No excuses steel frame

#1

I want to build CNC using steel hot rolled angle 50x50x5 or 70x70x8.
Ye ye ye. It will be CNC made of cheap materials mostly from hardware store and china :stuck_out_tongue:
Rollers 8 for X 4 for Y. 4.5$ each --> 54$:


•V roller for sliding gates 90°. 68 mm diameter.

Cardan

https://pl.aliexpress.com/item/4000107089566.html?spm=a2g0o.productlist.0.0.64fb20848VHZvt&algo_pvid=6f26ae33-9c32-42aa-844f-076b8634626a&algo_expid=6f26ae33-9c32-42aa-844f-076b8634626a-31&btsid=fbdb12ca-f6cf-4bf9-8ce2-2e81c139b532&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_52

•Cardan clutch between engine and TR screw. Size will be picked after TR screw.

I’m open for any suggestions, how to mount angles to table. I can connect metal angles just like the top beam of sienci mashine (back to back). Maybe that will give some stiffness. In that case i will use 6m of steel angle. (the only size my shop sell is 6.20m)

When i don’t connect them i will save 2m for future projects.

Motors. At the moment i really get used to motors with worm gear plus two channel encoders.
or

57A3EC stepper motor

https://pl.aliexpress.com/item/33014208540.html?spm=a2g0o.productlist.0.0.295d1480plkbnj&s=p&algo_pvid=679fea67-f8b3-42e2-a086-e8bf77cdc50a&algo_expid=679fea67-f8b3-42e2-a086-e8bf77cdc50a-0&btsid=a073d238-2d63-4126-88b5-da65f8fe03f5&ws_ab_test=searchweb0_0,searchweb201602_7,searchweb201603_55

#2

Just a quick note about using hot rolled steel angle.

Hot rolled steel angle is:

  • Not very straight
    -Do not have clean sharp edge angles for running v-wheels on
    -Tolerances for the width of the angle vary enough that you will have tight and loose spots along the rail

Hot rolled steel angle is, from what I understand, folded bar to make the angle, which is also doesn’t hold the best tolerances.

We use aluminum extrusion because:
-Extrusions have a high consistency for width and straightness
-Sharp clean angles where the rollers go

I would recommend using aluminum extrusion instead, but rather reinforce the rails if need be.

#3

yes you are better off using aluminum. Unless you have the ability to machine the steel down to the correct size. Theoretically a steel cutting table saw might do the trick, but they are not sold, you have to make your own out of a metal cutting hand held circular saw.

sounds like more trouble than it is worth

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#4

Ok, I can make sharp edge with table saw. Not hard to do :P. That way i can get consistent edge
I’m preparing table under (15mm) plasma cutter.

New plan. I will test that solution on old table saw.
obraz
I will mount hot rolled steel angle on side to make carriage on 4 wheels. That way i will have somthing like sliding table that take away a weight of wooden block. That solution will be upgrade to my table saw and test for future use in CNC.

#5

Wow your braver than I am. That thing looks scary.

#6

you will need a reduction wheel so it spins MUCH MUCH slower and a steel blade, and lots of lubrication safety gear and blade should only be about 25mm high, good luck.

#7

No. Im not mad :stuck_out_tongue: (I hope You didn’t thought i was gonna do it on this madness)
I will use professional table saw to make edges on steel angle :stuck_out_tongue:

This picture was just demonstration of machine i want to upgrade to test metal sliders.
I’ve got normal table saw witch 2kW induction motor for woodworking. I will mount metal cutting blade, lower it to best height and cut only the tip of iron angle to make it flat.

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#8

Hi Marcinan:
I’m not sure what kind of precision you want, but be aware that when you start machining rolled steel, you are removing the surface tension of that edge. Your angle iron rail will open up, ie. become bowed, especially over 1m length.
If the rails would be square, you could “reduce” this effect by machining all sides evenly.
Extrusions would be my choice, but if you’re making a plasma cutter, perhaps steel angle iron is good enough. I wouldn’t machine it… Knock off the burrs…use those steel V rollers, and go for it.
:+1:

Hansi

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