Project by Maveric777 |
posted 03-09-2010 01:52 AM |
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15 comments |

I threw this together this weekend trying to solve my dilemma of cutting perfectly mitered corners for boxes. It was a hard fought battle, but I think I may have it lined up right…. Ummm Maybe.

I went off the principle that so long as the wood is flat and you cut your angle… Even if it wasn’t a perfect 45 it will still come to a 90. So for instance if the blade is actually a 44 deg cut on the left side of the blade you can flip the lumber over and cut the second piece on the right side and it should be 46. Add the two together and you will have a 90.

Now that seemed to work all fine and dandy in principle, but after tearing into some pretty cherry I found something wasn’t right. Actually is was far from right. After rechecking things I found I took ever precautions except making sure the back fence (rest) was square to the blade path…. Rookie mistake.

Well I removed the back rest and had to pick up something to make a shim (to sit in the blade path… Thanks again Curtis for the help over at Ace) and some plastic squares. I aligned and secured it (the second time) pretty much dead on….. Or so I thought.

I am still not sure if I need to make a few more adjustments, or if the cherry I was cutting was slightly bowed (I’m thinking this was a major… yet another rookie mistake), or I failed on glue up. I am leaning towards the later two. So now i know to make sure I plain everything down before hand. Secondly…. Learn the tricks to gluing up mitered corners….lol

Oh the learning curve….

Thanks for checking it out.

-- Dan ~ Texarkana, Tx.

## 15 comments so far

degoose

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7238 posts in 3475 days

#1 posted 03-09-2010 02:15 AM

Every mistake is a lesson learnt.

-- Don't drink and use power tools @ lasercreationsbylarry.com.au

shredkeenan

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#2 posted 03-09-2010 02:55 AM

The problem is that your assumption is false – two halves of a board cut in that manner will NOT make a 90 unless the cut angle is EXACTLY 45 degrees.

Maveric777

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2693 posts in 3196 days

#3 posted 03-09-2010 03:06 AM

45+45=90

44+46=90

43+47=90

etc…

I feel pretty confident on my assumptions on that part…

-- Dan ~ Texarkana, Tx.

Beginningwoodworker

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#4 posted 03-09-2010 03:18 AM

Nice looking miter slide.

Dennis Fletcher

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#5 posted 03-09-2010 03:25 AM

I think what he means is that it may make 90 degrees, math wise, but unless you cut true 45’s on all sides, your box, frame, etc., won’t come out with 90 degree angles.

If you do 44+46 on the right side, then you have an un-square angle and you next angle in line will not come out right. This is true, especially when trimming out doors/windows.

-- http://www.ahomespecialist.net, Making design and application one. †

bigike

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#6 posted 03-09-2010 03:36 AM

good job!

-- Ike, Big Daddies Woodshop, http://www.icombadaniels@yahoo.com

rsmith71

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#7 posted 03-09-2010 03:38 AM

Your assumptions are right, Maveric. 44+46=90. Your corners will be square. However, by using odd angles to get to 90 degrees you’ll have issues with lining up the insides and outsides of the pieces in the corner. I’m not real good at explaining it but when you’re mitering 2 pieces of different widths, you don’t cut both at 45. to get it to line up, one may be at 30 and the other at 60, but the corner will come out square.

-- Robert - Haven Wood Crafts

Dennis Fletcher

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467 posts in 3174 days

#8 posted 03-09-2010 04:02 AM

Maveric777, I forgot to mention, this is a great project. It looks well built and well thought out.

rsmith is right, when using different thicknesses, you have different angles to make up 90, but I have found that if everything is the same thickness, it needs to be pretty close to two 45’s to get every angle square. I have never tried your method, however, so let me know if it does end up working, as that would make things a bit easier for me.

-- http://www.ahomespecialist.net, Making design and application one. †

shredkeenan

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61 posts in 3577 days

#9 posted 03-09-2010 04:13 AM

Come on guys this is basics…cutting a board like that will yield two pieces with the exact same bevel angle, NOT complementary angles.

See the attached image…the cut pieces will only give you a square corner if X is 45 degrees.

mancave

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#10 posted 03-09-2010 04:41 AM

Shred is right. If you were to stand the second cut on end (90 degrees to first cut) you could get a 90 degree corner, BUT the mitered cut lengths will be different lengths making for a bad fit, try it with going to a 39/60 degree cut to prove the point. It will then be easy to see the problem.

ScienceNerd

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#11 posted 03-09-2010 05:37 AM

Hi, Dan. Shred nailed it on this one (good fig, too). I think you were thinking something akin to what we use for picture frames (good example here: http://lumberjocks.com/projects/28019 ).

What you need is something more ‘vertical’. Think of a 90-degree “v” sitting on-point your sled. Not sure if your blade depth will be sufficient for something like this, but it’s what would be required for the complementary angles to work.

Or just fiddle with the blade angle until it’s right. :)

Maveric777

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#12 posted 03-09-2010 05:39 AM

OK… I admit I missed a major detail on this…. I call the left side of the blade cut number 1… the right side of the blade cut number two. On the box I just put together the front and back I cut them both on side number 1. On the sides I cut them both on number two. So where the front meets the side I will have a combined angle of 90 deg.

I forgot to mention that… Sorry about the mix up… But it does in fact come to 90…

My fear was trying to nail a 100% 90 deg angle. So my theory is I get the cut as absolutely close to 45 as I can and keep the method of cutting the fronts and sides on the proper sides of the blade… Well I can be .5 deg off and I will still come up with my 90..

I hope I made better sense this time. I’m not the best at describing things…lol

-- Dan ~ Texarkana, Tx.

1yeldud1

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#13 posted 08-10-2010 05:33 AM

My question is how do you get the blade tipped over on exactly 45 degrees every time you set up this fixture ?? I chose to the style of fixture that leaves the blade square to the table and rotates the work on a 45 degree angle – not that type is better just what i decided to build.

Maveric777

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2693 posts in 3196 days

#14 posted 08-10-2010 12:49 PM

I use one of these. Takes all the guess work out of the angle….

-- Dan ~ Texarkana, Tx.

1yeldud1

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301 posts in 3162 days

#15 posted 08-10-2010 08:56 PM

LOL – kind of like a “GPS” for the table saw ?????

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