 20K and your own labor to do it yourself.

When I first started out in 2012, I had this part made in China for $2.50. Price has since gone up due to increased labor costs over there. I think I went through 4 suppliers before saying the heck with it and bringing manufacturing into the US.

The first three suppliers had poor quality from the get-go, maybe 50% usable rate if I was lucky. One time I received 500 pieces that wouldn't even thread 1/4 of the way into the go gage. How do you get it that wrong??

On the 4th supplier I finally thought I had found the ONE. Great quality, decent price. After about 1500-2000 parts their quality went to crap, almost as if they were outsourcing the job to someone else or something. It was a night and day difference, so strange.

Anyway - I'm perfectly happy with my supplier right now, but as stated before, it would be nice to have some flexibility in the manufacturing dept to test new products and do small runs of existing products to hold me over between larger orders. I'm notoriously bad at reordering parts when I'm running low, and often end up running out and missing out on sales - shame on me.

One day, I would like to make all of my parts myself, but I think that will have to wait until my retirement years, which are several decades away.

[GITERDUN]

When I first started out in 2012, I had this part made in China for $2.50. Price has since gone up due to increased labor costs over there. I think I went through 4 suppliers before saying the heck with it and bringing manufacturing into the US.

The first three suppliers had poor quality from the get-go, maybe 50% usable rate if I was lucky. One time I received 500 pieces that wouldn't even thread 1/4 of the way into the go gage. How do you get it that wrong??

On the 4th supplier I finally thought I had found the ONE. Great quality, decent price. After about 1500-2000 parts their quality went to crap, almost as if they were outsourcing the job to someone else or something. It was a night and day difference, so strange.

Anyway - I'm perfectly happy with my supplier right now, but as stated before, it would be nice to have some flexibility in the manufacturing dept to test new products and do small runs of existing products to hold me over between larger orders. I'm notoriously bad at reordering parts when I'm running low, and often end up running out and missing out on sales - shame on me.

One day, I would like to make all of my parts myself, but I think that will have to wait until my retirement years, which are several decades away.

Yeah- that sounds like the standard Chinese practice- they will usually do the first order at or below cost to lock you in, then on subsequent orders they farm out as much as possible to the cheapest bidder to make a big profit. Historically China cyclically grows to prosperity and then eventually collapses due to corruption and nepotism. Since you have already been down that road, your only task now is to decide on which machine to buy and take control of your own production.
Good luck.

[Tkamsker]

Hi ,
I think that Tormach can do it as much as other machines
I think you need an CNC Lathe which is able to CNC thread cut.
So the steps would be cnc lathe the part with the thread
Then put it on the Mill in an 4th axis which i would set horizontal.
Do an Mounting part to screw the Thread in the 4th axis
Then you mill it
While you mill you can run the next Lathe part.

You then get everything but missing the hex hole.
Wich you can do by hand at the lathe with an breaching tool.
I foyu do 500 pieces or less i think you need 2 machines,
And ATC would help you at the mill i would see it as necessaryity

[Steve Seebold]

If you're wanting to stay in the $2,50 range then the Tormach is definitely not the machine for you.

If you try to run this part on a Tormach, I think you're going to be looking more in the $10.00 to $12.00 range.

Don't forget, those shops in China are using 20 and 30 horsepower machines and your Tormach has a rip snortin 1.5.

In the 6 plus years I have had my 1100 I have learned some cool tricks to enhance metal removal rates.

I've been machining for close to 60 years and I consider myself to be a pretty good at what I do, but there is no way I could make that part for even $8.00 and make money on it. Not on a Tormach.

[motoeng]

If you're wanting to stay in the $2,50 range then the Tormach is definitely not the machine for you.

That's what I paid when first venturing into this business. I pay more than that now through my US supplier.

Steve when you say you couldn't make this for less than $8/piece, is it simply due to the lower speeds at which the Tormach runs and thus the greater amount of your time that is required to get to a finished part? I would think operator time is a much larger factor than the cost of actually running the machine, especially one as small as the Tormach.

[Steve Seebold]

That's what I paid when first venturing into this business. I pay more than that now through my US supplier.

Steve when you say you couldn't make this for less than $8/piece, is it simply due to the lower speeds at which the Tormach runs and thus the greater amount of your time that is required to get to a finished part? I would think operator time is a much larger factor than the cost of actually running the machine, especially one as small as the Tormach.

Yes. I wouldn't even attempt that part in production on a Tormach. If your shop rate is $60.00 per hour, I seriously doubt you could make more than 5 or 6 parts per hour on a Tormach. That's 50 to 60 pieces per day "IF" you don't have any interruptions or distractions like salesmen stopping by to sell you some crap you've never heard of or your friends stop by just to talk and distract you.

If I were going to run that part, I would build 4 fixtures that held 6 parts each and have one fixture in the machine running, one fixture on the bench loading and 2 fixtures as back ups.

I would make my fixtures out of 7075 aluminum and use Mitee Bite clamps to hold the parts in the fixtures.