Slitting saws

[firebird]

Hi

Iv'e only used slitting saws a couple of times but have ruined them quite quickly. Is there a trick to using them? What speed do you use? Are they a use them once and throw them away tool? are there better quality ones that dont fail so quick?

Any help and advice would be very useful.

Cheers

 

[Powder keg]

I usually run them pretty slow. Remember that with HSS "Blue is Bad" If the chips are changing color your cutter will go Bye Bye. Alwayse use some kind of cutting fluid or a mister on it. I started using a mister on my mill and will never go back.

Hope this helps, Wes

 

[firebird]

Hi Wes

What is a mister?

Cheers

 

[1Kenny]

Mister is spraying on coolent or oil.

Kenny

 

[Powder keg]

Here is a link to one. http://www.use-enco.com/CGI/INSRIT?PMAKA=505-1984&PMPXNO=951137&PARTPG=INLMK3 mister

 

[cfellows]

Firebird,

I don't use coolant or misters (yet). I usually try to keep the rpm of slitting saws under 200 rpm and use a slow feed, at least for steel. For brass or aluminum, higher rpm's and faster feeds are probably OK. Stop your mill now and again and touch the blade. If it's too hot to touch, your rpms are probably too high. More aggressive cuts may be possible, but I haven't destroyed one yet.

Chuck

 

[DICKEYBIRD]

Looking at your saws, I'd say they were turning way too fast. The surface speed is way up there with the large diameter. HSS saws are very fragile (in my world anyway) and have to be turned very slowly and lubed liberally, especially in steel. Looks like you were cutting steel?

I bought a little carbide tipped saw blade at the local Home Depot and made an arbor for it. http://www.homemodelenginemachinist.com/index.php?topic=542.0

I love it! It does MUCH better than HSS in aluminum and steel. Still gotta watch the speed & feed in steel but you can cut the crap out of aluminum with it.

 

[Mcgyver]

those are burnt out - what speed are you running at? remember, rpm=CS*4/dia". CS for HSS on steel is say 80 feet per minute, so the larger dia one should be run at say 120m rpm. coolant deals with heat, but its not heat the wrecks the tool its temperature - regardless of how well you can remove heat if you exceed the cutting speed the temp at the edge of the tool will become too hot and the tool burns out. a pump spray bottle is a good way to apply coolant, which btw also provides lubrication not just cooling....slow it waaay down and squirt some coolant and those blades will last years.

 

[Cedge]

Dickeybird
Mounted the carbide blade on an arbor today. It took about 2 seconds to declare that rig a keeper. It's amazing with aluminum, although I've not tried it out with brass or steel yet. Hard to fault a 6 dollar tool that performs so well.

Steve
Who has also burned up a few slitters before slowing things down

 

[firebird]

Hi

Thanks for all the replies. Yes I was running it at too high a speed and with no lub or coolant. Well you live and learn. I like that TCT blade. Any ideas where I can get one in the UK.

Cheers

 

[DICKEYBIRD]

F/B you should be able to get one at any U.K equivalent to our Lowe's or Home Depot (home improvement big box stores.) It fits a cordless trim saw...it's like a small circular saw.

I picked up an even bigger one last week: 5 1/4" 'cuz it was on sale at Harbor Freight. I haven't made an arbor for it yet but it should do as well and make really deep cuts.

I'm building a disc sander in the shop right now and am cutting the parts from 1/2" aluminum plate. I'm using my woodworking chop saw and table saw, both fitted with 10", 80 tooth carbide blades. I'm simply amazed at how accurate and nicely finished the cuts are. Ear protection and safety glasses are a must because the chips fly around like a snowstorm. I have no idea what the SFM is but man does it shift some metal!

 

[Powder keg]

DICKEYBIRD, You might be interested in this. Make sure you watch part two also:O) [ame=http://www.youtube.com/watch?v=BYllaxuzMk0]http://www.youtube.com/watch?v=BYllaxuzMk0[/ame]

 

[Lew Hartswick]

That sander is realy great. Thanks.
...lew...

 

[BobWarfield]

A few thoughts:

First, using the small carbide blades as slitting saws is an awesome idea. I'll be on the lookout at my local hardware store. FWIW, I have purchased a bunch of slitting saws off eBay that were brand new and cheap. I don't think they're very popular cutters, at least nowhere as popular as end mills.

Second, if you like those carbide blades, look into a DeWalt Multicutter as a replacement for the bandsaw when cutting stock. This has been one of my favorite tools since getting it. The bandsaw has languished in the corner because the DeWalt is so much faster and leaves a nicer cut. Here is what it looks like:

Note that it runs more slowly than a regular saw would, so the blade lasts longer.

Cheers,

BW

PS Love the belt grinder. I'm working on one just like it. They're not too hard to build from scratch. I want a big disc too.

 

[Loose nut]

Besides using the right RPM'S as stated above it is important to use the right travel speed Depth of cut per tooth times number of teeth for the given material, over loading a cutter will do it no good. Machinery's handbook or other books have tables with all this info plus the feet per minute for each material to calculate the proper RPM'S.