centered drill bits &/Or countersink bits

[Slappy]

anyone suggest a good quality but inexpensive fractional set of centering tools for drill bits  ,

I have some thing I need to mount  that has 1/4" holes along the edges  that I would have to then place  the item up against the 3/4" oak plywood & drill a centered pilot hole for a sinking a threaded stud into the hole .
the stud is wood screw threads on one end & then 1/4x20 bolt threads on the other end So the drill size is just smaller to allow for the threads to get a good bite
the hole needs  to be centered ,  square & true perpendicular ,
as if not the the bolts will not line up correctly to the mounts holes (there are 10 such holes/bolts  )

the item's mounts edge is 3/4" deep as well . So once the item is  mounted the studs would protrude thru the items & have enuff threads to put a nut & washer on it .

I am looking for a set of counter sinks as well . that would cut AL & hardwoods

it seems that price on these items are wildly different , I'm looking for Best Bang for the Buck , but want a tools that will last well  beyond this project .

 

[Michael Kellough]

What in the world needs ten 1/4 screws to hang itself from wood?  [eek]

Please post a picture or link...

 

[Slappy]

this is a MDF speaker horn assembly , it will mount in speaker cab from the inside .
As the horn cost WAY more that the cabinet costs I want to be able to remove if & when I change up the cab design
the horn is made on CNC in 3/4" layers & the glue together , the mount holes are CNC'ed as well .
it's made to fit in to a opening & the sit flush with the outer surface of the speaker .
I biuld the horn from a kit & did all the assy,sanding & finish work by hand  there are 9 of these to be mount in cabs .
So you can see that I need a constituent way to mount & then be able to remove the horn if I need to change the HF compression driver at the horn's  opening .
I don't want to just use a big wood screw as the holes in the speaker cabinet wouldn't take many removals & re-installs before stripping out   

 

[bkharman]

Could you rig up some sort of french cleat on tops and bottoms?  May make it easier in all aspects to work with...

cheers

 

[Slappy]

Could you rig up some sort of french cleat on tops and bottoms?  May make it easier in all aspects to work with...

cheers

That is a excellent idea !
Yeah I was thinking maybe use dowels glued into the cab to match the  holes, that way the horn would just align & sit on the dowels  & then use  cleats to clamp the horn tightly to the cabinet  .
It has to sit tight as there's a huge 15" woofer just below this horn .
I don't want to alter the horn on anyway ,as the destroys the resell value in the future in the horn is only valuable as is

 

[tjbnwi]

Check your Vix bits. I have this one, the O.D. of the barrel is 0.245.

http://www.mcfeelys.com/product/MS-5105/Snappy-564quot-Self-Centering-Bit

Tom

 

[ca90ss]

To mark the holes something like this should work
http://www.amazon.com/gp/product/B002BFTSNM/ref=oh_details_o08_s00_i00?ie=UTF8&psc=1

I would use something like this to screw them in with
http://www.mcfeelys.com/product/3606-STS/14-20-Steel-Threaded-Inserts

 

[Slappy]

I would use something like this to screw them in with
http://www.mcfeelys.com/product/3606-STS/14-20-Steel-Threaded-Inserts

these will WORK !  I can predrill  a  1/4 " hole with the horn in place on all the holes at once , then remove horn then enlarge the holes slightly with a larger drill bit
insert these with a Allen wrench then use a 1/4-20 screw/ bolt the secure the horn
I've never seen these that are all steel (not cast pot metal or brass as usual ) & then will  set with a Allen wrench ,

A Hard Job just got really simple ThanX   ca90ss

AND the're on SALE as well

I just bought a 100 of them
they had a Very Cool driver for them Too!  so you can't over drive them into a hole

http://www.mcfeelys.com/product/9000-PD/6mm-Hex-Driver-for-14-20-Inserts

 

[Samo]

You will find other uses for that style connector.

Very handy for prefinished shelving and carcass stuff that you may want to break down later.

[big grin]

 

[Slappy]

You will find other uses for that style connector.

Very handy for prefinished shelving and carcass stuff that you may want to break down later.

[big grin]

I can see that they'd very handy on Ho'made jigs  [wink]

 

[leer]

I'd also check out Lee Valley for drill bits and countersinks.  Their single flute countersinks work great.  I've ordered lots of hardware items from them, too, over the years.  I had an old oak filing cabinet that needed new pulls, and I needed to match the spacing of the holes for the pulls.  I found a design that came in maybe a dozen different sizes, so I could get exactly the spacing I needed.  Be sure to ask for their tool catalog, and their hardware catalog.  If you are in to gardening, get their gardening catalog also.

Lee Valley produces some of the nicest catalogs I've ever seen -- always have cool pictures on the covers.  My wife uses them for coffee table art ...