Problem with angle cuts on my circular saws. - Woodworking Talk - Woodworkers Forum
 
Thread Tools Display Modes
post #1 of 18 Old 01-30-2013, 08:57 PM Thread Starter
Dumbest Smart Person
 
Join Date: Jan 2013
Location: DFW Texas
Posts: 434
View RobinDobbie's Photo Album My Photos
Problem with angle cuts on my circular saws.

I decided to skip the introductions forum and just get right to the question. Well, that's just rude of me. Sorry. Hi! My name's Robin, and I'm building some speaker cabinets. I've successfully made a few in the past, but I'm striving for a higher level of accuracy, now. I do plan to stick around and absorb as much knowledge as I can. I might possibly ask more questions!

Here's 3 things I'm stumped on right now:

Excess friction between the saw and work piece.
Streaking from the aluminum apparent on the work piece.
Problems getting a consistent angle across the board.

I've been trying to put some angles on the edges of 23/32" plywood. Earlier today, I made the first try with an old Skill saw that used to belong to my grandfather 10+ years ago. It had a little bit of corrosion on the base. While sliding it across the wood(smooth, sanded pine), I encountered random friction. The whole cut seemed more difficult than I felt was reasonable, but some areas were "sticky" enough that I had to really apply firm pressure to keep the saw from altering course. To counter this, I smoothed the base with some steel wool. The rough areas were then smooth to the touch, yet the friction was still a problem. The work holding the saw doesn't bother me, but the aluminum plate leaves gray streaks on the wood does.

The consistent angle problem is more serious to me than the other stuff. I noticed the base of the old saw was a tiny bit rickety. Thinking the course of action with the least hassle would be just to buy a new saw, I did. Bought a beautiful DeWalt. It's doing the same exact thing. Now, the first cut was amazing. Smooth travel, and the angle was consistent all the way. I felt good about my purchase! The second cut didn't turn out so well. Every cut I double check the guide position on both ends of the board, before and after tightening the clamps. The position was exactly the same. Yet, on this second cut, rough travel, light grey streaks, and most importantly, uneven edge angle.

Start of the board is perfect.



End of the board makes me want to pull my hair out.

\

I checked the position again and everything's perfect. Except the cut.

Last edited by RobinDobbie; 01-30-2013 at 09:03 PM.
RobinDobbie is offline  
Sponsored Links
Advertisement
 
post #2 of 18 Old 01-30-2013, 09:20 PM
Senior Member
 
Dave Paine's Avatar
 
Join Date: May 2012
Location: Eastern PA
Posts: 7,222
View Dave Paine's Photo Album My Photos
Welcome to the forum, and most folks do post their introduction in the Introductions forum. What a concept.

The start of the cut is good, since the blade has not had chance to be deflected.

By the end of the cut, the blade looks like it is being deflected.

Circular saw blades are thin, to minimize the power required by the saw. Thin also means potential for the wood pushing the blade.

I would make this cut on a table saw with a full kerf blade - 1/8th in.

You likely do not have a table saw.

So plan "B" is to make the cut wide with the circular saw, then create a bevel shimmy for a router and finish with a straight cut bit to get a consistent angle and decent face.
Dave Paine is offline  
post #3 of 18 Old 01-30-2013, 09:52 PM
Member
 
Join Date: Jan 2013
Location: Southeast Kansas
Posts: 45
View wood8671's Photo Album My Photos
Friction? Is the blade new or 10 years old?
The stricks can be fixed with tape on the bottom of the shoe, better yet put cardboard between the saw and your material
wood8671 is offline  
Sponsored Links
Advertisement
 
post #4 of 18 Old 01-30-2013, 09:59 PM Thread Starter
Dumbest Smart Person
 
Join Date: Jan 2013
Location: DFW Texas
Posts: 434
View RobinDobbie's Photo Album My Photos
Quote:
Originally Posted by Dave Paine View Post
Welcome to the forum, and most folks do post their introduction in the Introductions forum. What a concept.

The start of the cut is good, since the blade has not had chance to be deflected.

By the end of the cut, the blade looks like it is being deflected.

Circular saw blades are thin, to minimize the power required by the saw. Thin also means potential for the wood pushing the blade.

I would make this cut on a table saw with a full kerf blade - 1/8th in.

You likely do not have a table saw.

So plan "B" is to make the cut wide with the circular saw, then create a bevel shimmy for a router and finish with a straight cut bit to get a consistent angle and decent face.
Thanks for the reply! I do have a table saw, but the table isn't wide enough for the pieces I have.

Can I just get a thicker blade for this circular saw? There's plenty of power for this soft pine plywood.

Quote:
Originally Posted by wood8671 View Post
Friction? Is the blade new or 10 years old?
The stricks can be fixed with tape on the bottom of the shoe, better yet put cardboard between the saw and your material
The friction is between the board and the bottom of the saw. The blade on the new saw has been used a couple of times, and the blade on the old saw just a few times, as well.

Thanks for the tape/cardboard suggestion. I can't believe I didn't think of that myself!
RobinDobbie is offline  
post #5 of 18 Old 01-30-2013, 10:19 PM Thread Starter
Dumbest Smart Person
 
Join Date: Jan 2013
Location: DFW Texas
Posts: 434
View RobinDobbie's Photo Album My Photos
Well, I went back out and tried to remedy the situation with what's on hand. I kept the guide at the start position the same, but moved the end position 1/16th of an inch over to finish the angle on that end. Somehow, the end is now 1/8th inch narrower instead of 1/16th narrower. Ugh.
RobinDobbie is offline  
post #6 of 18 Old 01-31-2013, 08:20 AM
Member
 
Join Date: Jan 2013
Location: Southeast Kansas
Posts: 45
View wood8671's Photo Album My Photos
Making bevel cuts with a circular saw is tough, clamps have to be very tight until you get comfortable with it. Go slow with steady pressure and put the straight edge and the shoe on the bulk of the material.
wood8671 is offline  
post #7 of 18 Old 01-31-2013, 08:48 AM
Senior Member
 
Join Date: Aug 2010
Location: Maine
Posts: 1,932
View Hammer1's Photo Album My Photos
The base on many portable circular saws are not parallel with the blade. If it's not in line, it won't follow a straight edge. The blade guard on the saw will add resistance as it's pushed open. When making critical cuts, you hold it open by hand until the saw is engaged in the work. There are some types of tape that are slippery, similar to electricians tape but with better adhesive and wider that you can place on the saw base to eliminate marking. You need a good blade with finer teeth for crosscut work. The action of a circular saw will cause some splintering on the top side of the work. You can run some masking tape where you want to cut to help reduce the tear out.

Make sure the cord is free and out of the way, don't stand on it, LOL. Never back up with a circular saw, never place a hand behind one as you are cutting. Make sure the work is clamped so it can't move, use two hands on the saw. Cut the work a little longer, 1", then make your bevel cuts.
Hammer1 is offline  
post #8 of 18 Old 01-31-2013, 09:04 AM
Senior Member
 
Join Date: Jan 2010
Location: NW Pa
Posts: 2,951
View TimPa's Photo Album My Photos
circular saws are great, however not a cabinetmakers first choice. angle cuts are difficult at best. for best results: 1. try not to make the first cut the final cut, cut it long then just trim to the final line to minimize blade deflection. 2. use a good straight edge guide 3. aplly good solid down pressure on the saw to keep the saw level throught the cut. 4. you can score the cut line on the plywood to miminimze tearout. 5. go slow enough to let the saw make the cut as well as it can. 6. new saw/blade and you're set.
TimPa is offline  
post #9 of 18 Old 01-31-2013, 09:58 AM Thread Starter
Dumbest Smart Person
 
Join Date: Jan 2013
Location: DFW Texas
Posts: 434
View RobinDobbie's Photo Album My Photos
Quote:
Originally Posted by wood8671 View Post
Making bevel cuts with a circular saw is tough, clamps have to be very tight until you get comfortable with it. Go slow with steady pressure and put the straight edge and the shoe on the bulk of the material.
It sure is! Yes, my clamps were on tighter than a hipster's pants.

How slow? Is an inch per second a good speed?

And yes, I always keep the most material on the left.

Quote:
Originally Posted by Hammer1 View Post
The base on many portable circular saws are not parallel with the blade. If it's not in line, it won't follow a straight edge. The blade guard on the saw will add resistance as it's pushed open. When making critical cuts, you hold it open by hand until the saw is engaged in the work. There are some types of tape that are slippery, similar to electricians tape but with better adhesive and wider that you can place on the saw base to eliminate marking. You need a good blade with finer teeth for crosscut work. The action of a circular saw will cause some splintering on the top side of the work. You can run some masking tape where you want to cut to help reduce the tear out.

Make sure the cord is free and out of the way, don't stand on it, LOL. Never back up with a circular saw, never place a hand behind one as you are cutting. Make sure the work is clamped so it can't move, use two hands on the saw. Cut the work a little longer, 1", then make your bevel cuts.
I didn't think of the blade not being perfectly parallel. I just figured it would be, at least with the new $120 saw(hey, I could have gotten a $49 saw).

I hold the guard open every time, usually the whole cut because I forget to let it go!

I make sure the cord isn't a problem. It's almost always got enough slack.

Not as worried about splinters as I should be. My next project will feature naked wood, so I'd do well to stop the splinters now. Thanks for the tip!

I was afraid someone say I need to cut the wood longer! I really should have. But, I'm at the very edge, here! At least I know what to do next time.

Quote:
Originally Posted by TimPa View Post
circular saws are great, however not a cabinetmakers first choice. angle cuts are difficult at best. for best results: 1. try not to make the first cut the final cut, cut it long then just trim to the final line to minimize blade deflection. 2. use a good straight edge guide 3. aplly good solid down pressure on the saw to keep the saw level throught the cut. 4. you can score the cut line on the plywood to miminimze tearout. 5. go slow enough to let the saw make the cut as well as it can. 6. new saw/blade and you're set.
Thanks for the tips! I really like the idea of scoring the wood, first. I should probably get a new blade, too. can I get a thicker blade than the thin kerf that comes with the saw?
RobinDobbie is offline  
post #10 of 18 Old 01-31-2013, 11:24 AM
Senior Member
 
Gilgaron's Avatar
 
Join Date: Mar 2012
Location: Central Ohio
Posts: 911
View Gilgaron's Photo Album My Photos
Can you do a straight cut to width and then cut the bevel? You could also do some relief cuts with a small hand saw to help the waste fall away as you go. I find relief cuts especially useful when doing anything tricky with handheld saws like circular or jig saws.
Gilgaron is offline  
post #11 of 18 Old 01-31-2013, 12:14 PM
Senior Member
 
MT Stringer's Avatar
 
Join Date: Jul 2009
Location: Channelview, Tx
Posts: 2,644
View MT Stringer's Photo Album My Photos
I bought a new circular saw a while back and a new blade to go with it. I haven't even put the factory blade on the saw. The blade I bought is a Freud Diablo 7 1/4 inch 60 tooth carbide tipped thin kerf blade.

See it here.

The blade cuts smooth as butter and leaves a smooth cut on the wood. I used it to cut down a solid core door (1 3/4 inch thick).
Also, it was used to cut a table top to it's final dimensins. The top is made out of 1 5/8 inch solid maple 36 x 65 inches. I took diagonal measurements after cutting and the cuts were perfect. Pics below show the table top ready for stain and the final result installed on it's frame.

Good luck. Hope you get your problems worked out. Practice, practice, practice.

Question. How large are your speakers that you can't rip the pieces on a table saw?

Note: I use painters tape to cover the intended cut top and bottom of the board. Helps reduce the possibility of splintering especially on the cross cuts.
Attached Thumbnails
Click image for larger version

Name:	2012-11-19 17.17.10.jpg
Views:	246
Size:	100.8 KB
ID:	61477  

Click image for larger version

Name:	Table1.jpg
Views:	217
Size:	81.1 KB
ID:	61478  


Last edited by MT Stringer; 01-31-2013 at 12:17 PM.
MT Stringer is offline  
post #12 of 18 Old 01-31-2013, 12:21 PM Thread Starter
Dumbest Smart Person
 
Join Date: Jan 2013
Location: DFW Texas
Posts: 434
View RobinDobbie's Photo Album My Photos
How long would a cut need to be to take advantage of relief cuts?

I think the problem I was having last night with the 1/8th missing instead of just 1/16th can be attributed to not having an accurate square. I'm using a Drywall T-Square and I just did a little test. On a 36" board I laid the square down. I drew a quarter of an inch line with a mechanical pencil on both ends of the wood. I then flipped the square over and lined it up with the lines. It wasn't off by much, maybe 1/16th. But, I can see how that could add up around the board.

Are there any accurate long squares?
RobinDobbie is offline  
post #13 of 18 Old 01-31-2013, 12:25 PM Thread Starter
Dumbest Smart Person
 
Join Date: Jan 2013
Location: DFW Texas
Posts: 434
View RobinDobbie's Photo Album My Photos
Quote:
Originally Posted by MT Stringer View Post
I bought a new circular saw a while back and a new blade to go with it. I haven't even put the factory blade on the saw. The blade I bought is a Freud Diablo 7 1/4 inch 60 tooth carbide tipped thin kerf blade.

See it here.

The blade cuts smooth as butter and leaves a smooth cut on the wood. I used it to cut down a solid core door (1 3/4 inch thick).
Also, it was used to cut a table top to it's final dimensins. The top is made out of 1 5/8 inch solid maple 36 x 65 inches. I took diagonal measurements after cutting and the cuts were perfect. Pics below show the table top ready for stain and the final result installed on it's frame.

Good luck. Hope you get your problems worked out. Practice, practice, practice.

Question. How large are your speakers that you can't rip the pieces on a table saw?

Note: I use painters tape to cover the intended cut top and bottom of the board. Helps reduce the possibility of splintering especially on the cross cuts.
Man, that's beautiful!

I should get a new blade to reduce splinters. But, that's not the core of my problem, I don't think.

My boards are between 8" x 22" and 36" x 36". So, some cuts I could do with the table saw, but not most.

Last edited by RobinDobbie; 01-31-2013 at 12:29 PM.
RobinDobbie is offline  
post #14 of 18 Old 01-31-2013, 01:04 PM
Senior Member
 
MT Stringer's Avatar
 
Join Date: Jul 2009
Location: Channelview, Tx
Posts: 2,644
View MT Stringer's Photo Album My Photos
@Robbin. When I use a circular saw to cut a board, I carefully measure the width on both ends of the board to determine where the cut is to be made. It is easy enough to use which ever side of the board is straight. Measure over to the width desired and mark it. Do the same on the other end. I use a tape measure or folding ruler I have had for decades.

Then I set up my guide for the saw to follow. I have a metal guide that has a piece of 1/4 inch plywood attached to the bottom side. Originally, I made it wider that the saw, then ran the saw along the guide which made it the exact width of the blade to edge of the daw. Then simply line up the edge of the guide with your marks, clamp and run the saw along the guide. It should come out prfect if...you run the saw along the guide and don't let it wander.

I guess the drawback is if you use it to cut an angle, the guide would probably not be useable for future 90 deg rips.

Here is a
how to make a guide for your saw.
MT Stringer is offline  
post #15 of 18 Old 01-31-2013, 01:40 PM Thread Starter
Dumbest Smart Person
 
Join Date: Jan 2013
Location: DFW Texas
Posts: 434
View RobinDobbie's Photo Album My Photos
That sounds like the best way to cut. I'll just use the square as a straight edge and make the line by measuring and marking from the opposite edge on both ends.

I'll check out that vid on how to make a guide in a bit. Thanks for the link!

I just checked my circular saw blade's perpendicularity with the base, and the front of the blade is 1/16th off to the right. I guess that would explain last night's results. The damn thing can't even be adjusted, from what I can see. What circular saw should I get?
RobinDobbie is offline  
post #16 of 18 Old 01-31-2013, 01:58 PM
Senior junior member
 
Woodwart's Avatar
 
Join Date: Dec 2012
Location: Southern Ontario
Posts: 546
View Woodwart's Photo Album My Photos
OH, never mind. I replied before I read the whole thread...

Last edited by Woodwart; 01-31-2013 at 02:01 PM.
Woodwart is offline  
post #17 of 18 Old 01-31-2013, 08:01 PM Thread Starter
Dumbest Smart Person
 
Join Date: Jan 2013
Location: DFW Texas
Posts: 434
View RobinDobbie's Photo Album My Photos
MT Stringer, I bought the blade you linked to and a new square. It's only 24" long, but I guess that's enough? To test it, I lined the short end up to a known flat board and drew a line all the way down. Flipped it over and the line still lined up.

What's the best way to square a board longer than 24"?
RobinDobbie is offline  
post #18 of 18 Old 03-06-2013, 10:52 PM
Junior Member
 
Join Date: Feb 2013
Posts: 18
View Gone Wood'n's Photo Album My Photos
Festool has a really AWSOME circular saw with a straight edge guide you can clamp down. bit of pocket book gouging but if you plan to cut lots with such a tool this is the perfect one to get. look them up on their website and watch the videos and look at the reviews. It's a professional tool for those that are but if you're wanting to be where you wish to be you've got to have such kinds of tools that have solid tallerances to give you great cuts.
Gone Wood'n is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Woodworking Talk - Woodworkers Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Circular Saw Question: Single Pass Cuts or Multiple Pass Cuts? Wood4Brains Power Tools & Machinery 5 08-06-2012 10:51 PM
Two table saws = drastically different ply cuts? renovatio Power Tools & Machinery 15 07-09-2011 01:27 AM
Steep angle miter cuts byrdhouschic Tips, Tricks, & Homemade Jigs 6 10-14-2010 08:35 AM
Help? Circular Saws arguezoam General Woodworking Discussion 2 03-01-2010 06:20 PM
Please help with angle cuts for crown on columns RHoffbauer Trim Carpentry & Built-Ins 7 10-16-2008 07:51 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome