Doors - How Tight?

[Kyle Boatright]

I'm doing final adjustments on my doors and wondered what the consensus is on how how much force the doors should take to latch? Without the seals installed, should extending/retracting the pins be relatively easy, a little stiff, or...?

I think the answer is that the mechanical latch (the two pins and the center latch) should be relatively easy to engage/disengage. Mechanically, mine are smooth, but get very tight on the last 45* of engagement. It feels like I'm fighting a couple of points on the cabin flanges where I need to relieve another 1/16" or so.

 

[Ron B.]

The seals give up a bit with time, so I started with a stiff closure and it eased up in time. this way you will have a better seal later. With that you don't want an exorbitant force needed now to close the doors, some where in between.

 

[Strasnuts]

There shouldn't be a lot of force

There should be no less than 1/4 " reveal between the inner door skin and the outside edge of the fuselage flange (with the seal off) for the common McMaster 3/8 bulb seal to squish into. If it is less than 1/4 you will have a lot more force.

A thing to watch is when the angled pins begin to seat they can bind against the cam shoulder resting on the fuselage block. I had this when building mine. I relieved the cam block by cutting a half circle where the cam shoulder sits (3/4" diameter). You can also lower the cam block. The way to test this is to remove the cam block and see if there is the same force on the pins while closing.

Other parts that can cause friction is the pushrods. Make sure the exit blocks are parallel and the hole drilled in the fuse is parallel to the pushrod travel. I counterbore all the PlaneAround blocks almost all the way through until the last 1/4". I keep that at 7/16 so the pushrods don't have to be perfectly lined up. I chamfer the big hole to the smaller exit so that they wouldn't catch.

Hope this helps

 

[Lynnb]

Put a little grease on the pins where they go into the fuselage and work them some. Mine were really tight till a friend came by, put some grease on them and said to just work them for a bit. Sure enough they became much easier and I can only guess will loosen up a little more in time.

Just my 2 cents.

 

[Flandy10]

Another point to consider when setting them up.. Temperature.

I set mine up during a warmer part of the year. When I tried to close them this winter, the aft pin wouldn't engage even with the PlaneAround system due to lack of door flex.

Left ATL at 28F and needed push on aft edge of door to close. Next day I departed from south FLA- 58F (still cold for Floridians) but it worked as it should.

Its happened more than once.


My 2 cents.

 

[Bill Boyd]

Pity Party invitation:

There should be no less than 1/4 " reveal between the inner door skin and the outside edge of the fuselage flange (with the seal off) for the common McMaster 3/8 bulb seal to squish into. If it is less than 1/4 you will have a lot more force.

A thing to watch is when the angled pins begin to seat they can bind against the cam shoulder resting on the fuselage block. I had this when building mine. I relieved the cam block by cutting a half circle where the cam shoulder sits (3/4" diameter). You can also lower the cam block. The way to test this is to remove the cam block and see if there is the same force on the pins while closing.

Other parts that can cause friction is the pushrods. Make sure the exit blocks are parallel and the hole drilled in the fuse is parallel to the pushrod travel. I counterbore all the PlaneAround blocks almost all the way through until the last 1/4". I keep that at 7/16 so the pushrods don't have to be perfectly lined up. I chamfer the big hole to the smaller exit so that they wouldn't catch.

Hope this helps

I'm at a frustrating point in my build. 13 months ago I spent a week molding a lip in place on the doors using the McMaster 1120A413 seal material as a female mold. Now a year later I'm sanding and filling doors for a final perfect fit flush to the cabin top and realize, Hey! - I should trial fit the seals before finalizing this little detail...

Somehow I seem to have slept through the threads (that I even posted in) about the proper set-up for using these seals instead of Van's: I have less than 1/8' clearance in some areas. Needless to say, my beautifully contoured doors won't come close to closing with the seals on. I've been grinding away at flox and pink prepreg for the last 3 days.

I think what Strasnuts meant to say is if you only have 1/4" of gap, you will need three linebackers pushing on the door to get it to close. I now have one door with .30" clearance all the way around and it still won't close with those 3/8" bulb seals on. Portions of the doorway are now so thin the seal won't stay on - almost knife edge. Time to add some flox on the inner doorway edge to build it back up. This will likely necessitate some spot repairs to the interior paint job.

I have decided not to sand the doorway any further into oblivion until I try the next (and only) smaller size seal McMaster seems to offer - a 9/32" diameter bulb on a 3/16" width C-channel. I'm hoping this will grip the sharp edge of the doorway better in more places, and that the 3/32" added clearance will let the door pins engage.

At this point I'm thankful that this screw-up, like virtually any with fiberglass, is fixable with sufficient time (or $$time$$ as Bob Nuckolls likes to say), effort and resin. The "elephant" just got a few dozen bites larger, but it's being eaten nonetheless.

 

[Carl Froehlich]

To answer your question, with no door seals the latch should be smooth and easy to operate. Find the binding and fix it before proceeding.

On the door seals I used simple McMaster Carr self adhesive seals attached to the door, not the door frame. They are now six years old and still in good shape. Get a couple of sizes and experiment - they are cheap.

Carl

 

[Kyle Boatright]

To answer your question, with no door seals the latch should be smooth and easy to operate. Find the binding and fix it before proceeding.

On the door seals I used simple McMaster Carr self adhesive seals attached to the door, not the door frame. They are now six years old and still in good shape. Get a couple of sizes and experiment - they are cheap.

Carl

Carl,

My experience is that heat softens the adhesive on all of the self-stick seals I've ever tried. 6 years and no problems for you?

Nice.

 

[Paddy]

Bigger Bulb

Before you pursue a smaller bulb size, consider that the seal will become stiffer in compression as the bulb diameter gets smaller. This is because of the ratio of bulb diameter to the thickness of the bulb wall.

I have found that using the next size up actually makes the seal easier to compress as it squashes down easily to its minimum flat thickness of about twice the bulb wall thickness.

 

[Carl Froehlich]

Carl,

My experience is that heat softens the adhesive on all of the self-stick seals I've ever tried. 6 years and no problems for you?

Nice.

Yep - not touched in over six years. When I first put then on I figured an every two year replacement (simple as dirt so no big deal). But not needed. If anything the adhesive seems stronger with time.

Carl

 

[Bill Boyd]

I went with the 1140A4 series because 1. others had, successfully, and 2. I wanted something to dress the doorway edge with a nice wear-resistant wrap. I will consider a seal on the door face as a last resort.

Different door seals are $50 a pop from McMaster. Relatively cheap, but only relatively. 9/32" bulb already on order. I will report results.

Carl - I have almost no binding on the doors woth the seals off. What little there is I expect to eliminate with greased pins and taking a little more thickness off the AeroSport cam block.

 

[Strasnuts]

I think what Strasnuts meant to say is if you only have 1/4" of gap, you will need three linebackers pushing on the door to get it to close. I now have one door with .30" clearance all the way around and it still won't close with those 3/8" bulb seals on. Portions of the doorway are now so thin the seal won't stay on - almost knife edge. Time to add some flox on the inner doorway edge to build it back up. This will likely necessitate some spot repairs to the interior paint job.

Bill,

I truly have 1/4" reveal around my door all the way around without the seal on. my doors are easy to close with very low effort for the last 950 hours. Even though you have it working with a smaller seal bulb, I would definitely check to see where the friction is. The added pressure of the seal is causing something else not to line up. I'm guessing it is the pushrod alignment but who knows. The doors are frustrating but the more time to make them work right the better in the long run. Call me if you think I could answer any of your questions. 801-580-3737

 

[Bill Boyd]

Generous offer, Sean. I won't hesitate to call if I need to.

My doors are things of beauty as far as fit, flush-ness and handle operation as long as there's no seal in place. I think this will just come down to a matter of making the gap such that the bulb is not fully compressed. No apparent reason that wouldn't be the case. I do have one door that's a tad stiffer than the other, but have not resorted to lubrication yet on either side. Trying to avoid surface contamination ahead of paint. The inside handles will close the doors with one finger; the outside factory handles require a whole-hand grip.

With .25" gap on one door and .30" on the other and a seal in place, there is no way to press the door down hard enough to make the thing sit flush even locally in the opening. The pins will not even start to engage. I doubt the issue is the PlaneAround latch, but I admit you might well know better. Just doesn't make sense yet to me it would be a latch issue.

 

[Kyle Boatright]

Generous offer, Sean. I won't hesitate to call if I need to.

My doors are things of beauty as far as fit, flush-ness and handle operation as long as there's no seal in place. I think this will just come down to a matter of making the gap such that the bulb is not fully compressed. No apparent reason that wouldn't be the case. I do have one door that's a tad stiffer than the other, but have not resorted to lubrication yet on either side. Trying to avoid surface contamination ahead of paint. The inside handles will close the doors with one finger; the outside factory handles require a whole-hand grip.

With .25" gap on one door and .30" on the other and a seal in place, there is no way to press the door down hard enough to make the thing sit flush even locally in the opening. The pins will not even start to engage. I doubt the issue is the PlaneAround latch, but I admit you might well know better. Just doesn't make sense yet to me it would be a latch issue.

I believe most of the "fight" from the seals comes from points closer to the hinge line. I'd start looking there. Have you put some play-dough or a similar material in the gutter, then closed the doors, to see what the real gaps are without the seals in place?

 

[Bill Boyd]

I suspect you are right about the upper portions of the door seal putting up more resistance. I haven't yet used modeling clay as a gauge, but have been progressively sanding and using a box end wrench of known thickness as a go/no-go gauge all the way around the door.

 

[Bill Boyd]

Pleased to report the smaller seal fixed the interference issue at the stage I was at, eliminating the need to grind more of the cabin top to powder. The 3/16" width is a good fit on the thin, almost knife edge areas of doorway I have created with all this relief sanding, and the 9/32" bulb makes a good seal all the way around with minimal resistance to closure. Two finger's pressure operates the door handles inside and out.

I'm a happy camper again. I may get this thing on gear before 2019.