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General Category => General Scroll Saw Talk => Topic started by: Gabe on March 03, 2018, 11:33:50 pm

Title: DW788 knob Mod
Post by: Gabe on March 03, 2018, 11:33:50 pm

Thought I share the mod I did on the knob blade holder. It works great and is more comfortable then the original. BTW it cost alot cheaper to make
this mod than buying a replacement knob. Hope this helps a few of you out there.

I used epoxy to glue the bolt to the wood, the pictures should explain the build.

Gabe

Title: Re: DW788 knob Mod
Post by: jscott2 on March 05, 2018, 07:31:58 am

Gabe,

You have joined the ranks of those who have made a new knob to help clamping the blade.  With a larger handle, you can put more torque on the knob which could damage the clamp assembly.  This http://scrollsawworkshop.blogspot.ca/2015/07/technical-question.html?m=1 (http://scrollsawworkshop.blogspot.ca/2015/07/technical-question.html?m=1) has some good suggestions and a warning about possible damage from over-torquing the larger knob.

Your replacement bolt doesn't have the rotating tip that is on the original - see the first picture in the link.  If you prefer your new knob, you could replace the set screw on the left of the clamp with the knob from the right side.  This will reduce twisting of the blade as you clamp it in place. 

Hope this helps,
Jim

Title: Re: DW788 knob Mod
Post by: Jimm on March 19, 2018, 06:08:25 pm

I made the handkw that Steve has a pattern for and have been more than happy with it. Easy to make and made it from scraps I had in the shop.

Title: Re: DW788 knob Mod
Post by: Dwray1234 on April 13, 2018, 10:20:52 am

I have read several posts about the Delta\Dewalt thumb screws that have the rotating tip, which stays stationary as you tighten the blade. I currently have the 16" Porter Cable scroll saw,( I have not saved up to move up the ladder in saws yet), and I molded 2 new screws for locking the blade in, but the originals did not have the rotating tip. I am actually looking for a better blade clamp AND screws, but I will settle for any thumb screws that might be interchangeable with mine.

Any help?
Thanks

Title: Re: DW788 knob Mod
Post by: justlarry on April 13, 2018, 11:15:37 am

Quote from: Dwray1234 on April 13, 2018, 10:20:52 am

  I am actually looking for a better blade clamp AND screws, but I will settle for any thumb screws that might be interchangeable with mine.

Any help?
Thanks

Fellow scroller had the Porter Cable saw.  We tried the screws from my Delta 40-690 saw (the DW 788 clone) and they worked in the PC so he ordered a set for his saw. 

I use anti-sieze compound on the clamp screw threads.  For me, it takes less effort to tighten and loosen them and I do not have the mods taking up space for my thumb and finger.

Larry

Title: Re: DW788 knob Mod
Post by: Dwray1234 on April 13, 2018, 01:05:56 pm

I have been trying to find a link to order these. I will do to look up the Delta model replacement parts and see if I can find those thumb screws.

After checking on the Delta 788, it looks like those are the ones I need, now if I can find them for less than $12.63 each

Title: Re: DW788 knob Mod
Post by: Dwray1234 on April 13, 2018, 01:21:01 pm

I looked up the thumb screws for the Delta 40-694, but they do not show that they have the rotating tip, but look just like the original thumb screws for my PC. Does anyone have a link to these thumb screws ?

Thanks,

D.W.

Title: Re: DW788 knob Mod
Post by: justlarry on April 13, 2018, 03:30:09 pm

Quote from: justlarry on April 13, 2018, 11:15:37 am

We tried the screws from my Delta 40-694 saw (the DW 788 clone) and they worked in the PC so he ordered a set for his saw. 
Larry

I really messed my info to you.  I have the Delta 40-690  not the 694.  The 690 and 788 part numbers should be the same.

Title: Re: DW788 knob Mod
Post by: Dwray1234 on April 13, 2018, 04:36:24 pm

Larry, the thumb screws for the 788 are the ones with the rotating tip,( I found a site that has a much better closeup.) I could not find them much cheaper, so I spent 11 bucks a piece just to basically do a test run and see if my blade clamping improves. My wife says I am hard headed, and I am almost inclined to believe her.  :P

Title: Re: DW788 knob Mod
Post by: Dennis123 on April 17, 2018, 09:31:16 am

I've also found that a very light sanding with 220 grit garnet paper on the top of each blade just before mounting nearly eliminates blade slippage for me. :)

Title: Re: DW788 knob Mod
Post by: Norm Fengstad on April 17, 2018, 09:50:30 am

My  dewalt 788 type 1 clamps quite well, I do from time to time remove the knob to clean the pad is clean

Title: Re: DW788 knob Mod
Post by: Dwray1234 on April 24, 2018, 08:52:48 pm

Well, after many days of waiting, I finally got my order in of the Dewalt 788 replacement thumbscrews that have the rotating tip on them. They were not cheap, as I paid $11/each for them. They fit perfect in my Porter Cable, and after cutting with it for quite a while today, I had no slipped blades and no hockey sticks. Porter Cable should replace all of theirs with this style of thumbscrew.

Thanks for all the advice from everyone.   ;D ;D ;D ;D