Stainless Holesaw?

[Windy Miller]

Anybody used these before?http://www.starrett.co.uk/shop/holesaws/tct_stainless_steel_hole_saw/

Are they as good as the advert says? Anything I should be aware of?

I have to drill a 50 mm hole in the counter of a stainless salad bar in a works cafe, so if any lube is required for these hole saws, I assume it should be 'food safe'?

I've done hardly anything in SS before, so any advice would be very welcome!

 

[Tinbasherdan]

Anybody used these before?http://www.starrett.co.uk/shop/holesaws/tct_stainless_steel_hole_saw/

Are they as good as the advert says? Anything I should be aware of?

I have to drill a 50 mm hole in the counter of a stainless salad bar in a works cafe, so if any lube is required for these hole saws, I assume it should be 'food safe'?

I've done hardly anything in SS before, so any advice would be very welcome!

Any decent hole saw will boss it, and if it's just a counter top it's not going to be the thickest material going. As for lube, I always used trefolex and just wiped it clean after

 

[piman]

Hello Windy Miller,

I use the standard HSS hole saws and I drill a lot of holes in stainless, normally in a drill press but occasionally free hand. Try and get the drill as slow as possible and use a lot of pressure. It can be done without lubrication but it does help, on the other hand I don't expect a bar top will be very thick.

Alec

 

[hotrodder]

As said they're not needed, regular HSS hole saws cope fine with stainless just like regular HSS drills do. Think of them as the holesaw equivilant of a dry cutting TCT chopsaw... don't need coolant/lube, want/cope with far higher rpm than HSS, relatively fragile and more expensive but allow higher cutting speeds which, as time = money, can cancel the extra ££ they cost over their lifetime

A 50mm HSS or HSS-Co holesaw into stainless ideally wants ~ 65 - 85rpm which obviously ain't gonna happen with most hand held drills, as said as low as you can get rpm wise and lean on it

Assuming the top isn't cladding over wood/mdf so the hole is just through sheet then Q-max hole punches are usually faster and always produce more accurate* holes that are virtually burr free. More expensive than a regular HSS holesaw but cheaper than a TCT one. Offical capacity of Q-max cutters is 16swg/1.6mm with stainless IIRC but mine have been abused on thicker stuff without killing 'em

* With thin sheet holesaws are even worse as the material isn't thick enough i.e. they're more prone to wandering as the pilot drill doesn't have enough support. Replacing the pilot drill with a solid mandrel helps, if/when it's possible knocking a hole through some wood and using that as a guide works even better

 

[ford34/2]

last one I did, I predrilled some 3/4" ply with the hole saw first, managed to clamp that to the top to guarantee a guide and the hole cutter not to wander off and the pilot hole to stay where I wanted it to, bit lub, no problems and straight through, + free fish and chips for dinner. Dont you just love Bimbis fish and chips.

Stan

 

[Kram]

Carbide will have wider teeth, more likely to move about. HSS teeth are also set and will cut oversize... 44mm will give a ~48mm hole. Cobalt HSS is only a few pence more. Food safe - it really doesnt matter anything you use, as its going to be cleaned after.

http://www.ebay.co.uk/itm/Ruko-Hole-Saw-44mm-1-3-4-HSS-Bi-Metal-Co-8/260551458909

 

[brightspark]

ive just drilled 9x 75mm holes in 1/16th stainless sheet on a bench drill with cutting compund using a starret hss cutter. its still-cuts but overheats now

 

[langy]

As the others have said it a good quality holesaw will do that job easily, I regularly use starret or morse to cut 1/4" stainless, personally I wouldn't use any holesaw without a decent compound.

 

[Windy Miller]

Thanks very much for all your comments and advice guys.

As far as I know, the counter top is about 3 mm thick. I'm a little nervous about doing this, as it's the first 'professional/commercial' job that I have taken on, and I don't want to screw it up! I work full time as a contractor in the IT department of this company, and I was approached by a bloke in the Building Maintenance department as he knows I mess about with metal in my spare time! They have a really good team of chippies, painters, plasterers, sparkies, plumbers etc, but nobody who does any metalwork, and they all seem to be a bit scared of stainless steel!

You guys that do it all the time are probably thinking what's all the fuss about, but it's been donkeys years since I did any site work, and I'm not geared up for it anymore. In a previous life I was a mobile mechanic and I had a van load of kit at my disposal, but it's all in the garage now, so I'm worried that I'll not bring enough gear to deal with these unexpected things that always seem to happen! He has offered me loads of money to do this job, and there will be more work if it all goes well, so I am keen to do it right.

Very good advice about the replacing the pilot drill with a plain mandrel. I'll have a look and see what is under the counter top and maybe wedge a wooden block in with a scissor jack.

I'll get myself a decent C0-HSS holesaw (any suggestions which one?), and also one of those tct jobbies just in case as I think that my hand drill will be too fast for the normal holesaw. I REALLY don't want to use the plasma cutter for this, so I'm hoping that the other tools will do it OK. Shame the material is too thick for a Q-Max cutter - that looks like the best suggestion!

It's a well paying job, so if I end up buying kit that I didn't really need it's no big deal. It'll always come in handy some other time!

Thanks again for your help!

 

[Robotstar5]

Don't forget the de-burring tool, does a much better job than a file.

 

[awemawson]

The secret with cutting stainless steels is not to let the cutter rub. Stainless will work harden very easily if a cutter rubs rather than cuts, so as has been said, slow speed and significant pressure.

 

[daleyd]

Starrett are one of the better makes, I've got a few of those and though they've not been used much on stainless they've done loads of holes in electrical panels etc and still going strong.

Edit - not the ones you linked to, just standard HSS ones...

 

[ford34/2]

Starrett have a large factory just near us in Jedburgh, you can order online and have it delivered or arrange to collect from a local Starrett dealer, dont seem to have any factory shop or collection facilities in Jedburgh. Shame you could have called in the Otterburn Mill, not for clothes -the line shafts, drives, pulleys etc, and then onto the Jedburgh Starrett shop, canny day out
Stan
http://www.starrett.co.uk/contact/

 

[brightspark]

buy a starret arbour and starret holesaw. cheapo pilot drills and arbours run off and snap its a 2minute job if u have a recargeable drill on slow speed with cutting compound or oil at the push-

 

[Windy Miller]

buy a starret arbour and starret holesaw. cheapo pilot drills and arbours run off and snap its a 2minute job if u have a recargeable drill on slow speed with cutting compound or oil at the push-

I have a Starret arbour and the bi metal hole saw is on order. I have also ordered a tct hole saw just in case the drill is too fast. Tomorrow I'll dig out a plain bar to replace the drill bit once the pilot is through. I also have a choice of cutting oils to try, so hopefully it'll be plain sailing!

Thanks again for all the advice guys!

 

[Paul.]

You'll need a bit of 1/4" dia bar for the arbour, I use stubbs silver steel in mine its less likely to bend if you have a snag with the cutter, a bent arbour centre can very quickly make an expensive mess of a job,

 

[brightspark]

i made a silver steel one- hardened and temperted it stops it w-andering and ruining your job -

 

[Windy Miller]

An update:

I did the stainless drilling job today, and as you all said, it was very straightforward.

In the end it turned out to be two 50mm holes, and one 30mm. I had bought one of those Starrett tct cutters for the bigger holes, and I used an ordinary Starrett hole saw for the smaller one. Luckily I had that one with me, as I was only expecting to drill one bigger hole! That was the point I was making about not being geared up for site work anymore - its was only luck that I was running late so I just grabbed the whole box of holesaws instead of taking the time to find the one I thought I would need!

Anyhow following the advice given here, I had made up silver steel guide rods to replace the pilot drills, and I used plenty of cutting oil. Each hole tool no more than a couple of minutes, and after a quick whizz round with a deburring tool that was that - job done! So big thanks for all the sound advice.

What I did learn however was that my old 110v Bosch SDS drill is not really man enough for the job. Fair enough it has more or less infinite speed control, but at slow speeds there is absolutely no torque to speak of, so I ended up running it faster than I would have liked. It did the job ok, but I was glad that the material was only a couple of mm thick. Any thicker and I think the holesaws may have ended up getting knackered.

So it looks like I'll be in the market for another drill soon. Any suggestions? I'd love a rotabroach, but I can't really justify the expense at the moment as I wouldn't use it often enough. What I'm looking for is a slow speed mains or battery drill that has enough torque to drive a 2 or 3 inch hole saw. What would fit the bill?

 

[brightspark]

a 700watt makita 2 speed geared drill not just the electronic speed- controlled one-ore any decent make one geared