# Radial Arm Saw Cutting Problem



## dave247 (Oct 17, 2010)

All,
First time posting a question, although I've found quite a bit of helpful information on these pages. I'm a do-it-yourselfer and am pretty handy with tools, but do not consider myself an accomplished woodworker (yet).

Like many others, I picked up a serviceable 10" Craftsman radial arm saw for $150 at a garage sale and searched this forum for info on how to clean it and tighten it up. Just received the recall kit referenced in several posts here (THANKS!), and dragged my old TV out to the shed today to keep an eye on the game while I replaced the table top and installed the new guard. As part of the process, I leveled the surfaces and re-checked everything with a new framing square. The blade is perpendicular to the table top and fence, and the blade tracks right along the framing square from back to front along the entire length of travel.

The problem occurs when I cross-cut boards. When I pull the blade through the board (no matter what width or thickness), it still "rounds off" the upper corner of the board on the left as the blade clears the board. It is almost as if the trailing edge of the blade suddenly kicks left as it comes through the board. The board is cut square, except the upper front corner is rounded off as if I hit it with a sander.

I'm using a decent quality DeWalt blade that I used briefly on my table saw without any problems, so I don't think I'm getting any wobble since I can manually rotate the blade and the teeth just barely brush the edge of the framing square. The roller assemblies on the trolley part of the arm were loose and the whole thing wobbled badly when I got the saw, but I found the procedure in one of the forums to tighten it up, and now they are snug and require an even force to pull the saw through it's complete travel. I tried applying different amounts of force on the handle as I pulled it through different boards, but didn't see any evidence that I was muscling the thing to one side or the other. At this point, I'm stumped...

Any advice and suggestions are greatly appreciated!
Thanks!
Dave


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## rrich (Jun 24, 2009)

Dave,
It sounds like the blade is not parallel to the line of travel. What you need to do is with a framing square against the fence adjust the blade to be perpendicular to the fence. On the left side of the carriage there are two roller guides that ride on the arm. As I recall, these are on an eccentric and allow the adjustment. You will have to do a tighten / loosen process on these roller guides on both sides of the motor yoke that rides on the arm.

WARNING - The bolts mounting the roller guides screw into aluminum. Over tightening can pop the threads out of the aluminum. This will not be apparent until after rotating the yoke into the rip position and return. On my RAS I was getting rip kick backs and rough cross cuts until I found the problem. ATT I ordered a new part from sears but the one that they sent had a hole too small for the yoke locking pin. When I called sears parts they told me "Not our problem."


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## cabinetman (Jul 5, 2007)

*WELCOME TO THE FORUM*

You might check the carriage lock. That's the lever that when pushed to the left loosens the carriage and the carriage will swivel (turns the motor/blade parallel to the fence). When pushed to the right it tightens the carriage. It could have debris on the parts that keep it from tightening completely. 












 





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## dave247 (Oct 17, 2010)

Rich,
Thanks for the quick response. This unit was really sloppy when I first got it, and I ran through that adjustment a couple times until I got it tight enough to stop the side-to-side wobble. The blade seemed to be almost dead on when I checked it today against the framing square and fence at about the midpoint of the travel, but I'll give it another shot and re-check it at different points in case I missed something. 
Dave


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## woodnthings (Jan 24, 2009)

*Also check the blade/arbor*

For runout by spinning the blade against a wooden block rather than you framing square clamped to the table and watching and listening for the tooth contact. I don't know what the tolerance should be, but it will show if it's way out of "whack" (technical term for screwed up). Try putting the blade on at 90 degrees to the previous mounting to see it it goes away or is magnified. This will be easier and faster than rich's suggestion to try first. JMO bill
Also "bump" the arm right to left to see if it takes a new setting easily. The locking detent may need some TLC?


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## dave247 (Oct 17, 2010)

*Back again, no luck*

All,
Many thanks for the advice. Finally got some time to head out to the shed and try your suggestions. Unfortunately, still no luck resolving the cross-cut problem. 
Since last time, I went through all of the advice and have the following results:
1. Re-checked blade alignment and it is perpendicular to the table and the fence. Framing square makes contact across the entire face of the blade. 
2. Re-checked the roller guides and they are snug, with no wobble or side-to-side movement along the entire travel. 
3. Re-checked the carriage lock, and it is really tight and locks solidly. 
4. Checked the radial arm itself and did find a little lateral movement when locked on zero, so I snugged the socket head screws on the big upright arbor shaft until it locked solidly, then checked the blade to make sure it still tracked right along the complete path of travel and re-zeroed the miter indicator dial.
5. Swapped blades and checked run-out as suggested, and virtually every tooth ticks against the wood block.
Once all of these items were checked, I found the trailing edge of the blade still seems to be pushing left, and rounds the top front corner of any width or thickness board. BUT, when I started the cut from the front of the table, it makes a perfect cut when pushed through the board. When I saw that, I re-positioned the board, made another cut from the rear and got the usual rounded front corner as expected, then pushed back through without moving the board. It cut off the rounded corner and continued to cut straight to the back with no rounding and had a perfectly square edge. 

After making a number of new cuts, it appears the blade is pulling itself to the right when pulling the carriage, but cuts straight when pushed to the rear through the board. When I put the framing square on wider boards, the end is not quite square on pull cuts, but the cut is perfect when pushed. I even tried muscling the carriage to the left when pulling, but it still tracks to the right when cutting. Double checked alignment with no power applied, and the blade tracks straight along the square going both ways. Clearly, I'm missing something...

Again, any advice is greatly appreciated! 

Dave


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## Cajuncypress (Oct 25, 2010)

I'm thinking it's probably your blade. You mentioned that it was a blade that came out of your table saw. The angle on radial arm blades are not the same as those on table saw blades. Blades made for radial arm saws actually have a negative hook angle. The blade you are using is probably too aggressive for your saw and may be pulling the carriage off of square as it clears because there is no longer enough material for it to bite.


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## woodnthings (Jan 24, 2009)

*How about this?*

On some saws the carriage can be removed from the sliding arm without unhooking any wiring or worst case just remove it and leave it on the table still wired up. Then remove the 2 hardened rails that the carriage slides on and examine them for wear, straightness and if possible flip them right to left and or end for end to put some new surfaces in play and then reinstall them. See if the condition persists or has moved to the right side.
This is a simple task and is worth a try. 
You might also try twisting the carriage on the rails to see how much play there is in the roller bearings. They are adjustable on cams if I recall, if necessary. 

You don't really want to be using the saw in a "push" mode since the first teeth contacting the workpiece will tend to lift it off the table rather than push it down as in the "pull" mode. 

Let us know what happens!  bill


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## dave247 (Oct 17, 2010)

Thanks, Cajuncypress. I didn't know there was any significant difference between blade hook angles for table, miter or RAS. I'll run by Sears sometime this week and look for one specifically packaged for radial arm saws. If I don't get anything else out of this, at least I've become intimately familiar with the saw and learned how to perform all the tune-up procedures on the saw! 
Dave


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## woodnthings (Jan 24, 2009)

*I don't think it's the blade*

Or it wouldn't just happen on the left side of the workpiece. Negative hook blades have been used on miter saws for quite a while now and are a good choice for RAS too. But a standard "tablesaw" blade will work just fine, it just "self feeds" if not restrained by a firm grip on the handle and a little resistance. By all means get a new blade for safety reasons and a smoother cut, but I don't think it's the source of your issue.  bill


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## rrich (Jun 24, 2009)

woodnthings said:


> For runout by spinning the blade against a wooden block rather than you framing square clamped to the table and watching and listening for the tooth contact. I don't know what the tolerance should be, but it will show if it's way out of "whack" (technical term for screwed up). Try putting the blade on at 90 degrees to the previous mounting to see it it goes away or is magnified. This will be easier and faster than rich's suggestion to try first.


A good suggestion...

Also clamp something as a reference to the table top that almost touches a tooth of the blade. Then turn the blade by hand and see if there are any teeth bent out toward the reference. All it takes is one tooth to make the cut as rough as though a chain saw was used.


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## Gary Beasley (Jan 21, 2009)

Sounds like wear some where causing it to rock sideways a bit with cutting pressure. Have you tried clamping a board in the path of the blade and pulling it in contact with the power off to see if it rocks on contact? It sounds like the cutting pressure is holding it square and cutting through releases the pressure and it rocks over and buzzes the end of the cut.


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## dave247 (Oct 17, 2010)

*Clarification, Please!*

Gary,
I'm ready to give it a try, but want to make sure I understand what you mean by "pulling it in contact with the power off to see if it rocks on contact." Do you mean to clamp the board so the squared end is in line with the blade's line of travel and slightly mis-aligned to the path as it moves forward along the edge of the board so the blade is pushed to one side or the other? 
Thanks!
Dave


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## Gary Beasley (Jan 21, 2009)

No, just push straight into it and watch closely to see if the blade deflects any. That would be slack somewhere, for instance in the motor it could deflect if there was slack in the bearings.


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## woodnthings (Jan 24, 2009)

*There is some play somewhere*



woodnthings said:


> On some saws the carriage can be removed from the sliding arm without unhooking any wiring or worst case just remove it and leave it on the table still wired up. Then remove the 2 hardened rails that the carriage slides on and examine them for wear, straightness and if possible flip them right to left and or end for end to put some new surfaces in play and then reinstall them. See if the condition persists or has moved to the right side.
> This is a simple task and is worth a try.
> You might also try twisting the carriage on the rails to see how much play there is in the roller bearings. They are adjustable on cams if I recall, if necessary.
> Let us know what happens!  bill


It has to be in either of two places , the slide rails, loose or worn possibly, or the rollers that "capture" the carriage on the rails which are adjustable. That's it.... IF.... the carriage is locked securely and the arm is locked securely. If not you have the mystery saw of all times in which case Craigs List it and get another one.  bill


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## dave247 (Oct 17, 2010)

Bill, I'm afraid you're right. I've just been putting off tearing apart the arm until I've exhausted all other options. I've already tightened the cams on the rollers to the point where it eliminates any rocking or lateral movement, but that makes it hard to pull the carriage, and it still does it. It's also a one-piece track made from a box-style beam, so I won't be able to swap bearing tracks around, only check for problems with the outer bearings and the track surfaces themselves (this has two "V" rollers in the center of the carriage that engage a ridge down the center of the one-piece track assembly, and two outer ball bearing rollers on the outside that ride on the track's bearing surfaces on either side). Will let you know what I find when I get it completely opened up, cleaned and re-assembled. Thanks again to you and the others for all of the ideas and advice.
Dave


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## dave247 (Oct 17, 2010)

*Problem Solved*

All,
Finally got time to work on the problem today and got it cutting straight--determined it was a combination of issues. Found a bit more play in the arbor shaft column and carriage--just enough to let it wander a bit. Also found the blade alignments looked good when the square was right under the blade, but opened up a slight angle as the carriage moved forward, both with the table surface and the fence, so the blade was actually cocked slightly. Went back to square one and checked/tightened everything, and re-did the complete alignment process, only this time I repeatedly went back and re-checked each alignment after doing the next one, and found some interaction between them that I hadn't noticed before. Finally got the blade perfectly square along the entire travel of the carriage and really tightened down the screws to eliminate any play in the arbor shaft and carriage/blade. It takes even more effort to lock/unlock things, pull the carriage and crank up the arm now, but at least this old saw is cutting perfectly square. Guess you could say it was a combination of worn and sloppy hardware, and sloppy aligning on my part.
Again, many thanks for all the advice and patience. 
Dave


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## sedaphina (Jul 21, 2013)

Thanks to everyone who chimed in on this post. I just got a Craftsman 9" radial arm saw, and it's doing the same thing as Dave's (although I am not sure about the difference in pushing versus pulling the carriage). One edge is definitely rounded off. I'll test it again today on another project and apply everyone's suggestions, starting with a new blade. There's no telling how old this one is.

Seda


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## Centered one (Apr 20, 2020)

sedaphina said:


> Thanks to everyone who chimed in on this post. I just got a Craftsman 9" radial arm saw, and it's doing the same thing as Dave's (although I am not sure about the difference in pushing versus pulling the carriage). One edge is definitely rounded off. I'll test it again today on another project and apply everyone's suggestions, starting with a new blade. There's no telling how old this one is.
> 
> Seda


I am surprised you can find blades for the nine inch RAS. I inherited one and used it until the blades were no longer available. It was light enough to take on some construction jobs, and seemed much tighter than the electronic RAS version carriage style.


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## Tom-G (Nov 11, 2012)

This is an old thread from 2010 & 2013. 

However, Freud makes 9” blades (and maybe a few others make them too). You would need to check with them to see if any have the proper tooth geometry for a RAS.


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## woodnthings (Jan 24, 2009)

*Surprized.. ...did you Google for them?*

I did a G search and found these;
https://www.google.com/search?client=firefox-b-1-d&q=radial+arm+saw+blade+9"


:surprise2:


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