Bit problem - using spiral bit in a table

[Matt]

I have 3 spiral router bits that are (supposed to be) made of carbide.
They have 8 cutters - on the end and along the body.
They do great flat bottoming and very clean cuts.
I have used 2 of them in my plunge router - and they work great.

Last night I tried the 3rd one in my router table (same router, PC690) - and it
didn't work - It burned not cut - and I was working on pine.

The cutters are cutters look sharp and feel sharp to the touch
The router is turning the right way
I did take the protective goop off of it first (actually long ago)

It is a 1/4" shank , and a 3/8" cutter

This is the first time I've used this particular bit

Is there something about spiral bits that they need to get plunged for them
to work correctly?
It doesn't make sense to me, but I thought I would bring this question to
the collective wisdom for some insight.

Matt

[reible]

I personal haven't seen a router bit like you describe but my guess would be you were not feeding fast enough, or trying to take off to much material at one time. That's a general comment on any bit that burns.

Could you provide us with a picture of these bits? Or if you ordered them on-line a url so we can see? They sound interesting.

Ed

[BobandRick]

Originally Posted by Matt

I have 3 spiral router bits that are (supposed to be) made of carbide.
They have 8 cutters - on the end and along the body.
They do great flat bottoming and very clean cuts.
I have used 2 of them in my plunge router - and they work great.

Last night I tried the 3rd one in my router table (same router, PC690) - and it
didn't work - It burned not cut - and I was working on pine.

The cutters are cutters look sharp and feel sharp to the touch
The router is turning the right way
I did take the protective goop off of it first (actually long ago)

It is a 1/4" shank , and a 3/8" cutter

This is the first time I've used this particular bit

Is there something about spiral bits that they need to get plunged for them
to work correctly?
It doesn't make sense to me, but I thought I would bring this question to
the collective wisdom for some insight.

Matt

The 1/4" shank with a 3/8" cutter leads me to think this is not Carbide. Question: Does the cutter look the same as the other ones that work? This might this be an end mill used in metal cutting? Can you post a picture?

[Mike]

Rick hit it on the first try. With 8 cutting edges on a bit this small it is an end mill. The bit is designed for cutting metal in very small amounts. It wont clear chips quickly and as a result you get heat build up. Perhaps the reason you got away with using the other two bits was moisture content of the wood?

[Matt]

I appreciate your replies

I described the bit incorrectly
The 1/4 " has 3 cutting edges
the 3/8 has 6
the 1/2 has 8 - this is the one that I looked at as it was not in the router and was handy

I bought the two larger bits at the Toronto Wood show in Feb 04 from 'who knows', a seller from BC. The 1/4 bit I bought at Lee Valley

I have posted the pictures of the 3/8 bit - (pardon the non Oak Park table)

Also, the depth of cut attempted was about 1/8", and I was pushing slowly to start.

Prior to using this bit, I used 5/16" 2-flute with 1/8" depth but the groove was too narrow and I would have to adjust the fence and do another cut to bring the width to 3/8 - which is when I remembered I had these spiral bits.

I am making a miniture sea chest. The sides are to be joined in dados in corner posts.
The corner posts are 3/4" square.
The sides are 'planks' that are 2" wide and 3/8 thick.
The box size is 18" by 12," 6" high before the curved top is on.

I just realized that I am posting this out of sequence.
Hopefully they pictuers are not too fuzzy.

Matt