Good quality solid carbide bits

[tkerrigan]

I would like to drill a #46 or #45 or 2.1MM hole about .5" deep in a Grizzly chuck jaw to use for winding hammer springs on transfer punches.  Just bend a 90° on the end of the wire and stick it in the hole.  This would save a bunch of time over turning mandrels trying to find the right size to get the spring you are after. What I wold like to know would be the best speed to drill at and the best brand of bit to hopefully not break.  I will be using a milling machine to drill the hole.  Regards, Tom   

[GSu]

Try here:
https://www.kodiakcuttingtools.com/
Use their carbide bits to drill tempered spring steel speargun shafts.

[mobilehomer]

We used these where I worked.
https://www.kbctools.com/products/search/carbide%20drill?v=j&facet=%5B%5B%22catname%22%2C%22catname%22%2C%22Circuit%20Board%22%5D%5D

[Nvreloader]

Tom

Do you know if the jaws are hardened, take a good file and see if you can mark it, you may not need Carbide bits,
get a good bit for drilling screws out, should work just fine.........

I run my carbide drill bits at a fairly high rpm and use a light touch for down pressure,
with the size you want to use, 700-800 rpm should be about right, you can feel when you get it right,
it will fall thru like hot butter.........don't get heavy handed, ..just a couple of fingers will do.........

Do you have a Machinist Handbook, worth there weight in gold, kinda expensive when first bought,
has all kinds of info inside.............. even info on turning springs etc.

HTH's

Tia,
Don

[Insanity]

I am interesting in knowing how hard the steel the jaws on a grizzly chuck is. I would want to beleave they are some sort of tool steel that should still be able to be drilled with a good bit but will take some doing.

[tkerrigan]

I ordered two #46 coated from Kodiak.  Thanks for every bodies help. I will post back when I try them out.  Regards, Tom

[Nvreloader]

Matt,
I would believe that the jaws could be cast steel, Grizzly is an over seas machine,
if you can mark the jaw with a file, then the jaws are not that hard,
and the biggest problem with carbide is using too low of speed, carbide works very well at higher speeds..

A carbide drill bit should walk right thru a jaw, I would drill a thru hole, that way if something goes wrong,
and you have a piece of wire broke off in the hole, you can drift it out, instead of dealing with a blind hole situation etc.

https://www.ebay.com/itm/082-45-Carbide-Drill-Bits-1-8-Shank-FIVE-Pcs-CNC-Dremel-Model-Hobby-RS/161541540871?

https://www.ebay.com/itm/45-0820-JOBBER-STD-SOLID-CARBIDE-25DEG-HELIX-118DEG-SPLIT-PT-DRILL-BIT-NEW/292135009366?hash=item44049a7c56:g:onsAAOxypthRt31z:sc:USPSFirstClass!89419!US!-1

https://www.ebay.com/itm/46-0810-SOLID-CARBIDE-STRAIGHT-FLUTE-140DEG-NOTCHED-POINT-DRILL-BIT-NEW/121740321505?hash=item1c5849e2e1:g:YqwAAOxyepRRtyRN:sc:USPSFirstClass!89419!US!-1

Here are some of the carbide drill bits I use in my mill,

HTH's

Tia,
Don

[tkerrigan]

I have the 27th edition of Machinerys hand book as a download if anybody wants a copy.  The chuck jaws were hard enough that I could just mark it with a 1/8" high speed steel end mill, it made a depression about .010" deep and wouldn't go any further.  I ordered a couple of Kodiak coated #46 solid carbide bits, so we will see.  I will post back the results. I do like the idea of drilling all the way through, I'll see how easy it drills.   Regards, Tom

[Insanity]

Well those should get the job done. I agree drill a through hole so you can drift out a potential broken bit.

[glassman98]

Tom, get a set of Alum soft jaws, then you can use HS drills, and they can be used for all sort of turning. Craig

[tkerrigan]

If the carbide bits don't work out, I'll try making a set of aluminum jaws.  For what I want to do, they don't need to be super precision. Thanks for the idea.   Regards, Tom

[tkerrigan]

I drilled through the chuck jaw this morning, all the way.  It was hardened more towards the outside .1" or so.  It was pretty hard in the interior also, very small chips, no strings.  It was about 1.75", the last .125" was done with .1875" of shank in the chuck.  I ran the bit at about 2000rpm no lube in a Harbor Freight small milling machine.  Regards, Tom

[tkerrigan]

I drilled through the chuck jaw this morning, all the way.  It was hardened more towards the outside .1" or so.  It was pretty hard in the interior also, very small chips, no strings.  It was about 1.75", the last .125" was done with .1875" of shank in the chuck.  I ran the bit at about 2000rpm no lube in a Harbor Freight small milling machine.  Regards, Tom

[Bill G]

Can you use interchangeable jaws on your chuck? If so, buy soft jaws. Drill a hole through the smallest I.D. step of the jaw to accommodate a 1/4-20 set screw. Then cut a slot in the contact face of the jaw that will accept the range of wire diameters you anticipate using. With this , you can place a mandrel in the jaws firmly and insert wire into the slot, holding the wire with the set screw. This allows it all to run very true and consistent. With this set-up, you can also use a split collar with a slot and set screw to establish tails for hooks and such. I've even used my feed to make consistent windings in 4 and 4 1/2 pitch. Drilling hard jaws is a PIA. Even cheaper than the soft jaws would be a mandrel that has a large o.d. with a set of small holes, in various wire gauge, around the face of the shoulder. The smaller o.d. (actual mandrel) would need to be a screw in o the larger part (held in the jaws). These methods can afford you a little more stand off from the chuck, especially the method with the collars.
The soft jaws will probably cost you about what the carbide will cost. The others methods you could make. Although, I'd buy the collars and modify them.

Hope that helps
Bill

[Bill G]

 :-[Ishould have read all the posts.......duh. jobs done. Good job btw.