1. Metric machines

Hi guys,

I've had a lot of people who live in areas that use the metric system ask what changes might need to be made to construct the machine. I don't know if it is feasible to ever have a metric specific version of the plans, as I'm guessing there is a lot of variation in what sizes of metal are available in different parts of the world. So I though maybe it could be valuable to have a thread where builders who are dealing with metric conversions can share experiences and help each other out. I know there have been at least a few machines built in metric countries. I know of at least 2 in Australia (by builders who haven't yet been active here in this forum.) I don't know how much help I might be able to offer, but I'll comment where I can.

One initial comment I'll offer is that the machine relies on the thickness of the metal stock to locate everything correctly in space. Different size stock will throw everything off, needing either shims, or moving hole locations slightly.

Also, if anyone who is building in metric could post what sizes of metal and other parts they have available, it might be very helpful in determining what modifications you might need to make. It will also help me see if there is enough consistency in available sizes to eventually issue a metric set of plans.

-Bob

2. This is a response to a post in another thread. Thought I would answer it here to keep the information organized.

what is the circumference of timing belt pully

i have plans and now converting them to metric

I am replacing all 1/4 to m6 and all 10-32 to m5 or m6. Is it okey ?

I am doing a round figure in mm like 152.4 converted to 152 mm

help me more if you can in convertion.

parallel_lines if you need my metric plans i will be happy to provide them to you
Karandex,

Your 1/4" to m6 and 10-32 to m5 should be perfect.

The timing pulley has a pitch diameter of .637".

-Bob

3. i going buy your statement that there is 1/32" tolerance to all things. so i am rounding up measurements.
I think i can find the most stock thickness required. finally i am giving it to a workshop to fabricate all parts.They are skilled but they dont work in inches. that is problem. stock can be made to inches but not workers.

Again i am thinking of makin them as kits. please tell your opinion or improvements in structures ( like removing and adding some parts as one piece.also as i see in other post counter bore is useless if the job is done by pros)

4. Karandex,

It would be a violation of Bob's copyright under international copyright law to make kits of his plans (or any derivative) without his permission!

Regards,

Randy

5. i already asked his permission but he is not responding. i have offered him royalties also, but he say that making kit is hard job and cant be done. but here the labor is so cheap i can make cnc in large amount, but he is not getting it

6. Karandex,

Great. In that case I hope it works well for you!

Regards,

Randy

7. metric questions

Hi all,
well now ive finally finished the workshop i need a machine to put in it and this router fits the bill nicley.

so i got the plans and found the forum, so my question is to all you metric builders is, what sizes did you find in the extrusions? I have done the conversions but am having trouble finding ones of simillar sizes. No point doing all the research if people are willing to share size equivillents and purchase locations. I am in NZ and i see there are a couple of builders from here on the forum. How are you going with your builds? and are you sticking to the plans as much as possible or she'll be right mate approach.

would it be worth looking into importing the actuall sizes just to make things easier in the long run?

thanks in advance for the help and im sure there will be many many more questions.

Thanks

8. I know of at least two builders in Australia who have completed machines. I know that one had access to a machine shop and milled down stock to the inch sizes. I don't know what he used for a gantry tube size. I believe the other guy ordered the metal from the US and had it shipped. If it is at all possible, using the inch-sized pieces will avoid a LOT of headaches.

Also, the issue has been briefly mentioned in couple of other threads. Check out the thread titled "Build thread 2" (post #19) and you'll see that Idanut decided to import the metal from a US supplier. In the thread titled "Momus Design + AC Servos" in the very first post vigen20 mentions adapting the design to metric sizes, but doesn't give any details. Perhaps he could be persuaded to post some details here..?

Are there certain metric sizes that you know are readily available to you in NZ? I would probably start by going through each size of metal listed in the bill of materials and seeing what you have available locally that is a close match. I'd probably also price those out and then see how the total cost compares to the cost of importing the metal from the US. Imposting would be the simplest solution from a construction standpoint, so I'd see how it compares cost wise. I know that even here in the US it is typically far cheaper to order online and pay for shipping costs than it is to buy locally. Online you can order exact quantities needed, whereas locally you often need to buy full lengths.

-Bob

9. Sorry guys for delay in replies...
I can't tell you at the moment what are the sizes of steel I have used for my build but I promise I will post them here tomorrow evening at the latest....
Regards

10. Perhaps the right question to ask is "What are typical dimensions of material available in Europe and Australia?"

For instance, if 19 mm square bar stock is easy to find, it is a fairly direct replacement for the ).75" stock. If its 20 mm, perhaps a small alteration to the parts is all that is necessary or it could also be fine to use.

For those of us insulated from these issues in the US, it is hard to assess without some information on material availability.

I would think that many, if not all, of the parts would work fairly well at the nearest metric size.

One should already note that the bearings are metric with an 8mm bore but fit a 5/16 inch bolt just fine. So, you could say that the design is already partly metric.

11. I have done some more looking into importing the sizes required, but the import cost is going to be expensive so i will have to look at metric sizes. There are some sizes with only a few MM diffrence so i can compensate for that but others i cant find ( on the net ) so will have to do some ringing around to see what they can get and costs involved.

Thanks