Hammer A3 quick & cheap power table drive

[Mick Simon]

Here a link to a video I made of a quick and easy fix for having to crank the wheel 147 times to raise the table to the average working height.

https://www.youtube.com/watch?v=veJPpksmW8w

Made from scrap 3/4" plywood and a 5/16" x 2" carriage bolt. I picked up a $10 drill from HF and leave it chucked up in it beside my A3-41.

[David Wong]

That’s very slick. So in addition to the slot on the disk for the wheel handle, you register two pins into holes you drilled in the wheel?

[Chris Parks]

^ yep, what he said, if it was just three spokes or even a straight bar you should be able to see the in handle dial.

[Mick Simon]

^ yep, what he said, if it was just three spokes or even a straight bar you should be able to see the in handle dial.

I opted for the studs because it was more rigid. I tinkered with spokes so I could see the dial, but in practice it was awkward and not necessary. I can stop it within a couple of turns of the handwheel by looking at the supplied scale and then dial it in using the gauge.

[Mick Simon]

That’s very slick. So in addition to the slot on the disk for the wheel handle, you register two pins into holes you drilled in the wheel?

Yes. I took the wheel off and removed the knob and gauge, then used the wheel to layout the diameter on the plywood. I bandsawed that to rough shape, double face taped it to the wheel and used a flush trim bit on my router table to clean it up. Switched to a roundover bit to ease the edges. With it still taped together, I laid out two 3/8" holes on the backside of the wheel where its flat at 120 degrees apart. I also copied the hole location for the knob bolt. I took it to the drill press and drilled through the aluminum about 3/8" into the plywood. I separated the parts, located the center and countersunk a 3/4" hole for the carriage blot then drilled it out with a 5/16" bit for the bolt. I epoxied two 3/8" x 5/8" sections of aluminum rod I had from another project into the 2 120 degree holes. I made the slot using a 7/8" Forstner and finishing it on the bandsaw.

370970
370969

[Prashun Patel]

Thanks for this thread. That is an elegant solution.

[Derek Cohen]

Mick, I think this is brilliant!

I decided to knock a jig up quickly .. more as a proof of concept, as I have an idea to improve the design.

There was a small aluminium disc in my salvage box, once used as a sanding plate ...

https://s19.postimg.org/71btdxyar/1.jpg

The rear (which was the face in its previous life) was velcro ...

https://s19.postimg.org/pgwabcrur/2.jpg

... which is how I decided to attach it as I did not want anything permanent (at this stage) ...

https://s19.postimg.org/akxr3r8qb/3.jpg

Stuck on, and a drill connected, it worked rapidly ....

https://s19.postimg.org/478o0ij9v/4.jpg

One idea is that it can be unclipped and stored inside the machine ...

https://s19.postimg.org/sazfot9gj/5.jpg

Here's my idea: make the front plate out of clear Lexan, attach a bolt through the centre - that will allow the dial to be seen clearly with a drill attached - and bolt it to the wheel.

Regards from Perth

Derek

[John Gornall]

A socket adapter and socket on the drill to drive a nut rather than chucking and unchucking

The handle on the wheel is for major adjustment such as changeovers but with power drive could be removed - fine adjustment with handwheel alone

Lexan - that would be plexiglass

[Mick Simon]

A socket adapter and socket on the drill to drive a nut rather than chucking and unchucking

The handle on the wheel is for major adjustment such as changeovers but with power drive could be removed - fine adjustment with handwheel alone

Lexan - that would be plexiglass

The socket is a good idea. I just leave mine chucked up in a $10 HF drill. I agree on the gross vs fine adjustment. That's exactly what I do. I've found I can stop within a revolution or so of the final adjustment.

[Jamie Buxton]

That's an excellent approach.

I started to build one for myself, but modified it a bit. My version doesn't use the OP's metal drive pins, but uses wood fingers that grasp the planer's handwheel around the outside edge. The fingers are tapered at the tip, so the device easily self-aligns as I shove it on to the handwheel.

I think my version is easier to build; I never took the handwheel off the planer, and didn't drill any holes into it either.

371024

371025

[mreza Salav]

Nice ideas. Is it true that the hand-wheel moves up/down with the table? My Minimax J/P has the handwheel in the base (fixed place).

[Dan Friedrichs]

Lol - Jamie, your solution is the complete philosophical opposite of what I did (http://www.sawmillcreek.org/showthread.php?253281-DIY-PowerDrive-electronic-table-raise-lower-for-a-Hammer-A3-31&highlight=). I like the tapered wedge idea, though - very elegant!