Thread: Are there any router bits that work in timber around 2,800 rpm?

Maybe a 75 or 100 mm fly cutter will work (albeit still slowly) at 2800rpm but anything smaller than 50mm will be SLOOOOOWWWWW.

Router bits ( Carbide and HSS ) do work very well below 10000 rpm. I have a wood mill . Its called the Wadkin LQ Recessor and Borer. It does 3500 and 7000 rpm with a belt position change up top. Pattern makers and stair case builders used them and Wadkin supplied all sorts of small and large diameter HSS cutters for using in them . The guy I bought my one off had the spindle end changed to take ER 32 collets. Pretty sure its 32. it takes from 1/4" up to 1" shank and the metric equivalents . I get a lot of use out of it running small to large router bits and there is no problems running them at 3500rpm and I think even 2000rpm would be the same . Here is some YouTube videos of My one .

Running a small carbide 1/4" fluting bit .

Wadkin LQ Boring and Recessing Machine - YouTube

And a 1/2 "carbide bit. on the slow 3500 rpm speed.

Wadkin LQ Overhead Boring and Recessing Machine. - YouTube

The guy I bought it from put this up before it sold on ebay.

Wadkin mill - YouTube

Rob .

What sort of chuck fits the De Walt RAS. You got any pictures?

could use use normal carbide/HSS but just use a VERY, VERY slow feed rate?


probably talking out my here, but even a cutter moving at 1RPM will still cut, but the loading (feed) on the cutter would need to be that slow and small as to not over load the machine or cause a ton of friction ruining the work. I would assume a router bit doing 1/4 of its usual speed will need more then a 1/4 of its usual feed to ensure its has a similar loading as one at 18,000rpm.

Originally Posted by auscab

Router bits ( Carbide and HSS ) do work very well below 10000 rpm. I have a wood mill . Its called the Wadkin LQ Recessor and Borer. It does 3500 and 7000 rpm with a belt position change up top. Pattern makers and stair case builders used them and Wadkin supplied all sorts of small and large diameter HSS cutters for using in them . The guy I bought my one off had the spindle end changed to take ER 32 collets. Pretty sure its 32. it takes from 1/4" up to 1" shank and the metric equivalents . I get a lot of use out of it running small to large router bits and there is no problems running them at 3500rpm and I think even 2000rpm would be the same .
The guy I bought it from put this up before it sold on ebay.

Hi Rob,

Yeah, standard modern carbide bits should work on my RAS at 2,800 RPM. I got all excited about that watching your linked videos which indicate that routing at various speeds is largely about feed rate as the slow speed produces coarse shavings and chips rather than the fine shavings and dust with a normal router around 20,000 - 25,000 RPM give or take a few thousand RPM, but the cut is much the same. It might also be about high torque at low speeds like I suspect your Wadkin might have, where standard modern handheld routers perhaps rely on high RPM to compensate for relatively low torque.

It also occurred to me after reading your post that I should have just tried my RAS router instead of starting this thread. Because then I would have realised that it ain't gonna work on my RAS because there isn't sufficient height for even a standard 50mm total length router bit to do more than act like a saw at a full depth cut.

My RAS table has a sacrificial 6mm thick MDF top which prevents the motor with router chuck and bit from getting perpendicular, but even with that removed the bottom of the router bit would still be skimming the top of the standard table, so I can forget about routing a 6mm trench on top of 30mm thick workpiece which was my immediate project.

IMG_1515.jpg

Maybe the chuck I got wasn't whatever De Walt recommended, but it certainly won't work on my table or any other table for the same model RAS.

Thanks anyway for your advice and especially the videos of your excellent Wadkin machine.

Damian

Originally Posted by auscab

What sort of chuck fits the De Walt RAS. You got any pictures?

IMG_1514.jpg

5/16 - 24 thread on left hand end that fits into end of spindle opposite saw blade on RAS motor.

Flats on shank to right of thread / to left of knurled ring to allow tightening with spanner, which can be done with supplied large Allen wrench held in saw end of spindle.

Keyless chuck, which was probably pretty flash in the late 1970s when I bought it.

Three jaw drill type chuck, not collet, but machined to better standard than average drill chucks.

Interesting that it's marked 1 -10 and 1/24 - 3/8 (obviously for bit size) which are more or less metric / imperial equivalents and not something the Yanks tended to do with their usually imperial standards, so perhaps it was an aftermarket item that wasn't a De Walt original accessory and why it doesn't fit properly for a router bit.

No special treatment given to the chuck by me. Just been kept in plastic drawers with other RAS bits and pieces for past 40+ years in sheds with almost no signs of even surface corrosion, so probably well made originally.

Really a very good chuck, apart from not being able to do the job for which it was bought and supplied.

Originally Posted by havabeer69

could use use normal carbide/HSS but just use a VERY, VERY slow feed rate?


probably talking out my here, but even a cutter moving at 1RPM will still cut, but the loading (feed) on the cutter would need to be that slow and small as to not over load the machine or cause a ton of friction ruining the work. I would assume a router bit doing 1/4 of its usual speed will need more then a 1/4 of its usual feed to ensure its has a similar loading as one at 18,000rpm.

From watching auscab's videos, I think that's correct, apart possibly from needing higher torque at very low speeds.

Makes sense, when you consider that I have a modern standard blade thicknesser which has a busted auto feed but is handy for manual feeding recycled hardwood into and I can vary the feed rate by the resistance I feel to get a more consistent finish than I might get on another thicknesser I have which is pretty much the same machine but with a segmented head and working auto feed.

Hi, is the pic of the near vertical saw head with back shaft mounted chuck and bit taken with the saw fully raised in the frame, my 7740 would appear to have a lot more clearance than what is showing in the pics.

Also, re the chuck being marked for metric and imperial sizes, the DeWalt saws post DeWalt being taken over by Black and Decker were rebadged Italian saws, often branded both Black and Decker and DeWalt on the same unit, with a statement in the instruction manual that DeWalt is a division of Black and Decker. So European origins but significant customer base in the US could account for a genuine original chuck being marked for both systems. My manuals suggest the back shaft could be used for routing, but also for horizontal or vertical drilling for screw holes, dowelling etc.

Originally Posted by malb

Hi, is the pic of the near vertical saw head with back shaft mounted chuck and bit taken with the saw fully raised in the frame, my 7740 would appear to have a lot more clearance than what is showing in the pics.

Cranked to the top limit. Unless something's seized to stop the column rising, which I doubt as this is the first time it's been raised that high in many years and the newly exposed part of the column is shiny clean.

Originally Posted by malb

Also, re the chuck being marked for metric and imperial sizes, the DeWalt saws post DeWalt being taken over by Black and Decker were rebadged Italian saws, often branded both Black and Decker and DeWalt on the same unit, with a statement in the instruction manual that DeWalt is a division of Black and Decker. So European origins but significant customer base in the US could account for a genuine original chuck being marked for both systems.

Thanks. I didn't know that.

Originally Posted by malb

My manuals suggest the back shaft could be used for routing, but also for horizontal or vertical drilling for screw holes, dowelling etc.

Yes, used horizonatally it would work as a dowelling table with a suitable support made for the workpiece.

Can't see it being used as a vertical drill if it can't be raised any more than I've managed.

Just a guess but 3or 4 flutes might help if can be found - Otherwise It cuts as it does?

Acccording to the manual that came with the RAS and which I dug out tonight

IMG_1533.jpg

de Walt recommended against attempting to use router bits as the speed was too slow. The manual refers to 3,400 RPM which is more than the 2,800 RPM on my saw.

IMG_1531.jpg

It had some sort of adapter to fit an independent router, but clearly that's not the simple chuck I got with the RAS.

IMG_1532.jpg

Also looks like there's no way the RAS was expected to have sufficient clearance above the table to run a router in the chuck I got as the moulder head that was available for it was a fairly shallow affair to sit under the motor. Looks like that could have been fun, or challenging, to use.

IMG_1530.jpg

I had two earlier versions of the DeWalt Radial Arm Docking Saw (RADS) circa 1970 & kept the later green painted version as it had done less and gentler work in a cabinet maker's shop vs Dad's as a builder's saw then in a truss factory. They were very versatile machines capable of doing "everything" from making complex cuts for roof framing, cutting floor & wall framing right down to precise cuts for finish joinery.

We used the 2" Trenching Head to house top & bottom plates for new home builds - no problems taking 2" wide x 1/2" deep full depth in one pass. It also had an adaptor to take a grinding wheel on the blade side shaft, but I've never seen the chuck for the off side. Will have a look to see if mine has that provision on the shaft. I guess it was intended more for boring mortices.

As far as use as a router and cutting speed or more correctly cutting shaft rpm the cutting performance and quality of the cutter / machine combination is dictated by several factors

1. cutter diameter
2. cutter design & geometry
3. machine power
4. machine rpm
5. material (or machine) feed rate
6. depth of cut
7. machine or setup ridigity
8. work piece material properties
9. waste management system - DC etc.

For saw blades, thicknessers etc there is generally a recommended surface feet per minute feed rate for a particular blade design, machine power, and work material.

For your saw the rpm is fixed so the other parameters must be selected / optimized to suit the application at that rpm.

In commercial applications, efficient router / CNC cutter performance, recommended spindle rpm and feed rate can be calculated / determined using manufacturers data on chip load and recommended working ranges to calculate optimum setups.

Chip Load - the size or thickness of the chip that is removed with each flute per revolution.

It is always a matter of selecting an optimum combination of settings - to fast a feed or heavy depth of cut taxes the machine power, hence drops cutter speed, further reducing performance .... spiraling downhill very fast. Slower feed rates, lighter and multiple cuts may not be time efficient but may produce a quality output even on under spec'd setups.

Look up data similar to this @ Technical - Speeds & Feeds for both the cutter and machine.

For DIYer's it's more a matter of perusing the available technical data sheets (if any) available to select the "best match" for the intended use.

The other matter to consider with any machinery setup is the hazards of unguarded cutters and the what if's - what happens IF the cutter fails????

Originally Posted by Mobyturns

Look up data similar to this @ Technical - Speeds & Feeds for both the cutter and machine.

Thanks for that link. Very handy.

On the wider issue of radial arm saws, I've had one in steady use for more than 40 years and never had a problem with it on cross, angle and rip cuts, and doing all sorts of other useful things on it as a saw like cutting tenons, bevels and slots, all in soft and hardwoods. I also often do something which should result in an uncontrollable climb cut that so obsesses the anti-RAS brigade on simple standard cuts, but it doesn't. So I'm a bit mystified by the hostility to radial arm saws in some quarters and a view that they're terribly dangerous and should not be used, like this https://craftgecko.com/why-are-radia...ous-heres-why/

The expert author of the linked article offers these warnings on using a radial arm saw, which of course do not apply to using any other mounted or hand held saw. I particularly like the second one, which would be handy for carpenters on site required to use pretty much every stick out of a pack.

Things Not To Do When Working With A Radial Arm Saw

If you are working with a radial arm saw, there are certain things you want to avoid doing like:

• Avoid cutting stock with foreign objects like stones, nails, or metal.
• Avoid cutting stock that has defects, knots, or splits.
• Avoid using a radial arm saw for ripping unless the riving knife (the spreader) and the anti-kickback devices are provided and properly installed.
• Avoid taking your hand off the operating handle unless the cutting blade (head) is behind the fence.
• Avoid using damaged or dull blades.
• Avoid wearing jewelry, loose clothing, neckties, or work gloves that can become entangled in the moving parts of the saw.
• Avoid leaving a running radial arm saw unattended.
• Avoid cutting “free-hand”; you need to use the fence or back guide to keep the workpiece still while cutting.
• Avoid taking any piece off of the table before the saw is back in its resting position at the back of the saw table.

The one thing we always did was to setup the RADS saw bench and any associated infeed / outfeed tables on a solid base, preferably a concrete slab, and with a fall from front to back of the table so that the saw would not creep forward and would tend to roll back behind the fence if released.

The most significant hazard with older RADS is the lack of a practical saw blade guard that guards the lower half of the blade. The supplied guard could be tilted for ripping but was essentially a fixed height for cross cut operations. I have seen one in a cabinet shop that had a custom fabricated saw guard with side skirts that would ride up over the work piece as the saw was pulled forwards. I think it was an attempt to comply with machinery guarding under early WH&S rules.

A riving knife on a RADS???? None on ours. The saw guard and anti kick back pawls were always adjusted correctly for ripping. In the late 1970's a family friend lost all fingers and a thumb on one hand to a DeWalt RADS whilst ripping boards. We kept wedges on hand and always always always had two operators when ripping longer boards. We often made custom saw horses to support long bearers, beams, joists, rafters etc if they required a angled end cut, or were to be housed etc. Good solid support eliminates or certainly minimizes many hazards.

As far as uncontrolled climb cuts - try using the 2" trenching head!!!!! The operator must apply significant force to counter / prevent the climb cut. I've actually seen a DeWalt RADS (not ours) with a rather deformed chassis as a result of an oops! The pillar and chassis were no longer perpendicular to each other by a rather significant amount!

Over time machinery has become "safer" through well engineered design and development with some encouragement from legislators. However, I'm not so sure that operators are any safer, quite the opposite imho, too much reliance upon "safety features" protecting poorly or untrained operators.