Home Improvement

Home Improvement

# How to use a protractor (angle finder) for miter work (molding)?

Customer Question
How to use a protractor...

How to use a protractor (angle finder) for miter work? I've been trying to figure out this protractor to no avail. The guy at the hardware store said all I do is take the figure and cut one angle at that # and the other one that would add up to 90.

Example: The number the protractor gave me was 42, so I cut one piece of wood at a 42 degree angle. The other I cut at 48 as per his instructions. The fit wasn't even close. Please tell me what I'm doing wrong.

Submitted: 10 years ago.Category: Home Improvement
Show More
Show Less
4/3/2007
Home Improvement Expert: Mr. Mike, Civil Engineer replied 10 years ago
Mr. Mike, Civil Engineer
Category: Home Improvement
Satisfied Customers: 1,387
Experience: Homeowner and fixit fan. What works is what I am interested in.
Verified

The purpose of miter work in molding is to match the cut ends of molding pieces so they fit into a giver corner.

Assume for the moment that you are doing some baseboard molding. The first question is, what is the angle between the walls where they join at the baseboard. Hopefully it will be 90 degrees if the walls were built "square", but you'd better measure to be sure!

Say the angle IS 90 degrees. Take the baseboard pieces and physically lay them in place near the corner. Think about how you want them to fit together. It would be nice if the length of each cut were the same. Half the 90 degrees is 45 degrees, so that would be the angle of each cut. BECAUSE IT IS EXACTLY 45 degrees, it doesn't matter where you place the "center point" of the protractor. Draw the cut line on each piece, put them physically back in place in the corner, and get a mental picture of how they will join after the cuts are made.

Now, what if the corner ISN'T square? Say the walls join at a 94 degree angle (the corner is 4 degrees "bigger" or "wider" than a right angle). Now your cut has to be at 47 degrees (again, HALF the angle of the walls), and it will matter where you put the center of the protractor and where you measure the 47 degree angle from. Once you lay the baseboard down and look closely at the cut lines you will need, you will see where the center has to be and where to draw the 47 degree line.

The center of the protractor has to be where the tips of the cut ends meet! The angle of the cut has to be half the angle of the walls (this assumes each baseboard is the same thickness!).

Mr. Mike, Civil Engineer
Category: Home Improvement
Satisfied Customers: 1,387
1,387 Satisfied Customers
Experience: Homeowner and fixit fan. What works is what I am interested in.

Mr. Mike is online now

A new question is answered every 9 seconds

• Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
• Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

## What Customers are Saying:

You did one super job of explaining to me everything there is to know about this fridge. I'm looking forward to asking you questions in the future.

JimmyBagley, IA

Thank you for the expeditious answer. It's good to know you're out there and awake in the wee hours when I finally have time to ask questions about my Jenn Air.

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

< Previous | Next >

## Meet the Experts:

Brian

Architect

2,153 satisfied customers

Licensed Architect- 17 years, L.E.E.D. AP

The Home Smithy

Home Builder

2,084 satisfied customers

#1 Home Improvement Expert 30+ years experience

Steve G.

Handyman

221 satisfied customers

VP of electronic repair company and home theater advisor.

StructuralEng

Civil Engineer

14 satisfied customers

Eric M. Bright

We Don't Comprehend the Word Can't!

1,734 satisfied customers

I've been been doing things for my clients that others have said cant be done for over a 1/4 Century

Phil

Mechanical Engineer

682 satisfied customers

Retired contractor, 51 years experience

Rich

Home Improvement Enthusiast

674 satisfied customers

Over 35 years construction and home maintenance experience

< Previous | Next >

Related Home Improvement Questions
I'm having some issues with my water heater and needed some
Hey Pearl, I'm having some issues with my water heater and needed some brief guidance … read more
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
I am trying to remove a Kohler toilet seat that may be
I am trying to remove a Kohler toilet seat that may be original 1989 version. The top of one side of the achor arms actually has a slide--so it can at least partially slide out. I got the nut off that… read more
eauto
self employed
High School or GED
74 satisfied customers
My wife put metamucil down our sink and it's gelled and
Hi. My wife put metamucil down our sink and it's gelled and clogged up about six feet of pipe.I have snake but it just seems to cut its own hole through the gel and doesn't take any back with it. Does… read more
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
My garage door remotes work very intermittantly- I have
My garage door remotes work very intermittantly- I have changed the batteries & tried to renew the operating code based on the insrux in the manual but no luck- are my remotes too tired? They are over… read more
Eddie
Home Improvement Contractor and Repairs
High School or GED
1,052 satisfied customers
We are remodeling my home and replacing baseboards and trim.
We are remodeling my home and replacing baseboards and trim. This past summer I caulked all trim with White Lighting caulk from Lowes. The caulk is now separating and leaving gaps as if it was never c… read more
Eddie
Home Improvement Contractor and Repairs
High School or GED
1,052 satisfied customers
My taco pump spins for about 3 seconds, shuts off for about
my taco pump spins for about 3 seconds, shuts off for about 5 to 10 seconds then repeats the process. why wont it stay running? … read more
David Bowden
Owner
478 satisfied customers
I just replaced the dual gas safety valve, because the oven
I just replaced the dual gas safety valve, because the oven was not lighting. When I tried the oven it will come on but not stay on. At a loss to fix it. Any suggestions? … read more
David Bowden
Owner
478 satisfied customers
We are wanting to temporarily remove a stairlift (a Har) The
We are wanting to temporarily remove a stairlift (a Har) … read more
Machinc
Retired
952 satisfied customers
An exterminator came in today to deal with the roaches. Now,
An exterminator came in today to deal with the roaches. Now, should I remove this bait thing I assume after a while or just leave it in place?… read more
David Bowden
Owner
478 satisfied customers
Removed old laminate floor to replace it, when I picked up
removed old laminate floor to replace it, when I picked up moisture barrier it was wet like sweat. Had a plumber in to check if pipe under house were broken and everything is fine. Now floor is bare j… read more
canuck the pro
251 satisfied customers
Perhaps a foundation issue... I had a large area of a 19
Perhaps a foundation issue... I had a large area of a 19 year old porcelain tile floor suddenly ‘pop up' from a concrete slab. It popped up 4-6 inches immediately after unusually cold (14 hrs below 32… read more
Machinc
Retired
952 satisfied customers
Two coworkers were arguing about clearing plugged lines
Two coworkers were arguing about clearing plugged lines today. The line contained fats, oils and grease. One coworker said you can't use steam because the plug prevents the steam from flowing. Since t… read more
canuck the pro
251 satisfied customers
The backflow preventer on the sprinkler system froze in the
the backflow preventer on the sprinkler system froze in the recent storm and is now leaking. I opened the plastic top after turning the water off. What now? … read more
Rick
Supervisor
22,917 satisfied customers
Power went out on one circuit changed broken wall plug no
Power went out on one circuit changed broken wall plug no power unless I put the tester to the black wire and the ground … read more
David Bowden
Owner
478 satisfied customers
I'm looking to program a garage door opener replacement,
I'm looking to program a garage door opener replacement … read more
Eddie
Home Improvement Contractor and Repairs
High School or GED
1,052 satisfied customers
My thermador stove top is clicking and there is sparking to
My thermador stove top is clicking and there is sparking to the burner. The clicking goes away when I turn on the flame … read more
David Bowden
Owner
478 satisfied customers
We have two showers both with wands. When we use the master
We have two showers both with wands. When we use the master shower there is no problem the shower starts and shuts off properly. When someone is using the guest shower the shower in the master (which … read more
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
I have an indoor/outdoor lemon tree. It has done great for
I have an indoor/outdoor lemon tree. It has done great for years and years. Since I live in Upstate NY, I keep it outside from late June- early Sept and then inside for the rest of the time. I have ha… read more
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less