Router bit definitions. US and UK. Dovetail bits.

[pe2dave]

I'm reading about a '1/4" 7.5 degree' dovetail.

Anyone know where those dimensions relate to please?
Might guess its the narrowest neck and the angle neck
to tip?


Dave

 

[gidon]

1/4" = D
7.5 degree = A - 90 degrees

Cheers

Gidon

 

[Steve Maskery]

I would agree with that interpretation, but that must make for a very small shank diameter, wouldn't you say?
S

 

[Slim]

Wealden, do a suitable cutter. 1/4" shank.
Wealden. Part No. T1007 (The very first in the list)

 

[pe2dave]

1/4" = D
7.5 degree = A - 90 degrees

Cheers

Gidon

Thanks Gidon.

Nearly right. Angle is the same, just use the max diameter, not the min!

Dave

 

[gidon]

What's nearly right - sorry don't get it?
Cheers
Gidon

 

[pe2dave]

What's nearly right - sorry don't get it?
Cheers
Gidon

Sorry. My guess was nearly right?
I guessed the neck size, in fact it's the larger diameter
as shown on the figure.

Not many of the UK suppliers seem to provide those sizes
though. CMT do, but others just say '1/4" dovetail'
and leave it at that.

Dave

 

[gidon]

Ok I get you!
What do you need that bit for exactly?
Cheers
Gidon

 

[pe2dave]

What do you need that bit for exactly?
Cheers
Gidon

Not that particular bit. I've invested in an US tool
and the bits are specified in that fashion. I'd never
seen it before... in fact never considered how dovetails
are specified (or under specified it seems in the UK),
hence the question which your diagram nicely answered.

So it was education as much as anything.


Dave

 

[gidon]

Glad you're sorted!
If you really want to get confused try using an (US) Incra jig to cut dovetails with Woodrat (Metric) bits!
Cheers
Gidon

 

[Tom K]

Feeling a bit dense today Is the drawing not to scale? How big is the shaft.

Regards Tom

 

[Jake]

I would agree with that interpretation, but that must make for a very small shank diameter, wouldn't you say?
S

Never seen one, but like a small straight bit, I imagine the 'neck' of the cutter part is smaller than the shaft (unlike in the diagram).

 

[pe2dave]

I would agree with that interpretation, but that must make for a very small shank diameter, wouldn't you say?
S

Never seen one, but like a small straight bit, I imagine the 'neck' of the cutter part is smaller than the shaft (unlike in the diagram).

Sorry, my terms (knowing no other).
I meant the diameter at point 'C' on the diagram;
neck 'cos it's the smaller diameter of the cutting bit.

Dave

 

[Steve Maskery]

I imagine the 'neck' of the cutter part is smaller than the shaft (unlike in the diagram).

Of course it is, it's me being thick
S

 

[motownmartin]

I think This might be what your looking for Dave.

 

[Jake]

Sorry, my terms (knowing no other).

I hadn't noticed you used it too, and I think it is a fine term to use (as I would!)

 

[motownmartin]

I think This might be what your looking for Dave.

Sorry, this should have been a PM

 

[pe2dave]

I think This might be what your looking for Dave.

Yes, from Roger I guess.... I was trying to see how my existing
bits matched up.

Templates need tuning to the bits, which isn't easy.

Dave

 

[motownmartin]

I think This might be what your looking for Dave.

Yes, from Roger I guess.... I was trying to see how my existing
bits matched up.

Templates need tuning to the bits, which isn't easy.

Dave

You're not wrong there, I got in a right muddle trying to set the depth of cut so I bought one of these sets, now it's a doddle