Where to Get Thor Air Filter Media Replacements (Including Legacy Microclene Machines)

As someone who has spent over 25 years at the lathe, I know first-hand how quickly fine wood dust fills a workshop. You can feel it in your throat before you see it settle on surfaces. Over the years, I've relied on ambient air filtration as a critical part of keeping my lungs healthy, and I've helped hundreds of customers do the same. If you own a Thor or Microclene air filter and you're wondering where to find replacement media, this guide covers everything you need to know.

Why Your Thor (or Microclene) Filter Media Needs Replacing

Thor filter media is made from polyvee glass manufactured to the EU4 (G4) standard. Unlike cheaper filter pads that simply slow airborne particles, this media physically traps dust. It captures 95% of particles at 2 microns or larger, 80% down to 1 micron, and 65% down to 0.4 micron. That level of performance comes at a cost: the media gradually saturates and loses effectiveness over time.

Thor recommends replacing filter media every 200 to 400 operating hours, depending on the type of material you work with and how often the machine runs. Between full replacements, you can extend the media's useful life by lightly vacuuming the outer face or carefully tapping it out over a bin. These interim maintenance steps help, but they are not a substitute for fitting fresh media when the time comes.

Staying on top of media replacement is a genuine health issue. Wood dust is classified by the IARC as a Group 1 confirmed human carcinogen, linked to cancer of the nasal cavity and paranasal sinuses. The UK Workplace Exposure Limit for hardwood dust sits at 3 mg/m³ (8-hour TWA), and the EU tightened its binding limit to 2 mg/m³ in January 2023. HSE research has specifically flagged sanding as one of the highest-risk activities for dust exposure, with 17.6% of hardwood or mixed dust measurements exceeding the WEL. For woodturners and sanders, that makes filter maintenance a compliance and health priority, not just housekeeping.

It's also worth noting that Thor machines use Swiss-made, thermally protected, spark-proof motors. The polyvee glass filter media is designed to work safely within that environment, giving you confidence that the whole system is engineered with workshop safety in mind.

Thor Filtration and Microclene: Understanding the Connection

If you've owned a Microclene air filter for any length of time, you'll know the frustration of trying to source replacement parts since the brand disappeared. Microclene machines were originally manufactured by Acrol Limited and became a fixture in UK woodworking workshops over many years.

Thor Filtration was established in 2017 specifically to take over the design and manufacture of the Microclene range after Acrol ceased production. The important detail: Thor had always been the metal fabricators for Microclene. The machines use all the same components, including the motor. This is not a copy or a third-party substitute. It is a direct continuation of the original product line.

That means Thor replacement filter media is fully compatible with both current Thor machines and older Microclene machines. If you own a Microclene unit and have struggled to find media since the brand went quiet, Thor media is the authoritative answer. Thousands of UK woodworkers have been searching for exactly this information.

Thor machines are also being rebranded and sold under other machinery manufacturers' names, which further confirms the quality and reputation of the product line. If your machine says Thor, Microclene, or another brand on the label, the media inside is the same.

Full Compatibility Chart: Which Thor Media Fits Your Machine?

This is the cross-reference information most Microclene owners are looking for, and it can be surprisingly hard to find elsewhere. Here is the complete list of Thor replacement media and their compatible machines:

• TF250 (pack of 5, each filter 25mm thick) — fits Thor TF250, Microclene MC200, and Microclene MC100
• TF450 — fits Microclene MC400
• TF470 — fits Microclene MC420
• TF810 — fits Microclene MC760
• TF1250 — fits Microclene MC1200
• TF1260 — fits Microclene MC1210
• MC780 / MC1000 — for legacy Microclene units of those model numbers

Note that the TF250 comes as a pack of five filters. Each filter is 25mm thick, so make sure you know what you're ordering before comparing prices with single-unit media for larger machines.

Before ordering media, it's worth confirming your machine is properly sized for your workshop. The TF470 suits workshops up to 40 m³ (roughly a single garage). The TF810 covers up to 78 m³ (a double garage). The TF1260 handles up to 120 m³ (a triple garage or large workshop). Industry guidance recommends 6 to 10 complete air exchanges per hour. For a 35 m³ workshop, that means you need a unit delivering at least 350 m³/hour of throughput.

If you're unsure of your machine's model number, check the label on the unit itself. If your model isn't listed here, contact a specialist stockist who can help identify the correct media.

Where to Buy Thor Air Filter Replacement Media in the UK

Several reliable UK stockists carry Thor replacement filter media. Here are the main options:

• CXS Tools — we stock Thor replacement media and offer personal customer service with direct phone and email contact. If a particular media size is temporarily unavailable, we can source products on request. Our founder-led approach means you're speaking to someone who genuinely understands the products and can advise on compatibility.
• Poolewood
• Toolpost
• Biven Machinery Sales

It's worth noting that several major UK stockists have shown Thor air filter machines as sold out, reflecting ongoing supply constraints. Replacement media, however, tends to remain more available. If you already own a machine, you should have no trouble keeping it running.

For readers outside the UK, international stockists include Bildhau in Germany and Willy Van Houtte in Belgium.

Replacement media is priced at approximately £11.74 to £17.85 (ex-VAT) per unit or pack, depending on model size. We strongly recommend buying genuine Thor media rather than generic alternatives. The EU4 G4 polyvee glass specification is what delivers the stated filtration performance, and substituting cheaper material undermines the whole point of running an air filter.

Thor Filtration is a UK manufacturer. Buying from a UK specialist stockist means faster fulfilment and access to knowledgeable pre-sales advice when you need it.

How to Know When Your Filter Media Needs Changing

There are a few clear signs that your media is due for replacement. Look for visible grey or brown discolouration across the surface of the filter. You may also notice reduced airflow from the machine, or a general increase in dust settling on workshop surfaces.

For interim maintenance, lightly vacuum the outer face of the media or carefully tap it out over a bin. This extends the service life but does not eliminate the need for a full media change.

The 200 to 400 hour replacement range exists because different materials clog the media at different rates. Fine hardwood dust from turning or sanding saturates media much faster than coarser softwood dust from general carpentry. Woodturners specifically generate very fine ambient dust from the lathe, often finer than dust produced by hand or machine sanding. If you're primarily turning, expect to replace media closer to the 200-hour mark.

The urgency of proper filter maintenance is underlined by enforcement data. During the HSE's 2022/23 Dust Kills campaign, 78% of businesses inspected failed to adequately protect workers from respiratory sensitisers, resulting in 402 enforcement actions. For professional workshops, filter maintenance is not optional.

A simple tip: keep a log of your machine's operating hours. Even a notebook next to the unit will do. It takes the guesswork out of replacement intervals and helps you stay consistent.

Getting the Most from Your Workshop Air Filtration

An ambient air filter is one layer of a complete dust management system. It works best alongside dust extraction at source, such as a dust extractor connected to your sander or lathe, rather than as a standalone solution. The air filter catches the fine particles that escape source extraction, and together they cover the full spectrum of dust sizes.

At CXS Tools, we stock abrasives from brands including Mirka, Indasa, and VSM that are proven to reduce workplace dust by up to 90%. Pairing quality abrasives with a well-maintained air filter gives woodworkers and decorators the strongest possible protection against dust exposure.

Decorators and DIY enthusiasts sanding walls or ceilings generate fine plaster and paint dust that poses its own respiratory risks. Thor air filtration and regular media replacement matters just as much for this audience as it does for woodworkers.

Approximately 19,000 new UK cases of self-reported work-related respiratory disease are recorded annually (HSE, 2023). Ambient air filtration is a long-term investment in your health, not just a workshop accessory.

Finding Thor Filter Media: A Quick Summary

Three key points to take away from this guide:

1. Thor media is the correct replacement for both current Thor machines and legacy Microclene machines. It is a direct continuation, not a third-party alternative.
2. The compatibility chart above makes it straightforward to identify the right part number for your machine.
3. Several reliable UK stockists carry the media, even when machines themselves are sold out.

Before ordering, check your machine's model number and match it against the compatibility list. If you're unsure which media you need, or if your model isn't listed, get in touch with us at CXS Tools directly by phone or email. We're happy to help identify the right part, and if we don't have it in stock, we can source it for you.

Replacing your filter media on schedule is one of the simplest and most affordable steps you can take to protect your lungs. At under £18 per replacement, there's no good reason to put it off.