Radial Arm Saw; to Have or not to Have!

Tool of the Week Winner
This project won Tool of the Week at HomemadeTools.net

 

Best Documented Build WinnerThis Project also won ‘Best Documented Build’ for March 2016 at Homemade Tools.net

 
 To have or not to have a Radial Arm Saw? That is the question.The following is the text of an item, an abridged version of which, I posted on the Homemadetools.net forum recently. It concerns the perennial argument regarding Radial Arm Saws. Of its nature, the post was brief and therefore, certain safety issues had to be omitted. Be aware however, that every possible safety procedure is adhered to in my shop when using the RAS or any other machine or  tool (always including eye-protection and ear-protection)..
The article is my modest contribution to the argument ‘for’ Radial Arm Saws. I would appreciate feedback from other RAS users.
Please note: you are responsible for your own safety. Your shop, your tools and machines, machine settings, maintenance and methods etc. may all vary from mine. The methods and systems described here work for me. They may not work for you. It is up to you to ensure safe systems in your own work shop. Be aware that all machinery and even hand tools are dangerous; you may suffer serious and even fatal injury if proper care is not taken. You have been warned.

The debate on Radial Arm Saws seems to go on forever. I’m in the “For” category. To help those who may be ‘on the fence’ make up their minds and to perhaps, persuade those in the “Against” category to look again, here is a look at my RAS set-up. It was developed primarily with safety in mind but also convenience and accuracy.

There is little doubt that the RAS is a versatile cutting machine. It can be used for cross-cutting, ripping, cutting mitres and bevels and much more. But like most good things in life, there are trade-offs. In the case of the RAS, the trade-off is simple, if we do not adjust and tune it up properly, the quality and accuracy of the cuts will not be optimum. Slightly off square cuts and burned edges may be the result. Or worse, kick-back when ripping may ensue.

Luckily, all it takes to produce crisp accurate cuts and safe cuts, is a bit of tuning and adjusting every now and then, and safe working procedures. But tuning-up the RAS is for another post. Here, I simply wish to showcase my Radial Arm Saw set-up and to show some of the operations that I perform on the saw.

So, here we go.
Firstly, there is the table itself, which in my case, is not sacrificial:
Radial Arm Saw Table/jig-img_5208%5B1%5D.jpg

It is made from melamine-faced particleboard; for ease of cleaning and for slipperiness or slickness, if you like.
Next comes a sideways sliding table (x direction, that is) made from the same material. This might seem a strange idea with and RAS but, read on. This auxiliary table is constructed in a way that it hooks over or straddles the rear fence of the original table in a manner that prevents slop.
Radial Arm Saw Table/jig-img_5209%5B1%5D.jpgRadial Arm Saw Table/jig-img_5211%5B1%5D.jpg
Kerf lines are visible on the auxiliary table in the photo from previous ripping operations; the auxiliary table is sacrificial.
The back fence of this auxiliary table is designed to be exactly parallel with the original table’s fence. Examination of the photographs will show that the are three clamping devices which hold down the work piece firmly when cross cutting or ripping. Another important feature of the auxiliary table is a pin which automatically drops into a corresponding hole in the original table’s fence when aligned, thus, locking the auxiliary table into place when cross-cutting, for example.
Radial Arm Saw Table/jig-img_5210%5B1%5D.jpg
The following photo shows a board of walnut ready to be cross-cut to length. It is clamped in position, tight against the fence. A stop arrangement to the right ensures that repeat cuts will be exactly the same. The auxiliary table’s lock pin is in the down position, so everything is solid. The cut can be made safely and cleanly with no hands or thumbs needing to be near the blade. In fact, the cut cut could be made with just one hand operating the saw. A word of warning: after a cross cut always let the saw-head slide back to its home position and kill the power and let the blade come to a stop before un-clamping and re-clamping the wood for the next cut. If the cut-off piece is lying in the path of the blade, kill the power and let the blade come to a stop before attempting to remove the piece of wood. Never reach around the spinning blade to lift a piece of wood. These are basic safety precautions with an RAS.
Radial Arm Saw Table/jig-img_5213%5B1%5D.jpg
The next photo shows the set-up for a rip cut. Here it is set up for trimming the edge of a board. It could just as easy be for straightening the edge of a board, ripping down the middle or be even set up to cut tapers. My particular set-up has a board-length capacity of about 4ft. This works OK for me as most of my projects do not require boards longer than that. If I want to rip cut a longer board I make special arrangements for that.  Ed Waggoner Sr. demonstrates a method that could be used on his YouTube video. For the most part, my set-up works for me; everything is clamped down and my hands and fingers are kept well out of the way of the blade. If you commonly need to rip longer stock, then make a longer sliding table. But make sure there is absolutely no slop whatsoever in the sliding table; it must be dead solid so that the board travels dead straight into the saw blade. I find that a properly built sliding table such as this with adequate clamping, keeps the board much straighter relative to the blade than boards held by hand against a fence. What you don’t want is wobble or wander in the board as it travels into the blade. That is the sort of thing that causes kick-back and also a spoiled cut. Finally, if you are attempting to rip a board,make sure the anti-kick pawls and the splitter are in place.
Radial Arm Saw Table/jig-img_5228%5B2%5D.jpg
Here’s a view looking towards the blade. The blade-guard can be seen to the right of the blade in the picture. Just a smidgen (i.e. a small unit of measure in wood-working parlance!) is about to be taken off the edge of the board.
Radial Arm Saw Table/jig-img_5229%5B1%5D.jpg
And finally, after the cut; the sliding table has been moved from left to right (from the operator’s point of view standing in front of the table) and the operator didn’t need to stand in the line of fire of the blade. All is done from the front of the table. Once the cut is complete, shut off the power and allow the blade to come to a stop before you attempt to remove the board from the clamps. The table can then be slid back to the start position and a new board clamped in for the next cut.
Radial Arm Saw Table/jig-img_5230%5B2%5D.jpg
Now you can see why I wanted to use a melamine faced board for the tables as it slides relatively easily, one sheet against another.
My set-up is also great for cutting medium to small sized sheet materials. The next photo shows a plywood square panel being cut to size. Cutting a panel like this is basically like doing long cross-cuts. The panel is clamped down and temporary block clamped behind the panel determines the length of the side of the board.
Radial Arm Saw Table/jig-img_5215%5B1%5D.jpg
And now a nice little jig that simply clamps straight onto the auxiliary table against the fence. Can you see what it is? It may come as a surprise to know that it is actually a circle-cutting jig; and one that works remarkably well. How, you might ask, does one cut a circle (safely) on a RAS?
Radial Arm Saw Table/jig-img_5216%5B1%5D.jpg
Well, the principle is very simple: keep cutting the corners off a square shape, again and again. and you will end up with a circle. In other words, a series of cross-cuts (what the RAS excels at). Believe it or not, from set-up to finished circle only takes a few minutes.
The following sequence of photos show the setting up and cutting process:
First setting the jig for a 14″ dia. circle.
Radial Arm Saw Table/jig-img_5217%5B2%5D.jpg
Now, see the knob on the left that tightens down the setting on the jig:
Radial Arm Saw Table/jig-img_5218%5B2%5D.jpg
Now, imagine the square of plywood we cut earlier; we find its centre-point and drill an appropriately sized hole and drop it over the pin on the jig. Now, we simply hold it (firmly) in place and cut off the first corner; just as if we were doing a regular cross-cut.
Radial Arm Saw Table/jig-img_5219%5B1%5D.jpg
The photo above shows the first corner cut off. It is now only a matter of rotating the plywood 90 degrees and cutting off the next corner and so on. When all four corners are cut off, we start on the next lot of smaller corners until we end up with what we see in the next photos:
Radial Arm Saw Table/jig-img_5221%5B1%5D.jpgRadial Arm Saw Table/jig-img_5222%5B1%5D.jpg,
A near-perfect circle and a little pile of (triangular) debris.
All that is left now is to lock the blade-head at the appropriate position along the arm and turn the disc-shaped plywood into the blade to trim off the hairs:
Radial Arm Saw Table/jig-img_5223%5B1%5D.jpg.                                                                                                             Don’t be in a hurry; make sure all possible corners have been cut off the disc before performing the last operation.
Of course, a Radial Arm Saw is capable of doing all sorts of unusual jobs but I will cover just one more of the common tasks that I use the RAS for; cutting mitres (perhaps ‘miters’ where you are). Again, this requires only the simplest of jigs clamped down onto the auxiliary table; a fence fixed at the required angle to an accurately squared piece of MDF :
Radial Arm Saw Table/jig-img_5226%5B1%5D.jpg
The final photos show a mitre (miter) after being nipped off the end of a 2″ strip of plywood and the cut being checked against a 45 degree square. Looks pretty accurate to me!
Radial Arm Saw Table/jig-img_5225%5B1%5D.jpgRadial Arm Saw Table/jig-img_5227%5B1%5D.jpg
To conclude; I designed this set-up primarily with safety in mind. Secondly with accuracy and thirdly with convenience in mind. I hope it will persuade some of the Naysayers that the RAS is not so bad after all. Indeed, it is pretty well the mainstay of my shop. Few projects take place without some recourse to my RAS. Moreover, it is no more dangerous (and no less forgiving) than any other machine. As with any machine, it must be treated with respect. All machines are dangerous. Even hand tools can be deadly if incorrectly used. So, whatever else we do, let’s think safe and keep safe.

 

4 Comments

  1. This is great, thank you for sharing it. I stumbled across your site because I am attempting to tune up my dad’s old 7770 RAS and I discovered there’s a bow in the fence – out towards the user.
    Now, I carefully ripped a new piece of MDF to use as the fence and the bow exists with the new fence. The curve must originate with the table then, and the fence must be conforming to the curve in the table.
    My next step would be to replace the table, and seeing the safety measures you’ve built into yours, I’d love to replicate it. However I do not have a tool-filled shop(yet). How would you suggest I create a table with a great straight back to keep a straight fence locked in?

    • Brendon

      February 14, 2017 at 12:51 am

      Hi
      Thanks for your interest in my blog.
      It should be possible to make a new mdf table with integral fence by carefully keeping everything square. The table must be flat and rigid; a double thickness of 3/4″ MDF is recommended. Also, you will have to ensure that the table is level relative to the arm of the saw (not necessarily to the bubble in a level). In other words, the travel of the saw must be even with the table in all positions. Ensure that the table is securely bolted down to the frame. Check it again for level relative to the arm and adjust if necessary. There are lots of guides as to how to do this and on building a new table, on the net. The fence must be set perfectly square to the saw when the saw is set at 90 degrees.
      Once you do get everything set up square and level, I would not recommend moving the arm to cut miters; use a simple jig instead. Make sure everything is clamped securely down.
      Setting the RAS can take some time (this is one of the reasons some folk don’t like the RAS) so it is much quicker to use a miter-cutting jig. Moreover, Radial arm saws do have a tendency to lose their set.
      It would be well worth your while getting onto Amazon. There are a number of books there on the subject of the RAS. They are full of tips and ideas and any of them should cover the set-up of the saw and table. Importantly, these books will also teach you about safety with the RAS. Remember, the RAS is a dangerous machine; you are responsible for your own safety. I cannot emphasize this enough.

      I have found my clamp-down system to be the most important aspect of my set-up. We mostly do cross-cutting with the RAS and clamping the work down means the hands can be kept well away from the blade. I also pull the saw gently through the work; the spinning blade suddenly meeting the wood with a whack could cause problems.
      Be extra, extra careful if you decide to rip with the RAS. This is when the infamous kick-back is most likely to occur. Moreover, do not use radial arm saws for ripping unless the spreader (riving knife) and anti-kickback devices are provided and properly adjusted. You would be better advised to rip on the Band saw. In any case using the RAS for ripping require a lot of room; the overall length of the saw table (both infeed and outfeed) should be twice the length of the longest pieces of lumber.

      All that being said, I feel happier using the RAS for cross-cutting than using any form of chop-saw. I always feel much too close to the spinning blade with the chop-saw.

      I realize that this answer to your question is all too brief. My advice is to get on the net and to read one of the books. There is a shed-load of information out there.

      Safety notes:

      What you should avoid when working with a radial arm saw:
      Do not use radial arm saws for ripping unless the spreader (riving knife) and anti-kickback devices are provided and properly adjusted. Ideally, rip on the band saw.
      Do not take your hand away from the operating handle unless the cutting head is behind the fence.
      Do not remove the stock from a saw table until the blade has been returned to its “resting” position at the back of the saw table. Use a stick or brush to remove scrap from the saw table.
      Keep the table surface clean and clear of tools, offcuts or other objects.
      Do not cut “free hand”. Use the back guide or fence, or other device to keep the workpiece from moving.
      Do not use cracked or dull blades.
      Do not leave a running saw unattended – leave only after the saw has been turned off and it has come to a complete stop.
      Do not wear loose clothing.
      Always:
      Wear safety glasses or goggles, or a face shield (with safety glasses or goggles).
      Wear hearing protection that is suitable for the level and frequency of the noise you are exposed to in the woodworking area.
      Wear protective footwear when required. Ensure the floor is clean and not slippy with sawdust.
      Feed stock against the direction of the blade (the blade should move downward when viewed by the operator).
      Only use saw blades rated at or above the speed of the saw arbour. (An arbour is the attachment from motor to blade). Only use the correct blade for your particular saw (see owner’s manual).
      Use only the accessories designed for that specific saw and application.
      Ensure the guard consists of two parts:
      Upper hood type that covers arbour
      Lower guard that rides on the stock, adjusting automatically to the thickness being cut.
      Stand on the handle side when cross cutting. Pull the cutting head with the hand nearest the handle and maneuver the stock with the other hand or clamp it down.
      Make sure the hand holding the stock is never in line with the blade.
      Return the cutting head completely to the back of the saw table after each cut. The saw should be designed and set up so that the blade will not move forward under its own weight or if the machine is vibrating.
      When ripping, make sure that the overall length of the saw table (both infeed and outfeed) is twice the length of the longest pieces of lumber.
      When ripping, make sure that the stock is fed against the direction of the blade (from the side where the saw blade rotates upward toward the operator). The blade should extend slightly into the table. The motor head must be locked at the correct height and angle.
      Clamp stock to the table on one side of the saw blade, when making mitre, bevel or compound mitre cuts. Clamping prevents the wood from sliding along the fence during the cut.
      Turn off the saw when making any adjustments or changes in the set up.
      Make measurements by placing the wood to be cut against the stop gauge. When measuring with a tape measure or ruler is necessary, turn off the saw until the measuring is complete.

      Whatever you do with a RAS, think and consider your personal safety and the safety of anyone else in the shop. Keep children away from the RAS or any other machines in the shop.

      It may seem like a pain in the butt, but learn all you can about safety with the RAS (and all machine tools).

      Brendon

  2. Wow. Absolutely beautiful set up. I too am a big fan of the RAS. Some day I will find myself a nice dewalt. For now I am enjoying my restored 1970s Craftsman. I would love to see more details about your cross cut and ripping sleds. Do you have them documented somewhere?

    • Brendon

      September 8, 2017 at 7:32 am

      Hi Todd,
      Thanks for your comment.
      There is a post of mine on Homemadetools.net with regard to my RAS.
      Cheers,
      Brendon

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