Frequently Asked Questions

Frequently Asked Questions

Let's call this a running list, message us or comment if you have more!

1) What are safety flanges? Do I need them?

Many buffing wheels available for retail sale come with fixed or disposable center pieces in their clinch rings. Contrary to popular belief, their purpose is not for mounting with a locking nut but simply to keep the buffing wheel centered on your machine's arbor. Even with this piece, you need standard steel flanges to ensure that the teeth of your buffing wheel's clinch ring remain secure. Affixing a locking nut to the center can (at best) result in ineffective buffing (loose centers tend to spin in the buff when locked to the arbor) and at worst a dangerous situation (buffing wheel failure).

Over the years, we moved to centerless buffs that allow us to use custom-made, self-centering aluminum safety flanges. These help keep the buffing wheels centered on the arbor, keep the clinch ring secure, and allow for tool-less quick changes as we move through our process. We have four varieties: standard flanges for our 10" x 3", 12" x 5", and miniature 5" x 19mm buffs, as well as special "double" flanges that allow two 10" x 3" finishing airways to be mounted together.

Keep in mind that buffing wheels can still fail with safety flanges affixed, particularly when run at speeds beyond which they are rated - so keep that in mind when using and positioning a moving buffing wheel relative to yourself, others, and equipment.

2) Do I need a buffing wheel rake? How will I know when to use it?

  • Use on the edge of new buffing wheels to fray the face of the buff; if you don't the fibers will be unable to absorb compound properly, resulting in wasted material and a lack of cut until buffing the surface causes the face to fray on its own.
    • Dip treated buffs and double treated (double mill treat, mill and dip treat) buffing wheels may require a bit more raking initially as well as a break-in period (heat) to begin working normally.
  • Particularly on softer metals, you will see your buffing wheel turn colour at the edge (silver, if buffing aluminum) and feel the buff start to grab and want to pull away from you. This is a good indication the face has become plugged up with spent compound and aluminum you've removed for the surface. Give the wheel a light rake and re-apply fresh compound to continue working efficiently without scratching.

3) When polishing aluminum, do I need to sand first? What should I sand to?

Our shop's perspective is that unless we a) personally sanded and polished a surface in the last 6 months and b) it has been well maintained, aluminum should always be sanded (at least lightly) to remove natural oxidization from the surface prior to polishing. A mirror finish comes from light reflecting in a straight line; if you don't level the surface to remove pits, deep scratches, and rough/oxidized material you will never achieve the best finish (and you will fight compound getting stuck all over).

We normally recommend sanding as low as you need to to level most surface defects, and at least up to 600 grit (higher number is more fine). Some customers prefer to sand to 800 grit to make their cutting stage easier; we have done so in some cases to allow us to start our process with a Clear Treat Secondary Cut buff and Menzerna P164 Medium Cut (skip heavy cut).

If you are doing maintenance, try a test spot with the least aggressive option first (e.g., an untreated buff or flannel and Finish or Super Finish compound).

4) What buffing wheel/compound should I use?

Two factors: what material is it, and how nice of a finish do you want? We normally recommend at least a three-stage polish but sometimes you only want a cut and finish if you're going down gravel roads all the time.

Our standard aluminum polishing kit includes three buffs and three bars; we don't make big jumps here because we want to keep it as simple and easy as possible for newcomers. 

  • Menzerna 439T Heavy Cut + Hilzinger Grey Heavy Cut
  • Menzerna P14F Medium Cut + Hilzinger Yellow Primary Cut
  • Menzerna 480BLF Finish + Hilzinger 86/82 Untreated Mirror Finish

The goal when polishing is to produce a surface as level as possible so light reflects in a straight line. If you don't level it by sanding or by fully removing your aggressive cut marks, you will get a hazy reflection. Ergo, if you make large jumps in your process (super aggressive to super fine), much like sanding, you will be there a long time and go through a lot of material trying to do it in just two steps.

You can achieve an "equivalent finish" efficiently in just two steps by skipping the medium step; you will, however, have to work a little harder with the finishing compound and buff, and consume a little more material.

For a higher level finish, consider a three step process such as:

  • Menzerna 439T Heavy Cut + Hilzinger Grey/Yellow Heavy Cut/Primary Cut
  • Menzerna P164 Medium Cut + Hilzinger Clear Mill Secondary Cut
  • Menzerna P175 Super Finish + Hilzinger 60/60 Untreated or Molton Flannel Fine Mirror Finish

If including a sisal buffing wheel (i.e., on stainless steel), expect do do an extra step beyond these processes as you will (at minimum) need a Yellow Primary Cut buff and a 333/P14F Medium Cut to pull those sisal buffing lines (something more coarse if you got too aggressive with the sisal). Keep in mind stainless is a harder metal and while you can brute force sanding/cutting marks you missed early in the process on aluminum, you will be hard-pressed to do on stainless.

We put together a handy chart to help you decide on buffing wheel and compound combinations. At the end of the day, you can use any compound with any buff, but keep in mind that a more aggressive buff/compound will remove material faster at the cost of producing more buffing lines; a less aggressive buff will do the opposite (slower cut but cleaner finish). You trade off spending more time cutting for less time finishing, which can be very beneficial if your sanding/prep work is solid. You can even use the same buff/compound twice with subsequently less aggressive compounds/buffs to help step down your marks. Generally, we suggest not skipping more than one buffing wheel in your process at a time.

5) Will I need different equipment/materials to polish stainless steel?

Generally, yes. Most manufacturers make stainless-specific compounds, although Menzerna makes several compounds that will work efficiently on both aluminum and stainless (e.g., 439T Heavy Cut, P14F Medium Cut, P164 Medium cut, P175 Super Finish). Stainless specific compounds will tend to produce better results, faster (e.g., 333 Medium Cut, P126 Finish). Brown (tripoli) compound uses a softer, rounder abrasive that makes it ineffective at cutting stainless.

Another special tool we use is a sisal fiber buffing wheel. It's a special plant fibre that lends extra aggression to your compounds beyond that of a cotton airway. We have ours made with a special soft dip treat that adds a great deal of weight, enhancing durability and buffing action, while limiting extra buffing lines. Paired with appropriate compounds, it is capable of efficiently removing up to 180 grit (523 NG Super Heavy Cut) and 280 grit (439T Heavy Cut) sanding marks. We often use it with 333/P14F Medium Cut to produce an enhanced cut with less buffing lines than the more aggressive compounds and it still removes significant defects with relative ease. We typically recommend following up with 333/P14F Medium Cut on at least a yellow mill treat (primary cut) buff, but if you have difficulty removing your lines because you used the sisal too aggressively, simply try a more aggressive buff (grey mill treat heavy cut) or compound (439T Heavy Cut) and step down as normal. We offer a three-piece Stainless Expansion Kit designed to work hand-in-hand with the standard buffs and compounds included in our Aluminum polishing kits.

6) How fast should my buffing wheel be spinning (what RPM)?

Summary:

  • Higher RPM/surface speed causes the fibers in your buffing wheel (through centripetal force) to be pulled outward, and tighter.
    • Tighter fibres become less flexible, and more firm.
    • A more firm buffing face applies your compound more aggressively.
  • Higher RPM/surface speed also causes more compound to be applied to the surface in less time.

Ergo, higher RPM is generally desired for faster cutting action; it does, however, result in more harsh buffing lines.

  • Slower RPMs are desirable for finishing because they produce less harsh buffing lines; however, keep in mind:
    • You need enough friction and speed to absorb and apply compound
    • Lighter/thinner buffing materials (e.g, Domet flannel) need more speed to melt and keep high-melting point/dry compounds workable or they can produce inconsistent results and spots of black compound
      • As a result, heavier, higher quality materials can produce better results in many applications at lower RPMs
    • If a buffing wheel is spinning too slow and the material is too flexible, it can cause the material to flare out to the side, producing curved buffing trails at the edges (e.g., by fuel tank straps) that are more visible when beside a consistently vertically buffed surface

In sum, lower buffing speeds are desirable for finishing provided that you are spinning fast enough to keep your compound workable at a given ambient temperature.

7) How much compound should I apply?

This piece takes some practice with new compounds (time, pressure, etc.), but there are some pieces to keep in mind:

  • Menzerna compounds tend to go a lot further than North American compounds. They require less compound usage and stay on the buffing wheel longer. Our new Hilzinger buffs also retain this compound more efficiently than our old supplier's buffs.
  • Compounds with low melting points and high grease content will tend to require shorter applications to work best. Menzerna 439T Heavy Cut often throws off newcomers as excessive application can actually overlubricate the buff, causing the compound to smear and cut less effectively.
    • In this case, try to rake extra compound out of the buff, spread it out over the area you have to work with, and if necessary, mist a bit of Varsol/mineral spirits on the surface to help break down the excess. 
  • Compounds with high melting points and low grease content will tend to require longer applications to get the same amount of compound on to the buff.
  • Coarser, heavier, and firmer material at higher RPMs will generate more friction and allow for shorter compound application times. These buffs tend to be paired with cutting compounds which already have lower melting points and higher grease content (for lubrication).
  • Finer, lighter, and softer material at lower RPMs will generate less friction and require longer compound application times. These buffs tend to be paired with finishing compounds which already have higher melting points/lower grease content to allow them to finish cleanly.

8) My finish is cloudy/hazy/stripy. What did I do wrong?

Although commonly referred to as "burning" aluminum (which is not very easy to do), one has to keep in mind the basics of polishing any surface. You want light to reflect from the surface in straight lines; if light hits rough areas or deep scratches, it will have a tendency to scatter resulting in less clarity and depth.

As a result: if you fail to

  • 1) level the surface by sanding;
  • 2) fail to fully level your coarse sanding marks with fine sanding marks;
  • 3) fail to fully remove your fine sanding marks with your cutting step;
  • 4) fail to fully level your cut or colour buffing lines with fine compounds and soft buffs

You will achieve a less than perfect reflection. Keep in mind too, even if you do well, if light comes from a particular direction (90 degrees to your buffing lines), it is more likely to catch in those lines than light running parallel to your buffing lines.

How do you combat this? While you're learning, it can be hard to know when you've completed each of these steps to perfection. We sometimes suggest using a sharpie or grease pen - scribble over the prepped/cut/coloured surface, and then proceed. If any is still visible, it's because it's trapped in deeper sanding/cutting/colouring marks still and they need to be sanded/buffed more. This is often where we use "cross-cutting". During your heavy cut stage, it can be beneficial to cut from multiple directions to remove sanding marks. Beyond that, we will change the angle at which we do each stage of polishing: e.g., vertical during cutting, but at 30 degrees or horizontally when colouring. Do so until the vertical lines are fully replaced with your new lines, then go vertical again and blend.

We suggest working things like fuel tanks and large flat surfaces in small sections (e.g., shoulder width). Do so thoroughly for each stage of sanding and polishing. At the end of each polishing stage, do a slow blending pass across the sections you completed by walking sideways if necessary. Use cross-cutting to help ensure you have fully removed your previous stage of buffing or sanding.

9) How much pressure do I use?

This is a bit trickier to answer, but we do commonly see customers use too much pressure, which results in a few challenges:

  • a) Creates more harsh buffing lines, and makes your follow-up stage more time-consuming/challenging
  • b) Forces the plys of the buff wheel apart, sometimes even enough to keep abrasive from the surface
    • Let the abrasive do the work - each buff has a certain firmness to help give the compound a more aggressive abrasive effect, but pushing it past that point will reduce your cut and waste material
    • Using a higher RPM can allow you to buff with more pressure as it firms the edge of the buffing wheel - too firm of an edge reduces your contact area for abrasive, though, so you will have a more aggressive cut over a smaller area.

A buff whose edge has buckled - abrasive adheres to the edge only, so only limited quantities are in contact with the surface to be polished.

  • c) Reduces the lifespan of your buffing wheel
    • Excessive pressure often results in a reduced cut, which mean the buff has to be applied to a surface longer to get the same amount of work done (more abrasion and heat applied to the buff over time)
    • More pressure also causes more wear and tear per second, especially on rough surfaces, diamond plate, around holes, etc. - sanding/non-woven buffs are particularly susceptible to this

In sum, let the abrasive do the work. You can use more pressure when necessary, but don't cause the edge of the buff to buckle or you will have less abrasive in contact with the surface (since it's on the edge of the buff, not the side).

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