If you want a strong, stiff and relatively inexpensive machine, then don't plan on building a machine which is 1500mm across the x axis.

A standard OX can be cheaply strengthened by bolting steel plates on the Y axis and going with a larger solid X beam or building box frame from multiple extrusions.

Gerald's F-117 machine uses open rail so you could also choose a larger and stronger extrusion on the Y. Gerald is doing some great work in rack and pinion solutions. The frog build also provided some great insights and design on lead screw solutions.

When my rectangular steel tube machine is complete I will share the build cost information, but it's obvious the price will be dramatically more than the original OX. 1200mm ball screws $150 each, 1200mm linear bearings $80 each, etc.

I still maintain the OX is a great starter machine. The F-117 machines shows the OX can be modified to be a great production machine.

If I wanted a stiff and accurate production machine with 1500mm across the X axis, would plan on building a machine with larger stepper motors and much stronger than the OX. Talk with Gerald about his big nema 34 machine based on Joes CNC design.

We have all paid English Mini prices, so we have to live with a number of limitations about the design. The OX was designed to be a small and compact machine targeted at hobby CNC people.

 

Steve, all good advice.
Am looking at using 5010 extrusions for Y and X, openrail, rack and pinion w/ belt drives.
If I have to I will shorten the X but would like to be able to cut 48" wide but it is not a MUST HAVE
but it looks like the larger Joes machines use a 5010 on the X and Y.
I do need something much stronger than an OX.

 

Maybe not, but for about $5K I can buy a Chinese full size (1325) CNC with all the goodies on it (vacuum table and dust extraction) and a full year factory warranty, price CIF delivered in BKK harbor. Although they might have a bad name (why?) I have seen a bunch of them working over here for quiet some time and no issues (except the maintenance of course, the Thai are horrible in that) with them. Precise as you tune them in, very solid and heavy build. Including transport it would cost me al together not more than $6K to have it up and running in Nong Khai.

But…..I don't need one, …... yet.

 

"We have all paid English Mini prices, so we have to live with a number of limitations about the design. The OX was designed to be a small and compact machine targeted at hobby CNC people."

And that's a fact! I think the OX gives enough bang for the buck. If you want more, pay more. Simple as that.

 

I agree Paul, the OX is a great low budget machine. It has been a great learning experience, and a real fun project.

Any aluminum CNC built with 20mm extrusions will never be stiff enough for wide X axis production in my humble opinion.

It's like so many tools we buy. I'm now on my 3rd table saw, 20 years ago I started with a very light weight saw because that's what I could afford, 1 year later I upgrade to a serious hobby machines, and now I have an all cast iron and very heavy production machine.

They all cut wood but the production machine does this with ease and no vibration! But costs 6-7 times more and weighs 8 or 9 times more...

I have been debating linear bearings. Chinese linear bearings are much, much better than extreme wheels, and excellent value for money, but should I pay 3-4 times more for high production quality bearings?

It's all about setting reasonable expectations for how we plan on using a machine...

Mark never wrote fancy marketing brochures claiming his design could be scaled up!

 

dJMartin I'm really pleased this forum may have prevented you building a machine which is not up to your requirements.

For the CNC learning experience a narrow X axis OX is with the effort...

 

Not knocking the OX, came here with certain reqs and this post was about people with the same req.
I learned a lot and appreciate the knowledgeable people here who can discuss CNC without a pissing match.
Trust me, it is not common.
LOL!

I am actually designing some belt drives for the F117 and in communication with Gerald about it.
The design is simple enough it could work for most any machine with slight mods, we shall see what comes out of it!
That's all I can say at this time as I don't want to make trouble or promises I can't meet.

PS - This forum has no obvious way to quote someone. Is this the software or deliberate?

 

I look forward to seeing your ideas about belt drives. We all have requirements and dreams which evolve over time. Building the right machine is more important than just building a machine fast or cheap.

Lots of good people on this forum are willing to share ideas and offer helpful advice.

 

i have just finished rebuilding my machine, i also cut a hole in ally for the first time, it cut it like butter

6mm bit cutting 3mm deep @ 5000mm/min


4mm bit cutting 1.5mm deep @ 2500mm /m, unfortunately the video battery ran out before the cut had finished

 

Another test, I wound the speed up on the 4mm cut to 3.5m / min

 

Its ok, the only thing i would have liked is it to run slower than 10000 rpm

 

I'm in the planning stages and read half of the OX thread. My main goal here is to build guitars. This is only a hobby. I don't need a production machine that will spit out guitars faster than I can assemble them, but would like to make sure it will do precise work. I would be disappointed if the neck pocket was not a tight fit and so on.

I was thinking of building an OX like machine of 1000mm x 500mm with C-Beams. I'm not sure if I want to use the acme screw or belts inside the C-Beam.

Reading this, I'm wondering if I'm on the right track or not.

Any opinions will be appreciated.

 

All i wanted was a hobby machine that will do precise work, I do now, wish i never waisted my money on those silly wheels.
However I have learnt a lot, so its not a complete waste

 

I used supported rail but square rail would be better

 

At least the old stuff is not wasted, I have made my version of the stewmac true channel

 

I will check later, but it would be at least 5mm

 

i have just checked, its 5mm thick

 

Here's my OX doing finishing passes on a neck:



And cutting some inlays:



It's a fantastic machine.