Progress pics and questions on Aluminum Double Eagle build

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Bill Edmundson
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby Bill Edmundson » Sat Jul 30, 2016 11:34 am

I'm running a 125 Metric HP Yanmar. WOT under load is 3900 rpm. The tech. told me to take it out of gear and find its MAX! At 5500 rpm I chickened out! I asked him about break-in. He just said don't worry about it. Just go for it. I do make sure it has been at full operating temp before I open it up.

Bill
Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

North
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby North » Sat Jul 30, 2016 4:36 pm

Wow. I am used to the 15 HP 34 year old Yanmar 2gm in my sailboat. It tops out around 3200rpm. I didn't know that even the new ones would Rev at say 5000rpms.

Ken - great.info. I hopefully will check tomorrow. Should have time to install larger expansion tank, better plumbing and the new to me diesel tanks tomorrow.

Psyco-. Thanks for the encouragement. Will try to get a better hole shot video tomorrow.

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Bill Edmundson
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby Bill Edmundson » Sat Jul 30, 2016 4:41 pm

North

I had a 1GM in a sailboat. It sounded like the African Queen. Great little engine though.

Bill
Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

North
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby North » Wed Aug 03, 2016 3:17 pm

I don't know if this video is much different or any better than the last, but I tried to capture a quicker hole shot.... by myslef, it was hard to hold the wheel, throttle, camera and hang on...no real seat yet - just leaning against a loose temporary engine box...

https://www.youtube.com/watch?v=BN9DheHXZbU
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On our dock

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kens
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby kens » Fri Aug 12, 2016 6:47 pm

Long time no new post,
How's it going?
Oak is over rated, everything about it takes extra time; then it warps, splits or checks !!! :roll:

North
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby North » Sat Aug 13, 2016 5:12 am

Hi Ken,

The boat is coming along - now have one permanent below deck SS fuel tank connected (no more jerry can..) and new proper gear driven sea water pump is working well - now cooling engine well at all speeds and feeding the DIY wet exhaust "elbow" I made from SS pipe - and proper 4" wet exhaust hose.
it is not really an elbow as I just made a straight water injection piece and then brazed on the existing short dry elbow - but it works well and costs maybe $60 in pipe.
I still haven't got a video shot from outside the boat - want to do this soon, as I would like to see how it sits/ rides at various speeds and get your opinions on placement of larger permanent fuel tank, battery ,etc this winter, depending on how it looks...

with wet exhaust hose only (no mufflers) it is a bit loud, especially at higher rpms, so this winter I will look into buying, or making some sort of muffler. Prices are a bit high for mufflers when you get into the 4" range, and I can't imagine it would be too hard to make one out of aluminum or SS if I get a drawing of their guts / how they work....

Had it out in 3-4 ft chop and 25 kt winds a few days ago and it worked well - pounded a bit too much at full speed of course, but at around 15 - 18 kts it was still very tolerable.... still very impressed with how it works!
23 kts top speed and 4.5 - 5kts at idle.
still working (not hard) on a couple of electrical / gauge issues"
1. tach works up to about 2800rpm and then goes down to zero (both in neutral and gear)
2. oil pressure gauge pins out (from power and/or ground lead issue) even when not running, with key on.
3. 1 wire alternator (GM style I believe) not charging - I tried exiting it per youtube videos by crossing hot/ batter lead to (unused) #1 spade terminal connection but it did not make a difference.

I should be working on these issues harder, but to be honest, with 2 young kids (who aren't allowed on the unfinished boat yet), when I get an hour or so free I just take it out for a run and charge the battery later t enjoy it...rather than work on it much right now.

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kens
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby kens » Sat Aug 13, 2016 6:01 am

Sounds really great.
As light as you are right now, no cabin and not fully completed, you should be as fast top end as you'll ever see.
I think you got a few knots missing somewhere. You say 23kts, i think you should be 27 running this light.
Did you find your high idle engine speed?

You said you were in 3-4 ft chop, chop or what I call a confused sea, is the absolutely worst to run in.
I was out one day the swells were all running same way, at about 6-7ft, and I was trolling 4 lines and kicking back with a cool one waiting for a bite.
But then a 4ft chop (confused sea state) will beat up a 36' charter boat.
Oak is over rated, everything about it takes extra time; then it warps, splits or checks !!! :roll:

North
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby North » Sat Aug 13, 2016 7:22 am

I see. Here, by chop we just usually refer to short quick waves. Short timeframe between as opposed to those from longer swells. These were all from same direction. I do know what you mean though by a confused sea.

Have not found my high idle due to tach issues mentioned.
Sometimes tach goes back to zero after about 2200rpms but at other times goes to about 2800 before gauge goes down. At this point I still have some throttle left and I think I get about 200 or so more rpms

I would like to find high idle, and see what that tells us. But, frankly, I am pretty happy with this speed range and I think I would be just as likely to adversely affect performance, if I play with pitch at this point.
If I were only getting 15 kts top speed, or showed signs of severe over or underpropping, I would for sure be looking to get closer to optimal.

If you look at the DE build notes / specs. I think it is my full keel that is keeping me from higher speeds at top end rather than a prop / pitch issue. Just my thoughts though.

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Bill Edmundson
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby Bill Edmundson » Sat Aug 13, 2016 7:55 am

North

I know what Ken is talking about with confused seas. In Mobile Bay Alabama, if there is a lot of water coming down the river (N-S) and the tide is coming in (S-N) and there is a good wind out of the east or west, then there may be no pattern to the waves.

Bill
Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

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kens
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby kens » Fri Aug 19, 2016 6:41 am

How does she handle with that keel?
Does she heel in the turns?
Does she prop walk in reverse?
Oak is over rated, everything about it takes extra time; then it warps, splits or checks !!! :roll:

North
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby North » Sun Aug 21, 2016 4:03 pm

I think it handle well with the keel. Tracks well. Goes straight when you take you hand off the wheel.
Only heels slightly in turns. Just enough to let you know you are turning. Some would likely think it is too on the safe side and sacrifices some fun, but I still think it is fun to turn. You can do a full cut of the wheel at 20 kts and not feel like she will skid or anything.
Only a bit of propwalk in reverse. Reverses quickly but as expected no real control. In tight quart errs I would just use reverse to stop then give alternating shots of fwd and Rev with the wheel cut hard so it turns mostly in fwd thrusts and then stop / stays put with the reverse shots.

North
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby North » Sat Apr 08, 2017 6:03 pm

Finally started working on the boat, with only about 6 to 8 weeks till launch again.
Used boat last summer without finished gunwales -. Only had aft sections of pipe covering topsides - nothing up towards the bow. Heated pipe and bent to fit today. A fab shop with rollers would have made smoother bends but it's good enough for me.

Will add 5 inch flatbar inboard and on top of pipe and then finish with another pipe on inboard edge of flatbar. Bending flatbar to fit by cutting relief cuts every 3 inches where curved and tacking back together.
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North
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby North » Sat Apr 29, 2017 3:02 pm

Back at it today, working on gunwhales. Added flatbar and pipe to starboard side and working on flatbar on port side.
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BillyZ
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homemade surface drive unit

Postby BillyZ » Sat May 06, 2017 8:48 am

North wrote:Hi Billy -Better late than never!! Just joking, but I am really excited to hear from someone who has built the same (albeit heavily modifed) boat in aluminum. I have received alot of great advice here, but not alot of info specific to an aluminum build.
Sorry to hear about your accident - A year is along time - I tore a bicep about 3 months ago, and was sidelined for at least 2 months, which was painful enough - anyway - hope you can pick up the tools soon!
Also hope you stop by this forum somewhat regularly - I am sure I will have questions - just in case, I will throw a few at you now if you don't mind.....

I am using 3/16" 5083 h116 on hull.

1.. What alloy did you use on the hull?

2. welding - I am only a hacker, but improving nicely. Just did 3' butt welds, on shop floor, all in one continous pass per side, as opposed to short 2" or 3" welds, which is often recommended for aluminum. Not sure if I will be able to do this on hull, after tacking whole thing togther. What length welds did you do on butt welds, keel and chines, following a pattern I would assume?

3. keel - do you have any keel under there and would you change anything if you did it again?

4. Your surface drive vs a standard shaft drive inboard. Mine will be protected and unprotected Atlantic ocean use. Even if I do the regular inboard shaft drive, I will likley build a box keel rather than the single plate keel in the plans (based on advice fro man experienced aluminum builder/ repairer). This may be full depth and house the shaft tube/ bearing or considering a shorter keel like the outboard version, but would then need a strut and supports for the bearing, similar to plans. I really like the idea of having the running gear / shaft exit the transom like you, but have no experience with any surface drives. My conditions / normal wind and chop, I think would mean that I run around 12- 15kts more frequently than 20-22kts, but I could be wrong. I have read that surface drive gains are usually on the top end, so do you thinks that your setup would be right for me, or what's your thoughts?

5. Transmission - what reduction ratio is your's, in case I go the surface drive route? I now have a 1:1, but I had a 2.91:1 and sold it. I do have a 2:1 available at a decent price. My cummins 4Bt is 150hp.

6. more welding - just bought a Miller optima pulse pendant, to go with my XMT 304 and push pull guns - did you use pulse mig any, or do you think it will benefit? I have not turned boat yet, but I built a rotating jig out of heavy steel, so I should be able to turn it, to do inside welds, and then flip back for outside welds, etc.

7. Fitting hull sections and topsides - did you make patterns/ templates out of roofing paper, cheap plywood or similar? After rough cutting sections, did you juts put them in place, and continue shaving off a bit at a time until they fit? With what tools, jig or circ saw, router, etc.. did you find the best. I have used all including a hand power planer, but I have been busting the small carbide blades.

8. sheer line near bow- really likes the look of your raised sheer fro mabout midhips to bow, so I did the same, when cutting my topside patterns - just too a stab at it, and tried to have a nice line - one topside is rough cut in aluminum now...- any tips?

I'll leave it at that for now, but would really appreciate any futher info and help! My father in-law is helping me - we both like messing with stuff and he is good at figuring mechanical things out - had heavy equipment for 30 years and did most work himself. I don't care if it runs perfect right away - just want to get it splashed, use it some, and then put it back in the shop after, or the following winter, if we want to really change or add anything - like a small cabin or a CC like yours - wil ljuts start very basic for now likley.

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BillyZ
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Re: Progress pics and questions on Aluminum Double Eagle build

Postby BillyZ » Sat May 06, 2017 9:22 am

Had a back operation and out of everything for a while that's why this post is 2 years late. anyway I have made 3 fixed shaft surface drives, the last one on my Double Eagle. With that engine and horsepower I ended up putting a contoured piece of 3/8" aluminum- 2' wide x 4' long ( V'd to hull vee at leading edge to a 26" arc or so trailing edge to contour prop shape). Pretty cool how that shape forms in a home made press. Without something to deflect the reverse prop wash under the hull, it will push the hull forward in reverse, faster then you think, did we laugh at the doc that day( took a real ribbin' I did). It also had 4 or 6" side panels to keep from sucking air from the sides. Turned into a prop pocket under the swim platform. Drive unit is bullet proof. A commercial guy bought it and said it ran everyday for the 1st year without a problem. I have talked to him recently and he said he went through a dozen or so props (no shafts), he makes jetty's and all kind of stuff on the Chesapeake Bay and is always in shallow water and pushes a barge full of jetty rocks. He told me the hull is bulletproof. Cool to hear while laying on your back. Couldn't watch him cut off the bow pulpit with a saw !!! Would I build that unit again....absolutely. Easy to trailer, strong short shaft, regular packing glad, low maintenance, handled well in 4-6' seas, will take abuse and ask for more. My cruise speed was around 14 knots, 18 wide open. A little faster in the fresh/brackish water in the Chesapeake, boat sits a little lower in fresh water. The only change I can think of would be a fishtail rudder or one that articulates. If I ever get the chance to make another Double Eagle, it would be something with a cabin and bunks to cruise to Florida and back. Maybe with a 4 cyl cummins because the hull moved so nice in the 4 to 9 knot range. What a boat!!!
Billy Z.


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