Radial Arm Saw Help
#11
  
I just bought a used Craftsman 10" RAS.  It had a OSB table on it and no fence.  I''m replacing it.  It is a 113.199250 or 113.199200.
Making this table has me stumped.  I just can't see the geometry in in it.
The fence has to be perpendicular to the arm travel.  But the blade is offset from the arm a few inches.  I'm sure that will all work out.

My question is:
Where should the back of the main (front table) be?  I think it should be at the forward most edge of the blade (a vertical line dropped from the front edge of the blade to the table with the blade in the most rear position).  Is this correct?
That will give me only 13" of crosscut capability.  Is that what most folks get?  

I'm ready to drill and counter bore my bolts for the main table.  I just want to make sure my placement of the front table is correct.

Thanks for your help in advance.

RP
Brenham, Texas
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#12
  Re: Radial Arm Saw Help by RPE1 (I just bought a used...)
Rear mounting hole centerline should be about 1.12 from the back edge of the main table. Then you have a fence piece 3/4 to 7/8 thick, then a 2" strip then the rear piece which is wide enough to reach the rear of the frame.
Depending on whether you have the fence in front or behind the spacer (most of the time in front) it effects your cross cut and thickness capabilities.
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#13
  Re: Radial Arm Saw Help by RPE1 (I just bought a used...)
Do you want it where it was originally designed to be? If so, I would do these steps to get it pretty close.
Rotate motor to rip with blade inboard. (No, we're not going change this thread into an argument about ripping on the R.A.S.!)
Making sure the rip indicator is in the center of its adjustment, lock the carriage where it reads zero on the rip scale.
The back side of the blade is where the back of the front table should be.
I would just bolt the front table parallel to the front frame, knowing that I can make adjustments to the saw to dial in near perfection.
The only thing I find that is critical with the front table, is that it is flat and on a plane that is perpendicular to the column.
Unfortunately, a lot of us skip this important first step in adjustment and just measure up from the frame and call it good enough. It's not.

By the way, without saying anything ripping; the back table (behind the removable fence) should be thinner than the front which is typically accomplished by adding a piece of Masonite to the front table. Sandwiching the fence between the two tables allows it to be easily shifted for a zero clearance fence. Preventing tear out is not the main reason; A fresh saw cut through the fence is by far the easiest way to line up a cut.

Good luck and don't forget to use zero hook angle blade.
Sign at N.E. Vocational School Cabinetmaking Shop 1976, "Free knowledge given daily... Bring your own container"
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#14
  Re: RE: Radial Arm Saw Help by MstrCarpenter (Do you want it where...)
(06-02-2019, 12:03 AM)MstrCarpenter Wrote: Do you want it where it was originally designed to be? If so, I would do these steps to get it pretty close.
Rotate motor to rip with blade inboard. (No, we're not going change this thread into an argument about ripping on the R.A.S.!)
Making sure the rip indicator is in the center of its adjustment, lock the carriage where it reads zero on the rip scale.
The back side of the blade is where the back of the front table should be.
I would just bolt the front table parallel to the front frame, knowing that I can make adjustments to the saw to dial in near perfection.
The only thing I find that is critical with the front table, is that it is flat and on a plane that is perpendicular to the column.
Unfortunately, a lot of us skip this important first step in adjustment and just measure up from the frame and call it good enough. It's not.

By the way, without saying anything ripping; the back table (behind the removable fence) should be thinner than the front which is typically accomplished by adding a piece of Masonite to the front table. Sandwiching the fence between the two tables allows it to be easily shifted for a zero clearance fence. Preventing tear out is not the main reason; A fresh saw cut through the fence is by far the easiest way to line up a cut.

Good luck and don't forget to use zero hook angle blade.

MstrCarpenter, Thanks for your response.  


RP
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#15
  Re: RE: Radial Arm Saw Help by MstrCarpenter (Do you want it where...)
(06-02-2019, 12:03 AM)MstrCarpenter Wrote: Do you want it where it was originally designed to be? If so, I would do these steps to get it pretty close.
Rotate motor to rip with blade inboard. (No, we're not going change this thread into an argument about ripping on the R.A.S.!)
Making sure the rip indicator is in the center of its adjustment, lock the carriage where it reads zero on the rip scale.
The back side of the blade is where the back of the front table should be.
I would just bolt the front table parallel to the front frame, knowing that I can make adjustments to the saw to dial in near perfection.
The only thing I find that is critical with the front table, is that it is flat and on a plane that is perpendicular to the column.
Unfortunately, a lot of us skip this important first step in adjustment and just measure up from the frame and call it good enough. It's not.

By the way, without saying anything ripping; the back table (behind the removable fence) should be thinner than the front which is typically accomplished by adding a piece of Masonite to the front table. Sandwiching the fence between the two tables allows it to be easily shifted for a zero clearance fence. Preventing tear out is not the main reason; A fresh saw cut through the fence is by far the easiest way to line up a cut.

Good luck and don't forget to use zero hook angle blade.

This is the correct way to determine where to place the front table wrt the rip scale. But if you don’t take care with the rest of the placement you may have trouble down the road.

A lot of the craftsmen have a spring loaded ball bearing indent for 90° and 45°.  If the fence is not perpendicular to the arm you will constantly be fighting that spring  to keep the saw aligned, hence the bad rep for radial arm saws and alignment.

Once you have the front table placed, you don’t want it exactly perpendicular to the column, rather you want it parallel to the travel of the saw as it it goes down the arm.  There will be flex as the heavy motor moves farther away from the column.  One of the most liked features of the RAS is its ability to cut dadoes quickly.  If you don’t account for the flex, your dadoes will not be uniform depth.

Jon Eakes book is the Bible on ras adjustment.  It would be good to try to find it, either on line or in print.
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#16
  Re: RE: Radial Arm Saw Help by srv52761 ([quote='MstrCarpente...)
(06-02-2019, 08:46 AM)srv52761 Wrote: This is the correct way to determine where to place the front table wrt the rip scale. But if you don’t take care with the rest of the placement you may have trouble down the road.

A lot of the craftsmen have a spring loaded ball bearing indent for 90° and 45°.  If the fence is not perpendicular to the arm you will constantly be fighting that spring  to keep the saw aligned, hence the bad rep for radial arm saws and alignment.

Once you have the front table placed, you don’t want it exactly perpendicular to the column, rather you want it parallel to the travel of the saw as it it goes down the arm.  There will be flex as the heavy motor moves farther away from the column.  One of the most liked features of the RAS is its ability to cut dadoes quickly.  If you don’t account for the flex, your dadoes will not be uniform depth.

Jon Eakes book is the Bible on ras adjustment.  It would be good to try to find it, either on line or in print.
I haven't read that Bible, but I'm sure by the number of times it's referred to that I can learn a few more things.
I was trying to explain quickly that a lot of people skip this important step. Your direction and explanation of why it's important is much better than mine (which was only correct in theory).
I have not experienced difficulty with indents. Both of my DeWalts (and the old school B&D) have wedge shaped levers that securely and precisely locate 45* and 90*, so I have not experienced difficulty with indents.  However, I am curious how to accurately mount the front table to align with them.  Is there any play in the mounting bolts for the column on the zip code saws? My Craftsman is set to cut perfect 90*s, and that's pretty much where it's stayed for over 10 years now.
Sign at N.E. Vocational School Cabinetmaking Shop 1976, "Free knowledge given daily... Bring your own container"
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#17
  Re: RE: Radial Arm Saw Help by MstrCarpenter ([quote='srv52761' pi...)
(06-02-2019, 12:43 PM)MstrCarpenter Wrote: I haven't read that Bible, but I'm sure by the number of times it's referred to that I can learn a few more things.
I was trying to explain quickly that a lot of people skip this important step. Your direction and explanation of why it's important is much better than mine (which was only correct in theory).
I have not experienced difficulty with indents. Both of my DeWalts (and the old school B&D) have wedge shaped levers that securely and precisely locate 45* and 90*, so I have not experienced difficulty with indents.  However, I am curious how to accurately mount the front table to align with them.  Is there any play in the mounting bolts for the column on the zip code saws? My Craftsman is set to cut perfect 90*s, and that's pretty much where it's stayed for over 10 years now.

 Yes the front table has enlarged holes so you can set the table 90 degrees from the travel.
Front table 13.5" X 40",   there are 6 mounting holes with the back ones centered 1 " from back,  tabled is centered left to right.
Back fences  one is 2" wide the other on is 5.25" wide with a 3' wide and 2" deep notch cut out of front edges centered on the column , notch 16.5" from left and 19.5" from right, this is for arbor when turned vertically.
The fence is .75" thick , height is about 1.5 high.
You change the location of the back pieces and fence for different operations.   Roly
Note this is for a old Craftsman RAS and the table was 1" solid oak so please verify these measurements for your saw. Forgot about a recess on underside of table for hand clearance when cranking.
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#18
  Re: RE: Radial Arm Saw Help by MstrCarpenter ([quote='srv52761' pi...)
Quote:MstrCarpenter
........  However, I am curious how to accurately mount the front table to align with them.  Is there any play in the mounting bolts for the column on the zip code saws? My Craftsman is set to cut perfect 90*s, and that's pretty much where it's stayed for over 10 years now.


I have only owned Dewalts, but my first Dewalt, a 7740, suffered from the ball bearing indents, also.
My later Dewalts, a MBF and a 7790 had/have the wedge shaped lever.  I love that design as even if it wears, it stays centered in the female “v”; it just goes deeper.
On the Dewalts and probably the Craftsman and others there are screws on the back of the 90° lever clamp.  By loosening one and tightening the other you can adjust where that lever is when it engages the indents.   (I just checked my Eakes book, the craftsman uses three Allen screws to adjust the indexing ring.)  edit : The Tommy Tompkins video below shows these screws on the Dewalt at the 9:00 minute mark.


That said, the last time I put on a new table I did it in a manner similar to Willian Ng’s video on the five cut method.
https://m.youtube.com/watch?v=UbG-n--LFgQ

  Background my 7740 and my 7790 had/have angle cleats that attach to the sides of base and the table is screwed onto  that.  The MBF had a series of through bolts that are adjustable to cleats on the base.  I hate those bolts so the first thing I did was got some angle.  The angle have a series of holes that will have screws driven through and into the table.  The only holes I am interested in when first installing a new table are the two closest to the fence, one on each side of the base.  
New Table
1. Table, fence material, calipers, 2- 2’ clamps, a few stout c-clamp, a couple of 1x2 about six inches long cut to 45° point,  squarish board about 14” long, framing square, scrap styrofoam
2. Make sure the arm is engaged in the 90° indent and the clamp is engaged Check for any wobble or play.  Fix that.  If you can’t fix that, then make all your adjustments with the arm to the extreme right of the wobble/play.  The saw may always have that play, but the amount of play will always be consistent. By always doing stuff to the same direction  of the play you will account for it and the net effect is that there is no variance.  Lay the table on the angles
3. Raise the blade a hair above the table, Rotate the saw to the rip position and get it close to the zero on the rip scale
4. Slide the table about even with the blade, rotate the blade back to the cross cut.
5. Use the framing square to align the table perpendicular to the face of the blade. Check it by pulling the saw down the leg of the framing square. Keep adjusting till it looks good. Clamp it down to the angle iron with a couple of c-clamps. You’re close
6. Clamp the fence material to the front table with the long clamps. Check to see if the fence lines up with the zero mark.  clamp the pointed stick to the saw base  with the point against the back of the fence as close as you can to the blade without interfering with its travel, this is your pivot reference.
7. Plug in you saw, cover your table with the styrofoam, raise the saw just a little less than the height of your styrofoam insulation board, (you don’t want to make any kerfs in your table till it’s accurate), get your squarish board. 
8. Make your cuts as in the Ng video
https://m.youtube.com/watch?v=UbG-n--LFgQ
9.From the measurements of the last off cut, figure out which way you need to adjust your fence, and about how much. Place the other pointed piece of 1x2 (piece B) against the corner that will need to come towards you and clamp it.
10..Loosen the clamps holding the table to the angle, use playing cards against the point of block B as shims to adjust the table.  Clamp it down.  Go to #7.

When the table and the fence are square to the travel of the saw, screw it to the angle cleats.


To adjust the table to be parallel to the travel of the saw. Cut the head off a #8 machine screw (to be used as a feeler gauge).  Inspect it to make sure it is relatively straight.
1  remove the blade and rotate the saw so the arbor is facing down, 
2  loosen the bolts holding the angle to the base just a tad; you want to be able to move the table up and down, but not without some force.
3 move the cleats as low as they go without stressing the table.  Identify the one that seems to be the highest of the low.  
4 release the arm clamp and swing the arm over that identified bolt. Engage the clamp. (Edit: Pull the motor directly over that identified bolt. ) Place the machine screw on the table under the arbor.  Lower the saw till the molecules of the arbor just barely almost touch the molecules of the screw. Tighten just a tad.
5 disengage the arm clamp Go to the other bolt of that cleat.  Raise that corner of the table till it clears the screw as in step 4 (see edit) ,  Eakes suggests a crescent wrench with the fat side wedged between the attaching bolt and the bottom of the table will lift the table a hair, at the same time as tightening the bolt some.  (Edit! DO NOT RAISE OR LOWER THE MOTOR ANY MORE. ONCE YOU SET IT FOR THE FIRST BOLT IT STAYS THAT HEIGHT. Sorry, I was not clear on that)
6 Go to the bolts on the other cleat and adjust as before.
7 After the table has been adjusted over all 4 bolts, check again as moving one corner may have affected another.  I usually went through 3-4 iterations before I was satisfied. (But I used a dial indicator, not a screw, and I thought I could get that last .003 if I just tried a little harder...).


Sent from my iPad
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#19
  Re: Radial Arm Saw Help by RPE1 (I just bought a used...)
Thank you all for your responses.  I'll get it cut an put together.  I'm  glad I asked for help.

RP
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#20
  Re: RE: Radial Arm Saw Help by RPE1 (Thank you all for yo...)
(06-02-2019, 08:39 PM)RPE1 Wrote: Thank you all for your responses.  I'll get it cut an put together.  I'm  glad I asked for help.

RP


If you haven’t started yet consider the Mr. Sawdust style table.
Everything is referenced from your table...the fence,  all the adjustments, the alignment, and all your stock. A flat, square, reinforced table, covered with a sacrificial top will last your lifetime.

Here are a couple of excellent videos on the ras tables by Brian Weekly, a member of the Dewalt RAS forum.

https://m.youtube.com/watch?v=Q1cc-_vPT0w

https://m.youtube.com/watch?v=_e5yQC_i7mI

Here is a video on constructing a Mr. Sawdust table by Tommy Tompkins. You can see the angle cleats for table attachments at the 6:15 mark, about 40 seconds later you can see them mounted on the saw. Each has 5 screw holes for table attachment and2 elongated holes for attaching to the saw base and height adjustment.
https://m.youtube.com/watch?v=6TMBT45g_qg
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