Excalibur blade hold down T-bolts T-bolts

[Eplfan2011]

Was watching a Steve Goode video about changing out the inserts in the Excalibur blade hold down T-bolts

Anyone tell me the size of those Excalibur  T-bolts, are they 1/4 20?

[kmmcrafts]

1 hour ago, Eplfan2011 said:

Was watching a Steve Goode video about changing out the inserts in the Excalibur blade hold down T-bolts

Anyone tell me the size of those Excalibur  T-bolts, are they 1/4 20?

Nope, LOL.. I have a Excalibur and three Hawk scroll saws and the Hawks are SAE and the Excalibur is metric... Been there tried that.. that being said though.. if they are dressed good on the Hawk.. I find you don't have to clamp them down with much force and less force helps them last much longer. If you get bent ends of the blade.. you have a few issues to look at.. first being is the end of the bolt completely flat, second is the set screw on the opposite side screwed in far enough.. and the third thing is.. are you clamping with too much force.

I bought some new thumb screws from Hawk ( Bushton MFG) and you'd think they'd dress the ends flat.. I specifically bought from them thinking they'd be dressed flat.. Instead they sold me the same thing I'd get at a local hardware store at 1/3 the price, LOL.. 

I made my own tool just out of a piece of wood scrap to dress the screws on my power sander.. Just drill a hole the size so the screws will thread into the wood.. make sure you start them in straight.. screw them in until they just barely protrude the back side.. then have at it with the power sander or belt sander.. even just laying a piece of paper on the bench and hand sand it.. they'll get a nice flat smooth clamping edge.. Use some blue loc-tite thread locker on the set screw so it stays put.

I like to use a feeler gauge to set set screw into the blade chucks.. this way both top and bottom set screws position the blade in the exact same position.. I pick whatever feeler gauge and place it in the slot where the blade goes and turn the set screw in until it slightly touches the feeler gauge.. might take some practice to get the right size feeler gauge so you can have enough space for the blade and get the thumb screw to go in as well. Hope that make some sense. 

[Eplfan2011]

6 minutes ago, kmmcrafts said:

Nope, LOL.. I have a Excalibur and three Hawk scroll saws and the Hawks are SAE and the Excalibur is metric... Been there tried that.. that being said though.. if they are dressed good on the Hawk.. I find you don't have to clamp them down with much force and less force helps them last much longer. If you get bent ends of the blade.. you have a few issues to look at.. first being is the end of the bolt completely flat, second is the set screw on the opposite side screwed in far enough.. and the third thing is.. are you clamping with too much force.

I bought some new thumb screws from Hawk ( Bushton MFG) and you'd think they'd dress the ends flat.. I specifically bought from them thinking they'd be dressed flat.. Instead they sold me the same thing I'd get at a local hardware store at 1/3 the price, LOL.. 

I made my own tool just out of a piece of wood scrap to dress the screws on my power sander.. Just drill a hole the size so the screws will thread into the wood.. make sure you start them in straight.. screw them in until they just barely protrude the back side.. then have at it with the power sander or belt sander.. even just laying a piece of paper on the bench and hand sand it.. they'll get a nice flat smooth clamping edge.. Use some blue loc-tite thread locker on the set screw so it stays put.

I like to use a feeler gauge to set set screw into the blade chucks.. this way both top and bottom set screws position the blade in the exact same position.. I pick whatever feeler gauge and place it in the slot where the blade goes and turn the set screw in until it slightly touches the feeler gauge.. might take some practice to get the right size feeler gauge so you can have enough space for the blade and get the thumb screw to go in as well. Hope that make some sense. 

Thanks for the info, I've got 4 new ones ariving today, nice to know they will need flaterning. I still might give my FIL my upper and lower bladeholders and get him to machine me a new set and drill and tap them to the correct metric size so I could use the Excalibur ones.

Which still begs the question what size are the Excalibur ones?

 

[OCtoolguy]

1 hour ago, Eplfan2011 said:

Thanks for the info, I've got 4 new ones ariving today, nice to know they will need flaterning. I still might give my FIL my upper and lower bladeholders and get him to machine me a new set and drill and tap them to the correct metric size so I could use the Excalibur ones.

Which still begs the question what size are the Excalibur ones?

 

Not sure if this helps but according to the EX parts list the "set screw" is M6x8 so I'd say it's 6 mm x ?

 

[kmmcrafts]

There was a person on here some time ago that drilled the ends of the Hawk thumb screws to accept the Excalibur inserts.. so there is that option as well.. those tips rotate on the Excaliburs because they have a fixed blade chuck head.. Hawk chucks can swivel back and forth so they're not necessarily needed..

[Eplfan2011]

1 minute ago, kmmcrafts said:

There was a person on here some time ago that drilled the ends of the Hawk thumb screws to accept the Excalibur inserts.. so there is that option as well.. those tips rotate on the Excaliburs because they have a fixed blade chuck head.. Hawk chucks can swivel back and forth so they're not necessarily needed..

To be honest I think I'm over tightening I haven't had time to mess around down in the dungeon since I did this( been cutting up a old fiberglass tub for disposal.)

 After the football (or soccer to you guys) tomorrow morning I'm going to dress the new bolts that came today and go easier on tightening and give it another go

[OCtoolguy]

1 hour ago, Eplfan2011 said:

To be honest I think I'm over tightening I haven't had time to mess around down in the dungeon since I did this( been cutting up a old fiberglass tub for disposal.)

 After the football (or soccer to you guys) tomorrow morning I'm going to dress the new bolts that came today and go easier on tightening and give it another go

Also, if you clean the ends of your blades with mineral spirits to remove any oil and rub them with 220 sandpaper just enough to rough them up, you won't need to tighten so hard. I think it might have been @heppnerguy who put me onto that idea and it has worked well. Whenever I open a new dozen pack of blades I take a few minutes and do this.

[kmmcrafts]

I have blade storage tubes that I keep at the saw and only put a dozen or two in the tube at a time then keep the rest of them in the package they came in. Before putting them in the tube or unwrapping the wire from them I spray both ends with a quick shot of brake parts cleaner.. that removes to oil from the blades.. just be sure to use them in a timely manor or you may end up with them rusting, partly why I only keep a few in the storage tubes at a time and why i leave the others in the packages. I rarely "sand" the blades but have done it.. seems like the brake parts cleaner does the trick quite well for me so I don't have to take time to sand the ends.. I happen to work on cars enough that I have a case or two of brake parts cleaner spray cans around.. If you don't normally have it around the shop then rough up the ends as Ray mentioned..

[preprius]

@OCtoolguy quote   "rub them with 220 sandpaper"

I use a magnet (scrap with magnets) to hold a sandpaper to my rbi frame.  I scratch the blade up a bit before clamping.  

 

[Eplfan2011]

Just to clarify, what's happening is the blades a bending where the screw contacts them, as I said earlier I'm probably over tightening. 

 I've purchased some new knobs because the ones that were on it are cracked and ready to break. 

 

[OCtoolguy]

46 minutes ago, Eplfan2011 said:

Just to clarify, what's happening is the blades a bending where the screw contacts them, as I said earlier I'm probably over tightening. 

 I've purchased some new knobs because the ones that were on it are cracked and ready to break. 

 

Common problem. It's called hockey sticks. The first thing you need to do is make sure the anvil side (set screw) is protruding into the blade slot about 1 thread. Do this top and bottom. Using some blue Lok-Tite to keep it there. Once you have a blade locked in place check that the blade is in alignment top to bottom. Once that's done check that it is square to the table.

[Eplfan2011]

30 minutes ago, OCtoolguy said:

Common problem. It's called hockey sticks. The first thing you need to do is make sure the anvil side (set screw) is protruding into the blade slot about 1 thread. Do this top and bottom. Using some blue Lok-Tite to keep it there. Once you have a blade locked in place check that the blade is in alignment top to bottom. Once that's done check that it is square to the table.

Thanks Ray, I did this after reading an earlier post in this thread, they pretty much went back where they were.

The saw was cutting well beforehand just the hockey sticks.  When I replaced the blade I didn't wind down on it like I was doing before and all seems good and the blade stayed put. 

All in all I'm going to chalk it down to inexperience and my zealous application of force on the knobs, snuging it down then giving it a little extra seemed to work fine and no hockey sticks

[Ray109]

On 8/13/2022 at 3:33 AM, Eplfan2011 said:

Thanks Ray, I did this after reading an earlier post in this thread, they pretty much went back where they were.

The saw was cutting well beforehand just the hockey sticks.  When I replaced the blade I didn't wind down on it like I was doing before and all seems good and the blade stayed put. 

All in all I'm going to chalk it down to inexperience and my zealous application of force on the knobs, snuging it down then giving it a little extra seemed to work fine and no hockey sticks

I have Pegas blade clamps on my saw and I was having a bad episode of 'Hockey sticks"

On close examination I saw that the slot between the screw clamp and the anvil bolt was not allowing the blade to be clamped centrally. I cut and filed the slot deeper so that the blade was clamped  in the centre and I have never had a hockey stick since.

[DME72]

i was the one who made the clamps several years ago. they work well. i made my own inserts from 0-1 drill rod that i turned on my metal lathe. i wish Bushton manufacturing would make these for the saws they sell. i made a set for a member on here, but he no longer has the hawk scroll saw. the clamps worked really well at holding small blades. if i have time in the next day or so i will see about posting a picture of the clamps i made.