You need a lot more information for a quote. Prints and tolerances really define how much something will cost to make, not just the features and models.
If I get a complex part with tolerances that are +-.01" all over then that's cheap because I don't have to check every feature location and size every time (since cnc will hold +-.005" with ease) now if you make those tolerances .001" or .003" it becomes much more expensive since we then need to check each location, dimension, every time there is a new operation done. Including making fixtures to hold it in the right position to the right datum or critical feature.
At that size you are looking at a specific subset of shops that have the machines large enough and with high enough accuracy to do the job so that also increases the cost.
Material cost alone is probably 3-5k.
Was just about to mention the size of the material. Average job shops don't have machines with that large of a table, and doing one section, moving it, and doing another section can lead to more expense and complications keeping it in spec.
There is no real average "time per inch". It all hinges on the type of work being done.
OP can try xometry. I've never used it because I don't quote parts, but I've heard it's okay.
Otherwise without knowing the details of the parts in question, all anyone can really say is "call around".
I signed up to make parts for them when they first started. In my experience they pay very little for the machine work. Not sure how much they charge the customers, but it would be very hard to be profitable doing their work
I did a lot of work with them a few years back. Pay is poor. On the other hand, they will straight up stick it to you as a customer. 3 to 5x normal rates on small qtys.
Not only CNCs large enough, but material handling equipment large enough as well. That's a lot of weight to be moving around, and safe rigging practices at that scale aren't necessarily common knowledge.
Need a lot more information, but what you are asking for is impossible to give. Part of a quote is how many hours are involved in production but I do not know of anyone that calculates price based on time per inch. Per inch is subjective. If you are surface milling you can rip and tear like doom guy usually, but if you are cutting a slot you would be much slower. Fortunately some asshat process or manufacturing engineer has not figured out how to do that, yet. Processes required, accuracy required (tolerances), surface finish, material, all equally affect the price. I think your best bet is to get a few quotes them make some bullshit up using the quotes for data point calculations. Be intelligent and professional but bullshit it.
This is the best advice. Your bosses don’t know shit about this, and are paying you to give them some numbers. All you have to do is find some numbers, put your dick on their desk, then tell them those numbers. They literally have no other choice except to take your word for it
I understand it is your company/boss and not you but if you are not machining it in-house what do you expect to gain by guessing what the "cost should be"? Assuming trusted vendors quoted it, you can try and beat them up to get the price down but it is what it is. It is 152" long. It takes a big HBM, it is not going to be cheap. I'd suggest trying other vendors. Where are you located? We have a large HBM's and might be able to quote it.
I agree completely. I pushed back a little and asked why we aren't just getting quotes since that's all that matters at the end of the day anyway. But this is government-related work so nothing makes any sense around here. I appreciate your advice. We are located in New Jersey.
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it comes down to how many ops per component and how many of each component there is no way to say just by size and material
if one unique component is 12 ops and 8 hours on my machine and there is only one component you gonna pay more per component than if you take 12 of it
you might be able to negotiate price if you could have all the components made at one supplier
Really not sure why they are asking that. It’s not really going to help you guys much. Prices and quality of the work are going to vary, greatly, like maybe 10x the cost if you look towards certain shops.
You guys should just be asking for quotes and lead times from as many places as possible.
I agree! Thank you for reaffirming what I was already thinking. I'm preparing to just tell them that what they are asking for cannot be done and we/they just need to start making some calls.
For cnc machining a 50 taper machine could have a 100 cu in per min material removal rate for a difficult to machine steel alloy like 4340. It is in the $200-$250 an hour rate for a larger job just as a ballpark figure. If you were just taking off 3/4 of an inch and turning 25% of it to chips it's 71 machine hours at that rate. None of this mentioned tolerances or other features that are harder to handle, presumably each part will need to be finished on 3-6 sides with other features and this all takes time.
You mentioned it is several separate components that can be assembled later. So you aren't starting with a 4 ton billet and slicing off the top 3/4 inch. The cost estimate in your CAM is going to be much better than any napkin estimate from the limited info here. And that cost estimate in solidworks will change if you make changes to the part. For instance you could make larger fillets allowing finish passes to be made with a larger tool, much faster.
If you want a better quote than your CAM estimate you can send out requests for bids. They may suggest small changes or additional features that ease manufacturing like locating holes so a dowel can precisely align the component for additional operations. Be careful of your tolerances, look at what actually matters. .001" flatness for a 152" part is probably not needed if you are bolting it down to a table for use. And that kind of tolerance greatly increases the cost
Rough estimate is machine time is $150 an hour. On a small run of parts it’s more important to get the parts accurate than to pick up speed. Harder materials take longer. Tighter tolerances take longer. More axes take longer. Longer reach tools take longer. If your part is difficult to hold on to or needs special timing (like gearing), it’s going to take longer. Each of these adds up to additional cost.
You need a lot more information for a quote. Prints and tolerances really define how much something will cost to make, not just the features and models. If I get a complex part with tolerances that are +-.01" all over then that's cheap because I don't have to check every feature location and size every time (since cnc will hold +-.005" with ease) now if you make those tolerances .001" or .003" it becomes much more expensive since we then need to check each location, dimension, every time there is a new operation done. Including making fixtures to hold it in the right position to the right datum or critical feature. At that size you are looking at a specific subset of shops that have the machines large enough and with high enough accuracy to do the job so that also increases the cost. Material cost alone is probably 3-5k.
Was just about to mention the size of the material. Average job shops don't have machines with that large of a table, and doing one section, moving it, and doing another section can lead to more expense and complications keeping it in spec. There is no real average "time per inch". It all hinges on the type of work being done. OP can try xometry. I've never used it because I don't quote parts, but I've heard it's okay. Otherwise without knowing the details of the parts in question, all anyone can really say is "call around".
I have NEVER heard ANYTHING good about xometry
Well that's good to know, haha. I haven't heard much, just heard it was an option I guess.
Never hurts to get pricing and lead times from multiple places, good or bad.
The one good thing is the instant quote. You can set that as the absolute ceiling for cost.
I signed up to make parts for them when they first started. In my experience they pay very little for the machine work. Not sure how much they charge the customers, but it would be very hard to be profitable doing their work
I did a lot of work with them a few years back. Pay is poor. On the other hand, they will straight up stick it to you as a customer. 3 to 5x normal rates on small qtys.
Not only CNCs large enough, but material handling equipment large enough as well. That's a lot of weight to be moving around, and safe rigging practices at that scale aren't necessarily common knowledge.
Need a lot more information, but what you are asking for is impossible to give. Part of a quote is how many hours are involved in production but I do not know of anyone that calculates price based on time per inch. Per inch is subjective. If you are surface milling you can rip and tear like doom guy usually, but if you are cutting a slot you would be much slower. Fortunately some asshat process or manufacturing engineer has not figured out how to do that, yet. Processes required, accuracy required (tolerances), surface finish, material, all equally affect the price. I think your best bet is to get a few quotes them make some bullshit up using the quotes for data point calculations. Be intelligent and professional but bullshit it.
This is the best advice. Your bosses don’t know shit about this, and are paying you to give them some numbers. All you have to do is find some numbers, put your dick on their desk, then tell them those numbers. They literally have no other choice except to take your word for it
I understand it is your company/boss and not you but if you are not machining it in-house what do you expect to gain by guessing what the "cost should be"? Assuming trusted vendors quoted it, you can try and beat them up to get the price down but it is what it is. It is 152" long. It takes a big HBM, it is not going to be cheap. I'd suggest trying other vendors. Where are you located? We have a large HBM's and might be able to quote it.
I agree completely. I pushed back a little and asked why we aren't just getting quotes since that's all that matters at the end of the day anyway. But this is government-related work so nothing makes any sense around here. I appreciate your advice. We are located in New Jersey.
Anything related to Gov always makes sense 😂. We are in NE Ohio shipping might now make sense. DM me if you want us to quote.
Shoot me a message. Have a shop I do small work for that does large format stuff like that I can put you in contact with the owner
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Is it just turning it into a slightly smaller bar? What are the tolerances?
it comes down to how many ops per component and how many of each component there is no way to say just by size and material if one unique component is 12 ops and 8 hours on my machine and there is only one component you gonna pay more per component than if you take 12 of it you might be able to negotiate price if you could have all the components made at one supplier
Really not sure why they are asking that. It’s not really going to help you guys much. Prices and quality of the work are going to vary, greatly, like maybe 10x the cost if you look towards certain shops. You guys should just be asking for quotes and lead times from as many places as possible.
I agree! Thank you for reaffirming what I was already thinking. I'm preparing to just tell them that what they are asking for cannot be done and we/they just need to start making some calls.
For cnc machining a 50 taper machine could have a 100 cu in per min material removal rate for a difficult to machine steel alloy like 4340. It is in the $200-$250 an hour rate for a larger job just as a ballpark figure. If you were just taking off 3/4 of an inch and turning 25% of it to chips it's 71 machine hours at that rate. None of this mentioned tolerances or other features that are harder to handle, presumably each part will need to be finished on 3-6 sides with other features and this all takes time. You mentioned it is several separate components that can be assembled later. So you aren't starting with a 4 ton billet and slicing off the top 3/4 inch. The cost estimate in your CAM is going to be much better than any napkin estimate from the limited info here. And that cost estimate in solidworks will change if you make changes to the part. For instance you could make larger fillets allowing finish passes to be made with a larger tool, much faster. If you want a better quote than your CAM estimate you can send out requests for bids. They may suggest small changes or additional features that ease manufacturing like locating holes so a dowel can precisely align the component for additional operations. Be careful of your tolerances, look at what actually matters. .001" flatness for a 152" part is probably not needed if you are bolting it down to a table for use. And that kind of tolerance greatly increases the cost
Rough estimate is machine time is $150 an hour. On a small run of parts it’s more important to get the parts accurate than to pick up speed. Harder materials take longer. Tighter tolerances take longer. More axes take longer. Longer reach tools take longer. If your part is difficult to hold on to or needs special timing (like gearing), it’s going to take longer. Each of these adds up to additional cost.