Blade Advice - Cutting Brass

[Harbo]

I have a couple of Hegner Blades multipacks - one looks a lot older than the other.
The newer one marked Hegner UK has blades prefixed WB which from their web site say are for cutting wood and soft metals.
The older one just marked Hegner has a collection for "For wood, plastics, soft metals (aluminum, soft brass) marked Nr 1, 5 & 9 and another set for steel and other non ferrous metals marked similarly.
Hegner also sell a range of piercing blades too.

I am about to cut out some brass wheels (spokes) and brass frames - I am making a clock so which is the best one to use?
I only have a few of each and will need to buy some more?

Thanks for any advice.

Rod

 

[Blister]

I cant answer you question but maybe contact Hegner direct

http://www.hegner.co.uk/

or ask Mike from :- http://www.mikesworkshop.com/

He may have an opinion for you :wink:

 

[Harbo]

I opted for the metal ones in the end and ordered some from Mike.

Doing a bit of research, the metal types have much more TPI than the wooden types.
What puzzled me initially was how you could cut brass with the wooden ones?

A No.5 wood type has typically 15/17 TPI whereas a metal cutting No.5 has 33/36.

Rod

 

[donwatson]

Rod,
I will try and explain what I know about saw blades.
You should never use a coarse pitch blade to cut thin material. This applies whether wood or metal.
If you imagine the cutting edge of the blade (the teeth), on the carpenters saw, for wood, probably has the point of each tooth 1/2" apart.
Now if you want to cut through a piece of timber 4" square you will have 8 teeth all cutting at the same time and all is ok.
Now if you want to cut a piece of 4" wide by 1/8" thick you automatically turn it on its side and saw across the 4" because you know what will happen if you try to cut down the 1/8", the wood keeps dropping into the teeth.
Metal saws have the same problem that is why their teeth as closer together, to cut finer material.
The worst examples I saw of this was in the Toolroom when I would set up a 12 TPI bandsaw blade and cut some 2" square brass.
10 minutes later some Fitter would come in, switch on the saw (usually without adjusting the fence) and try and cut a piece of 1/16" material. The result was chaos and a ruined blade as the blade tried to cut a full tooth wide which ripped off teeth and sent them everywhere.These teeth were hard to remove from eyes.
What I am trying to say is you should try and have at least 3 teeth in contact with the material you are cutting.

take care
Don W

 

[puzzler]

Hi Rod
It's advisable to slow speed and feed rate.
Thin metals will likely burr out on the bottom edges to prevent your table getting scratched
support metal on piece of ply or fit an auxilliary table
Regards Puzzler