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Here I plan to place some useful hints and tips gleaned from feedback and forums. If you have anything that you feel could be included then please email them to me.

Imperial to Metric Drill conversion  

From Pierre Veuger in Holland

 For many years I have visited Britain and spoken to British technical professionals or DIY-people.
They have always told me how perfect the imperial system is. When I ask them what the weight of a pint of water is, or the volume of one kilogram of petrol
I have never received the correct answer or even an answer. The metric system is very helpful for these problems.

Why am I writing this?

In Holland we were brought up, especially in secondary school in the late 50’s, with both systems. We had to calculate what the price of a cubic meter of wood was in Holland after being imported from Britain or Sweden. The original price was in pounds, shillings and pence, by yards or cubic feet etc. You had to pay the bank for exchange, translate everything from English to Dutch and so on. Then I went to university after A levels, and a professor came with a brilliant solution.

He  told us that one sixteenth of an inch was approx one point six millimetres, or in Dutch English one sixteenth was one six tens. It is a rather accurate calculation. Because 16 sixteenths, or one inch, is 25,6 millimetres. The accurate answer is 25,4 millimetres, fault: 0,2 millimetre, or 0,8 percent. I think that is accurate enough for woodworking, because the glue needs some room too.

If you have to drill a hole of 5/16”, and in Holland we do not have imperial drills, you say to yourself: 5/16 equals 5*1,6, which is 8 millimetres.  ¼ inch equals 4/16 inch, the metric size will be 4*1,6 =6,4 millimetres. I then use a drill of 6,5 millimetres in wood.

This method is not accurate enough for precise metal machining or drilling of course.

For wood it always works.

A little list:

Inch                                                                  mm                   drill size

1/8                   2/16                 2*1,6               3.2                   3.2

1/4                   4/16                 4*1,6               6.4                   6.5

5/16                 5/16                 5*1,6               8                      8

3/8                   6/16                 6*1.6               9.6                   9.5

½                     8/16                 8*1.6               12.6                 12.5

 With this method you do not need a calculator, but a simple clear brain.

I have met some very keen woodworkers; sometimes you see their pictures in magazines…

They all agreed, one of them always calls me one sixteens…

Pierre Veuger, Driel, The Netherlands

For any scale checking, fix the plate with the bolts passing through the plain holes and not the slotted ones. You probably will not be able to pass any fixing bolts through the alloy rails in this position as the holes will not line up. Either drill more holes or return to the slotted holes after checking.


First up from Dave R. on the 'Rat forum in response to problems with through dovetails. The info he gives is worth checking on your own machine.

"First, it isn't unusual to have to stray a little from the spiral and button settings. It depends upon a few things. On my Rat the correct spiral settings are actually different numbers left and right. They aren't really degree marks either.

You should go back to the button setting first. Check the scale position on the Router Plate. Do this by first removing the router from the Router Plate and putting the plate back on the Rat. Then clamp a good flat, narrow piece of wood in the cutter position so that it extends up through the slots in the plates.

Measure the distance between the back side of the piece of wood to some point on the scale. I did this on the 60 mark if I remember. It should be 60mm but mine was short by 2.5mm.

If the distance is short, make a note to add the variance to the button setting. If it is over, subtract the variance.

Keep in mind that it is the button position that affects the width of the pins. If the setting is too short, you could end up with narrow pins.

After checking this, chase down the spiral settings. The drawer bits are so tiny that it can be difficult to see if you've got the angle right. Since they come in pairs, you could use one to check the angle you're cutting with the other.

I have used the angle gauges that are available from the US WoodRat dealer at For these to work properly, the baseplate needs to be accurately squared to the face of the Rat

As to the alignment problem, first look at the cable to make sure it is taut. If the carriage moves between cutting the test cut in the slat and making the mark, you could indeed have an alignment problem. Assuming the cable is taut make sure you don't move the carriage.

For marking the cuts, I like to carry the marks up over the top of the machine and I put a centre mark so you have something that looks like this | | | on the top of the machine. This seems to help me with alignment.

Another thing I do is use a .5mm mechanical pencil for making the mark. I extend the lead out so that I can get the lead in tight along the cut on the slat.

Hope some of that stuff helps. Good luck."


Further explained by Dave

"Roger, the left scale on the Router Plate indicates the distance from the front face of the Rat when the Router Plate is pushed back against the rear orange stop. Put the plate in place as if the router is installed and you are going to set the button. Clamp a straight piece of wood in the cutter position so it will stick up though the slots in the two plates. Now you can easily measure the distance from the face of the machine (it should be the same as the back surface of the piece of wood) to a point on the left hand scale.

On my Rat, the 60 position (I think it is just marked 6) is 57.5mm from the face of the Rat. This means that if I need a setting of 60 for a given bit and set the button to 60, I'm really setting it 57.5mm from the face. To get a real setting of 60 then I must set the button at 62.5.

I borrowed Henry's drawing from the manual and added to it. I hope it helps to clarify things."

Here you go. This went quicker than I thought. Should be self-explanatory.


Resist using silicone based lubricants on your WoodRat. Much better to use some dry PTFE ( Teflon) lubricant. If silicones come into contact with your woodwork you will have many problems with your finish, especially cellulose based materials. It causes circular patches and other unexpected results.


Sometimes when tracking your work past the dust chute, the carriage can 'stick'. I have found that occasionally the work 'springs' a very small amount and just catches on the sharp vertical edges of the opening in the channel. The cure for me is to very lightly file a very shallow bevel on each vertical edge. This bevel allows the work to ride back out flush with the face and thus no jamming.

                            bevel---- __/  dust chute \____channel__

                                                | work|-------travel 


 "I have had a couple of instances of the cam lock handles falling off.  The little screw that holds them in place progressively works loose with use of the handles.  Its worth checking the screws and tightening them as required on a routine basis." 

Hip Dog 'Rat forum
Thread locking liquid can be useful on the threads.


"I've found that what helps me (and may be useful to others with poor eyesight) is to make pencil marks for my cuts in the usual way using a 0.7mm. fine clutch pencil and then crank the cutter E/W until it JUST removes the line. Similarly for depth, I do the same with the fine height adjuster on the router whilst it's running."  Tony Spear 'Rat Forum


"I've made several sizes of dowel pops for the woodrat and had great success with them. I use them to make knitting needles which must be sized very precisely and also be extremely smooth, so it takes a bit of trial and error to get the cut right even after I have made the dowel pop with the correct diameter hole. I shoot for just slightly oversized dowels for my application and then sand to the correct diameter.

The first key to success is to use the largest straight cutter you have. Even on small holes (the smallest I make is 2mm). This gives you the fastest bit rotation at the bit edge, which translates into more cuts per inch. The next key is the dowel pop itself. The jig will work better if you make it from thicker stock. This gives the dowel more support as it spins through hole and leaves less dowel past the whole to wobble. This is especially important when making tiny dowels. Also thicker stock will give you better feedback regarding the feed angle. It is very easy to feed from a downward angle to try to clear the bottom of the rats base plate, but thicker stock in your jig will help you keep your feed angle perpendicular to the jig. 1 1/2" works well for me on the small stuff (two pieces of plywood sandwiched together do the trick).

Make sure you have the cutter edge slightly in front of the hole in your board and that it is truly cutting at the very top of the hole (this is where you might have to try a few test pieces). Once you have the bit depth set correctly the diameter of the hole is irrelevant since whatever you feed into the bit will come out exactly the size of the whole (unless you feed it at an extreme angle). Make sure your cutter is sharp and that you are not taking off too much wood at one time (especially important with woods prone to tear out, or very dense woods). Also check that you are spinning the rod in the correct direction (against the rotation of the cutter from the left side of the rat, as if you were driving a screw in, not out). And Lastly once you get the rod just through the hole spin it as fast as your drill will spin but make your feed rate slow, straight and smooth. Keep spinning as you back the rod out and you should get pretty clean results. I leave the rod in the drill after I have cut it, grab a piece of sand paper (150 grit usually) and give the rod a quick sanding as if it were on a lathe. That way the drill does the work of spinning the dowel and you can be sure that you will not sand it out of shape as can sometimes happen when you do it by hand. If you are just using the dowels to make joints or pin mortise and tenons you should be able to get a satisfactory finish right out of the dowel pop.

Once you get the results you are looking for make as many dowels of that size as you can stomach so you will have plenty for other projects and remember that the first inch or two of the dowels you make usually wont be a good as the rest so give yourself some extra stock length until you get the hang of it."

Dan Chaffin  WoodRat Forum

Mounting your Router

If you own a DeWalt or one of the clones then the pre-drilled mounting holes are available to ensure that the router is fixed centrally on the sliding plate. Finding the central fixing for another type of router can easily be achieved by Dave R's method:-

" Take a scrap of wood about 3 inches long and a bit wider than the slot in the plate. Rabbet (rebate) the long edges to get a tight fit in the slot. Drill a 1/4" hole midway between the shoulders of the rabbet. Insert the block into the slot and install a 1/4" piece of rod or a drill bit in the router and stick it in the block. Now your router is centred."

Dave R WoodRat Forum

Fence and Clamp Mods

Lloyd Nakatani has emailed me some interesting changes he has made to his WoodRat. Lloyd says he is a newbie but has already sorted his machine with a few simple adjustments. Maybe self-adhesive PTFE tape on the back of the plastic fence would do the same thing?

"Here are some mods I made to my newly acquired Woodrat.

1. I eliminated the "rattle" by simply sanding down the flat on each fixed plastic clamp that rests on the sliding bar until the gap between clamp and the channel was eliminated in the upper and lower portions of the clamp. This was a no-cost and easy solution.

2. I sanded the clamping face of each fixed plastic clamp until the face was square to the channel.

The original face was noticeably off-square which adversely affected clamping effectiveness.

3. I noticed that under clamping pressure, the post around which the white lever portion rotates would deflect so that the face of the moving and fixed clamps were no longer parallel. I fixed this by sloping the back face of the clamp (the part with the yellow plastic strap) so that the clamp was "sprung" when no clamping pressure was applied.

Pressure "un-springs" the clamp face. This is the same principle as sprung vise faces.

4. I mounted the new vernier caliper on the T-slot along the bottom of the channel. The mounting is cleaner, allows me to keep the original fixed clamp on the machine, and is easy to disengage when not needed.

-- Lloyd Nakatani"

Thanks LLoyd,

Some excellent advice there.

Tenon and/or sliding dovetail

"Hello for Tennessee, USA.  I am very glad I found your site.  Let me offer an idea, that works for me and my be of use to others:

I found, what is for me, an easier way to make a tenon and/or sliding dovetail.  Forget the Block and the methods shown on page 45 of Manual #9, here is how I make them, and I hope it might be of use to others.
After  cut my trench, I keep my depth of cut and after I have found the center of the board, I put the piece that will be my sliding dovetail in the center cam clamp.  I line the center of my bit with the mark that identifies the center of my board, turn on the router and then move the carriage just slightly to the right, thereby making an impression of the bit in the end of the board.  This eliminates all of the instructions given on page 45.
Once I have this "mark" of the bit on the end of the board, I use the precision stop to move the bit to the left and right of that "mark" and make my cut.  Perfect fit every time, the first time.
It is really the same principle as "cutting a test socket" as explained on page 81 only applied to the East/West cut rather than the North South cut for the thru dovetail"

I have drawn up two sketchup 5 3D drawings which hopefully will explain things a little more clearly. Download these two zipped files, unzip them and view them with your sketchup viewer or program.

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Here is another diagram courtesy of Dave Richards that clearly explains the process.



Riser Plates

When using riser plates always ensure that they are fully in line with the face of the channel. It has been my experience that when you find some slight run-out when machining work that is in contact with face it is because the riser plate is projecting out a very small amount. I have noticed on my machine that the MDF plates gradually creep out over time and I have not as yet found an explanation.  I suppose that this happens over a period of a couple of months or so irrespective of how tight the plate fixing bolt holes are. I have been troubled by this a few times and it seems to happen when you are doing some delicate work on the last piece of wood that you have!

Changing Router Bits

Al Shaver has a couple of anti-swearing tips:

"I just read on your site the (Angele's) idea for the RatBag to catch router bits as they tumble to the ground.

I have only had my WoodRat for a couple of months, but right after my first bit hit the ground I did two simple things that I thought must be standard practice.

1. I put a rubber mat under the Rat.   border="0" 

2. I made from a scrap of hardboard a quick approximation of the centre finding thingamajig (call it a ‘bit stop’).  When loosening a bit I first put the bit-stop in the centre finding track.  When the bit is loose and has fallen to the depth of the bit-stop I can easily raise the bit a fraction, flick the bit stop forward towards me, and then pull the bit down, knowing it is loose."   

         border="0" border="0" border="0"

Al Shaver

Simple tips that could save a lot of money!

Anti- droop!

Here is a simple and quick remedy for any rattle or droop when using a mortise rail with heavier work sent in my Roger Sinden. Just use a roller stand underneath the rail!!


Quick dovetails

When Ray Parker has to make a quick batch of basic dovetails on his full sized WoodRat then he doesn't mess around with scales and test cuts. He purchased a plate for a little rat and mounts that on his full sized one. Quick and easy! Well done Ray. (only one angle of tail though)


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