Indicators are sold with lug backs, flat backs or both. Lug backs are a good way to mount indicators on most truing stands. As an example they make for drop-in replacements on Park Tool TS-2/3/4 truing stands. Flat backs are an alternative if you plan to mount indicators by their stems and want to keep the rear tidy. Magnetic indicator mounts and most tensiometers use a stem clamp design.
iGaging indicators include both styles so you can switch back and forth. Mitutoyo indicators are sold as one style or the other, however you can purchase extra backs to convert a flat back to a lug back or vice versa. By Mitutoyo part numbering conventions, models numbers ending in the letter ‘B’ ship with flat backs. Model numbers not ending with ‘B’ ship with lug backs.
Thinking about adding digital indicators to your truing stand but not ready to dive into visualization just yet? This post contains pointers to digital indicators you can add to your truing stand so visualization is an option when the time comes.
Islandix Wheel Analytics interfaces with digital indicators that conform to the Mitutoyo Digimatic SPC standard. This entails the use of a special uplink cable (included with Wheel Analytics) and a signalling protocol for transmitting data on the wire. This means you can’t go wrong with Mitutoyo indicators but the market is served by compatible brands too.
The Mitutoyo 543 range is a great choice. 543-5XX and 543-7XX models are my preference. You’ll see lots of options with different feature combinations depending on your preferences. Say, for example, you want to replace your Park Tool analog indicators with Mitutoyo 543. Look for a model with #4-48 UNF threads, which lets you re-use the nice #4-48-threaded indicator tips from your Park Tool kit. The Park Tool truing stand attaches indicators using a lug back so pick a Mitutoyo model with this feature (all model numbers except those ending in ‘B’). Compatible indicators for this specification include 543-506, 543-507, 543-783, 543-792, 543-793 and 543-796 among others. All Mitutoyo products are premium quality and the least expensive are perfectly suitable for driving visualizations. Finding a model below $200 USD is pretty easy, as low as $175 on a good day.
Other brands also implement the same standard, which means there are options at difference prices. For example iGaging 35-705-10 and 35-700-10 have the same data interface but cost less. Both models use #4-48 UNF threads and both include lug backs, which make them drop in replacements for Park Tool analog indicators. Again the least expensive are suitable for driving visualizations. Finding iGaging indicators below $100 USD is pretty easy, often as low as $65.