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Re: Double Eagle Build

Posted: Sat Apr 11, 2015 6:33 am
by Northeaster
Hi Kevin - I was just reviewing your box keel images from page 1 and had a couple of questions, if you have time to indulge me?

I will likely finish the outside keel seam weld this weekend, and then the outside chines soon as well.
I have read about testing welds having one person using soapy water on one side, while a second person holds an air hose along the other side of seam. Is this an acceptable method, or should I consider flipping the boat back over and putting a couple of inches of water in the inside (I imagine this would create less pressure than a boat floating / displacing water, but would it be better than teh air method?? I could rotate the boat so the chines were down oen at a time, and test them the same way as well....

I ask about testing for watertightness as I imagine the next step for me will be to start to mock upo the box keel (with large cardboard type sheets that came with aluminum sheet)?
In your drawings on page 1, the widest point of box keel is obviously wider than the 3"- 4" pipe shown, but wht would be your min / max recommendations for width, at the widest point?
As well, I get that you professionally build workboats for guys who use them alot and rely on them and thuus the focus on things like mechanical tube with the SS tapered bearing insert, precision tube machining, etc.
But, my plans just call for 2" schedule 80 pipe for the strut bearing holder and 1 3/4" OD tube for shaft log (min wall thickness 3/16"), as they show a cutout before prop, and therefore a separate strut.
I was thinking of using the 2" schd 80 pipe for a continuous shaft log/ bearing holder like you show, but simply pressing in the nylon type bearing in the end of the pipe, per the plans. The Id of the sched 80 pipe is juts under 2" and the OD of nylon bearing is 2" so it may take a bit of machining / honing to fit it.
I realize that this is not as good as teh way you do it, but this is a personal boat that will see less than a hundered hours a year. Is that a reasonable approach, following the specs on plans?

Re: Double Eagle Build

Posted: Sat Apr 11, 2015 2:20 pm
by kmorin
north, not sure where that 'weld test' idea came from but its short of reality. First, air used to test welds is used inside contained and sealed volumes not along seams open to the atmosphere ( :eyepop: what an idea!) as there is no way to (find leaks) develop pressure on one side of the weld unless they were just openings in the seam? Next, unless a test can be done (with pressurized air) at very controlled pressures and rates, the actual leak reveal is very questionable?

I've never heard of that open seam method so I can't remark beyond sensing that you were being put on by whatever you read on the subject of weld tests that involved open air jet seam testing (!) [Maybe you could just put the boat in the water and let it swell up?]

North, you may not have noticed this practice(?) but you're asking and answering your own questions? I am usually willing to take time to reply to posts where the reader at least shows some time taken to read what was posted. Unfortunate for this build, your decision (tree) methods are not sequential enough for me, or any experienced builder to help, that I can see?
Northeaster wrote:Is that a reasonable approach
What does reasonable mean? I think that word means different things to us, therefore what would seem to apply to me, may not to you, and vice-versa? For example, I've built lots of shaft drive boats, and know the cost of an out of aligned shaft, you have not and do not. What's reasonable- a cartoon shaft or an aligned shaft? To me, with the dozens or shaft repairs, and dozen new shafts: one or two ideas are fundamental and I've expressed them. To you, " 'close enough nail it' that'll be OK -right?"

Please don't ask me to ratify your lack of experience as a valid decision making basis for boat design. I can't. Most of the decisions you've shown in the boat are not adequate to my building standards and I cannot ratify/agree/support them. My experience is a reasonable teacher to me- somewhat harsh if my memory serves me at all? My experience may not be a valid basis for decisions to you and that is fine, I don't have anyway to reply, that is constructive, if you ask "is that reasonable" and then propose to rely on simply an extrusion's straightness for a shaft's alignment!!

When someone asks, you explain and they ask (again) "Say, would you explain?" there is a slight indication of disconnect, perhaps the concepts we were discussing are not well suited to online Forum exchanges? If you know, why ask?

Your habit of attempting to rationalize away the knowledge of others appears to me to prevent you from being able to learn so you could avoid errors in the build? (ie. stringers/longs; hull plating; assembly sequence; weld sequence; weld QA/practice .... keel design..) Just a quick review of each stage of advice (above) compared to your final (building) steps seems to confirm that you'll be happiest on your own when not confused by remarks or opinions from others.

good luck, with the build.

Kevin Morin
Kenai, AK

Re: Double Eagle Build

Posted: Sun Apr 12, 2015 6:49 am
by Northeaster
Hi Kevin,

I certainly understand and appreciate your point of view. Yes, perhaps my method of asking, and attempting to answer my own questions (in hopes that others will chime in with other options /pros, cons, etc) is not well suited to the internet forums.

Although it may not seem apparant, I have, however, taken alot of advice from you (and others) on many processes such as cleaning / prep work, welding techniques, settings, changing from plate to (hopefully) box keel, re-arranging stringers that you and others like Ad-Hoc found to be not in plane with the lines, building the Davis-jig, etc. I just have not taken all of your advice, nor that of anyone else, on all matters.

In your above posts you seam to indicate that any path I take other than the "professional" way (ie using stepped SS bearing holder vs sched 80 pipe) would not be worth considering. I think though, as the scheule 80 pipe, with no stepped bearling holder is what is called for in my plans, then I thing it is valid question to look for advice as to the cost/ benefit of each method. Of course, I do not want to ruin a shaft, but as mentioend my boat will see perhaps a hundred hours a year in personal use - so would the shaft begin to wear afer 10 hours or 1000 hours, if not put in to your standards... I am not in any way saying your standards are unreasonable, but only that if I got 10 years from a boat before suffering some wear and perhaps re-working things, my decsision may be different that if i were told i would see issues arise within the first couple of years.

I do have a good sense of humour, so I don't mind you poking fun of me, with comments like perhaps floating the boat would test the watertightness.... Yes, I get it, and i even have a small lake nearby, but it would still be difficult (at this stage) to get the boat (with jig attached as not finished yet) and no trailer down and in the water. I too question the effectiveness of the air wand/ soapy water method I described, but I can assure you that it was not someone pulling my leg... it came stright out of one of my resource books( I think either Pollard's book or the Glen L book that comes with the plans).
Perhaps I am out to lunch, but the reason I would like to check my keel seam and chine seam now are that I would assume it would be better to find and fix any leaks now before a box keel is welded overtop / around the keel seam and angle lengths are welded ontop of the chines....... So, I think it is a legitimate question to ask the best way to do this, bringing in the couple of methods I have read about and looking for advice, pros/cons and other options (floating the boat being an excellent one, just difficult at this stage with the above challenges and the foot of ice in the lake....)

It's too bad that the Glen-L metal boat forum is not busier, as I know my questions are likley more suited to other amateurs (who have more experience than me) but who were still happy with thier home-built boats, built to solid, albeit not professional standards.

If you choose not to continue to read this or contribute, I respect that decision, but I do want to thank you for taking the time to post here, and on many other forums, as I have learned alot from you in reading posts on a variety of subjects.