Issues with my Excalibur

[Montserrat]

Maybe some of you can tell me what to check?  As of recently, the blade in my excalibur does not hold the tension.  I.e. I tighten it, it makes the appropriate pling sound, I start sawing and then it wobbles, so I loosen the plastic tension switch and now the blade make a bow/arch, even though the screws in top and bottom are still tight.  then I loosen and retighten the top screw and the game starts over again. 

 

I have retightened the counter screw/bolt or whatever it is called that opposes the tightening screw in the top - to no avail.  Today while cutting poplar 3/4" I broke three #7 blade and one #3. 

 

any ideas what needs to be adjusted on the saw? 

 

 

Love scrolling, but I am not a technician. 

Edited March 13, 2016 by Montserrat

[amazingkevin]

Maybe some of you can tell me what to check?  As of recently, the blade in my excalibur does not hold the tension.  I.e. I tighten it, it makes the appropriate pling sound, I start sawing and then it wobbles, so I loosen the plastic tension switch and now the blade make a bow/arch, even though the screws in top and bottom are still tight.  then I loosen and retighten the top screw and the game starts over again. 

 

I have retightened the counter screw/bolt or whatever it is called that opposes the tightening screw in the top - to no avail.  Today while cutting poplar 3/4" I broke three #7 blade and one #3. 

 

any ideas what needs to be adjusted on the saw? 

 

 

Love scrolling, but I am not a technician. 

sounds serious?

[Jim Finn]

I had a similar issue, years ago, with a DeWalt.  In my case ,while cutting 3/4" wood I was pushing too hard and streching the blade.  I learned to slow down my feed rate a lot.

Edited March 13, 2016 by Jim Finn

[WayneMahler]

Check your blades for oil fro the manufacturing process. Sometime the oils not cleaned off the blade. Ran into this and cleaned the bottom and top of the blades and problem was resolved. A little denatured alcohol or mineral sprits fixed the problem. Remember to clean the clamps too though.

[JimErn]

Maybe some of you can tell me what to check?  As of recently, the blade in my excalibur does not hold the tension.  I.e. I tighten it, it makes the appropriate pling sound, I start sawing and then it wobbles, so I loosen the plastic tension switch and now the blade make a bow/arch, even though the screws in top and bottom are still tight.  then I loosen and retighten the top screw and the game starts over again. 

 

I have retightened the counter screw/bolt or whatever it is called that opposes the tightening screw in the top - to no avail.  Today while cutting poplar 3/4" I broke three #7 blade and one #3. 

 

any ideas what needs to be adjusted on the saw? 

 

 

Love scrolling, but I am not a technician. 

I just got a used ex-21 and had the same problem, I found the cause on another site.

 

Insure the upper arm is parallel to the table top.  Use the back tension knob to adjust it

 

When you install the blade, install the top of the blade first and tighten the wing knob.

Insure the upper arm is all the way down, and the blade in in the slot in the bottom blade holder and tighten

Then flip the tension lever and use the back tension adjust if necessary.

 

Once the back tension knob is adjusted it should not  have to be adjusted again.

 

the bottom of the blade can extend below the blade holder, but it can NOT extend above the top one.

 

edited cause I have not had enough coffee yet, and again for the same reason, sigh

Edited March 13, 2016 by JimErn

[JimErn]

Now that I have had enough coffee I thought of one other thing I had to do.

 

You need a 3mm allen wrench and maybe blue locktite.  Blue, not red or green, red and green are semi-permanent and permanent respectively and require a lot of torque and sometimes a torch to break them loose.  Any auto parts store will have it, and maybe home depot.

 

on the left side of each blade holder, opposite the wing knob you tighten on the blade, is a set screw.  Get down below the table with a good penlight and check to see that the set screw does, does protrude slightly into the slot where the blade goes.  If it does not use the allen to adjust the set screw.  adjust both top and bottom the same

 

If the set screw turns really easily, back it out, put a drop or two of blue loctite on the threads and then turn it back in to where it should be and go have lunch to give it time to set up.

[ike]

you might try anti sieze on the blade tightening screws. A tube is about $5 and will last you 15 years.

[Montserrat]

so many wonderful tips - thanks guys - I will go to work on it!

[jerry1939]

In the past, I read about people having issues with blades slipping.  Whenever I put in a new blade, I sandpaper both sides of each end of the blade.  I don't have your problem, if that's what it is.

 

http://www.scrollsawvillage.com/topic/15942-my-new-command-control-center/?hl=command

 

jerry

 

[trackman]

Don't know how old your saw is but mine after 5 years of use the bearings that holds the bottom clamp wore out. This let the arm "jerk) the blade loose.

[Lucky2]

Monti, it seems as if you have a tension issue, there is a few things you can do to try to solve them. Remove the upper and lower clamp screws, and check out the little pivot pins that are in the end of them. Make sure the pins can move, and sand the end of the pins to scuff them up. Doing this should make the clamps hold on to the blade better, so it can't slip in the clamp. Another thing that should help solve your issue, is to apply pressure to the upper arm when installing the blade. What I do when I install a blade, I always attach the lower end of the blade in the clamp first. I make sure that there is enough blade under the clamp screw, then for the top clamp, I always apply downward pressure to the upper arm while tightening the clamp screw. Not a lot of pressure is needed, but, if done right you'll never have to adjust the tension screw again. I've had my EX21 for 5-6 years now, and I only ever needed to touch the back tension knob for spiral blades.

Len

[Montserrat]

Thanks!  I will try that, too!

[RangerJay]

I top feed my blades and on my EX 16 I was starting to have trouble with blades popping out of the lower clamp and developing a sharp bend at the end of the blade - took me a little while to figure out the problem was me - over time I had developed the habit of purshing the lower part of the blade too far into the clamping frame - meaning I was levering the bottom of the blade away from the actual clamp to the point where the blade was not square and only partially held.  The result was that the blade would pop out under pressure - or slip. Once I started looking at what I was doing it was easy to see the issue and correct how I was positioning the blade for clamping.

[Doug]

It sounds like blade slippage under tension.  Do what Len said but take out the set screw also to clean the surface of the set screw.  When reinserting the set screw use the blue loc tite and get the surface of the set screw flush with the inside surface of the clamp - do this upper and lower.  I cannot speak to all blades but I know FD blades come with a little film on them which ultimately can cause this slippage under tension so for all blades, not just FD, I dip the ends in denatured alcohol whenever I open a dozen, wipe the ends, and then before using the blade scuff the ends with 220 grit sandpaper.

[Montserrat]

That is interesting! Upon reflection I realized that I did not have the problem when using Olson Mach blades, but it started, when I switched to Pegas Modified Geometry.  Maybe the ends are treated differently the different manufacturers. 

[kywoodmaster]

Olsen blades are not oil treated. Have never had a slipping problem with them.

[Roberta Moreton]

This is an old post. I do understand.  But. My knob in the back keeps moving. I put lock tight on the set screw. I have the Pegas clamps. I bought and installed the replacement parts for the clamps. The back knob moves.  I had to go back to the 788 to get my order done. Suggestions please?!

[kmmcrafts]

52 minutes ago, Roberta Moreton said:

This is an old post. I do understand.  But. My knob in the back keeps moving. I put lock tight on the set screw. I have the Pegas clamps. I bought and installed the replacement parts for the clamps. The back knob moves.  I had to go back to the 788 to get my order done. Suggestions please?!

Same issue I had with my Excalibur 21" saw.. I talked to Ray and he had me go through a couple test things.. which basically ruled out that the knob itself wasn't loose or moving.. which in my case it wasn't the knob.. turned out to be loose tolerances on the rod threads and or square nut that it screws into or maybe both.. He suggested to me that it needs a new rod and nut to fix the problem.. However I took it apart and put blue thread locker on the threads.. not an issue with it since and that was like 1.5 years ago and around 200 hours run time on my hour meter.. 

I'm not sure where the topic is now but many other quick and easy temporary fix suggestions.. one was something to do with wrapping a rubber band around it.. another was using some electrical tape under the knob to prevent it from being able to turn on it's own.. I'll do a quick search to see if i can find the topic..

 

Here is the topic I posted when I was having this issue.. Might find something to help you without having to disassemble the saw.. 

https://www.scrollsawvillage.com/forums/topic/33000-excalibur-adjusting-itself-observation/?tab=comments#comment-368976

Edited June 17, 2020 by kmmcrafts

[NC Scroller]

16 hours ago, Roberta Moreton said:

This is an old post. I do understand.  But. My knob in the back keeps moving. I put lock tight on the set screw. I have the Pegas clamps. I bought and installed the replacement parts for the clamps. The back knob moves.  I had to go back to the 788 to get my order done. Suggestions please?!

Berta I texted you something to try.

[NC Scroller]

For anyone else here is what I did to resolve the issue.  This rubber band has been in place for well over a year and the knob has not moved a bit. 

Simple-Easy- No Cost fix = Priceless

 

 

[OCtoolguy]

7 hours ago, NC Scroller said:

For anyone else here is what I did to resolve the issue.  This rubber band has been in place for well over a year and the knob has not moved a bit. 

Simple-Easy- No Cost fix = Priceless

 

 

I adapted your fix back when you posted it.

[Roberta Moreton]

On 6/17/2020 at 12:17 PM, NC Scroller said:

For anyone else here is what I did to resolve the issue.  This rubber band has been in place for well over a year and the knob has not moved a bit. 

Simple-Easy- No Cost fix = Priceless

 

 

And...it’s fixed and wonderful!  

[OCtoolguy]

On 3/13/2016 at 7:58 AM, Montserrat said:

so many wonderful tips - thanks guys - I will go to work on it!

Hey Montserrat, where are you located in Tennessee? We are getting ready to relocate to your fine state in or around the Knoxville area. Maybe we'll be neighbors.

 

[heppnerguy]

 you can sand the inserts of the set screws,,,,,,tighten the thumb screw as much as you can.....but the truth of the matter is, this indicates it is time to replace the inserts of the set screws and thumb screws. Sanding the tips can help sometimes and even the blade ends but changing the inserts makes your saw like new again. The biggest problem with the above efforts is by having to apply more pressure to the thumb screw will eventually cause  one or two  problems or both. You will eventually wear out the threads on the set screw and have to replace it or you will cause the blade clamp to stretch and then the tips are no longer parallel and hence the little insert is only able to connect it's holding  surface in part and the blade slips.     Steve Good suggests that the inserts be replaced about 2 to 3 times a year depending on how often you use your saw. By making this change on a regular basis the clamp with not get stretched out of alignment, and the threads will not get warn and wobbly. Try it, I think  you will be pleasantly surprised if you do.

Dick

heppnerguy 

[Fedido]

On 6/24/2020 at 12:18 AM, heppnerguy said:

 you can sand the inserts of the set screws,,,,,,tighten the thumb screw as much as you can.....but the truth of the matter is, this indicates it is time to replace the inserts of the set screws and thumb screws. Sanding the tips can help sometimes and even the blade ends but changing the inserts makes your saw like new again. The biggest problem with the above efforts is by having to apply more pressure to the thumb screw will eventually cause  one or two  problems or both. You will eventually wear out the threads on the set screw and have to replace it or you will cause the blade clamp to stretch and then the tips are no longer parallel and hence the little insert is only able to connect it's holding  surface in part and the blade slips.     Steve Good suggests that the inserts be replaced about 2 to 3 times a year depending on how often you use your saw. By making this change on a regular basis the clamp with not get stretched out of alignment, and the threads will not get warn and wobbly. Try it, I think  you will be pleasantly surprised if you do.

Dick

heppnerguy 

I had the same problem and after sanding the tips four and five times, I said to myself "Self, time to change these". Haven't had a problem since. used to frustrate me as the blade would slip while in operation. another blade down the tubes.