POTD- PROJECT OF THE DAY: What Did You Make In Your Shop Today?

[finsruskw]

Looking good.

I'd like to see how you formed the hangers. Is that 1/4" x 3" HR?

 

[extropic]

@finsruskw

That setup does a good job. Thanks for the pic.

 

[Shootymacshootface]

My son messaged me today. He is an excellent machinist and cnc programmer. I would ask for a picture, and I know he would send one if I asked, but I don't want him to get in any trouble. His company makes gubment stuff. I'm sure it's a part for Electric Boat in CT.
Here is our conversation.

 

[brino]

@finsruskw

Thanks for the picture of that press fixture.
It looks sturdy, stable and simple and obviously works great.
I could never have pictured or designed that!

Brian

 

[GoceKU]

New day new set of brakes to replace, this time on the little niva. The front calipers are original 40 year old and passenger side was dragging and wore down the brake pads. This summer i bought new calipers and pads and only now i found the time to install them. The Niva calipers are very unusual they have 3 piston and two circuits, also they are two piece design, aluminium piston part and cast brake pad bracket. Bleeding the air out of them was a nightmare but after 1,5 liter of brake fluid i have a firm pedal. Seeing the made in russia made me think about the war that is happening now in Ukraine.

 

[BGHansen]

POTD was making another arbor for a drill chuck for the Bridgeport. Over the years I’ve picked up a number of ½” capacity chucks with R8 (and other) arbors. My BP typically has an ER32 collet chuck mounted instead of R8 tooling as I find it more convenient to change collets at the spindle than reaching up for the draw bar. One of these would be a donor for a ¾” straight arbor.


So how many R8 arbors with 1/2" capacity chucks do you need? The one on the left would be getting a new arbor



Most of my projects involve using 3/8”, ½” or ¾” collets. It’s convenient to have drill chucks with those sized straight shanks for quick changes between end mills and drill chucks without having to change the ER32 collet size. I recently made up a couple of 3/8” arbors for some small Jacobs chucks, and had 0-1/4” and 0-1/2” chucks with ½” shanks already. Time for a ¾” one to complete the set.

The donor happened to be a Jacobs ball bearing chuck. First step was removing the chuck from the arbor which created a side project. My chuck wedges weren’t thick enough to bear between the arbor and chuck. So, off to the BP to make a spacer.


My wedges weren't thick enough to force the drill chuck off the arbor. . .


Milled a piece of 1/4" aluminum for a spacer


Couple of taps with a brass hammer and off came the chuck




Next step was matching the R8 arbor Jacobs’ taper with the compound. The arbor was chucked up and swept with a dial indicator. I rotated the lathe chuck out of curiosity and repeated; no change in the taper.


Chucked up the R8 arbor and swept the taper with a dial indicator. Tapped the compound with a brass hammer to dial in in.



Material of choice was 1” drill rod. Faced, center drilled and turned the end to the large diameter of the Jacobs taper. Then cut the taper with the compound. I don’t know its purpose, but the existing arbor had a relief groove which was cut also (stress riser relief?).


Turned the tapered end to the large diameter of the Jacobs taper (~0.825")


Taper cut with the compound


After a little polishing with a smooth file and 400-grit emery cloth


Test fit


Cutting the stress relief (?) groove



Next was turning the shank to diameter. I left a portion of 1” diameter stock at the base of the Jacobs taper for a bearing surface for the wedges in case the chuck needed to be removed from the arbor. Parted off with the band saw and faced/chamfered the end on the lathe.


Turning the shank to 3/4"


After a little polishing


Cutting off on the band saw


Faced and chamfered the 3/4" end



Then heat treated the arbor with a Thermolyne muffle furnace. After quenching, tempered to a dark orange (twist drill temper).


The Thermolyne takes about 30 minutes to get to 1550 F. Let it set for 10 minutes, then quench in motor oil.


Back into the furnace after quenching; tempered to a dark orange (~480 F)



Didn’t show it, but polished it up with a ScotchBrite wheel. Tapped it home with a brass hammer and there it is!


New arbor in the foreground


After a couple of taps with a brass hammer. In retrospect, I could have cut the taper a little smaller for deeper engagement.





Thanks for looking, Bruce

 

[mmcmdl]

So how many R8 arbors with 1/2" capacity chucks do you need?

32 , and not 1 less .

 

[dkemppai]

...Then cut the taper with the compound. I don’t know its purpose, but the existing arbor had a relief groove which was cut also (stress riser relief?).

I always thought that relief (and others similar) was done for grinding purposes. As the wheels wear when grinding, that relief should give the wheel a place to move past the end of the taper so that the last bit of taper can be ground with 'fresh' wheel a little further into the wheel. (If that makes sense).

But, then again, I could be way off on that...

 

[extropic]

I always thought that relief (and others similar) was done for grinding purposes. As the wheels wear when grinding, that relief should give the wheel a place to move past the end of the taper so that the last bit of taper can be ground with 'fresh' wheel a little further into the wheel. (If that makes sense).

But, then again, I could be way off on that...

Grind relief - so the wheel can finish the feature without bumping the shoulder and/or without leaving a corner radius.

 

[wachuko]

POTD was making another arbor for a drill chuck for the Bridgeport. Over the years I’ve picked up a number of ½” capacity chucks with R8 (and other) arbors. My BP typically has an ER32 collet chuck mounted instead of R8 tooling as I find it more convenient to change collets at the spindle than reaching up for the draw bar. One of these would be a donor for a ¾” straight arbor.


So how many R8 arbors with 1/2" capacity chucks do you need? The one on the left would be getting a new arbor
View attachment 401450


Most of my projects involve using 3/8”, ½” or ¾” collets. It’s convenient to have drill chucks with those sized straight shanks for quick changes between end mills and drill chucks without having to change the ER32 collet size. I recently made up a couple of 3/8” arbors for some small Jacobs chucks, and had 0-1/4” and 0-1/2” chucks with ½” shanks already. Time for a ¾” one to complete the set.

The donor happened to be a Jacobs ball bearing chuck. First step was removing the chuck from the arbor which created a side project. My chuck wedges weren’t thick enough to bear between the arbor and chuck. So, off to the BP to make a spacer.


My wedges weren't thick enough to force the drill chuck off the arbor. . .
View attachment 401452

Milled a piece of 1/4" aluminum for a spacer
View attachment 401451

Couple of taps with a brass hammer and off came the chuck
View attachment 401453



Next step was matching the R8 arbor Jacobs’ taper with the compound. The arbor was chucked up and swept with a dial indicator. I rotated the lathe chuck out of curiosity and repeated; no change in the taper.


Chucked up the R8 arbor and swept the taper with a dial indicator. Tapped the compound with a brass hammer to dial in in.
View attachment 401454


Material of choice was 1” drill rod. Faced, center drilled and turned the end to the large diameter of the Jacobs taper. Then cut the taper with the compound. I don’t know its purpose, but the existing arbor had a relief groove which was cut also (stress riser relief?).


Turned the tapered end to the large diameter of the Jacobs taper (~0.825")
View attachment 401455

Taper cut with the compound
View attachment 401456

After a little polishing with a smooth file and 400-grit emery cloth
View attachment 401457

Test fit
View attachment 401458

Cutting the stress relief (?) groove
View attachment 401459


Next was turning the shank to diameter. I left a portion of 1” diameter stock at the base of the Jacobs taper for a bearing surface for the wedges in case the chuck needed to be removed from the arbor. Parted off with the band saw and faced/chamfered the end on the lathe.


Turning the shank to 3/4"
View attachment 401460

After a little polishing
View attachment 401461

Cutting off on the band saw
View attachment 401462

Faced and chamfered the 3/4" end
View attachment 401463


Then heat treated the arbor with a Thermolyne muffle furnace. After quenching, tempered to a dark orange (twist drill temper).


The Thermolyne takes about 30 minutes to get to 1550 F. Let it set for 10 minutes, then quench in motor oil.
View attachment 401464

Back into the furnace after quenching; tempered to a dark orange (~480 F)
View attachment 401465


Didn’t show it, but polished it up with a ScotchBrite wheel. Tapped it home with a brass hammer and there it is!


New arbor in the foreground
View attachment 401467

After a couple of taps with a brass hammer. In retrospect, I could have cut the taper a little smaller for deeper engagement.
View attachment 401468

View attachment 401469


Thanks for looking, Bruce

I want to learn how to do all that!!!