DIY hatches / removable panels in welded aluminum floor

Well, I know understand a few options and pros and cons of each thanks to you guys.

I will likely cut out and tack in side sections in a couple of months. Then I can look at or mock up the various options to see which one best suits my needs.

Thanks everyone!!

 

Only flush as stated before. You can use a flat bolt as a pop up handle.

 

I only saw this thread lately but would offer the following observations

The pipe gunnel looks as if it would be quite flexible and could be easy to bend if you come into a dock hard. You could put in a 4 -5 inch gunnel, (also a great place to step on getting into and out of the boat) by adding in another pipe similar to the one that you have, inboard then putting in a flat plate to join the two pipes together. This would provide a spot to mount cleats

I notice that some of the frames forward and the bulkhead around where there might be a anchor rope locker is a frame welded to the middle of the hull where the flex in the hull can cause work hardening and subsequent cracking. Ie a frame with rigidity terminating into the flexible sheet.

With regard to the front frames that do not go to the gunnel, if you increase the width of the gunnel as suggested above, I would add on to the frame and continue this up to the gunnel so you do not have a hard spot in the sheet. Same with the front bulkhead

The detail is not clear around your center console. We have repaired many welded in consoles on home built and factory built aluminum boats as the vertically cantilevered console with vibration causes another work hardening problem where the vertical pieces are welded to the stringers.

We have repaired these by welding in a 1/4 inch by 2 inch high by 12 inch long, (varies with the length of the console) onto the top stringer then bolting the console to this. We would on this unit, bolt on the console (which needs a corresponding 1/4 inch strip) to the 1/4 inch strip with about six 1/2 inch bolts. The bolts are snugged up and
provide a little movement so as to limit work hardening. A company that builds many center console boats, probably 200 or more to date has adopted the same process and they have said that they have never had a console break at the stringer/bolt interface

Just some thoughts

 

Hi Barry. I appreciate the detailed points and advice. The boat is far from finished. I just wanted to see how it worked and get some satisfaction and incentive to continue finishing it out, mostly this coming winter.

I already have 4 or 5 inch flatbar and extra pipe to do exactly what you suggest with the gunnels. In addition, will also weld in top extensions to frame tops so they connect to gunnels as you say. I raised the sheer as an afterthought - plans didn't call for it. Hence, the short frames near the bow

Not sure what I am doing with the CC either butwill consider your advice when making it more permanant.

 

There are a lot of useful latches and so on available from Southco for this type of hatch.

 

thanks for the link - will look more closely at latch options once I have thing mocked up a bit.

 

Attached are two flush deck hatches for an aluminum boat.
Note that there are large hinges on these doors and are supported by gas cylinders to aid in opening.
The hinges are out of the way against walls and hard to trip over. I would not recommend a hinge set up for your boat (unless the hinges are also recessed) . Rather 4 of the recessed T-handle latches would be a better set up.

Under each joint is a channel that is about 2 inches wide by 1 to 1 1/2 inches deep that is scuppered out of the boat.

A more recent build that we did had 3 inch wide by 2 inch
deep channels as it was a much more open boat ( more like yours) and there was a possibility of a faster ingress of water so we wanted to shed it as quickly as possible.
If you have small channels and a lot of water, the channels can overflow the edges into the bilge rather than get it to the scuppers

 

Barry - I really appreciate the extra clarification, and pic. I agree that 4 of those locking handles would be best in my case. I have not placed nor cut my scupper holes yet, but I had planned on having them a bit more outboard of where the channel would run around the hatches. Do you think it may merit separate dedicated suppers for these channels and perhaps larger ones more outboard for the draining of the floor i.e water that sheds off main floor and does not fall in the channel?
If I were going with juts one set of scuppers at the corners of the hatch channel, I think it would work from the sense that a larger diameter hole would allow the channel to drain at the bottom and the main floor to drain up a couple of inches (where the scupper would be the widest). Of course, I would need to weld around the channel so no water could pass below to the bilge...

The rough drawing below shows what I mean, but it doesn't show channel running along the transom, which would have to be cut in to channel water out as well.

 

I just finished a couple hatches you guys might want to look at. Now I have to do a sliding hatch not quite sure what I'm going to do it there any ideas?

 

just an FYI

Often starts and stops with welds will leave a high point.
Pferd makes a Polifan curve which is similar to a flap disc but will radius an INSIDE filet extremely smooth

 

I probably would not worry about running extra channels down the side of the boat where the deck meets the side. The boat will never be horizontal either front to back or side to side. The water will move to the transom and out one side or the other.
So I would place scuppers in line with the channels for the hatches and a couple of scuppers in the corners.

That being said. If all of the channels are common with each other and the last channel is against the transom, as in the picture, you might as well run the channel to the edge of the side of the deck.

If all of the channels are common, you can run a single scupper. In the picture you will notice the holes where the transom door is. This is a single scupper for both of these large hatches as the channels were common.

You will also notice dirt in the stbd corner of the deck. (port as well) This corner did not have a channel to serve this corner and only when the boat was on land, we would get a small accumulation of water in the corner that would not drain. In the water, the corners would pretty much drain due to the movement of the boat.

Obviously, the scuppers must be as high above the waterline as possible so in a following sea or a fast stop, the water does not rush into the back of the boat. There is a 4 foot wide swim platform on this boat which minimized water coming over the platform and into this single scupper. The more scuppers, the more water that could get past them onto the deck

 

Barry - I was thinking that I would make up two fairly large access panels (as opposed to one very large one..) so that I could take either or both off for access to the middle of hull, aft of engine box.
As you can see in this pic, I even cut the aft middle section of the temporary wood floor in two pieces, for this purpose.

It would be nice to be able to lift either up, without having to lift off / tip the engine box, so I am thinking there would be a small, perhaps bolted on piece where the aft end of the engine box sits, and then two large access panels aft of this, with channel under sides and in between the two panels, all leading back to the scuppers.

Note - engine box in pic is only temporary... will be looking at forms / styles, methods later to build one out of aluminum, most likely having a few bends done by press brake to improve looks and reduce warping from long welds. Open to input..

 

Barry - I was thinking that I would make up two fairly large access panels (as opposed to one very large one..) so that I could take either or both off for access to the middle of hull, aft of engine box.
As you can see in this pic, I even cut the aft middle section of the temporary wood floor in two pieces, for this purpose.

It would be nice to be able to lift either up, without having to lift off / tip the engine box, so I am thinking there would be a small, perhaps bolted on piece where the aft end of the engine box sits, and then two large access panels aft of this, with channel under sides and in between the two panels, all leading back to the scuppers.

Note - the white engine box in pic is only temporary... will be looking at forms / styles, methods later to build one out of aluminum, most likely having a few bends done by press brake to improve looks and reduce warping from long welds. Open to input..
I would incorporate a few (recessed) drink holders, but the one in the other pic is one of the few I have seen.

 

Boat will be coming out for the season, in a week or so.

While it was in the water, at rest, I decided to put a level on the temporary floor panels to see if rain water would drain to aft scuppers, at rest, if I were to weld in aluminum sections, where the wood ones sit now.
Result - floor sections are pretty much level as is, and therefore I don't believe rainwater would run aft to scuppers, once installed.
My dad is a plumber..and I remember the old rule of 1/4" rise per foot needed for pipes/ drains....but I am hoping that I can get a way with less than that as even for the aft 20 ft of the boat, I think having an incline that rises 5" over the 20ft would be extreme...

So, what kind of rise do you think is common to achieve self-draining at rest?

 

An eighth inch per foot I think would be plenty. I'm trying to eliminate all the wood I can. Water pooling around wood will rot for sure metal not so much if painted or better yet aluminum