My first build, Alu Extrusions

[kjetor]

First of all, Hello everyone and greetings from Norway.

I have been planning a build for pretty long time, And now i have finally get together to start up with designing a cnc.

Will throw up some pictures first, Here they are for now. (This is just the design i have for now, so it will need adjustments)

163691637016371


First of all i need some opinions about the stiffness and all, As you might see, i have planned for a 4mm thick Alu plate along the extrusions to attach the rails to it.
The extrusions i have bough for now are 20x80 and 20x60, got 2 x 1500mm of both of em. I also have the ballscrew that is 1275mm long in total, and the rails that are 1250mm.

Have planned for C channeled extrusions for Y and Z axis, but not quite desided on that yet.

My main consernes are, Will this construction hold up ? Or will i need to just scrap the design ?
The area inside the frame is 1307x700 mm.

Hight from the table and up to the lower beam on gantry is 120mm.

Have bought 3 x Nema 23 420 oz for the job. and will be running either 1.5kw or 2.2kw water cooled spindle.
The table will be made of MDF, and will also be giving the build some low weight.

Ohh, And sorry for the spelling, lots of years since i was sitting on the school bench :joyous:

[mekanik]

Hi Kjetor
Welcome to the forum
If you could give the guys an idea of your intended use they will be able to determine if the structure is adequate.
It is usual to design and offer up for critique before purchasing your components. I am sure someone will be along to offer advice.
Regards
Mike

[kjetor]

Hi Kjetor
Welcome to the forum
If you could give the guys an idea of your intended use they will be able to determine if the structure is adequate.
It is usual to design and offer up for critique before purchasing your components. I am sure someone will be along to offer advice.
Regards
Mike

The parts i have for now are some parts i got cheap, so i snatched em while they where there.

What i am after is the chance of milling 5-10mm alu (in small cuts ofc) beside that i am after acryllic and mdf.

[mekanik]

Hi Kjetor
As no one has contributed i would recommend that you have a look @ some of the build logs for machines of a similar size to the one you intend to make, if you can run to the extra cost you are better served by staying well clear of the round support rail especially as you would like to be able to machine ally, also for a ridgid machine steel might have been a better and cheaper option for the main frame.
You will also require two ballscrews for the gantry to prevent racking. all this information is readily available on the forum, so i would recommend you forget about the design for the moment until you have done a little more research.
Regards
Mike

[sinnsvak]

Big difference between designing something from scratch, and then buy the needed parts, than have some parts to start with, and then design around that to achieve your goal.

The latter can be a lot more difficult, almost like a puzzle to crack, while following specific rules and demands to uphold the needs and standards of your build.

But by all means not impossible, but accept the fact that a little patience is needed before the final piece is in place. And please take advantage of the vast information that reside in all the build-logs already here.


Cheers :)