drill bits

Started by Donnyboat, November 22, 2018, 02:02:32 AM

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Frank

#60
Quote from: Tiddlerbasher on November 28, 2018, 07:04:49 PM
Centre punch then hss centre drill (stubby no flex thing) to start the hole. Then Hss (Co) for stainless or plain Hss for Aluminium/Brass/Mild steel. I only use brad points (carbon steel) on wood.
Carbide tipped bits work on pretty much anything but they are not particularly accurate and can wander - ok for masonry though.

For dimensional accuracy (tapping or bearing fit) I use drill bits complying with DIN338 RN - more expensive but if it needs to be accurate so be it.

Thank you. Saving all this info in my Alan Tani special folder.
Frank. Retired. Life long fishing and boating fanatic.

Three se7ens

Quote from: Frank on November 28, 2018, 06:46:32 PM
Thanks for all the information on reel bits guys. It really cleared up a lot of misconceptions I had from the past. The most obvious is the benefits of using stubby bits due to less flex.

Is there such a thing as a heavy duty stainless/aluminum cutting brad point tip? I use the brad points on fiberglass and 1/2" plate aluminum boat transoms when drilling for outboard motor brackets and I want to make sure the bit doesn't walk. I start off with the brad point and once the hole is deep enough I switch to a cobalt regular bit to complete the process.

Frank

Brad tip bits are used in wood and composites to minimize fraying on the back side of the hole.  That is not an issue with metal, but that fine, sharp point would be subjected to heavy wear in metals. 

Center drills arent actually designed for starting holes, they are for putting in a tapered hole to use with lathe centers.  Now, they work well because they are very stiff and rigid, but that wasnt their original purpose.  The actual drills for starting/marking holes are more commonly referred to as spotting drills.  https://www.mcmaster.com/spotting-drills  Not a lot of use outside a machine shop, and even that is on the down swing with modern high performance drill bits. 

Unless you need the long length, go with a screw machine style bit instead of the normal jobbers length.  Generally, you will not need to center drill a screw machine length bit, but almost certainly will for a jobbers length bit.

Frank

Quote from: Three se7ens on November 29, 2018, 12:35:36 AM
Quote from: Frank on November 28, 2018, 06:46:32 PM
Thanks for all the information on reel bits guys. It really cleared up a lot of misconceptions I had from the past. The most obvious is the benefits of using stubby bits due to less flex.

Is there such a thing as a heavy duty stainless/aluminum cutting brad point tip? I use the brad points on fiberglass and 1/2" plate aluminum boat transoms when drilling for outboard motor brackets and I want to make sure the bit doesn't walk. I start off with the brad point and once the hole is deep enough I switch to a cobalt regular bit to complete the process.

Frank

Brad tip bits are used in wood and composites to minimize fraying on the back side of the hole.  That is not an issue with metal, but that fine, sharp point would be subjected to heavy wear in metals. 

Center drills arent actually designed for starting holes, they are for putting in a tapered hole to use with lathe centers.  Now, they work well because they are very stiff and rigid, but that wasnt their original purpose.  The actual drills for starting/marking holes are more commonly referred to as spotting drills.  https://www.mcmaster.com/spotting-drills  Not a lot of use outside a machine shop, and even that is on the down swing with modern high performance drill bits. 

Unless you need the long length, go with a screw machine style bit instead of the normal jobbers length.  Generally, you will not need to center drill a screw machine length bit, but almost certainly will for a jobbers length bit.

Thanks so much for taking the time to post that info.

Best

Frank
Frank. Retired. Life long fishing and boating fanatic.

Reel 224

Quote from: Frank on November 29, 2018, 02:38:03 AM
Quote from: Three se7ens on November 29, 2018, 12:35:36 AM
Quote from: Frank on November 28, 2018, 06:46:32 PM
Thanks for all the information on reel bits guys. It really cleared up a lot of misconceptions I had from the past. The most obvious is the benefits of using stubby bits due to less flex.

Is there such a thing as a heavy duty stainless/aluminum cutting brad point tip? I use the brad points on fiberglass and 1/2" plate aluminum boat transoms when drilling for outboard motor brackets and I want to make sure the bit doesn't walk. I start off with the brad point and once the hole is deep enough I switch to a cobalt regular bit to complete the process.

Frank

Brad tip bits are used in wood and composites to minimize fraying on the back side of the hole.  That is not an issue with metal, but that fine, sharp point would be subjected to heavy wear in metals. 

Center drills arent actually designed for starting holes, they are for putting in a tapered hole to use with lathe centers.  Now, they work well because they are very stiff and rigid, but that wasnt their original purpose.  The actual drills for starting/marking holes are more commonly referred to as spotting drills.  https://www.mcmaster.com/spotting-drills  Not a lot of use outside a machine shop, and even that is on the down swing with modern high performance drill bits. 

Unless you need the long length, go with a screw machine style bit instead of the normal jobbers length.  Generally, you will not need to center drill a screw machine length bit, but almost certainly will for a jobbers length bit.

Thanks so much for taking the time to post that info.

Best

Frank

Frank: Adam is one of those guys that will guide you in the rite direction, I hadn't thought of the spotting bit.........................Joe 
"I don't know the key to success,but the key to failure is trying to please everyone."

Dominick

I ordered a bunch from Mc Masters Carr as Master Sal suggested.  Thanks all for your responses.  Dominick
Leave the gun.  Take the cannolis.

There are two things I don't like about fishing.  Getting up early in the morning and boats.  The rest of it is fun.

Reel 224

Quote from: Dominick on November 29, 2018, 03:47:24 AM
I ordered a bunch from Mc Masters Carr as Master Sal suggested.  Thanks all for your responses.  Dominick

I see Sal can spend your money very well  ;D ;D ;D............................Joe
"I don't know the key to success,but the key to failure is trying to please everyone."

Dominick

Yep, they were not cheap, but at my age my kids will have to deal with them.  Dominick
Leave the gun.  Take the cannolis.

There are two things I don't like about fishing.  Getting up early in the morning and boats.  The rest of it is fun.

Donnyboat

Gee Wizz, you good people really look after me, I ask a simple question about drill bits & get 66 replies, so now I know a bit about drill bits, what is the best vice or clamp to hold the part that you wish to drill, especially  when your trying to drill into a thin piece of rod, I have a good drill press for the bit, I guess this is where a lathe comes in handy, but cant afford a lathe, cheers Don.
Don, or donnyboat

Reel 224

Quote from: Donnyboat on November 30, 2018, 03:41:33 AM
Gee Wizz, you good people really look after me, I ask a simple question about drill bits & get 66 replies, so now I know a bit about drill bits, what is the best vice or clamp to hold the part that you wish to drill, especially  when your trying to drill into a thin piece of rod, I have a good drill press for the bit, I guess this is where a lathe comes in handy, but cant afford a lathe, cheers Don.

A V block would be the thing you need, they make them for drilling tubing.https://littlemachineshop.com/products/product_view.php?ProductID=2186&category=

Joe
"I don't know the key to success,but the key to failure is trying to please everyone."

Donnyboat

Thanks Joe, thats one good idea, but I was talking of standing a piece of rod vertical, & drilling down the centre of the rod, thanks again, cheers Don.
Don, or donnyboat

Reel 224

Quote from: Donnyboat on November 30, 2018, 03:36:35 PM
Thanks Joe, thats one good idea, but I was talking of standing a piece of rod vertical, & drilling down the centre of the rod, thanks again, cheers Don.

How deep are you going, and what ID are to trying to achieve?             Joe 
"I don't know the key to success,but the key to failure is trying to please everyone."

Donnyboat

Thanks Joe, ? to both questions, my drill press, clamp, does not have any provition, to stand any thing vertical, that can be succured to have it stand straight up & not move with any pressure on it, cheers Don.
Don, or donnyboat

STRIPER LOU

Hi Donny,

Can you rotate the table out of the way on your drill press and drill off the base plate for extra height?
I do it here all the time with long stuff. it might be easier if we knew what you had. Joe's suggestion with the V block is a good one and can even be used along with a vise for simple clamping. I have a universal block that I built probably 40 years ago and still use it today.

If there's any interest, I can post a picture.

Regard's  ....................Lou

Donnyboat

Thanks Lou & Joe, your both sticking with me, witch is great, Lou the drill stand & press that I have, is a Borum 16 speed with A 5/8 or 16mm chuck, yes the table can be pivoted both ways, right out of the way if necessary, also the clamp  that I am using is 5 inches, or 123 mm wide, I am thinking of maybe closing the clamp right up, then drilling a small hole, down through the centre, then Veeing it out, that should hold a piece of rod, verticle, I wish I could post pictures, but have tried many times, with know luck, Joe Decker was kind enough to make up a video for me @ one stage, I am using windows 10 micro soft computer with google chrome & so on, but when I try step by step as Joe & Josa 1, have explained, the computer just does not follow the com,cheers for now Don.
Don, or donnyboat

kmstorm64

Quote from: Three se7ens on November 23, 2018, 05:38:35 AM
Avoid carbon steel drill bits unless you are drilling wood.  For everything else, get HSS or cobalt.  Carbon steel will lose its temper first time it gets too hot, and it will never hold an edge after, even with sharpening.  HSS will hold its temper through cherry red heat, and they are still somewhat flexible/forgiving.  Cobalt is harder and holds an edge better, but is more brittle.  Cobalt generally works better in stainless and other tough alloys, but HSS is more forgiving. 

Stainless (and titanium, and a number of other metals) work harden.  So if you are drilling without making chips, you are only making the material harder.  The name of the game here is slow and heavy pressure.  Keep in mind, this is all relative.  A 1/4" drill but still needs to run faster, and with less pressure than a 1" drill bit. 

I could get complicated with speed/feed charts like machine shops use, but its not necessary.  Shops need to make money, and weigh productivity vs tool life.  For everyone else, its usually better just to go slower and get far longer tool life.  So go slow enough and heavy enough to get a good, consistent chip from the drill.  That will get you close enough for most. 

I have a set of Cobalts I bought when I was stationed in Ital y in 1987, damn things are still  going strong. I also have a set of Carburetor fine wire drill bits.  These are soft, but great for cleaning out small holes. They are used in a pin vice, and turned slowly. they can do things when you need that fine to very fine cleaning tip.  Also pipe cleaners can be a godsend for working on reels.
Bad day of fishing still beats a good day at work!