Quality 10 mm SDS plus bits?

[wbgiff]

i’ve searched, high and low (eBay, Amazon, etc.). But I can’t find German made SDS bits in 10 mm lots of 3/8” but that’s 25 thou too small for my 10mm Sierra blaster charges. Sierra sells bits but they are not doing too well. In the super high compressive strength rock I’m dealing with. If I’m lucky I can get 10 inches of penetration per bit. Sometimes they fail much faster. I assume the bit Sierra sells is Chinese manufacturer, but I can’t tell for sure.

 

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[Assembler]

i’ve searched, high and low (eBay, Amazon, etc.). But I can’t find German made SDS bits in 10 mm lots of 3/8” but that’s 25 thou too small for my 10mm Sierra blaster charges. Sierra sells bits but they are not doing too well. In the super high compressive strength rock I’m dealing with. If I’m lucky I can get 10 inches of penetration per bit. Sometimes they fail much faster. I assume the bit Sierra sells is Chinese manufacturer, but I can’t tell for sure.

Metric SDS+ 10MM x 10" (Each) $21.22

https://www.toolsboltsnbits.com/sho...-14/bits-c-14_34/sds-metric-bits-c-14_34_335/

Granite V Tip Bit 3/8 x 4

(3 per Pack) $16.71

https://www.toolsboltsnbits.com/sho...14_34/granite-vtip-bit-hex-shank-c-14_34_353/


1-1/2"x 22" Spline Core Bit

(EACH) HC8005 $219.21

https://www.toolsboltsnbits.com/sho...14/bits-c-14_34/spline-core-bits-c-14_34_110/

1-1/4" x 12" LongBoy Bit 1/2 Shank (Each) $162.30

https://www.toolsboltsnbits.com/sho...-c-14/bits-c-14_34/long-boy-bits-c-14_34_465/

1/4" x 24" Aircraft Bit (3 per Pack) 2-3/4" Flute $89.40

https://www.toolsboltsnbits.com/sho...s-c-14/bits-c-14_34/aircraft-bits-c-14_34_99/

Annular Cobalt Cutter Bits 7/16" x 1" (Each) 12214 $29.31

https://www.toolsboltsnbits.com/sho...14_34/annular-cobalt-cutter-bits-c-14_34_327/

1-1/2"x 22" SDS Max One Pc Core Bit (EACH) $208.43

https://www.toolsboltsnbits.com/sho...4/bits-c-14_34/sds-max-core-bits-c-14_34_109/

 

[Mountaineer2020]

i’ve searched, high and low (eBay, Amazon, etc.). But I can’t find German made SDS bits in 10 mm lots of 3/8” but that’s 25 thou too small for my 10mm Sierra blaster charges. Sierra sells bits but they are not doing too well. In the super high compressive strength rock I’m dealing with. If I’m lucky I can get 10 inches of penetration per bit. Sometimes they fail much faster. I assume the bit Sierra sells is Chinese manufacturer, but I can’t tell for sure.

I use the sierra bits and haven't had one fail yet probably around 50 or so holes and counting. Maybe your rock is absolutely horrible compared to what I've been in. I use 3 small bits, 2 medium and 2 large for the tough holes rotating them out to keep them cool. It's a pain but they change quick and keeps them from getting too hot and losing their temper. Have dipped them in water for cooling too but that tends to gunk up the hole with grit which makes it tough to get the cartridge down there. Although if you have enough water to pour in at the end it seems to work ok.

 

[Assembler]

I use the sierra bits and haven't had one fail yet probably around 50 or so holes and counting. Maybe your rock is absolutely horrible compared to what I've been in. I use 3 small bits, 2 medium and 2 large for the tough holes rotating them out to keep them cool. It's a pain but they change quick and keeps them from getting too hot and losing their temper. Have dipped them in water for cooling too but that tends to gunk up the hole with grit which makes it tough to get the cartridge down there. Although if you have enough water to pour in at the end it seems to work ok.

Rotating the drills will make a big difference. My two cents to add is to add few ounces of water down the hole when you change the drill bits to cool the rock around the hole and the drill for a while as the water boils off.

 

[russau]

Why don't you check the hardness ( Rockwell) of these bits when new to see if they are up to the task ? If they aren't up to the task why not re-harden them up to what you need ?

 

[wbgiff]

Here’s the thing,

Im told this is norcal andesite <sic>? aka blue granite.. It is almost 8 mohs. The shards sound like glass/porcelain when shoveled. Sometimes the sierra bits fail in 30 seconds of use. Sometimes i can get a few holes, sometimes only 1. I baby them, rotate bits (6”, to 12, to 18, to 20) doesnt matter, they are simply not built to handle rock with this compressive strength and hardness.

I bought a 18”x 1/2” bosch made in germany SDS+ bit. I have gotten 6 holes full depth, with only slight wear- HUGE difference.If I could figure out a way to reliably stem a 1-2”x and i” hole black powder would FAR cheaper than sierra shots, albeit more dangerous- please spare me safety lectures, I’m aware.

I cant find a true 10mm made in Getmany bit. Thats all I need. 10mm is NOT equal to 3/8”.

It is not recomended to water cool sds bits unless you have ability to continuously bath them in fresh water. Dipping them in water when hot instantly destroys them from thermal shock.

i have spent over $1000 on sierra bits, all Im asking is if anyone knows how to import/buy 10mm bits from Germany.

 

[arizau]

Here’s the thing,

Im told this is norcal andesite <sic>? aka blue granite.. It is almost 8 mohs. The shards sound like glass/porcelain when shoveled. Sometimes the sierra bits fail in 30 seconds of use. Sometimes i can get a few holes, sometimes only 1. I baby them, rotate bits (6”, to 12, to 18, to 20) doesnt matter, they are simply not built to handle rock with this compressive strength and hardness.

I bought a 18”x 1/2” bosch made in germany SDS+ bit. I have gotten 6 holes full depth, with only slight wear- HUGE difference.If I could figure out a way to reliably stem a 1-2”x and i” hole black powder would FAR cheaper than sierra shots, albeit more dangerous- please spare me safety lectures, I’m aware.

I cant find a true 10mm made in Getmany bit. Thats all I need. 10mm is NOT equal to 3/8”.

It is not recomended to water cool sds bits unless you have ability to continuously bath them in fresh water. Dipping them in water when hot instantly destroys them from thermal shock.

i have spent over $1000 on sierra bits, all Im asking is if anyone knows how to import/buy 10mm bits from Germany.

Maybe you have already done this....You should be able to find a manufacturers catalog/website using google. Use the manufacturers contact info to find who they use as a U.S. distributor(s). The distributor(s). may stock or can special order what you need.

Good luck.

 

[Assembler]

Here’s the thing,

Im told this is norcal andesite <sic>? aka blue granite.. It is almost 8 mohs. The shards sound like glass/porcelain when shoveled. Sometimes the sierra bits fail in 30 seconds of use. Sometimes i can get a few holes, sometimes only 1. I baby them, rotate bits (6”, to 12, to 18, to 20) doesnt matter, they are simply not built to handle rock with this compressive strength and hardness.

I bought a 18”x 1/2” bosch made in germany SDS+ bit. I have gotten 6 holes full depth, with only slight wear- HUGE difference.If I could figure out a way to reliably stem a 1-2”x and i” hole black powder would FAR cheaper than sierra shots, albeit more dangerous- please spare me safety lectures, I’m aware.

I cant find a true 10mm made in Getmany bit. Thats all I need. 10mm is NOT equal to 3/8”.

It is not recomended to water cool sds bits unless you have ability to continuously bath them in fresh water. Dipping them in water when hot instantly destroys them from thermal shock.

i have spent over $1000 on sierra bits, all Im asking is if anyone knows how to import/buy 10mm bits from Germany.

If you add water when you change to a fresh cool bit you will not damage the bit. The water will cool both the rock and the bit for a short time as it boils off.
What alloy bit are you trying to find?

 

[Assembler]

Carbide tools are harder than steel and more resistant to high cutting temperatures, but they may not be wear resistant enough for granite. Diamond bits may need to be used.

 

[Mountaineer2020]

Here’s the thing,

Im told this is norcal andesite <sic>? aka blue granite.. It is almost 8 mohs. The shards sound like glass/porcelain when shoveled. Sometimes the sierra bits fail in 30 seconds of use. Sometimes i can get a few holes, sometimes only 1. I baby them, rotate bits (6”, to 12, to 18, to 20) doesnt matter, they are simply not built to handle rock with this compressive strength and hardness.

I bought a 18”x 1/2” bosch made in germany SDS+ bit. I have gotten 6 holes full depth, with only slight wear- HUGE difference.If I could figure out a way to reliably stem a 1-2”x and i” hole black powder would FAR cheaper than sierra shots, albeit more dangerous- please spare me safety lectures, I’m aware.

I cant find a true 10mm made in Getmany bit. Thats all I need. 10mm is NOT equal to 3/8”.

It is not recomended to water cool sds bits unless you have ability to continuously bath them in fresh water. Dipping them in water when hot instantly destroys them from thermal shock.

i have spent over $1000 on sierra bits, all Im asking is if anyone knows how to import/buy 10mm bits from Germany.

Ok I get the original post question now. So I came up with heller being a German brand and if my sierra bits fail I might give them a go. Here's a link to an amazon heller seller. Of course could be a misbranded knockoff but for $6 I'd give it a go. https://www.amazon.com/Heller-15628-Hammer-Bionic-SDS-plus/dp/B000VKM4JY Best of luck man. And ya I only run the bits for a 10 count on the 6" and 13 count on the longer ones dry. Plus just running through quartz and argillite not that crazy blue granite you got.

 

[russau]

Years back when I was still working I had a boss (nice guy ) that insisted on repairing our bits by removing the carbide tip and resoldering a new carbide tip on it. I never had to do this but it seems like a idea to think about. I never saw where he wanted to get the carbide tips from or how much they cost VRS. just buying a new bit or resharpening the carbide when it gets to dull................

 

[Assembler]

Years back when I was still working I had a boss (nice guy ) that insisted on repairing our bits by removing the carbide tip and resoldering a new carbide tip on it. I never had to do this but it seems like a idea to think about. I never saw where he wanted to get the carbide tips from or how much they cost VRS. just buying a new bit or resharpening the carbide when it gets to dull................

I have run into someone that hunts for used bits to either sharpen or re-silver-solider new tips on.
Sharpening can be done with out much cost.