[f-AA] DZUS grommet flaring tools for wing head stud

[D]

Howdy all-  The top engine cowling on my L-16 developed a 1.5" crack adjacent to the wing top Dzus fastener.  With the help of my A&P, we've removed the doubler that supported the Dzus grommet and stud. We're about to install a new larger doubler to repair the crack.

A bunch of Dzus parts, including grommets, extra studs, snap rings,etc. came with my plane (thanks Sam!).  What I need is a tool, or some advice on another way, to flare the grommet that joins the cowl and its doubler, and holds the wing head stud.

Advice? Anyone have that tool that is nearby enough to loan it to me (Concord, CA).  Other ways to do it?  All my searches on youtube, etc. show ways to install the spring, but nothing about the grommet.

Thanks-

Don

[Rafael Gomez Blanco]

Get scarp metal and lots of the rings and practice  practice practice

_______________________________________________ Aeronca mailing list Aer...@westmont.edu http://mail.westmont.edu/mailman/listinfo/aeronca

[Mark Peterson]

I saw a clever use of bolts screws and nuts to install the grommet.   Auto racers use them too.   

Sent from my iPhone 

[Duane Fey]

Don,

 

I’m checking with Friends at KAPC, will get back to you shortly.

 

Duane

’46 Chief, N85981

 

 

 

From: Aeronca [mailto:aeronca...@westmont.edu] On Behalf Of D
Sent: Tuesday, July 03, 2018 8:30 AM
To: aer...@westmont.edu
Subject: [f-AA] DZUS grommet flaring tools for wing head stud

 

Howdy all-  The top engine cowling on my L-16 developed a 1.5" crack adjacent to the wing top Dzus fastener.  With the help of my A&P, we've removed the doubler that supported the Dzus grommet and stud. We're about to install a new larger doubler to repair the crack.

[David Rude]

Use a short piece of tubing with about 5/16" or 3/8" ID (measure to be sure, I can't recall the correct size)  and 9/16" OD for the tool.

 

If you do not have the tubing take a fitting like a 1/4" pipe union (has 1/4" MPT on each end) and drill it out to 5/16" or 3/8" and use that.

 

The grommets install with the flared side towards the tool, slam the tool with a hammer a couple times and you are done (assuming you installed all the correct parts :-)  )

 

Dave R

[Mark Peterson]

This way looks easy peezy....

http://spenceraircraft.com/hardware/pins-other-hardware/dzus-fasteners.html?p=3

Dzus Fasteners - Pins & Other Hardware - Hardware spenceraircraft.com Dzus fasteners are a type of proprietary quarter-turn lock fastener that are often used to secure skin panels on aircraft and other high-performance vehicles.

---

From: Aeronca <aeronca...@westmont.edu> on behalf of David Rude <dlr...@excite.com>
Sent: Tuesday, July 3, 2018 9:35 AM
To: aer...@westmont.edu
Subject: Re: [f-AA] DZUS grommet flaring tools for wing head stud

 

[Rafael]

Yeah my ‘38 did look to be easy to fix...

Sent from my iPhone

_______________________________________________

[John Rodkey]

Ingenius!

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--

John (poobah) Rodkey - N9361E 11AC at Goleta

[Mark Peterson]

All it takes is time and money my friend. 😀

Sent from my iPhone 

[David Rude]

I don't see how this method captures the Dzus fastener, never saw it done this way.

 

The way I have done them and it does hold the Dzus fitting captive is as follows.

 

Put the Dzus in the hole, put something heavy and metal against the Dzus head with Dzus head down.

 

Then put the sleeve over the Dzus with the flange toward the inside of the cowl (up in this situation).

 

Slide the tool against the sleeve flange then hammer the tool against the flange so the skinny end of the sleeve follows the radius of the underside of the Dzus head. It curls around at the outer surface of the cowl and captures the Dzus.

 

Been doing it that was since the 80's.

[Rafael Gomez Blanco]

And can never have both at the same time or with the right amounts either lol

-----Original Message-----
From: Mark Peterson <mrpet...@msn.com>

[D]

Thanks All-  Dave R's post addresses the problem I was worried about after reading everyone else's.  It will be tricky with a wing head type Dzus, but it is important to "shrink" the inside radius of the grommet AFTER the Dzus stud is in place.  If not, the fastener will fall out when not attached tight.

Don

\\>>>>>>>>>>>>>>>>

[Mark Peterson]

Have you checked into the split clips for them?

Sent from my iPhone 

[David Rude]

get a steel "block" to hammer against and cut a slot in it for the wing to slide into with a cut off wheel in an air tool or angle grinder.

 

 

 

 

-----Original Message-----
From: "D" [whites...@gmail.com]
Date: 07/03/2018 03:01 PM
To: aer...@westmont.edu
Subject: [f-AA] DZUS grommet flaring tools for wing head stud

[donharvie]

Depending on the style of Dzus fasteners it may be possible to make your own tools. Here are some photos of the ones I turned up on the lathe when replacing the worn out Dzus fasteners on my Auster LH cowling.

https://harvie.cable.nu/gallery2/main.php/v/Don/Flying/VH-CRR/cowling-dzus/?g2_page=1

The stainless sheet is cut to copy the RH cowl which are originally off a Dehavilland Mosquito.

Don H

Sent from my 'phone

[Don Whiteside]

Mark-  THanks!  Just what I was looking for!

Don

[D]

Here's  quick update.  I discovered, in the group of parts that came with 04C, a group of Dzus "snap rings".  I think those are intended to slip over the shaft on a replaced Dzus, and retain the fitting.  I'll try it and let the group know.

http://www.aircraftspruce.com/catalog/hapages/snaprings.php?clickkey=3052681

Don

[Mark Peterson]

I’ve got a set of wing and a regular to replace on my cowl.   I hope to dreamel the old ones off slip in the new ones and use the snap rings  

Sent from my iPhone 

[Don Whiteside]

YEs, that's my plan also.  Don

[Sam Burke]

Don,
Sorry I was unable to visit you at the airport this morning, we were lucky to get through San Jose before traffic started to build up. We got home at 8:30.
How did the doubler installation go? Since the top cowl never fit right you might consider making a new cowl, hinge and all. It would be an interesting sheet metal project.
Regards,
Sam Burke
Solvang looking for another project!

[D]

Sam. sorry I missed you. 

All- I've posted on a separate thread the story of my slight success with this and a description.  Cowling will go back on today and hopefully I'll FLY!!

Don