The Forestry Forum

Other topics for members => General Woodworking => Topic started by: SlowJoeCrow on March 15, 2017, 04:43:04 PM

Title: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 15, 2017, 04:43:04 PM
I am considering buying a large Delta radial arm saw, but I am not an electrical whiz and I can't tell if the motor is 3 phase or not.  This is a Delta International 33-420 that was originally bought new in the 1990's and used until 2004 and it has just been sitting in a warehouse since.  Upon inspection, I couldn't find a motor plate with the specs - looking online at similar vintage machines, it appears the motor tag was just a decal so it could have peeled off.  After more internet research, it also appears that this model saw was available with different motors, both 3 phase and single phase.  The data decal on the lower saw frame indicates that it is 3 phase, but the fellow selling it says he's pretty sure it was single phase since they didn't have 3 phase power at the time the saw was purchased.  He is an employee of the larger company that owned it and isn't certain.  How can I tell what kind of motor this sucker has???  Anybody knowledgeable about these saws or what to look for to tell? I was ill-equipped at the time that I looked at it and will likely go back and open up the motor top plate for more inspection.  Here is the data plate that is one the lower frame of the saw.
(https://forestryforum.com/gallery/albums/userpics/44509/20170315_130023.jpg?easyrotate_cache=1489610469)

Thoughts anyone?
Title: Re: Delta 18" Radial Arm Saw
Post by: 21incher on March 15, 2017, 04:53:25 PM
It says 3 phase on the sticker. Check the number of wires to be sure ( there will be 3 hots). You should be able to run it on single phase with a VFD or phase converter.  :)
Title: Re: Delta 18" Radial Arm Saw
Post by: Darrel on March 15, 2017, 05:18:40 PM
Hear is a link that goes into detail as to how to build a rotary phase converter. It is way easier than most people believe

http://www.metalwebnews.com/howto/ph-conv/ph-conv.html
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 15, 2017, 06:11:05 PM
I will be going back tomorrow to open the motor cover to look at the wires.  They were pretty adament that it was single phase despite the label shown above.
Title: Re: Delta 18" Radial Arm Saw
Post by: Dave Shepard on March 15, 2017, 06:29:42 PM
That O with a slash through it means phase, in this case three phase. Could the motor have been replaced with a single phase one?
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 15, 2017, 09:07:20 PM
That what I was wondering.   They said they bought it new though so they would have had it equipped for whatever electrical service they had at the time.
We shall see tomorrow.   I'm hoping it is the 5 hp single phase on the machine.
Title: Re: Delta 18" Radial Arm Saw
Post by: Larry on March 15, 2017, 10:24:30 PM
The label say's its a 3 phase motor so I suspect its 3 phase.  It can become tricky.  In the picture is a 14" Delta bandsaw that has a 3 phase motor that I run on single phase.  Inside the box is a small capacitor and relay that starts the motor.  Its called a static phase converter.  Most folks assume the bandsaw is single phase.

I built that static converter, but I never would run a 5 HP saw with one, especially if I was working it hard.  I also build rotary phase converters which work well and have a whole flock of VFD's in the shop.  VFD's to run 5 HP are expensive.

And remember....Real Machines are three phase. :)

(https://forestryforum.com/gallery/albums/userpics/10125/DSCF9382.JPG?easyrotate_cache=1489630783)
Title: Re: Delta 18" Radial Arm Saw
Post by: opticsguy on March 16, 2017, 11:28:09 AM
18" radial arm saw?  Never knew they made such an item, I want one!!!!!!!!!!!!!!!!
Title: Re: Delta 18" Radial Arm Saw
Post by: WV Sawmiller on March 16, 2017, 01:03:54 PM
Quote from: opticsguy on March 16, 2017, 11:28:09 AM
18" radial arm saw?  Never knew they made such an item, I want one!!!!!!!!!!!!!!!!
X2.

   I just got a 10" radial arm saw last year, built a stand/table for it in the end of my lumber shed and I don't know how I ever got along without it. I see I now salvage a lot more short lumber and such that I used to throw in the scrap pile. My next tool to use more is my planer.
Title: Re: Delta 18" Radial Arm Saw
Post by: Brian_Weekley on March 16, 2017, 02:51:27 PM
Any chance it already has a phase converter on it but they didn't realize what it was?

Make sure you wear your big boy pants to move that thing!  Radial arm saws are cool!

BTW, this is a fascinating WWII era film showing large scale use of DeWalt radial arm saws to build barracks.  The versatility of these saws are amazing...


https://www.youtube.com/watch?v=HiGH0Qsu3ak
Title: Re: Delta 18" Radial Arm Saw
Post by: Dave Shepard on March 16, 2017, 07:15:26 PM
The scale of those projects is amazing. I'm doing good just to make a few tomato stakes in an hour. :D
Title: Re: Delta 18" Radial Arm Saw
Post by: Brian_Weekley on March 16, 2017, 07:40:54 PM
½
Quote from: Dave Shepard on March 16, 2017, 07:15:26 PM
I'm doing good just to make a few tomato stakes in an hour. :D

Did you see them making tomato stakes at 13:15 in that video?   :D

And check out the dado blade at 21:15!
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 16, 2017, 08:12:05 PM
Well to give an update, I returned for more investigation... it is in fact a single phase motor - there are  two capacitors in the box on top of the motor.  From the research that I have done, the 33-420 was a 5hp single phase.  The 33-421 was a 7.5hp 3 phase.  I have no idea why the model plate indicates it is three phase,  the motor is definitely single phase, and looks completely stock as far as I can tell.  I will post some photos if I can.
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 16, 2017, 08:54:47 PM
Wow that video is awesome!!  BTW, cutting points on stakes is exactly why I want one of these larger radial arm saws, even though I have never seen this video before.  Nice to know my thought process isn't way off!  I want to be able to tip entire boards and then rip them into stakes.  The saw that I'm looking at is in rough shape though and I'm having second thoughts.   I have no way of seeing it run before purchasing and I don't know what condition the motor is in.
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 16, 2017, 09:15:05 PM
Here are some pictures of the beast:
(https://forestryforum.com/gallery/albums/userpics/44509/20170316_125812.jpg?easyrotate_cache=1489712276)
(https://forestryforum.com/gallery/albums/userpics/44509/20170316_125803.jpg?easyrotate_cache=1489712338)
(https://forestryforum.com/gallery/albums/userpics/44509/20170316_122529.jpg?easyrotate_cache=1489712410)
The last picture shows the motor capacitors.   It is in rough shape with the stock legs missing, the brass Arbor nut stripped out and most pivot points are seized up.
Title: Re: Delta 18" Radial Arm Saw
Post by: Larry on March 16, 2017, 09:29:28 PM
In that condition its hardly worth scrap value.  Usually the motors are good and at most would require new bearings which is simple.  The arm is the real problem.  I've never tore into a Delta but some of the Dewalt arms can be re-done at great expense.

I've seen a lot of RAS's at industrial auctions that do good if they get a bid.  I have a 12" Delta and a 16" Dewalt in fair condition but lots better than that saw.  Think I have $100 in the two of them.

Title: Re: Delta 18" Radial Arm Saw
Post by: Darrel on March 16, 2017, 10:04:30 PM
A machine in that condition will be happier if you don't wake it up and make it go to work and so will you. I'd hold off 'till I found one in better condition. I know of no woodworking machine as versatile or dangerous as a RAS. that being said, use your head and you can stay quite safe.
Title: Re: Delta 18" Radial Arm Saw
Post by: Don P on March 16, 2017, 10:38:03 PM
I've used older versions of that saw in 3 ph, they are beasts, one followed me around to 2 different shops, couldn't get away from it  :D.
I was working in an expanding furniture company back in the day... Yes back in the day there were expanding furniture companies. They had about 30 12" DeWalt radial arms that I helped switch out to whirlwind chop saws. The problem with most was that the arm is a casting with grooves machined in it that the motor carriage bearings run in. Those grooves were pretty heavily worn on most of the saws in the first 6" or so where they did most of their work and bouncing. The Craftsman's had a half round strip of replaceable steel and bearings with a concave rather than convex outer profile performing the same function on their saws. I agree a radial arm is probably the most versatile and dangerous tool in the shop.
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 16, 2017, 10:53:56 PM
The arm and slider are in good shape, just needs cleaned and relubed.  This Delta has four roller bearings that ride on four hardened rods held in the cast arm.  If these wear, all you have to do is rotate the rods.  I'm sure I could loosen up the pivot points as well, I'm more worried about the motor being junk.  I am leaning away from it since I would have to spend a good amount of time to get it up and running and my time is at a premium.  He is asking $400.  Still, it's not everyday I come across a single phase 18" RAS......hmmmm....
Title: Re: Delta 18" Radial Arm Saw
Post by: 21incher on March 17, 2017, 08:32:58 AM
Good luck if you purchase it. For $400.00 I would have to hear the motor running. I bet it will cost another $400.00 for a good blade with the proper hook angle for it. That saw would put fear in my heart after seeing my 10 inch kick out a strip of wood that shattered when it hit the concrete wall. :) 
Title: Re: Delta 18" Radial Arm Saw
Post by: Don P on March 17, 2017, 08:52:36 AM
It's in a shop with lights? Roll it over to the panel and wire it into a breaker for a trial run. The black capacitor looks like a start, the metal cap a run.
Title: Re: Delta 18" Radial Arm Saw
Post by: thechknhwk on March 17, 2017, 10:32:41 AM
I watched that video yesterday and those saws are awesome.  I want that 24"er.
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 18, 2017, 07:26:33 AM
Well I don't have to worry about whether I should buy it...somebody else bought it and I am OK with that.
Title: Re: Delta 18" Radial Arm Saw
Post by: Kbeitz on March 18, 2017, 07:03:30 PM
Just remember that a radial arm saw takes a zero pitch blade.
Try something different and you might be laying on the floor.
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 18, 2017, 09:15:45 PM
Yes sir, zero or negative 5.  That is what I used in my Crapsman 10" RAS before I sold it.  It's funny, I went from RAS to SCMS and now I am looking to to back.
Title: Re: Delta 18" Radial Arm Saw
Post by: Darrel on March 19, 2017, 12:53:59 AM
Happy birthday SlowJoeCrow!
Title: Re: Delta 18" Radial Arm Saw
Post by: Solomon on March 19, 2017, 08:55:07 PM
I saw a 14 inch delta  RA   for $125.00 on a woodworking forum, I can't remember witch one now but , arm saws are for sale everywhere and cheap,  If it were me, I'd shop around before paying 400 for it.   If you don't absolutely have to have an 18 inch RA, you might do well to shop around and find a 16,14,or 12 inch saw in good working order that's single phase.    Plug and play !! ???
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on March 20, 2017, 07:40:52 AM
Yep, I don't need a 18".  Ideally I want a 14" with a single phase motor.  I'm sure I will find one, just a matter of time.  I was bidding on an older Delta Multiplex 40-B a couple of weeks ago that would have been perfect, but I let it slip away on accident...whoops!
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on May 31, 2017, 10:53:28 AM
Well, I went smaller, quite a bit smaller.  I just picked up a Delta 12" radial arm saw, a 33-890.  I think it will work for want I want to do with it.  It has the 2 hp 230v motor.  This saw was bought by a lady on recommendation of her live-in boyfriend at the time and then never used.  It might have cut wood like twice.  Maybe three times.  It has the factory delta blade on it (non-carbide teeth) which is still sharp.  The original mdf table and fence has NO SAW KERFS IN IT!

I am currently going through the adjustments and will post some pictures soon.  Eventually the table will need replaced as it is bowed from time but my immediate use for it isn't precision woodworking so I will let it go for a while.  I do have a proper new blade coming for it.  I am anxious to see the power difference between this saw and the 10" craftsmen that I used to own that claimed 2.5 hp (yeah right!)
Title: Re: Delta 18" Radial Arm Saw
Post by: Darrel on May 31, 2017, 01:24:05 PM
That should be a good saw and will serve you well
Title: Re: Delta 18" Radial Arm Saw
Post by: hackberry jake on July 24, 2017, 10:04:56 PM
Quote from: Larry on March 15, 2017, 10:24:30 PM


And remember....Real Machines are three phase. :)

(https://forestryforum.com/gallery/albums/userpics/10125/DSCF9382.JPG?easyrotate_cache=1489630783)
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on February 12, 2018, 09:39:56 PM

(https://forestryforum.com/gallery/albums/userpics/44509/20180212_165231.jpg?easyrotate_cache=1518489529)


Welp, today was a lucky day.  I cant understand why, but while this saw was running, the blade nut on the arbor shaft backed out and the blade dropped off the shaft at full speed, hit the table and came straight towards me.  It hit me right in the hip, glanced off and flew about 25' across the shop.  Very very lucky I didn't get hurt.  My Carhart coat saved me, the blade tore it up instead of my skin.  I think if I didn't have the coat on, it would have went through my shirt and pants and tore me up a bit.
Here is a picture of what it did to my coat.

(https://forestryforum.com/gallery/albums/userpics/44509/20180212_170619.jpg?easyrotate_cache=1518489142)
 
That's not all, after that close call, the start capacitor on the motor is toast all of a sudden.

I am still trying to figure out why the nut backed out and the blade came off.  It doesn't make sense to me.
Stay safe everyone!

Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on February 12, 2018, 09:58:06 PM
Is anyone familar with the motors on these saws?  The start capacitor is junk all of a sudden, it dumped the electrolite fluid out of it and started smoking bad after I tried to start it up again after the blade flew off.  It will start up but starts to smoke and spits fluid everywhere.  I was wondering if the capacitor went bad while the saw was running and that somehow jolted the motor and made the nut loosen up. 
I don't know much about capacitors, much here is pictures of both capacitors

(https://forestryforum.com/gallery/albums/userpics/44509/20180212_165313.jpg?easyrotate_cache=1518490362)


(https://forestryforum.com/gallery/albums/userpics/44509/20180212_165342.jpg?easyrotate_cache=1518490280)

It's the first one, the Phillips that blew.
Now I am questioning if that is the proper capacitor to begin with.  The saw is 230volt and the capacitor is 125 volt.  Can anyone educate me on this?
Title: Re: Delta 18" Radial Arm Saw
Post by: Kbeitz on February 12, 2018, 10:02:02 PM
My bet is for some reason the motor locked up.
That's why the nut came off the arbor shaft.
That would also be the reason the capacitor went bad.
The motor was trying to restart with a locked arbor.

Glade you din't get hurt.
Title: Re: Delta 18" Radial Arm Saw
Post by: Larry on February 12, 2018, 10:19:57 PM
I'm not sure what that motor uses, but the centrifugal switch or potential relay cuts the capacitor out of the circuit when running.  Like Kbeitz I think the motor had to come to a sudden stop for the nut to come off. 

Buy a lottery ticket....your lucky and I'm glad it was only a jacket.
Title: Re: Delta 18" Radial Arm Saw
Post by: Don P on February 12, 2018, 10:44:52 PM
Electric is black magic to me but that's what I was thinking, it almost sounds like it failed, kicked the cap in out of phase, stopped the motor and cooked. It won't matter if the cap is rated for higher voltage, the mfd rating should be the same. Very lucky!
Title: Re: Delta 18" Radial Arm Saw
Post by: Darrel on February 12, 2018, 11:12:55 PM
I'm thinking that I'd have that motor checked out by a qualified motor guru before I flipped the switch on it again. I'm thinking that the fried capacitor is just a victim of whatever the real problem is as you almost were.
Title: Re: Delta 18" Radial Arm Saw
Post by: samandothers on February 13, 2018, 10:38:25 AM
Man, close call.  Glad no blood and only torn material.
Title: Re: Delta 18" Radial Arm Saw
Post by: muggs on February 13, 2018, 10:51:05 AM
Yea I see lots of 220v motors with 125 v capacitors, you can replace it with a 220v cap. It will probably hold up longer. Like others have said, find out the reason it failed before you replace. A start cap can only be energized for about 3 seconds. A switch must take it out of the circuit. But sometimes they just fail after time.   Muggs
Title: Re: Delta 18" Radial Arm Saw
Post by: YellowHammer on February 13, 2018, 01:16:02 PM
Jumpin Jehoshaphat!! There were a lot of very bad things that could have happened that didn't.  Very lucky.

On a side note, whenever Lady Luck has shown me some favor, I never tempt her agin, so I have a hard and fast rule that once a machine has tried to terminate me, I terminate it.  After getting almost cut like that, the saw would have a new name, it would be called "On The Trailer and Gone."

Just saying it out loud......
Title: Re: Delta 18" Radial Arm Saw
Post by: 21incher on February 13, 2018, 05:26:38 PM
That is scary.  Was the blade guard in place?  :)
Title: Re: Delta 18" Radial Arm Saw
Post by: sawguy21 on February 13, 2018, 07:39:11 PM
That was my first question. My dad had an RAS for years, no mishaps but we were well aware of the damage it could cause if improperly used.
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on February 13, 2018, 09:58:18 PM
Thanks for the replies everyone.  I haven't decided what I'm going to do with this saw yet.  I'm no stranger to RASs, used several different kinds over the years.  The blade guard was not on when the blade came off, that was my fault.  I will fix the motor at least to get it up and running again.
Title: Re: Delta 18" Radial Arm Saw
Post by: Kbeitz on February 14, 2018, 03:29:51 AM
I think if it was my saw and I had the room that I would drill a hole at the end of the arbor and put a cotter pin.
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on February 14, 2018, 08:58:40 AM
Good idea K, I like it.  This saw is pristine, it's not wore out, just sat around for a while before I bought it.  I dont think I will get rid of it unless I can find a bigger 3 hp unit down the road.
Title: Re: Delta 18" Radial Arm Saw
Post by: Brian_Weekley on February 14, 2018, 01:17:06 PM
My radial arm saws are DeWalts--not Deltas so I'm not very familiar with your model.  However, the motor doesn't look right to me--is it original or was it replaced (that fancy aluminum around the capacitors doesn't look like something you'd find on a vintage RAS motor)?  Radial arm saws should have left-handed threads on the arbor.  If someone replaced the motor with one that has right-handed threads, that might explain why the nut spun off.  Does the arbor still freely turn?  What exactly was happening when the blade came off--was it right after startup, was the motor just sitting there running with the blade spinning, or was it under load?
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on February 15, 2018, 09:59:57 AM
Everything on this saw including the motor is stock, it's all original.  Don't know the year it was made, but probably in the 1990's or 2000's so it's not what I would call vintage. It's a relatively new RAS. Here's a picture of the cover for the capacitor housing.  I will have to double check the threads, but I am pretty sure that they are left-handed.


(https://forestryforum.com/gallery/albums/userpics/44509/20180212_165246.jpg?easyrotate_cache=1518705216)


The arbor still turns freely, like nothing happened.  Here is what happened:  I fired up the saw and made a few cuts without any issue.  The saw was running under no load while I was preparing for the next cut and I heard a different sound like a new vibration coming from the machine.  Before I could even shut it off to see what was going on, the nut backed out and the blade dropped off.  I powered down asap after recovering from the blade hitting me.  After changing my pants and thanking God, I started the motor up with no blade on it to see if I could figure out what happened.  It spun up and that's when the capacitor started smoking.  Of course I shut it down asap.  So I don't know if the capacitor failed before or after the accident.

Now to help understand, I have the saw set up a little out of the ordinary.  The blade is tilted roughly 58 degrees from vertical and it is quite a bit higher than the table.  Here is a picture of the motor tilted. 


(https://forestryforum.com/gallery/albums/userpics/44509/20180212_164025.jpg?easyrotate_cache=1518705193)


I bought this saw last year and used it a good bit set up just like this with no issues.  This was the first time I had used the saw for several months. 

With that angle, that's how the blade came off so fast, gravity was pulling it down with no nut to hold it in place.  The reason for the odd setup is that I use this saw to put points on wood stakes that I make.  I made a jig to hold the stakes and line them up 10 stakes at a time.  Cut a taper on one side of the row of stakes, flip them over and cut the other taper.  Here is a picture of the jig with stakes on it.  One side has already been cut, the stack flipped over and ready to cut the other taper off the bottom.


(https://forestryforum.com/gallery/albums/userpics/44509/20180215_095519.jpg?easyrotate_cache=1518706662)


Note in this picture the motor is NOT tilted like it would be when cutting the taper.  The taper is cut off the bottom of the stakes and then they are flipped over to cut the other taper. 

It works well and you can point a lot of stakes quickly as long as your blade stays on the machine!
Title: Re: Delta 18" Radial Arm Saw
Post by: Kbeitz on February 15, 2018, 01:00:18 PM
I can't tell from the pictures but if that motor has brushes and the capacitor shorted
to the run windings it could have worked as regenerative braking and that
would make a left hand nut come off.
Title: Re: Delta 18" Radial Arm Saw
Post by: jsmcauley on February 20, 2018, 01:16:56 PM
I don't know if your Delta uses a potential relay or a centrifugal switch, but I would thoroughly inspect the start circuit on that motor. Something caused the motor to stop suddenly and spin off the blade. Please let us know what you find.

Scott. 
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on February 20, 2018, 06:52:54 PM
I believe it has a relay to switch the start capacitor off, not a centrifugal switch but I am not an electrician or motor expert.  That being said, I am going to take the motor in to a shop and have a professional look at it and fix it up right.  I will update this post with what they find but I can't take it in until next week since I will be out of town the rest of this week.

Oh I did double check the arbor, it does have left hand threads.
Title: Re: Delta 18" Radial Arm Saw
Post by: Kbeitz on February 20, 2018, 07:41:22 PM
I do remember being able to buy a timed relay for motors when you could not buy replacement points for them anymore. I don't know if you can still buy them since current relays came out.
Title: Re: Delta 18" Radial Arm Saw
Post by: rjwoelk on August 18, 2018, 10:52:03 AM
Slowjoe how did you do with your saw? What was problem and did you get it fixed?
Title: Re: Delta 18" Radial Arm Saw
Post by: SlowJoeCrow on February 20, 2019, 10:46:23 AM
Well, about that...
I have been out of the shop for a while.  Taking the motor in to get it fixed is still on the to do list.  It's just sitting idle for now.