External corners for skirting

[Jupiter01]

This is probably me being a numpty but would like your input on the following please.
I have an external corner which when measured with a try square is definitely less than 90 degrees.

I then followed these steps to bisect the angle using my bevel:

Because the angle was clearly less than 90 degrees, I expected to find that I need to set my mitre cuts to less then 45 degrees. When I put my bevel (after bisecting the angle) on my Makita MLS 100, its apparent that the angle needs to be greater than 45 degrees as the bevel angle isn't satisfied by the 45 degree (maximum) angle of my saw.

I hope this makes sense and someone can point out what I am doing wrong!
Thanks in advance

 

[Ryler]

If the ex angle is less than 90 then the miter cut is greater then 45.

 

[Jupiter01]

but...
if the angle is lets say, 85 degrees i.e. less than 90, should the angle not be set at 42.5?

 

[rsgaz]

If you are looking at the skirting from above...(ignore imaginary red lines for now)

And the wall is 85°, then the rest of the angle needs to add up to 360, to make a circle, so...

(360-85)÷2=137.5°

We just need to knock off 90, to find angle X, which makes it 47.5°

 

[Jupiter01]

Can this problem also be fixed by cutting the angle at 45 and then planing the inside part of the mitre?

 

[Deleted member 174758]

Yes. In the days before electric mitre saws (maybe 3 centuries up until.the 1980s) that's what they did

 

[Jupiter01]

LoL
But I still have that problem with a 21st century Makita Saw that doesn’t cut more than 45 degrees. Is that uncommon?

 

[conny]

Most mitre saws will only cut up to 45degrees but one way to combat this is to reverse the wood so you feed it from the opposite side.
Long time since I did it but I think you also have to flip it over.
Try some scrap pieces to see if it works the way you need it to.

 

[Deleted member 174758]

LoL
But I still have that problem with a 21st century Makita Saw that doesn’t cut more than 45 degrees. Is that uncommon?

OK, well the all singing, all dancing sliding double bevel laser hoopla saws can go up to about 48° (and sometimes as much as 50°) on the bevel cuts, but even that isn't going to be enough in some cases. What i tend to do is stick a 3 to 10mm packer onto the outboard edge of the saw bed to lift the material a litle, giving me a few more degrees of bevel. A bit hit and miss, but gets me out of a hole at times. Don't try this unless you are an experienced mitre saw user