Drilling into TOUGH Soviet steel.....

[quikz 1]

I'm in the process of a PG conversion w/ krinkov style stock.

 

I can drill the rivets out easily with standard drill bits. But what do you all use for the trigger guard weld??? That steel is TOUGH and have gone thru 3 bits already. The trigger plate/guard is all off the rifle receiver right now.

 

Diamond/carbide tipped drill bits?

 

Thanks,

[oldandslow 3]

The trigger plate is off the rifle, heat it with a torch until red (Focus the heat on the spot weld). When it cools, it will be soft. Don't quench it (dip it in water). Let it cool to room temperature by itself. I use a propane torch.

[cellsworth 21]

I'm in the process of a PG conversion w/ krinkov style stock.

 

I can drill the rivets out easily with standard drill bits. But what do you all use for the trigger guard weld??? That steel is TOUGH and have gone thru 3 bits already. The trigger plate/guard is all off the rifle receiver right now.

 

Diamond/carbide tipped drill bits?

 

Thanks,

 

 

Cobalt alloy bits work very well.

[IndyArms 10,186]

I used a dremel with a special steel cutting bit, I think I paid like $12.00 for that ONE dremel bit... but it chewed thru that spotweld like a nice steak...

 

not butter... that would be too sloppy... but it still made quick work of it... LOL

 

 

[sicktooth 8]

+1 on the cobalt...it worked for me.

Edited July 22, 2008 by sicktooth

[chevymann 13]

I used center drill bits for the trigger guard spot weld.. Read that tip here somewhere.. I picked up a set of 5 for less than $15 off Amazon.

[Vultite 57]

Cobalt bits are good, but make sure you have a solid starting point for your bit otherwise a wandering bit will break. I started small and went up in size

[quikz 1]

Yep....I used a Cobalt drill bit from Home Depot, which WORE OUT QUICK! Made useless now by the Saiga.

 

Edited July 22, 2008 by quikz

[acercanto 6]

I don't remember who suggested it, but apparently, tile cutting carbide drill bits work well.

 

Acer

[moxie1c 3]

No problem here with cobalt bits.

[scoutjoe 276]

+1 on the Cobalt bits....go slow and use oil

[quikz 1]

I already drilled thru okay. Finished the Saiga conversion already:

 

Here's what it looks like http://forum.saiga-12.com/index.php?showtopic=28066 .....thanks everyone!

[Neurosis 0]

+1 on the Cobalt bits....go slow and use oil

 

Yup, what he said. I had put my cordless on the "1" setting and high torque instead of the drill setting, with a small container of used motor oil that I dipped the drill tip in every couple spins. I'll tell ya this though, I purchased the 3 piece center punch set from Home Depot and the durn Ruskie metal blunted all the tips.

[banshee 69]

more than likely you are running the drill to fast.

[NYMini 1]

I used a dremel with a special steel cutting bit, I think I paid like $12.00 for that ONE dremel bit... but it chewed thru that spotweld like a nice steak...

 

not butter... that would be too sloppy... but it still made quick work of it... LOL

 

+1

[schadenfreude 2]

The easiest method by far is the glass and tile bit. It's heaps faster than the cobalt bits. No going slow...... just do it.

 

I center punched it and drilled the bulk of it out in a few seconds and I was through the weld. Used a HSS bit to finish. Here are a few pics.

 

 

 

 

 

 

 

 

Edited July 24, 2008 by schadenfreude

[Azrial 1,091]

Those little make it hard to see what you are talking about.

[schadenfreude 2]

Those little make it hard to see what you are talking about.

 

 

Do you see any pictures at all? They aren't showing up for me

[skiboatsp 111]

The pics show a spade type carbide inserted tile drill

 

 

 

The #1 problem is heat, and as scoutjoe states spindle speeds

 

If the drill goes too fast for only a second it can burn the cutting surfaces and work harden the steel

 

The most pressure, thus more heat and it work hardens more and the drill dulls more

 

It's hard to control speed with a hand drill, but can be done

 

In a press run about 200 - 300 rpm and use oil

 

The oil lubricates and helps with the transfer of heat into the chip

 

the reason center drills work better is it has a heavy duty flut profile and material behind the cutting surfaces to absorb more heat before the edges burn.

 

Carbide tools work because they can tolerate more heat and are harder, but much more brittle.

 

Try the HSS or cobalt tools with proper speeds and if it burns ( stops cutting consistant chip ) then go to carbide

 

The spot welds are harder than the surrounding material because the heat alters the hardness of the steel.

Edited July 25, 2008 by skiboatsp

[Azrial 1,091]

Do you see any pictures at all? They aren't showing up for me.

They are showing up now, thanks!

[tubebeast 0]

when i did mine i got most of the way though it and just kind of pryed it off