Drill and tap

[thetruecheese]

Hey guys i have a scope mount for my SKS here i need two drill and tapped holes my smith wanted 75 per hole holy crap! Anyone have a suggestion for a smith in the sf bay area? I figure i could buy a damn drill press and bits and probably do it myself for the 150 bucks. Never done a drill and tap is this something i should be able to do myself without much trouble? I hear these chinese steels are very hard which makes it a bit more difficult.

Thanks

[canid]

I figure i could buy a damn drill press and bits and probably do it myself for the 150 bucks. Never done a drill and tap

Your gunsmith has, knows they can do it competently, and is guaranteeing his or her results. This is where the money is going.

You can absolutely drill and tap some holes yourself. Can you be sure you don't mis-drill or break a tap off in your receiver? It's your firearm; it's your call.

[sonofeugene]

Peoples time and experience is worth money. Given the material being drilled and tapped into, the price is more than reasonable.

Drilling and tapping is NOT as easy as most think. You could try it yourself, but I'd bet a large amount of money you'd screw it up and likely ruin your SKS. And there are plenty of ways to screw it up.

Holes in wrong location.
Holes crooked.
Drilling too far into something you shouldn't have drilled into.
Breaking a drill in a hole.
Breaking a tap in a hole.
Not making the threads deep enough and breaking a screw in a hole.
Etc.....

[sonofeugene]

And 150 bucks is NOT going to get you a decent drill press, the fixturing and tools needed to hold the part, a quality drill and tap, cutting fluid, and equally important, the knowledge and experience.

Learning to drill and tap is fine. Just don't learn on something that will be expensive if you screw up.

[milotrain]

Listen to the above. There is a reason the smith is charging you $75 per hole. You could certainly do it yourself for $150, you will be lucky if you don't ruin your SKS and you should play powerball if you do the job successfully.

Try this first, get a piece of scrap steel and drill and tap two holes in it for your scope mount, then mount the scope. Respond to this thread with questions you run into while you are doing this and pictures. Then you'll know if you want to bother with the SKS or pay the smith to do the work. Obviously you'll be out at least $300 at this point but you won't have a ruined rifle.

[kcstott]

I'll sell you the tap and drill bit you need for $10, go ahead give it a go.. like you said you've never drilled and taped anything let alone tool steel, How hard could it possibly be?? (About 45Rc to be exact) By the way removing a broken tap cost double what tapping the hole costs. Fixing cockeyed holes costs more then removing broken taps.. So go for it, have a go...

[chuckshooter]

don't you just need this

[thetruecheese]

Absolute sour grapes. Heaven forbid i want to ask about the difficulty of drilling and tapping, besides a bunch of snickering about making sure the holes are drilled in the right spot (DUH!). I'm perfectly willing to give it a go and learn some new skills that could be useful in the future, as well as tooling.
The tapping will need to be done with M3-.5 screw pitch. Are there any special concerns i should keep in mind for doing it to a rifle like this in particular? I was going to drill though all the way the reciever on the mounting points first. It would appear i need a 2.5mm bit to drill through first, then follow with the tap, using generous oil and going slow at a fast speed? I can buy these bits for dirt cheap on ebay to do a couple practices with some scrap metal. The sks in particular i think will be easier due to the square nature of the reciever which is going to reduce the need for dedicated fixturing to a great margin. Also can always shim any error out or on my combloc scope mount has the ability to adjust for slight angular error too, it's for a side-mount scope not a rail. Would appreciate any actual advice
Thanks

[kcstott]

Absolute sour grapes. Heaven forbid i want to ask about the difficulty of drilling and tapping, besides a bunch of snickering about making sure the holes are drilled in the right spot (DUH!). I'm perfectly willing to give it a go and learn some new skills that could be useful in the future, as well as tooling.
The tapping will need to be done with M3-.5 screw pitch. Are there any special concerns i should keep in mind for doing it to a rifle like this in particular? I was going to drill though all the way the reciever on the mounting points first. It would appear i need a 2.5mm bit to drill through first, then follow with the tap, using generous oil and going slow at a fast speed? I can buy these bits for dirt cheap on ebay to do a couple practices with some scrap metal. The sks in particular i think will be easier due to the square nature of the reciever which is going to reduce the need for dedicated fixturing to a great margin. Also can always shim any error out or on my combloc scope mount has the ability to adjust for slight angular error too, it's for a side-mount scope not a rail. Would appreciate any actual advice
Thanks

Well you said you never drilled and taped anything, and drilling and tapping a rifle receiver in not exactly the first project i'd choose to try.

you want advice and you don't bother to mention a word about what you have for tooling..

Help us out and we'll help you. but be advised this is going to be and up hill challenge.

[canid]

I think you're getting plenty of encouragement, just good advice to learn to do the job first and a reasonable explanation about the costs involved in having the work done professionally.

Tradesmen charge, and experienced tradesmen know not to undervalue their work.

There's still no reason you can't proceed on your own; if nothing else a drill press is a tool everybody with a garage or shop should own anyway.

[ar15barrels]

150 bucks is NOT going to get you a decent drill press, the fixturing and tools needed to hold the part, a quality drill and tap, cutting fluid, and equally important, the knowledge and experience.

Those last two are really expensive and time consuming to obtain.

[sonofeugene]

I'll sell you the tap and drill bit you need for $10, go ahead give it a go.. like you said you've never drilled and taped anything let alone tool steel, How hard could it possibly be?? (About 45Rc to be exact) By the way removing a broken tap cost double what tapping the hole costs. Fixing cockeyed holes costs more then removing broken taps.. So go for it, have a go...

10 bucks won't buy a proper drill and tap.

[sonofeugene]

Absolute sour grapes. Heaven forbid i want to ask about the difficulty of drilling and tapping, besides a bunch of snickering about making sure the holes are drilled in the right spot (DUH!). I'm perfectly willing to give it a go and learn some new skills that could be useful in the future, as well as tooling.
The tapping will need to be done with M3-.5 screw pitch. Are there any special concerns i should keep in mind for doing it to a rifle like this in particular? I was going to drill though all the way the reciever on the mounting points first. It would appear i need a 2.5mm bit to drill through first, then follow with the tap, using generous oil and going slow at a fast speed? I can buy these bits for dirt cheap on ebay to do a couple practices with some scrap metal. The sks in particular i think will be easier due to the square nature of the reciever which is going to reduce the need for dedicated fixturing to a great margin. Also can always shim any error out or on my combloc scope mount has the ability to adjust for slight angular error too, it's for a side-mount scope not a rail. Would appreciate any actual advice
Thanks

Good on you for wanting to do it yourself, but seriously, find some suitable scrap steel of the same thickness to practice on. And make more than just a couple test holes. Good luck!

[kcstott]

10 bucks won't buy a proper drill and tap.

You don't know where to shop. when you buy drills by the dozen they run about $2 each, a 6-48 tap is $6 an 8-40 is is $8 but you have to buy in bulk to get that price.

[bishop2queen's6]

Drilling and tapping are skills a part of a learned and, most importantly, practiced trade.

I have access to some of the more high end drill presses and Daps, taps, punches, dies, and I still get it wrong on occasion b/c it's not my trade.

It's harder to drill and tap with something that fine b/c there is little room for error. You'll more than likely break a tap, strip some threads, and ruin your mount.

As a hobbiest, sure, give it a shot, but can you live with the results if you can, and will screw it up.

My advice, leave it to the pros. There is a reason why he charges that seamingly absurd rate of which every penny he deserves.