Need Help!- What plans to use with those linear rails?

[eranglr]

Hi there!
I purchased a few Iko linear rails and actually found some cnc goodies on a junk-yard

My dream is to build a rigid enough milling machine that would mill aluminium.

The minimum size should be 100x60 cm

Here are some photos of linear rails / stages I have!
Please advise - where to start from?

Is that a ballscrew I can use??



















This is actually a big 60x50 metal table, it might be good for Xy table?

[CarveOne]

The round rod looks like a 3/8" (0.375") ball screw if it is round at the bottom of the threads. If the threads are trapezoidal it is an ACME screw. It's a bit hard to tell from the photos but I'm thinking it is a ball screw.

CarveOne

[SatanKlawz]

looks like really slow acme thread to me.

[eranglr]

I tried looking for plans for building a milling machine, I've seen JOE machine and dozens of other plans, can you direct me to a good plans that will fit the linear rails / stages that i've got allready?

Thanks!

[hanermo]

Ive built one for steel. A big one.
Lots of work, parts cost a lot of money. Mine is very big, 2.4 x 1.4 m in size.

I know of no plans, and apart from mine only 5bears.com and Jose Rodriguez I know of has built one from scratch.

The linear rails are good.
IF you are willing to weld and build in steel, it´s easy. But lots of work.
IF you can spend some money for grinding, and are in the states, you can save a lot of effort.

The most important criteria is stiffness and mass.
In a nutshell, the heavier it is, the better it is.

Here I refer to a milling machine. If you build a heavy router, like a mechmate, you can work with alu, but relatively slowly.
It will be 10x poorer than a machine built for milling from scratch.

Building a heavy machine well is easier than building a stiff router. But it is a lot of work for a really good result.
A good result is one able to use industrial cutters and a Bp as a spindle, for example.
IF you just want a very lightweight one, with a hi-freq spindle, it (router) will work in that you can do hi-precision alu parts, but painfully slowly.

For a 50x100 (smallish) machine, with a good stiff structure, I would build a bridge mill (moving table), about 400-600 kg in mass. Expect about 400 hours work, and 2000$-3000$ in parts cost.
Commercial level results, able to use 10 mm endmills and a 3 Hp spindle. Maybe twice as accurate as a router, to 0.02 mm or 0.001", and 10x faster than a router. Good for doing parts for money.

[eranglr]

Do you have any other ideas which could take my linear rails to build a cnc machine?
Where do I even start from?

I have a solidworks knowledge.

[hanermo]

It all depends on what you want to do, and how well ...

Most people, maybe 98% here, do light woodworking machines.
A woodworking machine will run a router, and a router will cut alu, but only with small cutters and slowly burning up cutters.

I started by making a router, then a cnc lathe (7x light) then a full size milling machine (about 2000 kg), then a multi axis lathe and so on ...

The prob is, a lot of people say that you can make a fantastic geegaw for under 100$ and so on and it´s so accurate etc. This is less than the complete truth.

The bigger a machine, the heavier it must be, to the power of 3, to maintain equivalent rigidity.

If you want to get started, quickly, you could just build an xy router.
The choices are not all that hard; gecko 251s, a chopper PSU at 48V, some nema 23 steppers and belts and pulleys would get you a very accurate, precise, fast router (because of your linear rails).
About 400$ for 3 drives, motors and 6 pulleys + belts. Use HTD profile belts.
Want to make it good - build it on I beams. Get them surface ground flat somewhere, in the states it will be less than 100$, and you will have a better base than 90% of light machines.
Before grinding, weld them (the I beams) onto heavy flats on edge, from mild steel. This will make them stiff, and will give a hard spot, that you want in this case. It will keep the I beams surface from warping after grinding. Use heavy welds, after spotting end, middle etc.
The steel bits wont cost more than 200-300.

Dont worry about the weight. You cant make it too heavy.
After this, you have a good, solid machine as a base you can use in the future, and that will be good enough for commercial stuff.

Then when you start to add connectors, cables, e-chain, estops, bob´s etc. it starts to be more and more like a useful commercial machine, and you can go bit by bit. Stepper machine are safe, and wont do a runaway like a servo machine.

It all depends on what you need it for, and whether you have access to welding tools, small 4" grinder with flapper wheel to prep the steel, if you want to do a nice paint job, etc. etc.

For milling machines, you should compare the rigidity needed to something like an x3 mill, with a cast iron table. Thats what you want. What you build depends on your needs, skills, tools and budget.

I will be happy to advise, but some idea on what you want will help.

[LaserImage]

I don't think those parts will work for anything you might build. Please send them to me, postpaid, and I will gladly dispose of them for you...

[eranglr]

Can you please tell me what you think about the lowest price I should ask for the 2 x 1980 cm rails + 4 LWHT20 carts? on eBay or over here.

Thanks!

[LaserImage]

Originally Posted by eranglr x 1980 cm rails

You mean MM, right? What would shipping cost to get them to the US? I would possibly be interested in them, but more interested in the shorter ones in the photo - 30", 760mm, or so?

If you want to PM the shipping costs we might be able to work out a deal.

Gary