emachineshop

Hello

I have a complicated project requiring CNC maching. Emachineshop looks like an option, but low volume parts are very expensive...So I want to know what I may be getting into before I drop the dough.

Does anyone have experience with emachineshop that they would like to share? I am interested in Quality, timeliness, precision, etc. and anything else you can think of.

FYI I am looking at getting the attached parts machined. (Pay no attention to the dimensions on the drawings as some of them are wrong.)

Ok, I may be the only one here who can speak to their service - and even at that it's only based on two experiences with them.

My nutshell:
- They'll be slower than they estimate.
- You have to spell out EVERYTHING important, take nothing for granted.
- If you're doing something with tight tolerances (like a diode press-fit, or even lens threading) make heavy use of "comments to machinist" to basically say:

"Over-ride default tolerances. This measurement MUST BE BETWEEN 5.62 and 5.68mm in diameter."
or
"This tap MUST smoothly thread an M12x0.5 threaded brass part. I can send you an example of such part if needed."
etc

I'll give you another tip. The quantity discounts scale VERY fast, especially with small parts. To order 10 of something is often only 50% more than ordering 1 of it. And ordering 100 of something is often only 50% more than ordering 10. In other words, why spend $300 on 1 one part, when you could spend $500 on 100 parts? If it's a cool enough part, sell the extras. It's the only way to get your price down.

That said, if you really only want 1, and if you have a good schematic drawn up, go to CNCZone.com and post it. See what a machinist will quote you for 1x copy. They'll probably be cheaper for 1x than ordering 1x through emachineshop. However, the machinists on CNCZone.com tend to be less competitive once you get up into multiple parts.

Thanks this is exactly what I wanted to know. I figured lots of people here would have used them unless there was a reason. I am mainly concerned with the threading and DP diode as you mentioned. Were your results acceptable after all the comements to machinist? How was the direct press?

The economics of this work out such that I will be ordering at least 3 of the complicated parts and 21 of the simple parts.

Jubathoph said:

Thanks this is exactly what I wanted to know. I figured lots of people here would have used them unless there was a reason. I am mainly concerned with the threading and DP diode as you mentioned. Were your results acceptable after all the comements to machinist? How was the direct press?

The economics of this work out such that I will be ordering at least 3 of the complicated parts and 21 of the simple parts.

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I found that with my orders, especially the most recent one which was a 3.8mm diode pocket, I had to quality-control every part on my end after receipt. I ended up tossing 30% of the modules.

Of those 30%, a bunch of them were probably actually fine, but I just didn't feel they were perfect enough to sell. In my case, I'm bitching about 0.05mm of tolerance that they were off by. I ended up testing them all with a caliper on my end - annoying, but in my experience with EMS, worth doing.

I should have commented to the machinist MORE with added emphasis in my wording. But all in all, I'm still really happy with EMS. I mean, their software is easy to use, and they're affordable. They're slow, but if you're not in a rush, they're good.

The one final comment I'd have, is that EMS isn't "one shop". They're a company that contracts your work out to a machinist. So it's possible, in fact, it's highly likely, that my two orders from them have been made in completely different shops, potentially half way around the world from each other.

Jubathoph said:

Hello

I have a complicated project requiring CNC maching. Emachineshop looks like an option, but low volume parts are very expensive...So I want to know what I may be getting into before I drop the dough.

Does anyone have experience with emachineshop that they would like to share? I am interested in Quality, timeliness, precision, etc. and anything else you can think of.

FYI I am looking at getting the attached parts machined. (Pay no attention to the dimensions on the drawings as some of them are wrong.)

Click to expand...

I work at eMachineShop - thanks for looking at our website, and for considering using us for you machined parts. I'd be glad to help you and other forum users with any questions you have about using us.

The parts in your .pdf files are straightforward and are certainly within our capability. I think you'd find they are very easy to draw in our software.

As another poster pointed out, quantity is certainly a factor in the cost of any CNC machines part. With a low quantity run of relatively simple parts like these, the actual time the machine cuts metal is a small percentage of the cost of the job. The programming and machine setup time are a much larger percentage of the total. As the quantity of parts increase, that setup time is spread over a larger number of pieces, and the cost of extra parts becomes relatively small in comparison to just making a few of them. Some of the other factors that drive the cost are the material used, the tightness of the tolerances that need to be held, the complexity of the part and how quickly the parts need to be produced. Our website has several areas where we give tips on things you can do to minimize cost, and these would apply to any machine shop you deal with. If you are not a machinist, some of the factors may not be obvious, especially in the area of parts design and tolerancing. I'd be glad to answer any questions you have on your design as you go forward.

rhd said:

Ok, I may be the only one here who can speak to their service - and even at that it's only based on two experiences with them.

My nutshell:
- They'll be slower than they estimate.
- You have to spell out EVERYTHING important, take nothing for granted.
- If you're doing something with tight tolerances (like a diode press-fit, or even lens threading) make heavy use of "comments to machinist" to basically say:

"Over-ride default tolerances. This measurement MUST BE BETWEEN 5.62 and 5.68mm in diameter."
or
"This tap MUST smoothly thread an M12x0.5 threaded brass part. I can send you an example of such part if needed."
etc

I'll give you another tip. The quantity discounts scale VERY fast, especially with small parts. To order 10 of something is often only 50% more than ordering 1 of it. And ordering 100 of something is often only 50% more than ordering 10. In other words, why spend $300 on 1 one part, when you could spend $500 on 100 parts? If it's a cool enough part, sell the extras. It's the only way to get your price down.

That said, if you really only want 1, and if you have a good schematic drawn up, go to CNCZone.com and post it. See what a machinist will quote you for 1x copy. They'll probably be cheaper for 1x than ordering 1x through emachineshop. However, the machinists on CNCZone.com tend to be less competitive once you get up into multiple parts.

Click to expand...

Thanks for sharing your experiences with using us! I think you captured the basic economics of buying qty 1 vs qty 100 very well. We have lots of customers who do just what you suggest - come up with a good design for their own use, manufacture enough parts to sell some to others, and lower their own cost. In some cases, their cost went below $0, and they made money on their parts. We have several customers who have bootstrapped their way into new careers, launched from their good ideas, and using as as their manufacturer as they scaled up. With today's CNC machines and services like ours your only limits are your own creativity and entrepreneurial spirit.

You comments about tolerances and using Comments to Machinist are also spot on. No machinist "knows" what you want your parts to look like - the only way to communicate this is through the drawings used to make the parts. Never assume that the machinist knows what you want - be explicit. Our software tries to simplify the process, and help you set your specifications, but ultimately only you know what you need. The software also gives expert advice on your design, and warns of potential manufacturing issues. Just one nit to pick - a comment to the machinist like "must thread smoothly" is a subjective term. You'd be better researching thread fit specifications, if this is an important item, and use a thread fit specification. The same thing applies to things that a non-machinist may think of as subjective, like surface finish. In the machinist's language, these all have an objective, measurable specification associated with them.

rhd said:

I found that with my orders, especially the most recent one which was a 3.8mm diode pocket, I had to quality-control every part on my end after receipt. I ended up tossing 30% of the modules.

Of those 30%, a bunch of them were probably actually fine, but I just didn't feel they were perfect enough to sell. In my case, I'm bitching about 0.05mm of tolerance that they were off by. I ended up testing them all with a caliper on my end - annoying, but in my experience with EMS, worth doing.

I should have commented to the machinist MORE with added emphasis in my wording. But all in all, I'm still really happy with EMS. I mean, their software is easy to use, and they're affordable. They're slow, but if you're not in a rush, they're good.

The one final comment I'd have, is that EMS isn't "one shop". They're a company that contracts your work out to a machinist. So it's possible, in fact, it's highly likely, that my two orders from them have been made in completely different shops, potentially half way around the world from each other.

Click to expand...

Just a few comments on the points in this post. First, and most important, thanks again for using us in the past, and I'm very glad your experiences were positive ones!

If you receive parts that are out of tolerance to the specs you specify, please let us know, and we will correct or remake them. We do have an extensive QC process, including using a CMM, and we want to have your parts right. Again, if a spec is tight and important, please be sure that this is specified in your drawing.

As to the actual manufacturing of your parts, you are only partially correct. We do have a rather sizeable manufacturing facility here, and we do CNC milling, CNC turning and CNC waterjet cutting in house. We do also use partner suppliers to manufacture some parts for our customers. This hybrid approach allows us to offer customers a wide range of tolerance, delivery time and price options. The bottom line is whoever makes the part, we strive to deliver it in the timeframe, to the quality standard and at the price requested by the customer.

Thanks for considering us, Jubathoph, and thanks for using us, rhd! Please don't hesitate to ask any other questions, and I'll do my best to give you a quick and accurate answer.

Gary

eMachineShop.com

gary nj said:

You comments about tolerances and using Comments to Machinist are also spot on. No machinist "knows" what you want your parts to look like - the only way to communicate this is through the drawings used to make the parts. Never assume that the machinist knows what you want - be explicit. Our software tries to simplify the process, and help you set your specifications, but ultimately only you know what you need. The software also gives expert advice on your design, and warns of potential manufacturing issues. Just one nit to pick - a comment to the machinist like "must thread smoothly" is a subjective term. You'd be better researching thread fit specifications, if this is an important item, and use a thread fit specification. The same thing applies to things that a non-machinist may think of as subjective, like surface finish. In the machinist's language, these all have an objective, measurable specification associated with them.

Click to expand...

Hey Gary, nice to meet you!

One of the things your software really should add, is the ability to set a tolerance for each individual measurement (if needed). That would be a net benefit across the board. People wouldn't set blanket "too-tight" tolerances that didn't apply to certain measurements, but where it actually counted, they could make sure the parts were as-required.

One of the very frustrating aspects of the current "comments to machinist" approach, is that a written comment can't really get factored in to the pricing equation. For small runs of small pieces, a LOT of the decision to even go forward with a project depends on pricing. It's nice to know what that pricing will actually be, before you commit say 5 hours to get a design perfect, as opposed to just an initial 1 hour to get it to the point of being price-analyzable.

I've never understood why there was no per measurement tolerance setting

Oh - the other thing. I've often found that the VR cost listed for the metals in your materials list doesn't behave the way you would expect it to in terms of influencing price. The conclusion that I have drawn is that sometimes a lower VR cost material is harder to work, so the price is actually higher if you choose it instead of a more expensive, but easier to work with material. It would be nice if this multiplicative step was factored into an additional column that basically gave a bottom line of material expense (considering material value, and additional costs of manufacturing with it).

Thanks for the additional comments. The pricing model is already very complex in what it models and considers. We do try and make it more accurate and automated, but it's always a balance between keeping it manageable in terms of size and performance, and giving our customers as many options as possible in terms of what they can request. The individual measurements tolerance is something that would be very difficult to implement, because some drawings have many, many points of measurement - considering them individually would be very hard to do. Your point about the relative costs of different materials vs the impact that the materials have on the machining cost is true, but the model does take both factors into account in coming up with a final price.

We want to always give our customers the chance to manufacture parts just the way they want, so I'm guessing manual quoting via Comments to Machinists will be part of our business model in the foreseeable future. That said, we do always want to make it more responsive to our customers, and I'll make sure your comments get in front of the folks that make these decisions. Thanks again for taking the time to share your thoughts - we appreciate it! :thanks:

Hey, I never even heard of you until I came here. Now I know you exist and are at least worth trying! Thanks RHD!

ts

im going to submit a few designs and see if they can beat the local detroit shops.
No one can beat direct china shops but the MOQ is sometimes high for proto work.

Gary I appreciate your response and input here. Are you on the forum strictly to represent eMachineShop or because you are interested in lasers or both? I would like to send you my latest design for comments on machinability and clarity before pulling the trigger. Feel free to PM me your email.

Jubathoph said:

design for comments on machinability

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Did you think to reduce a number of screws? 3 instead of 4.
Could you use imperial sizes (#2-56 UNC)? It could be easy/cheaper to find in your local hardware shop.

Thanks lazeristas

I need maximum heat transfer from the diode mount to the lens mount which is acting as my heat sink in conjunction with the rest of the host so I used 4 screws to allow for more pressure/better contact area. Also, 4 screws are easier to allign with eachother; you will notice that they are all arranged in a "grid" which will be easier to machine and quality check.

As far as the thread, I was able to find the M2x0.4 at the fastenal for $.09 each

Jubathoph said:

Gary I appreciate your response and input here. Are you on the forum strictly to represent eMachineShop or because you are interested in lasers or both? I would like to send you my latest design for comments on machinability and clarity before pulling the trigger. Feel free to PM me your email.

Click to expand...

Hi - sorry for the delay in responding to your post - I was away for a few days. I am here because of the discussion that included eMachine Shop's services. I am an active net forum participant - if you are discussing racing radio control cars That said, I'm always interested in machining and how people with a passion for a particular subject use machining. You can email me at garykosits at emachineshop dot com

rhd said:

Hey Gary, nice to meet you!

One of the things your software really should add, is the ability to set a tolerance for each individual measurement (if needed). That would be a net benefit across the board. People wouldn't set blanket "too-tight" tolerances that didn't apply to certain measurements, but where it actually counted, they could make sure the parts were as-required.

One of the very frustrating aspects of the current "comments to machinist" approach, is that a written comment can't really get factored in to the pricing equation. For small runs of small pieces, a LOT of the decision to even go forward with a project depends on pricing. It's nice to know what that pricing will actually be, before you commit say 5 hours to get a design perfect, as opposed to just an initial 1 hour to get it to the point of being price-analyzable.

I've never understood why there was no per measurement tolerance setting

Oh - the other thing. I've often found that the VR cost listed for the metals in your materials list doesn't behave the way you would expect it to in terms of influencing price. The conclusion that I have drawn is that sometimes a lower VR cost material is harder to work, so the price is actually higher if you choose it instead of a more expensive, but easier to work with material. It would be nice if this multiplicative step was factored into an additional column that basically gave a bottom line of material expense (considering material value, and additional costs of manufacturing with it).

Click to expand...

RHD - I mentioned your suggestion about individual dimension tolerancing to the powers that be, and guess what I found out -- that feature is already in the software! You can draw a straight line, and then while that line is selected, go to Line | Machine | Tolerance on the drop down menus. You can set an individual tolerance for that line that overrides the global tolerance you specified in Settings, and that individual tolerance is priced. You specify the tolerance of the diameter of a circle this same way by drawing a straight line across the diameter and setting the tolerance of that straight line. Apparently this feature was added a release or two back, which may be why you weren't aware of it if you first started using the software before that. Hope this is helpful to you! Gary

tsteele93 said:

Hey, I never even heard of you until I came here. Now I know you exist and are at least worth trying! Thanks RHD!

ts

Click to expand...

kiyoukan said:

im going to submit a few designs and see if they can beat the local detroit shops.
No one can beat direct china shops but the MOQ is sometimes high for proto work.

Click to expand...

Thanks for giving us a look! Let me know if you have any additional questions. Gary

gary nj said:

Hi - sorry for the delay in responding to your post - I was away for a few days. I am here because of the discussion that included eMachine Shop's services. I am an active net forum participant - if you are discussing racing radio control cars That said, I'm always interested in machining and how people with a passion for a particular subject use machining. You can email me at garykosits at emachineshop dot com

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Thanks Gary. I used to mess with RC Cars as well. Had 1/8 Nitro buggy and on-road cars, very addicting and even more expensive than lasers!! Hard to believe but those things can go 0-60 faster than a Ferrari...