Band saw arm weight

Yes, but although an adjustable damper might provide more control than a spring, it doesn't answer Andrew's original question - what's the optimum pressure?

A number of posts point to there being a wide range of acceptable settings that depend on variables like:

• the material being cut
• the size and shape of the stock
• number of teeth, their shape, and how sharp they are
• what the blade is made of
• blade speed
• motor power and ability of the blade to deliver it without bending or breaking
• lubrication and swarf clearance
• the goal - cutting speed versus blade life

All these effect the feed-rate, and I suggest are only worth fussing with if the saw spends most of it's time on the same job.

The saw In my workshop cuts something different every time. So I usually run it at the same setting no matter what.   It's set to suit mild-steel, and I've only changed it a couple of times, both when a lot of Aluminium had to be cut. Otherwise, I don't bother.

Dave

Edited By SillyOldDuffer on 01/05/2022 10:03:27

with so many variables i doubt that the optimum pressure is obtainable with any machine to be found in our type of workshop. mine is not even adjustable and is never a problem. i just put the job in the saw walk away and do something else.

SillyOldDuffer

As martin says the variety of jobs and materials we see make it a practical impossibility to define an optimum pressure let alone actually set the saw to give it.

Generally not so much down pressure that the blade gets upset or so little that cutting takes "forever" has to do. Plus knowing when a little hand assistance either way is needful. Certainly that was the way I used mine in the days before the Rapidor power hacksaw took over the bulk of the stock cutting work.

Whatever the designers intent the standard spring pressure adjuster is impossibly cumbersome beyond finding and holding a general purpose position that can be used for "most" jobs. There were a few things that I had to accept that mine could not be made to safely cut. Such as thin wall tube.

In contrast hydraulic systems are easily adjustable. So, given appropriate calibration on the adjuster valve, it is little trouble to change settings when changing materials. Obviously it takes a bit of experimentation and note taking to evolve a list that suits your saw and your work. But once its done changing the setting is no harder than changing feed-rate on a QC gearbox equipped lathe. Just like feed rate, choosing from a couple or three settings will do well enough for most jobs but sometimes you need to be more optimal to avoid stripping the teeth from the blade or ending up with a wandering cut.

Optimum is an impossible dream for us but usefully better than an "it will have to do" general purpose setting for jobs when that isn't really appropriate seems quite realistic.

Its usually fairly obvious when the saw is seriously struggling making a swift adjustment desirable.

According to the professionals getting close to an optimum blade pressure / downfeed rate vastly increases blade life.

Certainly when I got mine I ran through several blades quite quickly due to a combination of the down pressure being way too high and the impossibility of correctly adjusting the blade guides correctly. But mine was an early version, got maybe 45 years ago, so the manufacturing standards and quality of blades in the box were much poorer than todays offerings.

Clive

Not the actual quote unfortunately, Michael, but I do have a record of posting this (in another guise) to the forum back in 2014:

"According to a PM conversation I had with the web-maintenance lady (Katie?) some time ago, .............Apparently, the editor can be configured so that smileys can only be added via the drop-down (thus solving the problem of, for example, quote followed by parenthesis). However users in some other forums here are deathly afraid of mice (presumably they leap up on chairs when they see one). To accommodate them, the editor is configured to insert smileys the old-fashioned way (via keyboard characters) in addition the the drop-down."

(Perhaps what I'm remembering is not an actual thread but an offline conversation).

Edited By Peter Greene 🇨🇦 on 05/05/2022 01:57:48