Blade Retention Knob

[Aaron K5ATG]

I don't know what else to call it so I'm going with balde retention knob. Here is my problem. I have a Craftsman scroll saw that I got in 2006. It has been a great saw and tit still works pretty good. My biggest problem with it is the blade rention knob. Its small round and hard to grip. I tried to epoxy a wooden knob to it but it didn't work. I have a nasty contraction and tendonitis in my right hand. Normally it's not a huge problem because I'm left handed. In the last couple of weeks it has been very painful at tighting and loosening this knob. Painfull to the point that it makes me not want to use the saw. Here is what I have found out about this cursed knob of pure evil. 

• The entire length (including the knob is 20mm
• The diameter of the knob is 16mm
• The diameter if the bolt is 3.8mm
• The length of the bolt is 13.5mm

I took it to my local hardware store and the guy told me that it's 8-32-4mm, so I thought great! I can get online find a replacement with a more comfortable knob and be happy. I'm not much of a hardware guy and the information that the hardware guy gave me.  8-32-4mm is a bit confusing. I have not been able to find me a better knob. I would really be grateful if someone could point me in the right direction or tell me exactly what I need to be look for.

Thank you

 

[preprius]

i recently broke my blade retention knob.

i did the epoxy wood  (purpleheart scrap) fix and it worked.  what i learned is 2 procedure. 

1.  check out super glue CA and baking soda videos. 

2 use structural epoxy , i found t88 from "system3".

 

[Wichman]

If you go to Steve Good's website here he has a wealth of information on this subject.  

[Aaron K5ATG]

Well I wasn't able to resolve the problem but I got a suprise early Christmas present. 

I got the 22" Bauer scroll saw from Harbor Freight. Since the Craftsman still works, it can be a great backup saw. Now I can still work on fixing the knob problem on the Craftsman but I won't be so pressed for time on it. 

Thank you for all of your suggestions and help. 

[daveww1]

enjoy your new saw

[Scrappile]

Here is a good place to look.  https://www.mcmaster.com/products/screws/thumb-screws-2~/stainless-steel-low-profile-knurled-head-thumb-screws-9/

You will really enjoy the new saw.  

Edited December 8, 2025 by Scrappile

[JTTHECLOCKMAN]

Very good. The one draw back is the knob is still a small knob that maybe a problem. Good luck.

[Denny Knappen]

Enjoy the new saw.  I have a customer that put the Pegas Chuck Head Set on the Bauer with no problems.

[OCtoolguy]

Congrats on your new toy. I was going to suggest making your own knob but now it doesn't seem to be as pressing as it was. I would cut out a round piece of hard wood and bore a hole the same diameter as your existing knob but minus a few thousanths. Use a Forstner bit to bore the hole so it has a flat bottom. Then, mix up some epoxy and place the knob in the hole and tap it down into the recess with a good glob of epoxy in the hole beforehand. Make sure the knob is in straight. Let it set overnight. Once you have it in hand, take a rat tailed file and file some grip areas around the outside. It should be great from then on. You do have to be a bit careful about adding weight to the knob because of vibration so stay away from anything heavy. I made a couple of knobs out of 5/16" plywood for my Dewalt and it worked great.  Best of luck. 

[Aaron K5ATG]

5 hours ago, Denny Knappen said:

Enjoy the new saw.  I have a customer that put the Pegas Chuck Head Set on the Bauer with no problems.

Thanks for the Pegas idea, I will look into it.

[philipcollier]

I used another scroll saw to cut the round knob into a wing nut shape on my Craftsman 16".  I also replaced the main tension knob on the back with a flip down lever from a very old 16" Delta, since it didnt have a tensioner near the head.   My poor Craftsman has been rebuilt and adapted many times over the past 21 years, but I just got the 22" Bauer just over a month ago myself.  Keeping the Craftsman Franken-Saw though.  It has kept me scrolling for many years (originally from a pawnshop for $15.00.)

[kmmcrafts]

If I had this issue I don't think I would "glue" a bigger knob onto the thumb screw but rather make a tool to use for the knob. Rather than use the bigger round screws I would use the style that has wing grips.. Hope I'm making sense with the terminology , LOL. A larger knob glued on is added weight and maybe vibration to the saw having that extra weight out on the end of the arms may also be more wear on the saw. You could just make a larger handle / tool that would slip over the wing style knob to make it much easier and being a tool you slide over it you could make it as big as you need. 

Another option is to just replace the screw with a square head screw or any head type and use a wrench. I was thinking a square head bolt because then maybe ( if the correct size head ) you could use a clock winding wrench like Hegners use. Just remember whatever you decide to try and do to help.. anything larger is going to be putting more torque on that small screw.. don't over tighten and ruin your blade chucks.   

[Wichman]

Couple of things 

1. There are two basic ways to grip the knob; the pinch ( photo 1 ) and the wrap ( photo 2 ). Photo 3&4 show the large wooden egg I found at Hobby Lobby, it is very comfortable in my hand. You could use one to make a handle for a T bolt. 

 

 

 

 

[Aaron K5ATG]

Thar egg looks like it would be very helpful for those of us that have arthritus and other hand issues. I hace contraction and tendonitusdeveloping in my right hand that can be bothersome but it isn't a deal breaker for me because I'm left handed. 

I made a wooden knob and used Gorllia epoxy and that didn't work at all. I was really supprised that the epoxy failed the first time I touched the knob after I used it. I was going to keep experimenting but I got the new scroll saw and I don't have the room in my shop to keep the old saw around just to play around with the knob. 

I think that I found out a reason why my blades were bending. I wasn't clamping the blade on the end. I would have the the top of the blade extend about 1/8" above the set screw and the thumb screw. I noticed that this morning. I guess that it was a habit that I did without realizing it. I thing that I started doing that on the old saw because it didn't have the clamping force that the new on has. So I started attaching the blade at the end of the blade and it seems to be working.