# Router Bit ID



## chefkeith (Nov 28, 2013)

Hi, new to forum. I recently bought a used router (Bosch 1617 EVS) at a pawn shop and it came with an insert flush trim router bit that I'm having trouble identifying. Has anyone here seen this bit before or know what brand it could be? 

I reversed the knife already, so I have a new sharp edge right now, but I'd like to know where to get new knives for it, if I ever need them. Thanks. 


The blade is held in place with a wedge that has 4 screws. 









This uses 4mm x 14mm hex socket countersunk screws. 









Shank Diameter : 1/2"









Bearing Diameter: 3/4"









Overall Length : 4 - 3/32










Knife Length : 1 - 31/32 (50mm) 









The Insert Knife seems to match the CMT 790.500.01 shape and dimensions (50mm L, 5.5MM Width, 1.1MM thick), but I've only seen drawings of that knife, no actual pictures. I could order those knives to see if they work, but I hate to take a shot in the dark like that. I haven't found a similar wedge with 4 screw holes by CMT, which is why I'm skeptical and here asking about this.


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## DaninVan (Jan 1, 2012)

I share your doubt, Keith; does the bit shank have a CMT logo engraved on it?
I guess the definitive answer on CMT would be from them...

[email protected]

Good luck!


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## Cherryville Chuck (Sep 28, 2010)

I know that a lot of them are very standard sizes, for example 12mm x 12mm x 1.5mm, but that doesn't necessarily mean that they all are. I found some suppliers by Googling insert knives I think it was. Somebody who specializes in supplying insert knives should have a good idea I would think. You might have to try a few variations like "router bit insert knife" to find the ones that are meant for woodworking instead of metal working.


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## chefkeith (Nov 28, 2013)

DaninVan said:


> I share your doubt, Keith; does the bit shank have a CMT logo engraved on it?
> I guess the definitive answer on CMT would be from them...
> 
> [email protected]
> ...


No logo or engraving of any kind. I was thinking it might be an OEM or custom bit.


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## MAFoElffen (Jun 8, 2012)

Expand your search...

CMT Industrial Router bits include straight router bits with indexable knives (3/4") such as the 352B series, but with that size they use 3.5mm screws... and use only 2 screws each knife.

Globus has Industrial straight router bits with indexable knives, but use 2 3mm screws each knife.

Dimar industrial straight template bits with indexable knives (3/4") use 4mm screws, but only use 3 screws each knife. 

-- But those are all 2-flute bits where yours looks to be single flute?

Amana Industrial has these type bits, but their industrial site is down so I can't check there...

In CNC and Industrial tooling, this seems to be a new, common sense direction in tooling design. Initial cost is higher, but long-term costs are lower. Even available in panel raising profiles.

The key right now is it's an "industrial tooling" kind of thing so far, so ID is going to be through industrial tooling channels. A quick ID tip might be to contact a pro sharpening shop and let them do the homework to ID the carbide inserts.


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## chefkeith (Nov 28, 2013)

I just sent CMT an email. Thanks.


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## jw2170 (Jan 24, 2008)

Even the Carbi-Tool range only have 2 and 3 hole cutters.

replaceable insert bits


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## chefkeith (Nov 28, 2013)

MAFoElffen said:


> Expand your search...
> 
> -- But those are all 2-flute bits where yours looks to be single flute?
> 
> The key right now is it's an "industrial tooling" kind of thing so far, so ID is going to be through industrial tooling channels. A quick ID tip might be to contact a pro sharpening shop and let them do the homework to ID the carbide inserts.


Yes, it's a single flute. Thanks for advice.


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## MAFoElffen (Jun 8, 2012)

I believe I found the carbide inserts for you.

Nap Gladu, Standard Inserts, Catalog page number 76, US Part Number "TJ241Q".

This is the insert. (Look at attached picture). Measurements of inserts are in metric. Minimum order, 10 inserts.


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## chefkeith (Nov 28, 2013)

I just got an email back from CMT. Apparently, this is a CMT bit, but it is quite old, which they no longer produce. They have since updated the design and construction method. However the knives are still available for purchase, and indeed are the CMT 790.500.01 that I mentioned in my initial post. They are available at both AceToolOnline and Amazon dot com. So I got my answer. 

Many thanks for suggestion/link to email them. Thanks to everyone for all the effort and help.


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## MAFoElffen (Jun 8, 2012)

chefkeith said:


> I just got an email back from CMT. Apparently, this is a CMT bit, but it is quite old, which they no longer produce. They have since updated the design and construction method. However the knives are still available for purchase, and indeed are the CMT 790.500.01 that I mentioned in my initial post. They are available at both AceToolOnline and Amazon dot com. So I got my answer.
> 
> Many thanks for suggestion/link to email them. Thanks to everyone for all the effort and help.


Which is the same spec's as the one I found... 

So it is a standard carbide insert size and you have some options on how and where you get it. More importantly, is that since it is a standard carbide knife size... The knife inserts themselves aren't going to be phased out and go away soon.


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## Cherryville Chuck (Sep 28, 2010)

I picked up some good deals on an Amana and some Leitz RC bits on ebay not long ago and the directions for all of them say to make sure you clean the bits well when you change or rotate knives. I searched for suppliers to make sure I could get knives for them and this is one I came up with that had reasonable prices. Carbide Insert Knives, ICK, Turn-able


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## jschaben (Jun 21, 2009)

Cherryville Chuck said:


> I picked up some good deals on an Amana and some Leitz RC bits on ebay not long ago and the directions for all of them say to make sure you clean the bits well when you change or rotate knives. I searched for suppliers to make sure I could get knives for them and this is one I came up with that had reasonable prices. Carbide Insert Knives, ICK, Turn-able


Thanks for that info Chuck - I've got a Amana that is about due for new knives and I have been loathe to buy 10 of 'em at ~$6 per.:dance3:


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## Cherryville Chuck (Sep 28, 2010)

You're welcome John. Like everything else there are a wide variety of prices and probably a wide variety of quality too but they are certainly worth a try. Let me how they work out if you get some. I haven't needed to buy any yet.


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## jschaben (Jun 21, 2009)

Cherryville Chuck said:


> You're welcome John. Like everything else there are a wide variety of prices and probably a wide variety of quality too but they are certainly worth a try. Let me how they work out if you get some. I haven't needed to buy any yet.


Hi Chuck - Will do, not sure when though. This year has been brutal with home improvement stuff. 
I did read something awhile back that the insert bits can use a harder grade carbide because they don't need to go through the brazing process. Don't recall just where I read that though, I do know this one has run me quite a good long time including a bunch of MDF in the mix.


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## Cherryville Chuck (Sep 28, 2010)

Home renos kept me from using any of the ones I bought too and now it's too cold here. Next summer (I seem to say that a lot).


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