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Hacksaw Frame Guide: Tension, Blade Counts and Frame Material
A hacksaw frame is a tensioning device first and a handle second. The blade is what cuts, but the frame decides whether the blade runs true: a frame that will not hold tension cuts a curved kerf, and a frame with a fixed angle makes every cut in a pipe or a cable tray harder than it needs to be. This guide covers the aluminium alloy frames in this range, how the blade counts are made up, and the technique that keeps a hacksaw cutting straight in steel.
What a frame has to do
- Hold tension. The blade must be tight enough to ring. A slack blade buckles on the push stroke and cuts a wandering kerf.
- Adjust the angle. Frames that allow the blade to be set at 45 degrees let you cut flush against a surface, which a fixed frame cannot do.
- Fit the blade length you own. A 300 mm blade in the wrong frame will not tension. Match the frame to the blades you keep.
- Stay rigid. Aluminium alloy frames are light, which matters at arm’s length, but they must not flex under load. A frame that bends sideways takes the blade with it.
- Reach into the work. The depth of the frame throat decides how wide a section you can cut before the frame fouls it.
Frames, blades and the counts in this range
| Option | Frame | Blades supplied | Where it suits | Price |
|---|---|---|---|---|
| Frame only | Aluminium alloy, adjustable | None | Replacing a frame with blades already in stock | $8.99 |
| Frame with 2 blades | Aluminium alloy, double sided blade fitted | 2 | Light use, occasional cutting | $9.39 |
| Frame with 10 blades | Aluminium alloy, double sided blade fitted | 10 | General workshop stock | $10.70 |
| Frame with 6 blades | Aluminium alloy, double sided blade fitted | 6 | Trade bag, mixed materials | $11.94 |
| Frame with 10 and 6 blades | Aluminium alloy, double sided blade fitted | 16 | Site kit with spares for both materials | $13.54 |
Choosing the frame and blade combination
The practical kit is a frame plus two blade types: a fine tooth blade for steel and conduit, and a coarser blade for aluminium, plastic and wood. A double sided blade covers both on one strip, which is why it is the blade fitted to the frames here. Where a frame is bought with blades, the counts are set up to match the way people use them: two blades for a household, six for a trade bag, ten for a workshop shelf and sixteen for a site kit that has to cover both materials without a return trip. If you already keep blades, buy the frame on its own and check the blade length and pin spacing before you order, because those two dimensions decide whether a blade will tension.
The hacksaw frames in this guide
Using a hacksaw so the blade lasts
- Tension, then check. Pluck the blade. If it does not ring, it is slack, and a slack blade breaks at the pin holes rather than wearing out.
- Use the full stroke. Short strokes wear the middle teeth and leave the blade cutting badly at both ends.
- Light pressure, steady rhythm. Hacksaw blades cut on the push stroke. Pressing harder heats the blade and takes the temper out of the teeth.
- Angle the frame for the work. On pipe and box section, set the blade at an angle, start on a flat face, and rotate the work rather than steering the saw round the curve.
- Three teeth in the cut. Keep at least three teeth in contact with the material. Too few and the teeth strip, which is why thin sheet needs a fine blade.
- Change the blade, not the technique, when cutting slows. A dull blade needs pressure, and pressure is what bends frames and snaps blades.
Faults and care
- Blade snaps at the pin hole. Always a slack blade, or a frame that has been overtightened in the past and distorted its ends.
- Kerf wanders. Uneven pressure, or a blade whose set has been worn flat by cutting through a hardened surface.
- Frame flexing. Light alloy frames bend when they are used past their section limit. Cut in stages on thick material rather than forcing one pass.
- Stripped tension nut. Keep the thread clean and greased; grit is what chews the adjustment.
- Rust on the frame. A wipe with an oily rag after damp work. The blade itself should be replaced rather than cleaned.
- Storage. Hang the frame and keep blades in their wrapper, so the next blade you fit is straight.
Frequently Asked Questions
What blade length do these frames take?
Standard 300 mm blades, which is the size sold in the blade packs elsewhere in this range. Check the pin spacing if you are fitting blades from another supplier.
How many blades should I buy with the frame?
Two if you cut occasionally, ten if the frame lives on a workshop bench, and sixteen if the saw goes on site with both steel and softer materials to cut. Blades are consumables: buying them with the frame is cheaper than buying them one at a time.
Is an aluminium frame strong enough?
For general cutting, yes, and the light weight is an advantage at arm’s length. For heavy section steel all day, a heavier frame holds tension better.
Why does my hacksaw cut at an angle?
Usually because the blade is not square in the frame, or because pressure is being applied to one side. Check the blade seating first, then slow the stroke down and let the teeth cut.
Can I cut plastic pipe with a hacksaw?
Yes, with a coarser blade and light pressure to avoid chipping. For a clean square end on plastic pipe, a pipe cutter or a mitre box gives a better finish.
Buying the right one
If you have blades, buy the frame; if you are starting out, buy a frame with ten blades and keep spares in the toolbox. The aluminium alloy hacksaw frames in this guide cover frame-only and blade bundle options, so the kit matches how much cutting you actually do.
