spindle rework

iain_downs

Hi, all.

I'm new to onShape and mainly new to CAD (and a hobbiest - so amateur all round)!  

I'm trying to design a lathe spindle.  

I've got a series of extruded, concentric cylinders, which is fine, but I now want to make some changes.  Specifically, I want to reduce the diameter of *part* of one of the cylinders (to allow for a smaller bearing at the back).  The options I see are to split the cylinder across and deal with each half (e.g. reduce the diameter of one half, to split the cylinder at a sketch and insert a new extruded circle (cylinder) between the two components or to 'thin' part of the extrusion.

I can't work out how to do any of these!  

Or some other way.

Any help much appreciated

Iain

andrew_troup

@iain_downs

Actually, I think I misunderstood your question: 

if you want to shorten one of the journals (cylindrical portions) and introduce a new journal of a different diameter, you should drag the Rollback bar (see help) from the bottom of the feature tree up to just after the original extrusion you want to shorten. This is like travelling back in time, except without the risk of meeting and perhaps killing one of your forebears.   

Edit the extrusion distance to be shorter, then create a new extrusion of the desired diameter and length on the end face which results.

Now when you drag the rollback bar down to include the next feature, it will "dangle" because it can no longer find the face on which it was sketched. Edit the sketch and pick the new end face of the preceding extrusion feature in the top rectangle of the edit dialog box.

Now when you drag the rollback bar to the bottom of the feature list, everything should rebuild OK. If not, share your model with the public, and post the URL (from the address bar at the top of the browser window) in this thread

Good luck!

andrew_troup

@iain_downs

If you have modelled the spindle from scratch in Onshape, you can simply edit the relevant sketch and change the diameter of the extruded circle. 

If you have imported a spindle modelled elsewhere, click on the cylindrical face and invoke "Move Face/Offset"

andrew_troup

@iain_downs

Actually, I think I misunderstood your question: 

if you want to shorten one of the journals (cylindrical portions) and introduce a new journal of a different diameter, you should drag the Rollback bar (see help) from the bottom of the feature tree up to just after the original extrusion you want to shorten. This is like travelling back in time, except without the risk of meeting and perhaps killing one of your forebears.   

Edit the extrusion distance to be shorter, then create a new extrusion of the desired diameter and length on the end face which results.

Now when you drag the rollback bar down to include the next feature, it will "dangle" because it can no longer find the face on which it was sketched. Edit the sketch and pick the new end face of the preceding extrusion feature in the top rectangle of the edit dialog box.

Now when you drag the rollback bar to the bottom of the feature list, everything should rebuild OK. If not, share your model with the public, and post the URL (from the address bar at the top of the browser window) in this thread

Good luck!

iain_downs

Thanks.

Iain