# Router bits that allow another part of the bit to be screwed into it.



## eleanor (Jun 3, 2011)

I have several older router bits that have a threaded shank that allows another part of the bit to be screwed into it. What is the purpose of this?


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## bobj3 (Jan 17, 2006)

Hi Harry

I think you are talking about this type.
It's the old way of using the router bits, at one time you only had 3 or 4 arbors and many cutters, it's best to put them in a box and not use them they will burn the stock in a heart beat..most are HSS steel...

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eleanor said:


> I have several older router bits that have a threaded shank that allows another part of the bit to be screwed into it. What is the purpose of this?


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## Mike (Nov 22, 2004)

Harry, most of these screw together bits were Craftsman. I have a couple that are carbide tipped and useable but they went into my scrap can. (Can for recycling, not garbage) I suggest you do the same; it is way too easy to assemble these bits the wrong way. The idea was cost savings but it faded out quickly.


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## Cherryville Chuck (Sep 28, 2010)

The arbor threaded into one end of the bit and a pilot threaded into the other side. As pointed out, they were best at burning wood. The solid pilots would wear a hole into your piece if fed too slowly or if they hit a soft spot. They are old and poor technology.


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## Phil P (Jul 25, 2010)

Interestingly Her-Saf still make them for use with their special-purpose machines. From a manufacturer's perspective I suppose it makes the cutter heads a one size fits all solution

Regards

Phil


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## Mike (Nov 22, 2004)

Phil, as you pointed out the Her-Saf bits are specialty bits for production and a far cry from the bits that saturated the market. The difference in quality and cost is apparent by looking at the bits.


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## jw2170 (Jan 24, 2008)

eleanor said:


> I have several older router bits that have a threaded shank that allows another part of the bit to be screwed into it. What is the purpose of this?



Welcome to the router forum, Harry

Thank you for joining us


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## Phil P (Jul 25, 2010)

Mike said:


> Phil, as you pointed out the Her-Saf bits are specialty bits for production and a far cry from the bits that saturated the market..


True enough, Mike. I can't recall ever seeing many threaded arbors here in the UK, possibly because until the mid 1970s routers were a relative rarity for home woodworkers. I can understand the Her-Saf heads - the head can be swapped-out without the need to recalibrate the specialist machine in which the router motor is mounted (in the same way that replaceable tip TCT cutters have become widely used in the woodworking CNC arena) - but I wouln't see much advantage in that for light DIY use

Regards

Phil


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## bobj3 (Jan 17, 2006)

for the DIY users
Screw on cutters

Woodhaven - Woodworking Tools, Supply & Equipment

http://woodhaven.com/Woodhaven-13550-12-diameter-screwon-cutter/M/B002YOKNI4.htm
http://woodhaven.com/Woodhaven-13572-2332-diameter-screwon-cutter/M/B002YOHUH6.htm
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## jschaben (Jun 21, 2009)

Amana has a line of those things, here's a US source:
EZ-Change Replaceable Head Router Bits -Toolstoday.com- Industrial Quality Replaceable Head Router Bits (Replaces Ocemco)
I'm under the impression Amana is mfg in Israel. If that's true, I would think they would be available UK.


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## Phil P (Jul 25, 2010)

jschaben said:


> I'm under the impression Amana is mfg in Israel. If that's true, I would think they would be available UK.


You'd have thought so, wouldn't you, especially as Trend in the UK buy a lot of stuff from the same places in Israel (if you're in the UK a good reason to search Trend's site if you ever want anything by Amana) - but they don't do the replaceable head stuff

Regards

Phil


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## istracpsboss (Sep 14, 2008)

Actually, Trend do list some bits with an IIRC 10mm thread. I spotted them in their catalogue yesterday. I'll try to remember to look it out when I get home. They are made for a specific machine.

Cheers

Peter


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## Phil P (Jul 25, 2010)

istracpsboss said:


> Actually, Trend do list some bits with an IIRC 10mm thread. I spotted them in their catalogue yesterday. I'll try to remember to look it out when I get home. They are made for a specific machine.


Yes, possibly the Brookman dovetailer (although I thought they were 3/8in BSW male threaded). The only other tools I can think of were the Elu MOF11 amd MOF31 which require a cutter with an hole at the top of the shank and are threaded internally. Trend were the original British importers of Elu routers as far back as 1959 (according to Jim Phillips' book)

Regards

Phil

Correction. Brookman cutters are 3/8in BSF. See here


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## bobj3 (Jan 17, 2006)

Hi

Like Mike said they are very old tech stuff in the states, always with 1/4" shanks from Craftsman, always in HSS...some came with slotted screws and some came with hex nuts to keep the cutter in place and some just screw on the arbor, I think and have a full set in the shop somewhere but have not used them for many years  I see them now and than on eBay...for sale.


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## istracpsboss (Sep 14, 2008)

Found them again. Page 77 in the current Trend catalogue, bottom right. Threaded internally M10 x 1.5, described as Rotox cutters, intended for uPVC and ally.

Cheers

Peter


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## Phil P (Jul 25, 2010)

istracpsboss said:


> Found them again. Page 77 in the current Trend catalogue, bottom right. Threaded internally M10 x 1.5, described as Rotox cutters, intended for uPVC and ally.


Hi Peter

They're the type designed to be used on the older Elu routers, especially on Elu's alumnium/PVCu window machinery (still manufactured albeit under the name "Elumatec" these days - they've also dropped the high speed router motors of yore). Scheer still use M10 x 1.5 threads on some of their routers, e.g. the HM4, HM9 and HM14, whilst others like the HM17 come with an adaptor to take M10 x 1.5 (the larger routers use M16). Scheer routers are used in some very specialised equipment like their stair string routers and their FG308 curved handrail machine 

If nobody has ever heard of Rotox, they're German and make PVCu machinery for windows and doors including these

Regards

Phil


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## istracpsboss (Sep 14, 2008)

Thanks Phil. Some interesting links there.

Cheers

Peter


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