Profile notch?

[Diemjoe]

Looking through some of the photos, I have noticed that builders indent their Profile curve a bit at the galley opening. I was hoping to get more information on the why. Does Hurricane hinge selection depend on it? how much of an indent? Does the galley roof extend out to the to the skin edge of the wall? In short, can someone provide design considerations for the indent? Thanks.

[backstrap bandit]

The notch is not necessary if you use the offset hurricane hinge however if you use the traditional hurricane hinge you have to notch approx 3/8 to allow the hatch to line up even with body

[grant whipp]

Hey, Don!

The "notch" or "step" in the profile behind the body-side galley lid hinge beam IS a matter of so-called "hurricane hinge" choice, which really boils down to aesthetics, as both the original offset-type (1/4" offset) and newer-style 0-offset type function exactly the same (although, as advertised, the 0-offset version has a tighter nesting pocket resulting in less slop in the fitment of the two pieces). The offset hinge lifts the surface plane of the hatch lid 1/4" above the surface plane of the roof, and as a result, the "crown" is about 3/8" higher, and as already stated, requires no notch or step cut into the profile. The 0-offset hinge keeps the roof and hatch surfaces on the same plane, has the lower "crown", and does require a bit of a notch or step, but not nearly the 3/8"-or-so called for in the Generic Benroy (and other) plans ... you really only need 1/8" to 3/16", and you do NOT have to carry that all the way to the threshold (you can taper it off over 12"-or-so).

How you plan to trim out both the body and the galley lid can have an affect on which hinge you choose, as well, so you should consider all those factors when planning your trailer ... and you should definitely discuss your wants & needs with whomever you are considering purchasing your hinge(s) from and get their thoughts and recommendations (after all, they are the ones who use-and-iinstall them all the time! ).

If you have any questions about either style and their installation (including the original-style for KITs & Ken-Skills). you can always e-mail me at [email protected]
Good Luck, and as always ...

CHEERS!

[Diemjoe]

Thanks Grant,
You are on my list to contact regarding the hardware when the time comes. Hopefully sooner than later. I will check out the hinge options and get back to you with questions.

[halfdome, Danny]

but not nearly the 3/8"-or-so called for in the Generic Benroy (and other) plans ... you really only need 1/8" to 3/16",

Grant, I believe the 3/8" is to allow for the 1/8" plywood skin on top of the flush galley lid.
That brings it down to 1/4" or less.
Anyhow that's how I've always interrupted how to do it.
Danny

[grant whipp]

but not nearly the 3/8"-or-so called for in the Generic Benroy (and other) plans ... you really only need 1/8" to 3/16",

Grant, I believe the 3/8" is to allow for the 1/8" plywood skin on top of the flush galley lid.
That brings it down to 1/4" or less.
Anyhow that's how I've always interrupted how to do it.
Danny

Actually, it doesn't, Danny!

If you cut a 3/8" notch into your sidewalls and then add 1/8" plywood over the top, then 1/8" plywood over the top of your hatch framing, you still end up with a 3/8" step. IF, however, you "rabbit" your roof beams so that the 1/8" plywood sets down in and flush with the top of the side walls, then yes, your scenario is more-or-less correct (but, why would you go to all that trouble?). I've run it around in my head time & time again and still can't come up with a good reason for the 3/8" step! Even if you allow for the possibility of using 1/4" plywood roof & hatch sheathing, you still come up with a 3/8" gap! Maybe if you are using thick aluminum angle for trimming the top of the galley walls, but there again, why?

All of my trailers have 1/8" plywood over the top of the hatch framing, all of my trailers since 2002 have the 0-offset hinge, and all of them needed less than 1/4" of a step. Due to the compressibility of my Hatch Seal, everything I build from now on will have only a 1/8" step.

What ever works, though, I guess ... ...! As always ...

CHEERS!

[halfdome, Danny]

This forum has been promoting the 3/8" galley wall drop for years and it seems to work for me.

Grant I don't do it in the manner you described.
I always put two layers of 1/8" plywood on the roof, no matter what others feel, it's just my preference.
I then bearing route with a rabbit bit half way into the galley wall.
I then finish up with a straight top bearing bit to obtain a 3/8" step on the galley walls.
With the lid temporarily attached to the roof and threshold (see photo) with 3/8" gap for your hurricane hinge and 1/4" at the threshold for your seal I end up with a shy 5/16" gap on the walls.
I then put plam (plastic laminate) on the raw routed edge to end up with a 1/4" gap.


So your saying I only need 1/8" to 3/16" gap?
I guess I can add another strip of plam to the inside edge of the lid where your seal goes or I can add 1/8" aluminum instead of the plam to the already routed galley walls.

I understand you're not suppose to crush the seal past a certain point (50% ?) as it will be less effective in sealing out water.
Since your galley seal is .400 or a bit over 3/8" thick I'd figure a minimum of a 3/16" ( more than 50% ) gap would be necessary and a 1/4" would be okay.

It's good this topic has come up while I can still make some changes.
Thanks, Danny

[backstrap bandit]

With my experience I would say eliminate the notch and use the offset hindge. You see I cut my notch as per instructions and it seems I have more than 3/8 and it's not real consistent been trying to figure out what I want to do I think part is the notch and other part is hatch side spars

[grant whipp]

So, Danny ...

... if I'm understanding your build technique correctly, you are not cutting your "notch" into the walls at the time you cut out your walls, but after you've installed the roof sheathing ... correct?

I think that's what is tripping me and a lot of other folks up ... they're cutting the step in at the same time as they cut out the walls, and end up with too much gap (IMHO, anyway) ... ...? I've been doing this for a long time, and I have what works for me pretty much down pat (though, I'm always looking for ways to improve the function as well as the looks), but it was this latest build that made me re-think the whole "step" issue. What it all boils down to, it seems, is that however you choose to build your trailer, you should end up with nor more than 1/4" gap between the top of your galley walls and the part of your hatch that overhangs it (before any moldings go on).

What works for Danny might not work for you ... what works for me might not work for you ... lots of factors come into play, including materials chosen, the experience of the builder, the conciseness of the plans that you may (or may not) be following, and whether or not you have decided to deviate from said plans. And (I have to admit ... others should, too), sometimes we get stuck in doing things a certain way and thinking it is the only way ... ...(it's one of the reasons I've responded to this thread ... to see if there is a valid reason for cutting the 3/8" notch, and to see if even the designer can respond with a decent explanation!).

Maybe for some, going with the offset "hurricane hinge" will eliminate all of this hassle and discussion, and that's fine ... if it works for you, go for it ... but for me and my sense of aesthetics and function, I will always favor and continue to use the 0-offset hinge ... not because that's what I sell, but because that's what works for me! However you choose, continued good luck, and as always ...

CHEERS!

[Diemjoe]

Thanks everyone for all the responses. I am going to sit down before the wall profile gets cut (soon) and put all this info into some drawings.

[halfdome, Danny]

So, Danny ...

... if I'm understanding your build technique correctly, you are not cutting your "notch" into the walls at the time you cut out your walls, but after you've installed the roof sheathing ... correct?

Correct Grant, as things may change with the thickness and doing it after the roof plywood is installed eliminates problems.
With your vast knowledge in the teardrop community I'll go with a 3/16" gap by simply adding one or two extra layers of plam to my galley wall edge to obtain 3/16".
Creative shading with a brown marking pen will make the extra plam laminations almost unnoticeable to the average person.
Adding anything to the underside of the lid where the seal is applied would make it even more difficult to make the RV insert molding cover it all at the tight radius of my lid where the annealed aluminum is resistant.
With the 1/16" less gap (from 1/4") the RV insert molding will cover more.
Thanks, Danny

[aggie79]

I did the same as Danny - cut the "notch" after the walls were in place and after I did my hatch framing. The reason I did this was because the outer profile of my hatch "ribs" matched the outer profile of the walls before the notch. This allowed me to frame the hatch in place referencing off of the outer wall profile.



Here's a close-up of the rib and wall before the notch.



Not notching the wall also allowed me to run the hatch skin "wild" and later be able to use a bottom bearing flush trim bit in the router to cut the hatch skin to width.



As Danny says, cutting the notch is pretty easy. It's done in two steps with a router. First cut a rabbet to the depth of the notch that you want.





Then finish the notch by using a flush trim bit with a bearing. It's easier if you use a top bearing bit so you can route from the outside of the trailer.

[dales133]

How do you determine the depth of the notch? From what I understand it's to stop the hatch seal over compressing...is this correct?
If so how is this calculated?
Regards dale

[aggie79]

A rule of thumb is for the clearance for the seal/weatherstripping is to be about 1/4 to 2/3 of the thickness of the seal. My "notch" is 1/4". On top of the galley sidewall I added aluminum trim that was 1/16". I also added .040 aluminum on the underside of the hatch skin that overhangs the sidewall. This left a clearance a little less than 3/16" inch. The D-shaped seal I used was 1/4" tall, so when the hatch is closed it "squishes" a little more than 1/16" (or 1/4 if the 1/4" seal height.)

[dales133]

Thanks for the explanation, so aproximatly compress 1/4 of the seal