Introduction+some help needed:)

lamesh99

hello, everyone! my name is marko, i am from croatia. i normally use SU for my hobby, which is CNC machining. now, since it is only a hobby, i use the free version of the software. nevertheless, i am VERY satisfied with the simplicity, intuitiveness and usefulness of the SU.
i am having some trouble, though. i have been trying to model myself a small lathe chuck for the past few days, but with little luck. the item i am having problems with is the screwplate, the part which turns and contracts or expands the jaws. essentialy, the screwplate is the round plate with a central hole, one side is made like a gear, and the other one as a screw (photo will explain this a bit better, circled in red). can someone explain this, please? or even make a model, if not too much a problem.
Thanks!

glava tok ozn.jpg

TIG

You need to get a Helix making script - try DrawHelix14...
The make a face perpendicular to the start of the helical curve and use FollowMe to make the spiral form...

lamesh99

wow, that was fast. thanks for your reply! another thing, if i may bother you a bit further, how do i make the other side? other side needs to be like a horizontal screw, essentially lines (teeth) spread across the circle in an equal manner, if you understand me.
thanks again for your help!

lamesh99

not sure if i made a mistake somewhere, or posts need to be approved
anyways, thanks for a quick reply, You helped A LOT. if you can help me with one more thing: other side of the plate: how do i make a pattern like this? this is, essentially, a number of lines (extrusions) spread evenly over the circle, or the rim, not sure how to describe it (pic will say more).
thanks again!

Gaieus

Best is to make a component of a "tooth" there and make a radial array.

If you hide some inner faces and matching edges, you can even get a smooth transition between the wheel and the teeth.

cogwheel.skp

lamesh99

thanks for all the help, guys! i made a model of my screwplate, i'll post it here so someone else can use it. one more question, how can i taper the top of the gears? i tried a bunch of plugins, but none of it seemed to work for me.
anyways, thanks for the help!

simple gear+helix screwplate.skp

TIG

lamesh99

this looks great. how did you apply the tapers? i can't really tell from the pics. Thanks!

TIG

I edited the one 'two-teeth-component' part.
I drew the edges and PushPulled the 'teeth' up - much as you had inside your groups.

I then used the Tapemeasure tool to offset guidelines [seen dotted] from the 4 edges inwards by 1mm [you choose what dimensions you want].
I then drew another line over each guideline on the top surface.
I then 'reformed' the teeth with tapers, one at a time.
I selected the unwanted edge [at the right-angled corner] and use the Move tool to relocate the edge over the line draw where I want the taper to end on the top face.
The vertical face slopes over with the moving edge that it's attached to, the end faces of the teeth also distort to follow the new tapered form as it then narrows near the top.

Completed the tapering for all 4 edges.

Note that there are several other ways of making these 'tapers', but this one is quite simple...

Finally Erased the guidelines and then exited the component edit.

Used Rotate+Ctrl x23 to make the copies of the component around the circle, snapping to the start/end of the two-teeth-component.

Note how adjusting one instance will change all the others at this stage...

Finally Explode the components into one collection [if you want]...

lamesh99

i did it like that exactly, but i obviously got it wrong somewhere. when i used move on the top lines, a part of the small plane on the outside rim of the tooth was erasde. i'll just keep trying:)
Thanks again for the help!

lamesh99

i got it right, finally:) thanks, again!

Jean Lemire

Hi folks.

See this SU file for ideas.

The same principle could be used for tapered teet instead of pointed ones.

Horizontal gear.skp

lamesh99

thanks for all the help!
one more thing is very interesting to me: SU physics. i would like to make a model with moving parts, hinges etc. any advices?

mitcorb

Hi, lamesh:
You asked for advice regarding Sketchyphysics. My advice: Persevere. Read the SP subforum, check out the FAQ, Watch the YouTube videos. Dive in, and ask questions. There are several folks with plenty of insight there.