Installing the "Upgrade Package" to our Zodiac CH 601 XL: Using an Angle Drill Attachment

As we've installed the "Upgrade Package" to our Zodiac CH 601 XL we've been using the same sheet-metal hand tools that are used in building and assembling an aircraft from a standard kit. One needed new tool is a right angle drill or drill attachment. We have used this extensively with the upgrade package to drill out rivets and to drill in the new parts.

While a regular straight drill gives you much better control and precision, a right angle drill allows you to drill in tight areas that you just can't access easily with a straight drill.
The right angle drill attachment works with an regular hand-held drill and typically sells for a lot less than a right angle drill which tend to be expensive (for a tool that you won't use often). Over the years we've looked at many of the right angle drill attachments on the market. Most are too bulky (with chucks) to reach tight areas, or are too cheaply made to drill round holes or to hold up.

One readily available and affordable right angle drill attachment that we do like is the Tight Fit® Right Angle Drill Attachment. It sells for about $35.00 (without the drill bits) and can be purchased through various suppliers.

We bought ours through McMaster-Carr: Tight-Spot Right-Angle Drill Attachment Part# 8787A14. You'll need #40, #30, #21 and #12 threaded shank drill bits: We recommend the "short" size (about 1-inch long, shown above) and not the "stubs" or "longs."

Here's a video clip of the right angle drill attachment:

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Comment by Timothy R Mix on December 4, 2009 at 1:52am
I find these posts very helpful...I am about to help a genetleman out on these upgrades and this will be great reference material! If anyone else is feeling that they may need help with their ungrade especially in the Northwest Region (Northern Cali, Oregon, Washington, Idaho, Nevada) I am a A&P IA that will be jobless after the first of the year and would be willing to come to you or you can come to me. I have extensive sheetmetal repair skills and the tools and would be willing to help you get your airplane back in the air. Call me if you are interested at 541.399.2731
Thank you.
Comment by Larry Webber on December 2, 2009 at 7:22pm
Mcmaster Carr does not carry the size bits we need for the right angle drill i got mine in stock from Manhattan Supply Corp msc
Comment by Stephen Mineart on November 30, 2009 at 12:59pm
As I plan for this project, a question comes to mind: Will the upgrade kit include hardware, such as rivets, nuts/bolts required for the re-assembly? I recall that ZAC tests the Avex rivets they include in the kits.
Comment by Stephen C. Martin on November 30, 2009 at 11:59am
Re the nose ribs: The latest drawings only show the later wing design with 3 nose ribs inboard of the fuel tanks. I have the older type with four nose ribs (like your demo aircraft). Will the upgrade parts apply to both types?
Also, I can't open the videos in these blog entries now although they were fine last week. Did your webmaster change anything?
Comment by Jonathan Starke on November 30, 2009 at 9:30am
Please note that McMaster-Carr will NOT Supply overseas customers, I tried to order the Tight-Fit Drill attachment, and they sent an email saying that they do not supply overseas customers.
Comment by Sebastien Heintz on November 28, 2009 at 7:29pm
With the new doubler, we are using the original nose ribs (and not new ones as shown in the above photo. This makes alignment to the skins easier and is a lower cost solution). I'll share more info on this later.
For specific questions, please use the Q&A Discussion forum hosted by my brother Mathieu (instead of the blog comments for Q&As).
Comment by Richard Simmons on November 28, 2009 at 7:06am
I guess I consider myself fortunate. I all but stopped a year ago of aggressive building watching the results of known testing being done. I coached my daughters softball instead! I just purchased an engine and was beginning again enthusiastically when all of this hit. Again!!!

I am thankful though and am looking forward to completing my project. I was anticipating Spring 2011 for maiden flight but it might be fall now.

My wings are still on a roll around and my fuselage has only few wires so I am in good shape to move forward on the rebuild. I will wait a bit longer on ordering my kit and watch others. Currently I will finish my firewall forward and do the Fuselage upgrade first, move it to the airport and them upgrade my wings while still at the house.

I tore down my work bench for the wings since I thought I was done. With that inmind, how acurate does the work surface need to be for the rebuild. Since all were drilled adn fitted in round on with flat surfaces etc. .

Can the rework be done on a not so flat/level surface?
Reinstalling the clecos should pull everything back into shape?


Comment by Jake Reyna on November 27, 2009 at 6:22pm
I find it hard to believe that ZAC didn't own one of these! I purchased the Deluxe Tight Fit at Spruce years ago ;-) and it came with the required bits, 20, 21, 30 and 40 plus other sizes that are listed. Not sure why they don't list the sizes I mentioned, but the drills are stamped. An excellent tool!!

To drill out rivets I use an 18 volt Milwaukee in low gear. Pre-drill an A5 rivet with #30 to enlarge the pilot hole and remove material from the inside to about surface height. Change to #20 and can pop the head off in 2 revolutions most of the time at a very slow speed. Change back to #30, remove a bit more material from the inside and then punch out with a Spring loaded Center Punch. No skin or hole damage, but practice is required and some are more difficult.

Milwaukee's are a bit expensive, worth every penny, I'm on my second set of batteries. Sears sells a similar Craftsman Drill for less. Obtw, I never use high gear.

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