Draw Whorl
Draws spiral threads with tapered section (if needed) for making screw and bolt threads.
Draw Whorl

Draw Whorl plug in/extension is a simple way to generate threads for your models. It allows fixed-radius thread section, as well as an optional tapered-thread section. You can specify the starting and ending radius for the tapered section, and how many revolutions of the fixed-radius and tapered-radius sections. You can specify the pitch of the threads, the length of the threads, and the width of the outer edge of the threads. The help page has additional tools to help you generate settings files for standard bolt and screw threads.


Scott B's picture

Just downloaded the current plugin and its working good in Version 18.0.16976

Pretty cool plug in. Works very well. THanks for making this.

Aaron M's picture

This is a fantastic tool and the UNC/UNF windows are great. I know it may be a bit of a stretch, but functionality to define a number of different threads would be fantastic (i.e. ACME, NH, SIPT, etc.).

All the same, this tool has saved me immeasurable time and effort in the short time I've known of it.

kapenske ..'s picture

A useful extension. I guess for things like spiral stairs (or similar?) the terminology is fine. Coming from a manufacturing background I find the menu selections to be confusing. Using it for threaded components like screws and bolts it does not use industry standard terminology. Thread "height" is acually a distance from minor diamenter to major diameter. Edge height would be thread "crest". Threads don't have a length, they have a width. Length would usually indicate the overall lenght of the threaded item. That being said, I comment only with the perspective of screws and bolts. And if you're so inclined, it's easy enough to change the menu names in the program code.

thank you for that super plugin! Nice work!
Greetings from Germany


Amazing plugin. Thank you for sharing.

Makarand A.'s picture

Hello Rick,

Thanks for such a good plug in. It has helped me and others a lot.

I have further questions on,

1.How to make Left hand threads
2.Can I make male threads and subtract it from a block to make female threads.

Please guide me to resolve these issues.

MaKarand Acharya

Craig C's picture

Scale it through itself - negative '1'. Solved. Left hand thread.

I was able to make Left hand threads by adding a "-" before every dimension.

Tobias S's picture

Hi - this tool is brilliant. It does exactly what it says on the box.

One comment on how to create a "solid". The above instructions, I think are not quite correct.

I created a solid by doing the following:
1) create first whorl
2) create second worl using the same settings as the first EXCEPT for the following:
a) start radius (2nd) = start radiun (first) - tooth lenght
b) end radius (2nd) = start radiun (first) - tooth lenght
c) tooth length (2nd) = 0
(keep the tooth height the SAME as for the first whorl!!!)

--the second whorl should be created inside the first one--

3) explode both whorls
4) now close off the end caps of the two whorls
5) use the solid inspection tool

Makarand A.'s picture

Dear Tobias S,

Thanks it helped me to make one

Best Regards,
Makarand A

gary g's picture

I'm using your plug in with Sketchup Pro 2017
I was able to make 3D printed threads thanks to your thread generator in the
help section of your plug in.

Do you have any plans to create a metric thread generator?

I discovered the way to make the whorl into a solid in sketchup.
That made life quite a bit easier.

I like your plug in

Hi Gary, (Or anyone else who can help)
Could you please tell me how you made the threads into a solid? It may also benefit me to ask: How do you make a core for the threads to actually turn them into a bolt or nut? I have struggled with this for days! I am kind of new to modeling so any help would be greatly appreciated.

gary g's picture

Make a Whorl . It will be a group.
Make another Whorl, but change dimensions Start Radius and end Radius should be
End Radius - Thread Length = your new radius.
Set Thread Length to 0
Set Thread Height to 0
Then make another Whorl.
You should end up with what appears to be pretty close to a thread form.
Explode both of these forms and make a new group out of them.
Close the ends and you should have a solid.
I do also use Solid Inspector to correct internal walls and reversed faces that always seem to happen.
I hope this helps you.

SwissRS3's picture

not working with 2017, but works with 2016

Walter A.'s picture

not working with 2016

Netbeese's picture

Any update for a version for Sketchup 2016 ?

ezz-aldeen A.'s picture

not work sketchup 2016

Dan C's picture

Hi Rick,

This plugin works a treat, and I can make 'male' threads pretty nicely. If I put a negative sign in front of the start and end radius, I'm finding that sketchup will render a pretty good looking 'female' thread if I want to draw a tap-hole. However, I'm having trouble getting the .stl to slice with xyzware. Can you tell me if I'm creating the tap-hole correctly?

John Lander's picture

You can get the .stl Exporter Extension. It's made by SketchUp, so it should be compatibe and work with what you're doing.

machoneboard .'s picture

Hi Rick. Great extension and thanks. Instruction box still not there on my version, glad it will be.

Rick's picture

I'm sorry about that. I am having some Javascript issues between platforms. I just got out the hospital, and haven't been able to work on it for few weeks. I will try to resolve the issues soon and re-submit an update. Do you use a Mac? If so, I can send you the version with the feature you requested. Still trying to get the Windows side working with new web based dialog.

Michael H's picture

Hoping you are doing well, I would love the updated version if you have time. Thanks

Badr Z's picture

Dear Rick,

I want to hug you for creating and sharing this pluggin

Badr Z's picture

Dear Rick,

I want to hug you for creating and sharing this pluggin

atek s's picture

I like ur plugin do u have created if yes then i have one more plugin u can make and maybe many people will like it. Hope u know blending tool in illustrator which blend from one end to other end. Can u make the blending tool which can blend the shape from smaller to bigger and make parts in between as we can set in that. If u interested plz tell me

Mathew S's picture

I can not thank you enough for this amazing plugin!!!! You have saved me hours. Thank you!

Rick's picture

I'm glad you like it. Thanks for the feedback.

Martijn D.'s picture

Very nice plug-in! I use is a lot to draw threaded rods/bolts/tap-holes. Thank you very much. If I could do 1 feature request, please add the picture showed in the help and above here in the Whorl dimensions pop-up. This feature will make my life a lot easier. Thanks again for this wonder full plug-in!

Rick's picture

I added the picture you requested. I posted it to Extension Warehouse, but it hasn't updated yet. The new version with the picture is 1.0.8.

13298 users
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Draw Whorl (1.0.7); November 30, 2015
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Hi, I am a support systems administrator for a university in-plant offset and digital printing operation. My hobbies include photography and woodworking. I use SketchUp to plan woodworking projects, and love making models. I recently made an SketchUp extension for creating threads for bolts and screws called DrawWhorl.
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