Router bits.

[Peter Hamilton-Scott]

This is probably a generic question but are there any intrinsic advantages using 1/4" over 1/2" bits? Most of my bits are 1/2" but I have a few 1/4" bits but I tend to use the 1/2" equivalents. I don't know if I should get rid of them and standardise exclusively on 1/2" bits? A 1/2" shank almost suggests it is more of a 'grunt' bit than the 1/4". Perhaps the difference is in the efficiency of the cutter itself but does a 1/4" behave much differently than a 1/2" at 22K rpm?

 

[Brice Burrell]

Peter, there's more mass to 1/2"bits and this helps resist chattering (plus they dissipate heat better although this generally is a problem for most uses). The two big issues are safety and smooth chatter free cut. The issue of safety is snapping the shank during hard use, making deep dados in one pass and so on. You're most likely to experience this with all carbide bits like spiral bits, so be careful with them. Chatter is when the bit vibrates making what looks like a series of lines in the cut. Half inch shanks bits can be used much harder less chance of breaking or chatter.

However, I see no reason to replace your 1/4" shanks bits unless you are having problems with chatter. I own and use a ton of 1/4" shank bits. That said the general consensus is 1/2" is better. 

 

 

[joiner1970]

What are peoples thoughts to 1/4" v 8mm bits I just bought a 1010 router and it comes with 1/4" and 8mm collets is it worth going over to 8mm or sticking to 1/4".

I have a big Dewalt 1/2" so that they dont come into it. With the old 1/4" Elu I have had for 15 years or more I just used 1/4" bits I dont know if theres any advantage in using 8mm ones with the new router.

 

[rwdawson]

joiner, Peter,

You might want to check the following thread for a discussion comparing the relative stiffness of different diameter shanks.

http://festoolownersgroup.com/index.php?topic=6910.0

The points made on this thread are all valid; my general rule is that larger shank bits are more desirable, especially for frequent applications.

Richard

 

[AlexThePalex]

There's one simple general rule.

The thicker the shaft, the stronger the bit is.

This has the advantage that it is safer, you can work quicker, and it allows you to use more elaborate profiles.

 

[woodguy7]

One other thing,

All the cutters in my Leigh dovetail set are 8mm so i dont know if any other sets or jigs use only 8mm.

Woodguy.

 

[greg mann]

8mm bits are 1.6 time stiffer than 1/4 inch bits while 1/2 inch bits are 4 times stiffer. Rigidity increases exponentially to the diameter.

 

[Holzhacker]

Speaking of router bits ... can anyone recommend router bits for cutting granite? I got a bunch of granite sink cutouts from a friends job and plan on cutting them down to put under our flower pots. I have a big wet saw so cutting isn't an issue. I'd like to put a nice edge on and sand/puff out. Roman ogee or chamfer maybe. I figure I'd have to use 1/2" shaft which is fine for me. Any recommendations are appreciated.
Thanks, Markus

 

[woodguy7]

Found this on the net.  I don't have any experience with granite but if they sell the cutters then i suppose they must work.  Only thing that would concern me with using a woodworking router is if the granite cutter needs constant water to cool & lubricate.
Maybee someone that has done this will advise you better,

Woodguy.

http://www.diamondtoolstore.com/store/index.php?main_page=index&cPath=7

 

[Notorious T.O.D.]

8mm bits are 1.6 time stiffer than 1/4 inch bits while 1/2 inch bits are 4 times stiffer. Rigidity increases exponentially to the diameter.

Same reason I like 1.25" spindle on my shaper rather than .75" or .5"...  That plus the fact that bigger and heavier cutters cut smoother than smaller lighter cutters....

Best,
Todd

 

[score0matic]

8mm bits are 1.6 time stiffer than 1/4 inch bits while 1/2 inch bits are 4 times stiffer. Rigidity increases exponentially to the diameter.

Greg
This begs the question...."How stiff is stiff enough?"
  I realize that there are many  factors at play.  Bit dia.  collet run out.  rpm. bit sharpness/ cleanliness.

It has been my experience that if the bit is good, and it is smaller than the PC template ring dia. of my OF 1010, I haven't had any real issues with them.

 

[score0matic]

Speaking of router bits ... can anyone recommend router bits for cutting granite? I got a bunch of granite sink cutouts from a friends job and plan on cutting them down to put under our flower pots. I have a big wet saw so cutting isn't an issue. I'd like to put a nice edge on and sand/puff out. Roman ogee or chamfer maybe. I figure I'd have to use 1/2" shaft which is fine for me. Any recommendations are appreciated.
Thanks, Markus

I buy from these guys they have always been good to work with http://www.granitecitytool.com/showcat.cfm?catnum=37&pcatnum=98&keyword1=Router%20and%20Profile%20Bits

You can use a wood router for cutting stone but you need to add a gfi and waterfeed to protect yourself and the bit.....being that many of these bits are more $$$ than even Festool routers it is a good idea to make them last as long as you can.

Craig

 

[Brice Burrell]

8mm bits are 1.6 time stiffer than 1/4 inch bits while 1/2 inch bits are 4 times stiffer. Rigidity increases exponentially to the diameter.

Greg
This begs the question...."How stiff is stiff enough?"
  I realize that there are many  factors at play.  Bit dia.  collet run out.  rpm. bit sharpness/ cleanliness.

It has been my experience that if the bit is good, and it is smaller than the PC template ring dia. of my OF 1010, I haven't had any real issues with them.

I hate to say this because it sort of goes against the consensus but I've found 1/4" shank bits to be fine in most common woodworking applications. Apply a little common sense to how you use 1/4" shank bits and you are unlikely to have a problem with them. 

 

[PeterK]

I agree with Brice. Since getting my OF1010, I have purchased many 1/4" shank bits - mostly Freud. I have had no issues at all using them - no complaints. Sure you can break a shank but using just a minimum of sense, I have not broken any. There is no getting around 1/2" shank bits for large radius stuff of course but the concern with 1/4" is not warranted in my opinion. Now I do wish the 8mm bits were readily available as that is by far the best compromise but very few profiles or designs available here in the US.

 

[joiner1970]

Well here in the UK I should imagine most people use 1/4 " ones obviously for small stuff and 1/2" for say worktop joints etc etc thats why I asked is there any real need for 8mm its a bit of an in between size

 

[Brice Burrell]

Well here in the UK I should imagine most people use 1/4 " ones obviously for small stuff and 1/2" for say worktop joints etc etc thats why I asked is there any real need for 8mm its a bit of an in between size

I say no if you have a router that fits both 1/4" and 1/2" shank bits. If you only have the OF1010 then maybe. The only 8 mm shank bits I own are Festool specialty bits, if they were offered in 1/4" or 1/2" I'd buy they in the Imperial sizes.   

 

[jvsteenb]

It's a bit different on my side of the pond. There's mainly 8mm shank bits, you'd have to look very hard to find any 1/4" shank bits.
Here it's either 8mm or 12mm, and some 1/2" as well. Long ago there used to be some 1/4" and even some 6mm bits, but the 6mm never took off and the 1/4" quickly lost to the 8mm bits.
I haven't had any issues with 8mm shanks being not stiff enough.
Obviously something small diameter  like say a 4mm straight bit won't be the stiffest of all, but there's a couple of companies that make very nice fine-grained solid carbide bits in these sizes.
A 4mm straight bit with a 12mm shank doesn't make much sense in fact, for the radius used to step to the bigger diameter is limited, so the 8mm bit would have less stickout then the 12mm bit, making the 8mm option theoretically stiffer for the same cutting depth.
In large diameter bits the thicker shank is a plus, but I'd rather have a premium quality 8mm bit then a reasonable quality 12mm bit.

My OF1010 won't take 12mm bits, and I hate that. But it makes sense, for the majority of the bits that aren't available in 8mm but are available in 12mm ( or 1/2" ) would take to much power. Large diameter profiling bitsets are nice, but my main interest is in deep fingerjoint bits, edge-glueing bits, drawer-front glueing bits and the likes.

Sadly enough, no decent quality bits of this sort are available in 8mm in my neck of the woods, although it's probably for the best.
The main reason as I see it is the power needed to feed wood in a decent non-burning speed through a bit like that. Only the bigger routers can deliver power like that.
And if you need a bigger router, probably in a router table ( a CMS  in my case ) you would also want the spindle to be more stable, the bearings to have a larger diameter, the whole thing to be more bulky, and the whole system to have a bit more mass, for at the speeds a router is spinning, the mass is a very substantial factor in the dynamic stiffness.

That's where 12mm starts to make sense. The only problem is ( in my case ) that I'm gonna eventually need the OF2200 ..... and if you think Festool is expensive in the USA, try converting 1153 Euro's for the routerset with the accessories in Systainer plus 558 Euro's for the CMS insert - it won't fit my older Basis 5A that carries my OF1010.
1711 Euro's for the complete set. That's roughly 2400 US dollars..... 60+ years after the occupation and they're still looting....... ;-)

Needless to say, it won't be purchased within the next couple of weeks .....

Regards,

Job

 

[greg mann]

I don't think it is a power issue for not using Festool not making the 1010 capable of using 1/2 bits. I think it because the spindle could be too easily abused. The 1010 is designed to robustly handle 8mm bits and they know it will perform for many trouble-free years within that range. Ironically, the MFK700 can also use 8mm bits and that fact is almost universally overlooked when people evaluate that router. Festool has engineered it to handle a significantly more rigid range of tools than any other 'trim' router. Compared to the rest the MFK is a brute. OTOH, the 1010 is designed to be a very handy light router that is a significant step up from any 1/4 only machine. If one wants 1/2 capability they shouldn't bemoan the fact that the 1010 doesn't have it because they would run the risk of abusing the machine. Festool listened when folks said would like 1/2 capacity in the 1010. The 1400 is what Festool believes a 1/2 capacity 1010 should look and perform like.

 

[AlexThePalex]

I don't think it is a power issue for not using Festool not making the 1010 capable of using 1/2 bits.

I think it is, because I haven't seen one single 1/2'' router below 1300 watts.

The 1010 is designed to robustly handle 8mm bits and they know it will perform for many trouble-free years within that range. Ironically, the MFK700 can also use 8mm bits and that fact is almost universally overlooked when people evaluate that router. Festool has engineered it to handle a significantly more rigid range of tools than any other 'trim' router. Compared to the rest the MFK is a brute.

Greg, you're thinking too much 'America only'. Like Job said above, here in Europe we hardly have any 6mm (1/4'') bits. All smallest routers here are designed with 8mm bits in mind. The 1010 is one of the high end 8mm routers since most 8mm routers here go from 650 to 1000 watts power. The average is 800 or 900 watts. My DeWalt router has only 800 watts and it can do anything I want it to. The 1010 with it's 1010 watt power is an absolute beast compared to that.

Now when you talk about the trim router MFK700, that's more average around here, for a trim router. Again, it's designed for the 8mm bits and therefor must be a bit stronger than the trim routers for 1/4'' bits Americans are used to. But here it's just the standard. Hardly anybody uses 1/4'' bits here.

OTOH, the 1010 is designed to be a very handy light router that is a significant step up from any 1/4 only machine.

I more think of it as a significant step up from any other 8mm router since the 1/4'' routers are virtually non-existent over here. With it's 1010 watts it is more powerful than about 95% of the competition. If you look at the 1010's development history, then you'll see a good 10-12 years back there was the Festo OF900 which was later accompanied by the Festo OF1000. And out of that one came the OF1010. Whereas other manufacturers keep making a variety of models next to each other to fit different cost lines, I think Festool just concentrated on one 8mm model which they kept on making better and more powerful simply because they could.

If one wants 1/2 capability they shouldn't bemoan the fact that the 1010 doesn't have it because they would run the risk of abusing the machine. Festool listened when folks said would like 1/2 capacity in the 1010. The 1400 is what Festool believes a 1/2 capacity 1010 should look and perform like.

Yup.

 

[joiner1970]

Alex can i just say that we in England are part of Europe even though i dont want to be    and we use mainly 1/4" or 1/2" like i already said we dont use much 8mm stuff. Do a search of any Uk tool website you will see.