Communities

Writing
Writing
Codidact Meta
Codidact Meta
The Great Outdoors
The Great Outdoors
Photography & Video
Photography & Video
Scientific Speculation
Scientific Speculation
Cooking
Cooking
Electrical Engineering
Electrical Engineering
Judaism
Judaism
Languages & Linguistics
Languages & Linguistics
Software Development
Software Development
Mathematics
Mathematics
Christianity
Christianity
Code Golf
Code Golf
Music
Music
Physics
Physics
Linux Systems
Linux Systems
Power Users
Power Users
Tabletop RPGs
Tabletop RPGs
Community Proposals
Community Proposals
tag:snake search within a tag
answers:0 unanswered questions
user:xxxx search by author id
score:0.5 posts with 0.5+ score
"snake oil" exact phrase
votes:4 posts with 4+ votes
created:<1w created < 1 week ago
post_type:xxxx type of post
Search help
Notifications
Mark all as read See all your notifications »
Incubator Q&A

Welcome to the staging ground for new communities! Each proposal has a description in the "Descriptions" category and a body of questions and answers in "Incubator Q&A". You can ask questions (and get answers, we hope!) right away, and start new proposals.

Are you here to participate in a specific proposal? Click on the proposal tag (with the dark outline) to see only posts about that proposal and not all of the others that are in progress. Tags are at the bottom of each post.

Comments on How do I draw a perfect circle on a square of plywood?

Parent

How do I draw a perfect circle on a square of plywood? Question

+3
−0

I'm working on a string-art project on a 3-ft square of plywood. It will have brass nails in a circle with different colors of string connecting the nails in a pattern.

I'm trying to figure how I can draw large enough circle on the plywood. I've thought about:

  • Finding a bowl to trace, but none in my house are large enough.
  • Using a compass, but again, mine isn't large enough.
  • Freehand drawing the circle, but it comes out too imperfect.
History
Why does this post require attention from curators or moderators?
You might want to add some details to your flag.
Why should this post be closed?

0 comment threads

Post
+2
−0

When I needed to cut a 4' circle out of the middle of a sheet of plywood, I fabricated a compass by tying a long-enough piece of non-stretchy string to a tack or finishing nail -- I forget which, but it was something small enough that it wouldn't leave a mark on the other side of the plywood.

To the other end of the string I tied a pencil at the desired radius. Working on the side of the plywood that I designated as the back, I found the center point by measuring, drove in the tack, had a friend hold it in place just in case, and walked around the board tracing the line with the pencil. Tip: do this at sawhorse or table height; you want to be able to walk around it and maintain consistent tension while doing so, not crawl around on the floor.

Measure twice, cut once: after I had a line I could see, I measured the diameter in a few places to convince myself that any variability was within the margin of error that cutting it out with a jigsaw would produce. (Maybe there were better ways to cut it, but a jigsaw is what I had.)

History
Why does this post require attention from curators or moderators?
You might want to add some details to your flag.

2 comment threads

How did you ensure the pencil stayed straight? (2 comments)
Will this work for the front? (2 comments)
How did you ensure the pencil stayed straight?
Stephen Ostermiller‭ wrote over 1 year ago

How did you tie the pencil to the string? I'd think you'd have to tie it pretty near the tip to ensure that the pencil doesn't wobble around and make your circle less than circular.

Monica Cellio‭ wrote over 1 year ago

Yeah, it was near the tip, right before the narrowing that leads to the point.