# Two sizes of lock miter bits. Which do I need?



## dawziecat (Dec 8, 2009)

I see lock miter bits with a depth of cut of 1-1/8" and 3/4".

I will invariably be using them to work 3/4" stock. Does that mean the obvious, i.e., I need the bit with a depth of cut of 3/4"?

Or would that actually be for use with 1/2" stock?


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## harrysin (Jan 15, 2007)

Terry, there are three common size lock mitre bits which cover the following joint thickness;

35mm dia. covers 12 to 16mm
44mm dia. covers 14 to 19mm
70mm dia. covers 19 to 28mm

I would suggest the largest one for 3/4" stock and this would I think only be available in 1/2" shank, the other two in 1/4" and 1/2".
This shot shows 3/4" material and a 44mm cutter, as you can see, it only just covers the joint.


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## dawziecat (Dec 8, 2009)

Thank you, Harry.
I will order the larger one then . . . in this case advertised as 2-3/4" (67mm) diameter with depth of cut 1-1/8"(27.5mm) for my 3/4" (18mm) stock.

No doubt this is the 70mm one you mention.


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## jlord (Nov 16, 2009)

Sommerfeld tools carry 2 size bits. A lock miter bit & a baby lock miter bit. When machining stock one piece is run vertically while the other is run horizontally.

The 45* lock miter is suggested for stock that is 3/4" to 1-1/8" thick.
# Cutting Diameter 2 3/4"
# Cutting Length 1 1/4"
# Max. Joint thickness 1 1/8"
# Min. Joint thickness 3/4"
# Shank Diameter 1/2" 
45* Lock Miter Bit 2- 3/4CD,1 -1/4CL,1- 1/8TH,1/2SH-Sommerfeld's Tools For Wood


Use the Baby Lock Miter Bit with stock from 3/8" to 3/4" thick. Build boxes, frames, beams, face-frame corners and many other right-angle joints. Maximum safe speed is 16,000 RPM
# Cutting Diameter 2"
# Cutting Length 7/8"
# Max. Joint Thickness 3/4"
# Min. Joint Thickness 3/8"
# Shank Diameter 1/2" 
Baby Lock Miter Bit 2CD,7/8CL,3/4TH,1/2SH-Sommerfeld's Tools For Wood


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## harrysin (Jan 15, 2007)

You're welcome Terry and the 2 3/4" sure is close enough. Just for the record, what we used to call 3/4" is now 19mm, OK, I know that's being pedantic!


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## Mike Wingate (Apr 26, 2009)

I have all 3 sizes but generally use the 2 smallest sized bits.


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## Mike Wingate (Apr 26, 2009)

I have 1 large 1/2" shank MLCS bit and a medium sized 1/2" shank CMT bit, plus a 1/4" shank, small Axminster Perform bit.


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## Mike Wingate (Apr 26, 2009)

Just noticed that MLCS do 3 sizes, but the postage rates have stopped me from buying at the moment. Can you ask your Prez to devalue the $ again?
MLCS lock mitre router bits


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## TwoSkies57 (Feb 23, 2009)

I picked up a vermont american bit from a big box store a while back for 3/4" stock. The bit itself was just a hair shy of true and I ended up having to either plane down my 3/4" stock a hair or just going with 1/2" stock. Aggrivating to say the least...in this case at least, I got what i paid for....


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## TwoSkies57 (Feb 23, 2009)

Mike... *L* I doubt we'll have to ask....


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## Mike Wingate (Apr 26, 2009)

These bits are really critical for wood thickness. I was tempted to buy setup blocks, but made my own, then some more. I have decided to standardize my stock for this bit. The big 2 3/4" bit is a monster, no way would I take off all the wood in 1 pass. I don't think the extraction would cope.


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## bobj3 (Jan 17, 2006)

#5547 3/8" to 1/2" 1-3/8" 1/4"
see video same web page
MLCS lock mitre router bits

http://cgi.ebay.com/1-pc-1-2-Shank-...ViewItemQQptZRouters_Bits?hash=item1e5a19a7e2

http://cgi.ebay.com/1-pc-1-4-Shank-...ViewItemQQptZRouters_Bits?hash=item1e5a21a638

http://cgi.ebay.com/1-pc-1-2-Shank-...ViewItemQQptZRouters_Bits?hash=item20af1d0669

=======


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## jlord (Nov 16, 2009)

bobj3 said:


> #5547 3/8" to 1/2" 1-3/8" 1/4"
> see video same web page
> MLCS lock mitre router bits
> 
> ...


The first two links for the bits on Ebay are very close on cutting depth. The shank size is the big difference between the two.
0.642" - 1/2" shank bit
0.682" - 1/4" shank bit


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## kp91 (Sep 10, 2004)

Mike Wingate said:


> Just noticed that MLCS do 3 sizes, but the postage rates have stopped me from buying at the moment. Can you ask your Prez to devalue the $ again?
> MLCS lock mitre router bits


He's working on it as we speak Mike.....


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