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jylong_away
05-23-2010, 08:12 AM
I'm planning to make a set of G10 scales for my Spyderco Manix 2 folder.

It has recessed flat head scale screws, and I was wondering if I could ask for advice about drilling the holes appropriately to have to screws flush with the scale? What kind of bit/method would be best to drill the wide portion for the head, and the narrow portion for the threads?

Am *very* new to knife making/modding, so please do forgive me if I sound totally blur about terminoloy, etc! Thanks!

Dave

Ernie Swanson
05-23-2010, 09:11 AM
The way I drill holes like this,

First drill the smaller hole all the way through, Then I Set the depth That I
want the larger hole and drill that, Not going to deep. I then take a drill bit of the same size as the large hole and grind the end flat. that squares up the bottom of the big hole.

A drill bit has a bevel to it and when you are drilling for a recess you want the point of the drill bit your very bottom of the larger diameter hole, making sure there is still enough material for the head to hold.
The reason I grind a drill bit flat is it will take out the bevel left by the regular drill bit so the head sits flat.

Hope this helps!!

BossDog
05-23-2010, 09:19 AM
there is a specific tool you are looking for is called a counterbore.
They have different size pilot holes and out diameters drill flutes that "bore" out the hole.
I have a few different sizes here... (http://www.usaknifemaker.com/store/index.php?main_page=advanced_search_result&search_in_description=1&keyword=counterbore)

stabber
05-23-2010, 09:31 AM
I was going to mention The counter Bore bit. The Boss got ya covered. ernie's way will certainly work also. Good point about useing the bit flat Ern

Ernie Swanson
05-23-2010, 10:23 AM
there is a specific tool you are looking for is called a counterbore.
They have different size pilot holes and out diameters drill flutes that "bore" out the hole.
I have a few different sizes here... (http://www.usaknifemaker.com/store/index.php?main_page=advanced_search_result&search_in_description=1&keyword=counterbore)

Hey I didnt even know they made those......... LOL Short Bus

jylong_away
05-23-2010, 02:15 PM
Thanks everyone for the tips.

Bossdog, I noticed the counterbore bits on your site as well as knifekits.com.

I believe the scale screws are actually flat head, with tapered necks, like these:

http://www.usaknifemaker.com/store/screw-080x14-flat-head-gold-plate-ss-100ct-p-1483.html

Is there an 82 degree version of the counterbore around at all?

Dave

BossDog
05-23-2010, 02:40 PM
I have never seen a counterbore with an 82 degree taper. There are countersinks with 82degree and you could find one slightly smaller than the size screw head and taper the bottom of the hole.

Ernie Swanson
05-23-2010, 03:50 PM
Thanks everyone for the tips.

Bossdog, I noticed the counterbore bits on your site as well as knifekits.com.

I believe the scale screws are actually flat head, with tapered necks, like these:

http://www.usaknifemaker.com/store/screw-080x14-flat-head-gold-plate-ss-100ct-p-1483.html

Is there an 82 degree version of the counterbore around at all?

Dave

Them style screws would just require a countersink to a depth where the screw head is flat.
for them you would not need a counterbore but a simple countersink.

EdCaffreyMS
05-23-2010, 04:17 PM
I would highly encourage you to use button head screws, and a counterbore if possible.
No matter how careful you think your being when drilling an 82 degree countersunk hole, it will ALWAYS be slightly off when you done. For a long time when I first tried building folders, I was trying to use 82 degree flat headed screws to keep things lined up....when you build a folder it gets taken apart and put together about a zillion times. The only way I solved my issue was to place two 1/16" hardened dowel pins through the liners and back spacer as alignment pins in each folder. The only reason the 82 degree screw holes are countersunk, is to make the top of the screw heads flush with the liners.

I personally like the carbide counterbores that MSC sells....they have interchangable pilots which means I can use them for a variety of different sized holes, and simply grind/turn the screw head down the required size.

jylong_away
05-23-2010, 08:56 PM
Thanks again to everyone for the amazingly quick and informative replies!

EdCaffreyMS: Will definitely keep that in mind. Still tossing up what kind of holes to drill - I'll likely be making more than one set of handles for this knife, so it may end up being a combination of both!

Tracy: Big order(for me, anyway!) headed your way. Was wondering about the counterbore for #4 & #6 screws - will the hole fit the button-head screws that are sold on your site for those sizes?

Thanks!

Dave