SDS & hole saws

[Selfmade]

Hi


I know this topic has already been covered, but I think my questions are a bit more specific. Anyway, if you think they've already been covered, feel free to ignore!


I bought a Makita HR2450 SDS drill the other day. Up until now I have relied solely on my trusty DeWalt 18V cordless combo drill, which seems to be able to do almost anything. Almost. It cannot drill granite (obviously) or large holes in high density concrete, and it struggles with large hole saws (unsurprisingly).


So I chose an SDS drill with a "mechanical safety clutch", as I thought this was what was needed for safe use of large hole saws, and would of course be well suited to granite and concrete. But on reading the instruction it says: "Hole saws cannot be used… They tend to pinch or catch… This will cause the torque limiter to actuate too frequently".


So my questions are:


a) Is their statement about hole saws likely to apply to hole-sawing wood, or just masonry/stone/metals (I never intended to attempt to hole-saw these).


b) In your experience how likely is it that I will find the drill really is incapable of hole-sawing wood, or is damaged by this, and how likely is it that they are just covering their donkeys? I won't hold you responsible if you say it's fine and then I wreck the drill!


I know some of you will be thinking I have the answer in black and white and should just follow the instructions, but I can't justify the cost of two drills (an SDS and a core drill) for two things I don't do that often, nor do I have the space to store them. It would seem ridiculous to keep using my combi for hole sawing when I have this beast of an SDS in my tool kit. Any thoughts from your own experience/knowledge?


Anyway sorry for a long post, thanks for reading to the end!


Sam

 

[Guest111]

Ouch, didnt he pilot it?

the pilot bit went through but then became detached and the cutter just shot along the timber

 

[shanky887614]

the pilot bit went through but then became detached and the cutter just shot along the timber

Bad luck that

 

[PEG]

The problem with the smaller drills with clutches is they are there to protect the operator for the occasional bind-up,whereas the purpose made core-drills have a clutch which is designed to operate as many times as necessary. The former can be used but set-up and technique will determine life expectancy (the drill,of course).Anyone want a comedy clutchless drill monologue?....anywho...there's me pal,on his barn roof,drilling a 1" hole in a crossing timber purlin,stood on tins,drilling downwards with a homemade 24" auger bit in a 1960's Ally Victor drill,auger jams,side handle hooks his boiler suit,and he goes round and round and round,probably 7 or 8 times before lead parts at top of bit...a HSE video classic :cheesy:

 

[Guest111]

The problem with the smaller drills with clutches is they are there to protect the operator for the occasional bind-up,whereas the purpose made core-drills have a clutch which is designed to operate as many times as necessary. The former can be used but set-up and technique will determine life expectancy (the drill,of course).Anyone want a comedy clutchless drill monologue?....anywho...there's me pal,on his barn roof,drilling a 1" hole in a crossing timber purlin,stood on tins,drilling downwards with a homemade 24" auger bit in a 1960's Ally Victor drill,auger jams,side handle hooks his boiler suit,and he goes round and round and round,probably 7 or 8 times before lead parts at top of bit...a HSE video classic :cheesy:

Remember those great big Hitachi drills,with the handle on the back? They were about 1100 watts I think,no clutch either well I had one and a mate wanted a 50 mm hole in the concrete for a rotary clothes line,I said I'd do it but he wanted to,well it jammed and spun him around it was quite funny at the time as he was about 16 stone and couldn't handle it yet there was I about 9 stone at the time drilling with no problems.It's definately about technique,slow and steady with not too much pressure,and a firm grip on the machine,plus ALWAYS use a side handle.

 

[Selfmade]

if you don't want to invest/store drill specifically for large cores, you can always rent on the occasion you need one and bill to job. they measure wear on core tip and charge accordingly.

Good suggestion, thanks! This may well be worth doing for jobs needing a lot of holes sawing. Maybe not so much for one or two, given the extra time spent in traffic jams at the beginning and end of the day!

also holesaws are different to cores

So hole saws are shallow and for wood, plaster etc, and cores are deep and for masonry/concrete/stone? Have I picked this up right? If so it is hole saws I am using, not cores.

 

[Geordie Spark]

Good suggestion, thanks! This may well be worth doing for jobs needing a lot of holes sawing. Maybe not so much for one or two, given the extra time spent in traffic jams at the beginning and end of the day!



So hole saws are shallow and for wood, plaster etc, and cores are deep and for masonry/concrete/stone? Have I picked this up right? If so it is hole saws I am using, not cores.

Hole saws have teeth on them like a saw.

Core drills do not.

Core drills will make holes in brick & concrete. Try doing that with a holesaw and see how far you get and core drills are not very happy about drilling holes in wood either!

Why not use Google to find some pictures of each???

 

[Selfmade]

Just seen your question ,the last one lasted about 2 years , continuously being used for chasing on cement faced walls and engineering bricks etc , so full of brick dust all the time , I have had other drills and knocked them out in no time , the Bosch takes some stick all right or I wouldn't be using them , Its a pity some of the SDS chiselling bits don't last long though ,

Eww, I was hoping mine would last 15 years like Rockingit's Bosch! Makes hiring seem a whole (no pun intended) lot more economic! As for bits, I always buy cheap ones as I find they are all practically disposable, so why waste money on expensive branded ones...

 

[Selfmade]

Without reading all this thread....
I have a De Walt 18v SDS that I use to drill 2" holes in stainless enclosures on a regular basis.

It's more technique then power. You need very slow speed moderate pressure, lots of cutting fluid and a good variable pitch hole saw like Starret.

As you say in your next post not totally relevant but interesting none the less, and probably not just applicable to metals.

It's heat that kills the saws so keep it slow and lubricated....ooo matron.

Think this bit should have been on a (the?) thread by a certain young lady!

 

[Selfmade]

I do a lot around 60 - 70mm (I forget the precise sizes I have!) in plasterboard for downlights, though it beats me why people like the things, but hey can't complain! My combi is fine with these, but it does gum it up with plaster dust which I have to clean out.

Stainless holesaws do sound nice but I bet they cost a bit!

 

[Geordie Spark]

As you say in your next post not totally relevant but interesting none the less, and probably not just applicable to metals.



Think this bit should have been on a (the?) thread by a certain young lady impersonator!

Corrected that for you.

 

[Selfmade]

I hired a KANGA when I was a nipper. Girlfriend wanted a catflap through the main wall of the house so off I go, snags, nearly broke my wrist. Seriously. It was really really sore for weeks.

Ouch!

So I don't mind the slippy clutches now!

Yes, definitely better with the clutch I think!

 

[Selfmade]

the pilot bit went through but then became detached and the cutter just shot along the timber

When I wrecked my Homebase own brand (feel free to laugh), the pilot jumped right out of the hole and the cutter shot along the timber, but missed my forehead thankfully!

 

[Geordie Spark]

I do a lot around 60 - 70mm (I forget the precise sizes I have!) in plasterboard for downlights, though it beats me why people like the things, but hey can't complain! My combi is fine with these, but it does gum it up with plaster dust which I have to clean out.

Stainless holesaws do sound nice but I bet they cost a bit!

Use a plastic carrier bag to stop this.

Take one cheapo ASDA type carrier bag.

Poke a hole in one of the bottom corners big enough to pass the drill chuck through

Place the drill in the bag with the chuck sticking through the hole and allow the bag to hang loose around the body of the drill to prevent possible overheating.

Two advantages of this method are; 1) It stops the draught from the machines fan blowing ducking fust all over the place and 2) it prevents a lot of ducking fust from getting sucked into the drill.

Try it and see.

 

[Selfmade]

The problem with the smaller drills with clutches is they are there to protect the operator for the occasional bind-up,whereas the purpose made core-drills have a clutch which is designed to operate as many times as necessary. The former can be used but set-up and technique will determine life expectancy (the drill,of course).Anyone want a comedy clutchless drill monologue?....anywho...there's me pal,on his barn roof,drilling a 1" hole in a crossing timber purlin,stood on tins,drilling downwards with a homemade 24" auger bit in a 1960's Ally Victor drill,auger jams,side handle hooks his boiler suit,and he goes round and round and round,probably 7 or 8 times before lead parts at top of bit...a HSE video classic :cheesy:

Thinking about this, I can't see it being a big problem if the clutch operates as frequently as I have stalled my poor long suffering combi when using a hole saw, unless the clutch is extremely flimsy. So I'm going to try minimal feed pressure (as has been suggested) and making sure that I cut at exactly 90° to the timber, as the starting point for my technique.

Anyway definitely better to risk the drill's life expectancy than my own, so better with a clutch than without!

Funny how an accident can be so comic! And a home made auger bit? Rather him than me!

 

[Selfmade]

Remember those great big Hitachi drills,with the handle on the back? They were about 1100 watts I think,no clutch either well I had one and a mate wanted a 50 mm hole in the concrete for a rotary clothes line,I said I'd do it but he wanted to,well it jammed and spun him around it was quite funny at the time as he was about 16 stone and couldn't handle it yet there was I about 9 stone at the time drilling with no problems.It's definately about technique,slow and steady with not too much pressure,and a firm grip on the machine,plus ALWAYS use a side handle.

Lol! I'd have been worried about being in his path when centrifugal force took over!