CNC Frame Design Help

**zhenning** · 20-12-2015

Some updates on v2. Any feedback is welcome. By the way, any consideration in sizing the gantry and linear profiled rails? Currently, I modeled it with HGH35.

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**Rufe0** · 20-12-2015

Originally Posted by zhenning

Some updates on v2. Any feedback is welcome. By the way, any consideration in sizing the gantry and linear profiled rails? Currently, I modeled it with HGH35.

Kinda hard to see whats going on but you definitely need a wider gantry with 2 carriges per rail like this

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**JAZZCNC** · 20-12-2015

Don't need HGH35 that's massive overkill. 20mm will be fine 25mm Max. After that your just wasting money and increasing weight for little to no benifit.

Also Like Rufe0 mentions you need 4 bearings per axis on all axis.

**zhenning** · 26-12-2015

So, I have changed the rails from HGH35 to HGH25. Added 4 bearings on the rails. The gantry consist of 3 8080 profile and hold by a 20mm plate that sits on the profiled linear guideway on both ends. For the endstops, i am thinking of some capacitive sensors and the motors, i guess a Nema23 2N.m. would do?

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**Rufe0** · 26-12-2015

Hello
You could extend these rails to get alot more travel.

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Not sure these bits are really providing any extra suppprt

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I think these are the motors for the bed, I'm thinking that you've just not drawn the supports for them. If you moved them to the bottom facing up you could get more gantry travel.

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If your gantry went all the way forward it would give you two advantages, you could fix work to the front of the machine, so that you can work on all 6 sides of things and you could possibly mount a 4th axis on the front in the future.