Can't make square bevel cut using Radial Arm Saw

[Steve Muccione]

Hi guys, I think I’m way out of my league in these forums but I’m hoping someone will help me out. I’m a retired EE pushing 70yrs old. I bought a used radial arm saw a few months ago for $100.00. It seems to be in good shape but I cannot get the bevel to square up. See pics:

http://i175.photobucket.com/albums/w127/Genietto/Saw/DSCN1247.jpg

http://i175.photobucket.com/albums/w127/Genietto/Saw/DSCN1249.jpg

http://i175.photobucket.com/albums/w127/Genietto/Saw/DSCN1250.jpg

http://i175.photobucket.com/albums/w127/Genietto/Saw/Saw4.jpg

I’ve got really good mechanical skills but I cannot determine the cause of this error. Obviously the motor assembly is moving during the cut but the slop (play) between the various components and bearings seems minimal and normal to me. I’ve eliminated the blade(s) because I’ve tried several and all cut true on my table saw. I've tried 3/4'oak, pine and plywood with same result.

I moved the blade slowly, about 45 seconds to complete the cut and with minimal pressure applied.


If I compensate for the error by setting the saw at -2degrees, the result is a concave arc.

Is this normal for the is brand saw?

I'm far from being a skilled craftsman but...

I’d appreciate any suggestions - Steve

[Lou Ferrarini]

Steve,

I have an older saw similar to yours and the only thing I can think of is that the lock for the bevel adjustment might be loose. Do you have the manual? I would go through the entire alignment procedure for the saw. Mine has a lever that locks the bevel adjustment. If I remember, this can be adjusted for tightness. Good luck.

Edit in: Also, the tracks that the motor rides on could be worn or the wheels could be loose causing the motor to shift when pulled through the wood. If the tracks are not worn too bad, there is an adjustment to tighten this up also.

[Jeffrey Makiel]

Steve,
I have a radial saw very similiar to your model (same model but no electronics). Lou gives some good advice.

It should be noted that our model saw (circa late 1980s to early 1990s) was of a poor design to begin with. Sears stop making this saw because of complaints and reverted back to an earlier early 1980s design. One issue was the way the head was supported to arm via poor bearing arrangement resulting is some slop.

As for me, I've downgraded the use of my saw to rough crosscut of long stock, and accurate crosscut of stock no wider than 3" and no taller than 1".

-Jeff :)

[Kelly C. Hanna]

Have you tried moving the table? 9 out of 10 times the tables on these old RAS's were never mounted properly. A simple shim would solve that in a heartbeat.

[Richard Niemiec]

What Lou, Jeff and Kelly said. I have an old Sears RAS, different model, but it never satisfactorily held its alignment so I too keep it around only for rough work. Pay particular attention to the table top leveling procedure; mine had a series of screws but your's could be different. That table is not original, and could have lacked the adjustment screws that are essential to getting a flat surface registered to the rest of the saw.

I recently restored to operation a DeWalt RAS built in 1953, and let me tell you the difference is amazing. They can go for a song, I paid $50 but it was all rusty (surface) and siezed up from sitting in someone's back yard under a tarp for a couple of years, but it now runs like a champ. I had to build a new table, and that was the one key item in my view, and once I finished adjusting the saw to the table, its dead on. This table adjustment procedure is specific to each type/mfgr of the saw and the stand, so see if you can get the original manual for the saw, the OWWM site may help. Good Luck. RN

[Richard Niemiec]

Steve: I forgot to mention that if you give up on trying to make this saw work properly, you can get $100 for the motor through a recall of RAS's made by Emerson for Sears. Check out : radialarmsawrecall.com and see if your SN matches the recalled units. Alternatively, you can get a new guard and table top for your unit. Personally, I'd look for a DeWalt and get my investment back on the Sears unit. RN

[Paul Simmel]

>>> If I compensate for the error by setting the saw at -2degrees, the result is a concave arc.

That blade looks really raunchy and I’d still suspect it unless you ran the piece through the TS in the same way. The only way you could have an arc is if one side of the teeth is sharper, or it is severely warped.

Also, 45 seconds to pull through that piece is ridiculous. Should be done in just a few seconds max.

[Howard Acheson]

Do you have the instruction manual? RAS's require that they be aligned in a specific order. Each step in the alignment requires that the prior step be completed.

If you don't have the manual, you can get general instructions from the Wood Magazine site at: http://woodstore.net/tunupyourpow.html

[Ray Bersch]

Steve, I had a similar saw that I bought new and could not get to work from day one. I held onto it for years with nary a cut being made - when I retired and started the woodworking thing in earnest I vowed to buy a new saw - problem was what to do with the old one? I could not in good conscience sell it to anyone without full disclosure - even for fifty bucks - so when I found out about the recall I jumped on it immediately - to get the $100 rebate you have to send the motor back to the manufacturer - when I took the saw apart it looked brand new - no matter, the motor went back and the rest of it went out and I moved on - the bad memories linger however, and my advice would be to deep six the thing and start over.

Ray

[Art Walker]

I believe that *at the least*, the blade is toed in or out (automotive terminology) relative to the arm. For whatever reason, this is called heel when applied to a saw. The portion near the top of your workpiece is being swept by both the leading and trailing edges of the blade, whereas the bottom is cut only by blade more or less directly below the spindle. If I'm right, then if there were motor clearance for a full height cut, the remnant on the R side would also show a gap at the top if held to a square in mirror-image of the final photo, and concave edges would be expected according to the trig. The cut shown seems so far off that a dial indicator may not be needed to demonstrate/illustrate the heel: if a fine object can be held fixed so as to just touch the left-side plate of the blade near its leading edge just far enough above or below the motor for the collar and arbor nuts to pass, and then the carriage is drawn forward (motor off, blade held fixed if you're convinced it has very little runout), either a gap will appear or the object will be pushed leftward depending on whether the toe is in or out. This heel may emerge from misalignment of the yoke on the carriage, or at the motor's capture in the yoke, or both. There should exist adjustment mechanisms built into both of these degrees of freedom for purposes of alignment, but I don't know your saw well enough.

Whether I'm right or wrong, the best next step is to find an adequate written alignment procedure for your saw, and follow it. The book "Fine tuning your Radial Arm Saw" by Jon Eakes is the most complete, and he treats Delta, DeWalt, and Craftsman saws in parallel so deals with many of the differences (to be fair, the particular craftsman model he uses is not your model, but still...). It's out of print but can be found used, and the author sells a pdf for $15 online. "The magic of your radial arm saw" by de Cristoforo and "Radial Arm Saw Techniques" are great RAS books but have only 6 pages explicitly on alignment procedures, which is not as much as most original owners manuals - many of which are available as PDFs at owwm.com if you can't get it for yours from Sears Parts Direct.
For this work, a dial indicator and a stand to hold it will be essential; even the cheap ones from harbor freight are up to this task.

A flat table, with a back edge orthogonal to the arm, is important for complete RAS alignment and good results in practice; but the cut you've shown doesn't really depend on it. That is a later bridge.

[Steve Muccione]

Wow! This forum gets a lot of posts in one day. I had to do a ‘search’ to find my thread. Thanks to you folks I now know the cause of the problem. If I had followed a procedure it probably would have been a non-issue.

Mr. Walker was on target when he deemed it to be a “toe in” problem. I found the motor shaft not to be perpendicular with the line of cut i.e., rotated slightly clockwise when viewed from above (not noticeable but measurable).]

I may not keep this saw because I like the idea of rebuilding an oldie but goodie; E-bay here I come.

The saw tabletop started life as a kitchen island countertop. I’m using it to rough in the alignment. I know the fence is true for its entire length and exactly perpendicular to the normal cut line. The tabletop has some undulations, but none that could have influenced my problem. The top will be scrapped when I fit the saw into my workbench (if I keep it).

Grazie, grazie signori.:)

[Joe Jensen]

Hi guys, I think I’m way out of my league in these forums but I’m hoping someone will help me out. I’m a retired EE pushing 70yrs old. I bought a used radial arm saw a few months ago for $100.00. It seems to be in good shape but I cannot get the bevel to square up. See pics:

http://i175.photobucket.com/albums/w127/Genietto/Saw/DSCN1247.jpg

http://i175.photobucket.com/albums/w127/Genietto/Saw/DSCN1249.jpg

http://i175.photobucket.com/albums/w127/Genietto/Saw/DSCN1250.jpg

http://i175.photobucket.com/albums/w127/Genietto/Saw/Saw4.jpg

I’ve got really good mechanical skills but I cannot determine the cause of this error. Obviously the motor assembly is moving during the cut but the slop (play) between the various components and bearings seems minimal and normal to me. I’ve eliminated the blade(s) because I’ve tried several and all cut true on my table saw. I've tried 3/4'oak, pine and plywood with same result.

I moved the blade slowly, about 45 seconds to complete the cut and with minimal pressure applied.


If I compensate for the error by setting the saw at -2degrees, the result is a concave arc.

Is this normal for the is brand saw?

I'm far from being a skilled craftsman but...

I’d appreciate any suggestions - Steve

Steve, I have an industrial Dewalt RAS. That saw has an adjustment for what they call "heel". Try the OWWM website and search for a manual online. That manual has very clear instructions on how to adjust all aspects of a RAS to get a perfect cut. I'd start there....joe

[Randall Frey]

I too have that saw, I have never been able to get it to cut straight with any consistently. (I have aligned it over and over) It now sits over at Mom's collecting dust. I must say, your picture cutting a piece that tall with a fence that short is a recipe for disaster. Don't ask me how I know this but let's just say it was lesson #1 that these machines can do some damage. You do have it clamped but still beware.