Anybody know where bits or arbors to fit a Skil 732 Roto-hammer
can be found? Bought it with a few bits for $50, now that it
seems to work it'd be nice to add one or two newer bits and
maybe a chuck arbor.

The drive tang is 9/16" hex, the tool retainer has a 3/4" hex.
Far as I can tell very, very little is available in that size.
An ordinary half inch chuck would probably suffice for the little
work I'd do.


Initially I was rather surprised at how much it vibrates. On taking
it apart it's understandable: The striker is only about 25% of the
reciprocating mass, none of which is counterbalanced. Are modern
designs any better?

Thanks for reading, and any guidance.

bob prohaska

On Sun, 17 Apr 2016 03:26:16 -0000 (UTC), bob prohaska
wrote:

Anybody know where bits or arbors to fit a Skil 732 Roto-hammer
can be found? Bought it with a few bits for $50, now that it
seems to work it'd be nice to add one or two newer bits and
maybe a chuck arbor.

The drive tang is 9/16" hex,

Doublecheck that, Bob. I believe that you'll find that it is a 13mm
hex drive, not 14.28mm / 9/16".


the tool retainer has a 3/4" hex.
Far as I can tell very, very little is available in that size.
An ordinary half inch chuck would probably suffice for the little
work I'd do.

This is timely. I just ordered, received, and used a 12mm x 280mm hex
shanked (13mm) masonry bit last week. Gunner had given me a bitless
driver (Makita MA-2714) last October and I finally found a $12 import
bit thru eBay. http://tinyurl.com/zvjum5x Uxcell and Amico have many
sizes. Like you, I found -squat- in Home Depot, Lowes, or Medford
Tool, or any local auto parts stores.


Initially I was rather surprised at how much it vibrates. On taking
it apart it's understandable: The striker is only about 25% of the
reciprocating mass, none of which is counterbalanced. Are modern
designs any better?

Who can afford one to see? Then again, they're designed to be used
against a bit, not operated in space, so it may not shake as much when
it's in use. Hammer drills do vibrate a lot, though. It's their
nature. Anti-vibration gloves were designed AFTER hammer drills.

--
If you want to make your dreams come true,
the first thing you have to do is wake up!
--anon

On Sun, 17 Apr 2016 03:26:16 -0000 (UTC), bob prohaska
wrote:

Anybody know where bits or arbors to fit a Skil 732 Roto-hammer
can be found? Bought it with a few bits for $50, now that it
seems to work it'd be nice to add one or two newer bits and
maybe a chuck arbor.

The drive tang is 9/16" hex, the tool retainer has a 3/4" hex.
Far as I can tell very, very little is available in that size.
An ordinary half inch chuck would probably suffice for the little
work I'd do.


Initially I was rather surprised at how much it vibrates. On taking
it apart it's understandable: The striker is only about 25% of the
reciprocating mass, none of which is counterbalanced. Are modern
designs any better?

Thanks for reading, and any guidance.

bob prohaska

If you have a lathe a better option may be to buy an A taper adapter
for your tool.
http://www.bamanufacturing.com/page_34.htm

Then you can turn a taper on the shank of any old bit to fit the
adapter. I also have a rotary hammer that takes an unusual shank, an
old AEG, but it came with an adapter so I grab used bits when I see
them cheap. I don't remember off the top of my head what the angle of
the taper is, but it's not awfully fussy and easy to turn with the
lathe compound.

--
Ned Simmons

Larry Jaques wrote:
On Sun, 17 Apr 2016 03:26:16 -0000 (UTC), bob prohaska
wrote:

Anybody know where bits or arbors to fit a Skil 732 Roto-hammer
can be found? Bought it with a few bits for $50, now that it
seems to work it'd be nice to add one or two newer bits and
maybe a chuck arbor.

The drive tang is 9/16" hex,

Doublecheck that, Bob. I believe that you'll find that it is a 13mm
hex drive, not 14.28mm / 9/16".

Just did. .562 inch across the flats and 2.25 inch long on an original
Skil bit.



Initially I was rather surprised at how much it vibrates. On taking
it apart it's understandable: The striker is only about 25% of the
reciprocating mass, none of which is counterbalanced. Are modern
designs any better?

Who can afford one to see? Then again, they're designed to be used
against a bit, not operated in space, so it may not shake as much when
it's in use. Hammer drills do vibrate a lot, though. It's their
nature. Anti-vibration gloves were designed AFTER hammer drills.


I bought this tool mostly to see what I could learn from it. Lesson
number one is that vibration is a signficant issue, not only for
comfort but also for tool control.

Lesson number two is perhaps more surprising: Searches for bits that
fit the tool are incredibly laborious because the shank size gets
confused with the bit size. If the shank was SDS or something equally
arbitrary it'd be much easier.

Thanks for writing, I'll just have to keep looking.

bob prohaska

Ned Simmons wrote:

If you have a lathe a better option may be to buy an A taper adapter
for your tool.
http://www.bamanufacturing.com/page_34.htm

Then you can turn a taper on the shank of any old bit to fit the
adapter. I also have a rotary hammer that takes an unusual shank, an
old AEG, but it came with an adapter so I grab used bits when I see
them cheap. I don't remember off the top of my head what the angle of
the taper is, but it's not awfully fussy and easy to turn with the
lathe compound.


I'd be really surprised if the shank of a hammer bit could be turned
in a lathe without annealing and re-hardening.

There do seem to exist hex-shank to SDS adapters:

http://www.amazon.com/200mm-Silverli.../dp/B000LFW3Q8

Maybe I should look more closely at those. I really wanted to get away
from proprietary toolholders. B&A sells very little in 9/16" hex drive
apart from adapters to their own bits. It's possible to buy SDS bits
at my local hardware store.

Thanks for writing,

bob prohaska

On Saturday, April 16, 2016 at 8:29:40 PM UTC-7, bob prohaska wrote:
Anybody know where bits or arbors to fit a Skil 732 Roto-hammer
can be found?

Maybe it'd be easier to adapt to other bit sizes

http://www.bamanufacturing.com/pat728.html

On Mon, 18 Apr 2016 03:41:23 -0000 (UTC), bob prohaska
wrote:

Ned Simmons wrote:

If you have a lathe a better option may be to buy an A taper adapter
for your tool.
http://www.bamanufacturing.com/page_34.htm

Then you can turn a taper on the shank of any old bit to fit the
adapter. I also have a rotary hammer that takes an unusual shank, an
old AEG, but it came with an adapter so I grab used bits when I see
them cheap. I don't remember off the top of my head what the angle of
the taper is, but it's not awfully fussy and easy to turn with the
lathe compound.


I'd be really surprised if the shank of a hammer bit could be turned
in a lathe without annealing and re-hardening.


I've never tried tapering an SDS or similar shank, but I've turned a
taper on many straight-shank bits, including a couple large core bits.
None were hard enough to be a problem. Factory made A taper shanks are
not harder than perhaps Rc30.


--
Ned Simmons

On Mon, 18 Apr 2016 03:41:23 -0000 (UTC), bob prohaska
wrote:

Ned Simmons wrote:

If you have a lathe a better option may be to buy an A taper adapter
for your tool.
http://www.bamanufacturing.com/page_34.htm

Then you can turn a taper on the shank of any old bit to fit the
adapter. I also have a rotary hammer that takes an unusual shank, an
old AEG, but it came with an adapter so I grab used bits when I see
them cheap. I don't remember off the top of my head what the angle of
the taper is, but it's not awfully fussy and easy to turn with the
lathe compound.


I'd be really surprised if the shank of a hammer bit could be turned
in a lathe without annealing and re-hardening.

There do seem to exist hex-shank to SDS adapters:

http://www.amazon.com/200mm-Silverli.../dp/B000LFW3Q8

Maybe I should look more closely at those. I really wanted to get away
from proprietary toolholders. B&A sells very little in 9/16" hex drive
apart from adapters to their own bits. It's possible to buy SDS bits
at my local hardware store.

There ya go. That's the ticket.

--
If you want to make your dreams come true,
the first thing you have to do is wake up!
--anon

whit3rd wrote:
On Saturday, April 16, 2016 at 8:29:40 PM UTC-7, bob prohaska wrote:
Anybody know where bits or arbors to fit a Skil 732 Roto-hammer
can be found?

Maybe it'd be easier to adapt to other bit sizes

http://www.bamanufacturing.com/pat728.html

At least in my neck of the woods, SDS seems to be the
most widely-stocked hammer drill shank. I was hoping
there might be a non-proprietary alternative, but that's
simply not the case.

The problem now is to find an adapter that fits a Skil
732 rotohammer and takes an SDS tool. This might work:
http://www.amazon.com/200mm-Silverli.../dp/B000LFW3Q8
but the ad seems a bit "off". The review is nonsense, and somewhere in
the fine print it says the item ships from the UK.

It seems likely that "native" bits with a 9/16" hex shank will couple
better to the hammer, so I'll keep looking until there's some urgency.

Thanks to all for reading and replying!

bob prohaska