Got a great deal on a Dremel rotary saw with flex shaft at an estate sale.  Flex shaft Model 961 requires an insert that did not come with the saw.  Per Dremel, this model was discontinued in 2004.  Does anyone have this saw and shaft?  if so, can you post a pic of the insert along with rough dimensions?  

This help?

 

https://images-na.ssl-images-amazon.com/images/I/71K4FyJFmmL.pdf

Thanks Lew, it beats the instructions I have found.  Now If I can find parts on EBay or Amazon.

Can you snap a close-up photo of the insert in the shaft and post it here? If you can’t, a quick set of rough dims would help: outside diameter, insert length, and the internal bore shape/diameter (is it round, keyed, splined?). I can take a look and suggest compatible parts or adapters or where to hunt for a replacement.

Can you snap a close-up photo of the insert in the shaft and post it here? If you can’t, a quick set of rough dims would help: outside diameter, insert length, and the internal bore shape/diameter (is it round, keyed, splined?). I can take a look and suggest compatible parts or adapters or where to hunt for a replacement.

Edited December 3, 2025Dec 3 by ASteinfield

ASteinfield:  All I have is the Dremel schematic info provided by Lew.  See pick and info below.  Have called Dremel, Saw was discontinued in 2004, these parts have been discontinued according to Dremel and several Parts Warehouses.  I was hoping that someone on this sight had a similar tool and could post pics so I can try and build one.  Note: drawing does not show the hex shaft that goes thru 6 & 7.     Thanks for the help.

 

Six is listed as Part No. 2610915666 Driver Cap   Normal cap is another part no and called collet nut, which I have. 

Seven as 2610915667 Plug

https://www.mmtoolparts.com/bosch-drive-cap-2610915666

 

https://shop.intmfg.com/products/bosch-2610915666?srsltid=AfmBOoq-pg4TQ3HvOuK_vXRwElmXlx2MZrIyWSjN_GfcW_RQinpLp3NY

 

Found this 

Here’s a picture of the 667 part 

Thanks Lew.  I found a driver cap, not same model so I am not sure about the threads but less than $10 so I will give it a shot.  Any chance the pic rotates so you can see inside?

10 minutes ago, Lost Oki said:

Any chance the pic rotates so you can see inside?

Sorry no. Maybe I can find another 

On 12/4/2025 at 8:03 PM, Lost Oki said:

Thanks Lew.  I found a driver cap, not same model so I am not sure about the threads but less than $10 so I will give it a shot.  Any chance the pic rotates so you can see inside?

Driver cap arrived, not the right size, too small.  I did find the plug, one step closer. 

Note:  following pics are of the driver cap plus square hole that would need to be on the end.

Specs.   Pic 1  Square hole is 2.92 mm wide, flat side to flat side

              Pic 2  overall height is 19.68 mm

              Pic 3 inside dia is 11.56 mm  outside dia is 16.46 mm

              Threads, fine, guessing metric, I don't have anything that fits.

Thanks for all the help.

 

 

Edited December 14, 2025Dec 14 by Lost Oki

Any chance one of these might work?

 

https://www.ebay.com/itm/351192028019

 

https://www.eszterf.com/product-p-609286.html

 

https://cwatson.co.uk/drive-nut-for-dremel-flexi-shaft-rotary-tool-attachment

40 minutes ago, lew said:

Any chance one of these might work?

 

https://www.ebay.com/itm/351192028019

 

https://www.eszterf.com/product-p-609286.html

 

https://cwatson.co.uk/drive-nut-for-dremel-flexi-shaft-rotary-tool-attachment

Thanks Lew, but no, all fit a hand held dremel.  I got pulled away before I finished post adding specifics to above post which I will do.

These two keep showing up-

https://www.mmtoolparts.com/bosch-drive-cap-2610915666#additional

 

https://2mequipment.com/products/bosch-power-tool-2610915666-drive-cap

 

 

Looks like PartsWarehouse has one, special order, no picture or specs.  Anyone familiar with this site

Thanks Lew, decided to use M&M Tool, part on order, hope its the right one.  Same part no, said it fits a dremel, just no model no.  and no picture.  Here's hoping.

 

3 hours ago, Lost Oki said:

Looks like PartsWarehouse has one, special order, no picture or specs.  Anyone familiar with this site

Yes, I've used them before. IIRC for dryer parts and I think Weedeater parts. Usually a little higher priced, but they had OEM items in stock.

If all else fails, maybe this-

 

https://www.ebay.com/itm/195791244222?_trkparms=amclksrc%3DITM%26aid%3D1110013%26algo%3DHOMESPLICE.SIMRXI%26ao%3D1%26asc%3D297286%2C296753%26meid%3D8bb66fe56bf54fefaedb921f82d26e17%26pid%3D101196%26rk%3D2%26rkt%3D12%26sd%3D267250651085%26itm%3D195791244222%26pmt%3D1%26noa%3D0%26pg%3D2332490%26algv%3DSimRXIVIWithAspectRecallAndDiversity%26brand%3DUnbranded&_trksid=p2332490.c101196.m2219&itmprp=cksum%3A1957912442228bb66fe56bf54fefaedb921f82d26e17|enc%3AAQAKAAABEOqMkuSAG6ItrRvsdD9sfIOitRvq9S3zkbLwWuQv0VbI6jNBMxuv2D6ql7XdjmAaGvYigZue6picfYW6H6ASTMoDQcK8fhXvYsCbqNFH%2B4QJKCtaw0JpFMi%2FsJbCV0RvBEDjl1E%2F817DbSQMaGkcS2wkNIaLadQExaKRhTMySHpltfRhI04p8ljc7AqYqwAGDqtf9V5785tBCFX09yCu9IW8RIm9XapkGC9Kc6MrSjNMhqa9OemaZvpMq4Dc6MuIDrFBBJFQ2uIx7pUp%2BDZGoNwdsBHIwY0%2BI48z6ZG9069pjFtKNqKUvwNz60XNZ9D5MDzhmD8QeCwu2vqMDzpqe3M50koILVKIWWlzFR%2Beos3d|ampid%3APL_CLK|clp%3A2332490&itmmeta=01KCMNBA3HADVSCFJATG4XT5FY

Followup on the part for my search for the dremel flex shaft part.  Ordered two from M&M Tool, out of stock but part on order, arrived last week and it fits!!

With the warm weather (low 70"s)I have been upgrading my garden raised beds and have not put it to the test but feel confident it will work.  THANK YOU for all the help, would not have found it without your direction.  Cold weather setting in this week I will get to it along with cleaning the shop.  Note:  Neighbor had an old craftsman planer/joiner he wanted to give away.  Blades in good shape and sharp, motor works, came with base and wheels, now to find a place for it in my small shop.  Free is always good.

32 minutes ago, Lost Oki said:

Followup on the part for my search for the dremel flex shaft part.  Ordered two from M&M Tool, out of stock but part on order, arrived last week and it fits!!

With the warm weather (low 70"s)I have been upgrading my garden raised beds and have not put it to the test but feel confident it will work.  THANK YOU for all the help, would not have found it without your direction.  Cold weather setting in this week I will get to it along with cleaning the shop.  Note:  Neighbor had an old craftsman planer/joiner he wanted to give away.  Blades in good shape and sharp, motor works, came with base and wheels, now to find a place for it in my small shop.  Free is always good.

Awesome!!!!