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PaisleyPCdoctor
21-01-2018, 02:59 PM
I purchased these MGN15C a while back and didn't really know they were miniature blocks/rails.

I see by their spec they are not as strong as the normal size rails, bit don't know how to translate that into real world use.

Are these only good for 3D printers, laser engravers etc or am I underestimating them?

Would they fall apart on Z axis of a 2.2kw water cooled spindle?

Thanks.

magicniner
21-01-2018, 03:27 PM
9.81 Newtons equates to 1Kg Force,

link to spec to save anyone else searching for it -

https://www.hiwin.de/en/Products/Linear_Guideways/Series_MG/Block_MGN/21089/148411

1Kg is a bag of sugar or a Litre of water.

The loading on Z rails is not assisted in one direction by the weight of the bed so they are arguably more critical than X or Y and any flex in Z will eat the edges of your cutters if you use it for any metal.

PaisleyPCdoctor
21-01-2018, 05:56 PM
Thanks.

Future 3D printer project then.
The rigidity in them is impressive, though. Absolutely rock solid.

Thanks for the info.

Neale
22-01-2018, 03:18 PM
15mm Hiwin-style rails are almost certainly strong enough for a router. The problem, and one big reason why most people actually use 20mm for Z (as I do myself) is that 15mm rails and carriages give you very little space between the Z plates. It's difficult to fit a ballscrew and nut in the gap. Even with 20mm, you end up recessing one or other or both plates to give clearance.

Desertboy
22-01-2018, 05:55 PM
15mm Hiwin-style rails are almost certainly strong enough for a router. The problem, and one big reason why most people actually use 20mm for Z (as I do myself) is that 15mm rails and carriages give you very little space between the Z plates. It's difficult to fit a ballscrew and nut in the gap. Even with 20mm, you end up recessing one or other or both plates to give clearance.

https://www.ebay.co.uk/itm/15mm-linear-slide-guide-shaft-SBR15-1500mm-2-rail-4HSR15CA-bearing-block-CNC-set/232585268762?hash=item3627298e1a:g:8UcAAOSwNWxaJP-~

£120 for 2 1.5m rails and 4 carriages delivered from EU (No import tax) in 3 days just cannot be beat.

I have these very happy with them on my gantry and I have original Hiwin's on my Y and Z, 15mm all round. The carriages from the clone rail are compatible and vice versa with the Hiwin's.

I used spacers and recesses to make everything fit it wasn't difficult I'd say the bigger issue is greasing making some spacers is not difficult.

Depending on how you mount your Y axis the spacer issue only affects the gantry and Z axis at least in my case.

23650

The top block is loose in photo traced to one bolt was 1mm too long (I had to cut some down and missed one) I've fixed it and now everything is tight and rock solid.

The thing to watch for with all Hiwin's is what carriages you have so you can work out what height's you have for mounting.

I probably have a set of 4 18mm spacers with the correct hole pattern in left which are going free to a good home.