The Toledo Show: R/C Model Expo!
Greg Gimlick
maelectrics@gimlick.com
If you read my column, you already know that I look forward to the annual Toledo Show: R/C Model Expo the way a kid looks forward to Christmas. It’s always a special event and it’s my first chance to see many of the year’s new releases.
The event has changed throughout the years, but it’s great, and one of the few chances to see so many manufacturers, distributors, and vendors in one place. The big names are usually there and each year, new businesses come to show their stuff as well.
It’s almost here, so mark your calendar to be in Toledo, Ohio, at the SeaGate Convention Centre, April 7-9, 2017!
A power guideline chart.
It’s almost here, so mark your calendar to be in Toledo, Ohio, at the SeaGate Convention Centre, April 7-9, 2017!
The Ohm’s Law pie chart.
Tools for Free
Maybe I should have said planning tools, but I wanted to draw you in! As you plan your shopping trip to Toledo, you might also be planning to build a new, electrified model. If you’re new to electrics, or you haven’t gotten in deep enough to convert your own airplane, these two charts can be a lifesaver—and they’re absolutely free!
Many modelers don’t know Ohm’s Law, and others don’t often think past the volts x amps = watts portion of it. This pie chart breaks it all down for you. The chart also garners a lot of hate mail whenever I reference it.
Modelers tend to change the abbreviations to commonly used letters, while engineers stick with the technically correct letters on the chart. Don’t get hung up on that stuff. Use the chart to understand the relationships and use the abbreviations that make sense to you. If “W” works better for you than “P,” then use it! Depending on the publication in which the abbreviations are used, they’re accepted or argued.
The second chart breaks down power-to-weight planning for levels of performance. With the improvement of batteries, motors, and ESCs, it has become easier and easier to achieve whatever level you’re targeting.
Just because you can set up an airplane for 150 watts per pound doesn’t mean that it’s the best choice if you only need 75 watts per pound. Why? Motors have a best-efficiency range, and that’s the area you want to target for your primary flight requirements.
If you overpower an airplane and then operate it at half throttle or less all of the time, you’re probably running the motor in a less-efficient range. This causes excess heat and further decreases efficiency. Check the manufacturer’s recommendations for efficiency and use that information when planning.
Buy Cheap—Buy Twice
Friend and electric guru, Keith Shaw, has preached this for as many years as I’ve known him. Keith knows more about electric flight than most of us ever will, and I’ve never seen anything that he has built not fly spectacularly.
Keith uses good equipment—but that doesn’t mean it’s always the most expensive. Don’t confuse “cheap” with “inexpensive,” although they often go hand in hand.
The Himax motor shown in one of the photos is relatively inexpensive, but it’s far from cheap. The quality of construction is evident when you disassemble one. These Himax motors have beautifully spaced and secured magnets, with separators between each magnet, to help them stay aligned and secure.
Another photo shows a cheap motor that was poorly constructed and obviously came apart. The cheap motor cost half of what the Himax motor did, but when it self-destructed because of poor construction, it also caused a fast current spike that destroyed the ESC, becoming doubly expensive.
I can only blame myself for not following Keith’s sage advice. I tend to experiment based on recommendations that I receive in
emails. That’s part of what I do, but it doesn’t always work out well.
Many good-quality motors are available that won’t break the bank. If your motor’s windings look like blindfolded monkeys did them, chances are they weren’t done carefully and you’ll pay in the end. Not all bearings are created equally and better motors use better bearings. Pay a little more up front and save in the long run.
High-Power Connectors
I’ve received quite a bit of mail asking about recommendations for connectors that will handle high-power requirements. There is no substitute for quality and surface contact area with such demands. Castle Creations has a nice 6.5mm bullet connector set that is housed in a plastic case that is easy to grab ahold of.
Most of you know I’m a fan of crimping Anderson Power Poles and I’m not a fan of soldering, but when it comes to big power, the Castle Creations connectors are the way to go. This is not an area where you want to cheap out, so paying slightly more for quality is both more efficient and safer.
Wrapping It Up
I hope to see you at The Toledo Show: R/C Model Expo. Stop by the AMA booth and say hello. Be sure to check out all of the electric entries on the competition tables. You might even run into some aeromodeling greats such as Keith Shaw.
SOURCES:
The Toledo Show: R/C Model Expo
www.toledoshow.com
Castle Creations
(913) 390-6939
www.castlecreations.com
