Metric to american

Brento

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Has anyone done any project from books like these? My issue is all of the projects are in metric and id like to convert into american. I was curious if its easier to convert everything to american at known nominations or just make the part to the actual conversion from metric.

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That would depend largely on the complexity of the project and your design/engineering talents. That is, if you mean taking 10mm from print and subbing in 3/8"(0.375).

I'd probably convert the drawings to SAE/Imperial. Have done so for few commercial jobs. Just have to convert the tolerances too.
 
Never done any from the books--but it's pretty easy to convert metric to imperial (25.4mm=1"). Think that's what I would do.
 
Why not follow the rest of the wold and use metric then you can just follow the projects as is.
My lathe is imperial but all my projects are metric so its no real problem. and seriously, Americans actually do use the metric system and have done so for years, you just divide an inch into 1/10ths, 1/100s, 1/1000s instead of a millimeter.
I use both systems and would just transcribe the measurements to the system I wanted. If done exactly and not to the nearest equivalent there should be no problems.
 
There is alot of complex parts so the best thing is to maybe just convert to us to measure with my instruments but in the end keep dimensions the same.
 
I have been working with the metric system for more than 50 years building and modifying scale models. H-O trains....
The scale is 3.5mm to 1.0 foot. The end result is that I work as easily with the metric system as with imperial. Although imperial is what I grew up with, metric is somewhat easier. The important thing is to "get comfortable" with metric measurement. Most of my construction experience is with imperial. The machine work is maybe 30-70 metric.

A few years ago, I built an electric powered bicycle. The doner(?) was a late model Schwinn, made in China. So all the additions I made were done in metric. With few exceptions, such as I don't have metric keyway broaches. Had to finagle that. A three wheeler arrangement, it worked out well.

A few dimensions to get comforteble with:
25 mm is a fuzz less than an inch (25.4mm=1 inch)
1 mm is 0.03937 inch (roughly 40 thou)
10 mm X 1.5 thread is so close to 3/8-16 TPI you need to measure cose to find the difference.

With little expenditure, you can tool up for metric. A good metric caliper or micrometer along with the conversion factors for imperial leadscrews will yeild good metric measurements. On the other hand, conversion to imperial is just a matter of converting all the measurements, to the above listed factors. The bicycle mentioned was done in metric to make everything one system, no half and half, no two sets of wrenches, et al. My model building is done to imperial, because I must interact with others that have no grasp (nor want) of metric. Go for it, Dude. By whatever system is easiest for you.
Bill Hudson​
 
I have been working with the metric system for more than 50 years building and modifying scale models. H-O trains....
The scale is 3.5mm to 1.0 foot. The end result is that I work as easily with the metric system as with imperial. Although imperial is what I grew up with, metric is somewhat easier. The important thing is to "get comfortable" with metric measurement. Most of my construction experience is with imperial. The machine work is maybe 30-70 metric.

A few years ago, I built an electric powered bicycle. The doner(?) was a late model Schwinn, made in China. So all the additions I made were done in metric. With few exceptions, such as I don't have metric keyway broaches. Had to finagle that. A three wheeler arrangement, it worked out well.

A few dimensions to get comforteble with:
25 mm is a fuzz less than an inch (25.4mm=1 inch)
1 mm is 0.03937 inch (roughly 40 thou)
10 mm X 1.5 thread is so close to 3/8-16 TPI you need to measure cose to find the difference.

With little expenditure, you can tool up for metric. A good metric caliper or micrometer along with the conversion factors for imperial leadscrews will yeild good metric measurements. On the other hand, conversion to imperial is just a matter of converting all the measurements, to the above listed factors. The bicycle mentioned was done in metric to make everything one system, no half and half, no two sets of wrenches, et al. My model building is done to imperial, because I must interact with others that have no grasp (nor want) of metric. Go for it, Dude. By whatever system is easiest for you.
Bill Hudson​
Thank you Bill perhaps once i get more into this hobby and some free cash i will pick up a metric micrometer or 2 all of my instruments are in imperial which is the only reason why im asking for opinions. I have found metric to be easier for drawings myself but due to everything in imperial through my last 3 jobs its hard to tool up on it without a good reason for it.
 
I am a machinist/ fabricator in new product development for one of the US power sport companies.
The company is global so everything is designed in metric.
The funny thing is that quite often when I convert to inches (I just can't think metric) dimensions convert to a nominal standard size.
It seems like a lot of parts are designed in US, converted to metric, then I convert back.
 
That makes good sense. For conversion factors, multiply any dimension in millimeters by 25.4. In centimeters, you can multiply by 10 and then convert. For decimeters, by 100 then convert. The result will be in inches. Run out 3 or 4 decimals and round it as fits. Some places it matters, some it doesn't. That's essentially what I do with my models.

As an aside, I picked up a metric micrometer on eBay a while back for 3 or 4 bux. They paid shipping... It took 3 weeks plus to get here and I'm not sure how accurate it is. But I was getting it as a standby tool anyway. If I measure a 12mm shaft at 12.02mm, that's close enough for what I do.
 
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