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henrysamson
07-22-2012, 01:20 PM
I have a model IV with the single latch at the bottom of each door. They seem to work fine as far as holding the doors tightly closed. I just tried installing the plastic "detent rivets" that are supposed to secure the latch in one of two positions, open and closed. They lasted about 2 open close cycles before snapping off. I have gone through several trying to get them the correct length without success.

So, have any of you come up with any better ideas for using these latches. I really don't want to redo and install another type of latch. I have searched the forum but have not seen anything helpful for my latches.

Also, is there a special tool for inserting "roll pins".

Thanks!

Henry

jtpitkin06
07-22-2012, 04:58 PM
Also, is there a special tool for inserting "roll pins".

Thanks!

Henry

Roll pins may be pressed in or driven in with a pin punch. I don't like to beat on things where the structure might get damaged, so I prefer to press them in.

For most roll pins I use a "C" clamp to press the pin into position. To aid in getting the pin started, I will often use the belt sander to taper the end at a very shallow angle and round the tip to allow for minor misalignment of the parts. With this little bit of prep on the pins they seen to go in with a problem. Without it.... GRRRRR.

To remove a pin with a press I've tried the "C" clamp and socket but sometimes it's tough to hold all the parts and get pressure on the pin. Removal is pretty easy if you have a smaller diameter pin and a modified "C" clamp. Just drill a hole through the pad on the clamp (opposite the screw) as a passageway for the exiting pin.

I have quite a few modified clamps and it's surprising how many other uses I find for the hole in the pad.

John Pitkin
Greenville, TX

HighWing
07-22-2012, 05:46 PM
Henry,
I built my first of two Model IVs - both factory shipped in the early 90s. I still have the pins mentioned in my left over parts drawer - saw them the other day. I flew for 900 hours with no detent provisions on the door latches and never had a door pop open in flight. This time, I fabricated my own latches based on the original ones. I wanted a locking mechanism this time. If we are talking about the same thing, I think I would just forget the plastic parts.
Lowell

henrysamson
07-22-2012, 05:59 PM
John, thanks for the roll pin advise. Just before you posted I went out with a pair of regular old slip jaw pliers and was able to press them in fairly easily. It did dent the powder coat and paint on the side I did not insert the pin from but it was an easy touch up. A c-clamp may have done a neater job. I did use a c-clamp and socket for the lugs on the prop hub. Per John McBean's instructions.

Lowell, I'm glad you did not have any problems with the doors popping open. I am thinking of bonding two thin strips of aluminum to the striker plate such that the latch fits snugly in between. But, I may just leave them and see how it goes. They seem pretty tight I am just worried about hitting the knobs by accident and having the door pop open.

BTW, it is coming along . . . thanks for all the help!

t j
07-22-2012, 06:45 PM
The plastic detent pins came out of my door latches after a couple times opening and closing too, so I just left them out. A door came open in flight one time on my second test flight. I just bent the tang a little to make it close tighter and no doors have opend on their own since.

I also left the round knobs off. I did put an extra web strap on each door on the bottom of the frame right in front of the latch to pull on when operating the latch. The latch handle will bend if you pull on it when latching the door.

Part of my passenger briefing is to explain how to open and close the door without bending the latch handle.