Boat Builder Central - Builder Forums

I finished painting my HM19 yesterday - after 21 months of work. I have put some pictures in my Builders Gallery. When I rolled the boat out of the garage all the neighborhood kids swarmed. Here is a picture:

I modified the sides of the pilot house - making it more open. Per Jacques direction I left 3" of plywood on all sides of the opening.

Ralph

Wow I wish you were MY Uncle Ralph! The boat turned out great!

Nice, really nice! How long till splash? You should be proud, she looks great.

Man - she sure is the show boat for the HM19! Looks better than on the study plans. I like the way you did the brightwork. Great job!

Very nice! Can't wait to see it in the water.

Beautiful boat. Love the open pilot house.

I've pretty much finished the dash on my HM19, except I'm waiting for two gauges for the empty holes. Nothing is wired yet - will start on that now.



The sunlight in the background made the picture a little dark.

Ralph

Ralph,
Nice going, and the kids give a perspective to the size of the boat. Yes the bright details looks very special.

It looks like one of those trick pictures. How many kids are in the picture? The first time I looked I saw three, then another then another…I see 6 people on or in the boat. Am I right?

If that kid at the back can kick hard you may not need get a motor.

Scott

Fantastic! I wish I had the room and the time to build a fleet of boats. I'm glad I at least get to see what others are producing. Can't wait to see it on the water.

jason

I see 6 kids. Wow!!

I finally completed my Harbor Master 19. I now need to get a motor. I will also get canvas enclosures for the sides and back. Here is a picture of it being loaded on the trailer for the first time.



Ralph

UncleRalph wrote:I finally completed my Harbor Master 19. I now need to get a motor. I will also get canvas enclosures for the sides and back. Here is a picture of it being loaded on the trailer for the first time.

Sweet boat! More pictures! More, more!

Great boat. Can't wait to see you with it on the water.

I caught my very first snook on my boat this last weekend. (That's the first one ever in my life.) 7 pounds.

Looking forward to hearing about your experiences.

Beautiful boat UR! When are we going to see it in the water?

Superb job, she looks great.

Fine looking boat Ralph! You did an exellent job!

WOW - I'm speechless! She is absolutely stunning. Heck, the renderings of the HM19 don't even look close. That boat looks WAAAAAAAY better built by someone like yourself!

..and yes: More photos please! Of everything. Every nook, cranny and gadget you have on there! Close-ups to please!

Congratulations!

Wonderful job! I hope you enjoy it in the water soon!

Congratulations!!

She is absolutely beautiful! Superb job. Many congratulations.

JG

Brightened up that dash picture for you a little. I wanted to see your fine work and thought others would want to as well.



The boat looks awesome Ralph!

That spray rail really adds some character I think.

very, very nice

Joel

Thanks for the compliments everyone. The boat is at the canvas shop now and then goes to boat dealer to get the motor installed (Honda 50). I will take some more pictures when I get it back. I hope to get it in the water a couple of times yet this year if the weather cooperates.

Ralph

U.R. , What can I say, so I'll repeat "speachless" about covers it.

Ive always loved the Novi look and your boat nails it.

Be very proud, that was whale of a project!

Now I've got to get past the little mundane things in life, ( like making a living) and get back to My OD.

Please keep us posted, I can't wait to hear how she acts on the water!

Bill

She is beautiful! What a nice finish. It GLEAMS!

You will be bursting with pride when you take her out. I predict much fun will be had aboard that beauty. Keep getting pictures and let Jacques use them. Good pictures of boats built that well are worth their weight in .... ?

Outstanding and very inspiring! We can't wait to see it in the water. More pics please...

Kent

Splashed my HM19 today!


I don't have any pictures in motion. I reached 20 knots (23 mph) at 6200 rpm. The motor is a 50 hp Honda.

Ralph

That's inspiring. Hope you get a chance to post some interior pics and in-motion pics.

-Dave

Dave,

It may be awhile for some in-motion pics. I lucked out with the weather today, but the season is about over here in Maryland.

Here are some interior pics:

A view looking into the pilothouse.



Here is the cabin showing the v-berth. A Porta-Potti will be installed under the center portion.



Looking aft at the cockpit. The rear quarter seats have folding legs and become the v-berth filler pieces.



This shows the electrical wiring on the back of the dash. I plan on making a box to enclose it.



The last picture shows the canvas enclosure I had made.



Ralph

Where did you get the windshields ? The boat looks great.

Fantastic piece of work. Very inspiring. I'm sure Bateau will grab a shot of this for their promos. Very well done.

Regards John H

WoW.

I think I've said it before but I wish you were MY UncleRalph

No kidding! Truly a beautiful boat and amazing workmanship and attention to detail! Congratulations!

She's a beauty! Really! It was this kind of beautifull workmanship that made me think of building my own boat. Trully inspiring.

Congratulations!

She is a real beauty!! Great job!!!

Chris
OD18

Concur with everyone, great looking boat!! I too am curious where you got your front windows.

Great job Ralph!

Isn't splash day fun, .... and nerve wracking.

The nerve wracking goes away but the fun part stays around.

Beautiful boat!

Very nice

Yoda wrote:Where did you get the windshields ?

I got them from Wynne Enterprises at http://www.wynneinc.com/.

I sent them a template and they made the windshields to fit. BUT, I should add that these are not per the plans and not recommended by Jacques. He has said he is opposed to the extra weight added with framed glass windshields on this boat. In my case about half of the extra weight I added was offset by the weight reduction from opening up the sides of pilothouse - instead of having wood sides with a small window, I removed all the wood except a 3" frame around the outside. At least that was the justification in my mind for adding the windshields.

Ralph

This is a yacth!! Congratulations!!

All I can do is agree with all of the above, BEAUTIFUL!!!

How did she behave herself on the water?

Great Job!

Bill

A+++++ for Uncle Ralph. Fantastic job.

THanks for all the compliments guys.

odras wrote:How did she behave herself on the water?

I need to qualify my answer with the fact that this is the first power boat I have owned. I have driven a few power boats, but never owned one. It seemed to handle quite well. I had hoped for a couple of more mph's, but it is a brand new motor. There did not seem to be a very abrupt transition from displacement to planing - it just seemed to gradually pick up speed. The water was pretty calm, maybe a 4-6 inch chop. A couple of times crossing the wake of other boats, the prop seemed to cavitate. I don't know if this is normal or not. The cavitation plate is set up almost exactly at the bottom of the hull.

Ralph

UncleRalph wrote:I had hoped for a couple of more mph's, but it is a brand new motor. There did not seem to be a very abrupt transition from displacement to planing - it just seemed to gradually pick up speed.

Ralph, you are this close to experimenting with your prop. I've seen this before...

Beautiful boat! Congratulations!

Quite strange with the performance. What pitch is the propeller?

You are running the engine a bit too high revs, not much though. The engine would be happier with little lower rpm's.

There seems to be some oddities - like the fact that it sounds the prop is getting air in waves. Also the speed numbers indicate that the prop slips more than it should - prop might get little air all the time. you could try to install the motor lower, the boat's skeg might change the ideal motor depth. Try different trims on engine - maybe it's trying to push bow too deep now.

If you think all is running well, then you could try a prop with 2" more pitch. But I would test a bit more with your current prop.

Ralph,

Back in October on this same thread, you mention you took it to the boat shop to have the motor installed. Did they set the motor up for you with regard to the prop, pitch skeg etc.? Or did they just mount it on and wish you luck? I would have thought that they should have had some experience at judging the best set up for your boat and the Honda.

Regards
John H

I would agree with Tony, look at the pitch of the prop. I do not like my engine to turn more than 5800-6000 RPM. I would consider re-pitching the prop to avoid exceeding 6000 RPM. It will give it more bite and though you may not accelerate (hole shot) as quickly you should see a better top end speed. Blake

Thanks for all the prop advice. The dealer that installed the motor did put it in the water to test the prop. They told me it maxed out at 5800 rpm. I am not exactly sure how I got it to 6200 rpm. The Owners Manual says maximum should be 5500 - 6000. I probably will try a different pitch in the spring (the current prop is a 13 inch pitch). Unfortunately the motor is as low as it can go without cutting down the transom - not something I want to try just yet.

The skeg may be having an effect, although it is pretty small, about 3/4" by 3/4". In a thread not to long ago I think Jacques said he didn't think a small skeg should have much impact at slower speeds, meaning, I think, less than 35 or 40 mph.

For all you knowledgeable prop guys - what effect does switching from aluminum to stainless steel have?

If you get 6200 rpm (too much), it indicates that you could use more pitch.
13" pitch isn't much. Looks more like a pontoon boat prop. What's the diameter?
You can also cup the prop but I would try more pitch.
An SS prop will give you sligthly better performance at equal rpm because it doesn't flex but I think you don't have enough pitch.
PS: I am not an outboard expert. I can calculate a basic outboard prop but I am not as knowledgeable as some of our builders. Correct me if am wrong. about the pitch.

jacquesmm wrote:If you get 6200 rpm (too much), it indicates that you could use more pitch.
13" pitch isn't much. Looks more like a pontoon boat prop. What's the diameter?

The diameter is 11-1/8". It is one of Honda's standard props.

I'm going to try to take it out again in the next few days. If I still get 6200 rpm I will take the prop back to the dealer and see if I can exchange it for one with more pitch.

Ralph

I thought about 13" pitch.

So, let's calculate; 6200 rpm (engine), gear ratio 2,08 (from Honda's website), 13" pitch.

The calculation gives 36,7 mph speed. (6200rpm/2,08*13 inch=38750 inch/min= 36,7 mph). In reality the propeller will slip in the water and the speed will be lower than calculated there. The slip in this case would be 37% (because you measured 23 mph). And this figure is not what usual planing boat should have. Most planing boats have slip around 5-15%. Like couple people here in the forum has had 7-8% slip which is very typical. The high slip value is what I'm wondering about. Of course it can be okay, it's just more than I've seen in the some cases I've been studying. That's why I would try some different setups trim angles etc. to make sure the prop is not getting air.

Also did you check the speed measurement?

If all is right the and you'll change to different propeller (assuming same slip and speed)
14" will give 5750 rpm
15" will give 5400 rpm.

Note that as the rpm's drop the motor will generate more power (max power at 5750 rpm), so 14" should give slightly higher speed and rpm's as mentioned above.

The Honda engine is running quite high rpm's naturally. But if you can change the prop select atleast 14" most likely the 15" would be best (atleast if you don't run occasionally with heavy loads).

You could cup the propeller too, it might get better. But I guess it's easier to change the prop if you can do it without charge.

Toni V wrote:I thought about 13" pitch.

So, let's calculate; 6200 rpm (engine), gear ratio 2,08 (from Honda's website), 13" pitch.

The calculation gives 36,7 mph speed. (6200rpm/2,08*13 inch=38750 inch/min= 36,7 mph). In reality the propeller will slip in the water and the speed will be lower than calculated there. The slip in this case would be 37% (because you measured 23 mph). And this figure is not what usual planing boat should have. Most planing boats have slip around 5-15%. Like couple people here in the forum has had 7-8% slip which is very typical. The high slip value is what I'm wondering about. Of course it can be okay, it's just more than I've seen in the some cases I've been studying. That's why I would try some different setups trim angles etc. to make sure the prop is not getting air.

Also did you check the speed measurement?

I follow your calculation, but I don't think this boat would ever get anywhere near 36.7 mph with 50 hp. In the study plans Jacques estimates 24-28 mph depending on load based on the Crouch formula- so I am not that far off at 23 mph.

What would cause there to be excessive slip?

A couple of clarifications:
1. The speed was measured by GPS. I think it is correct, but don't have anything to compare it to.
2. There was about 650 lbs. of load, including people, gear and gas.
3. I don't know what the boat itself weighs.

Thanks for your help. There is definately a wealth of knowledge on this board.

Ralph

I follow your calculation, but I don't think this boat would ever get anywhere near 36.7 mph with 50 hp. In the study plans Jacques estimates 24-28 mph depending on load based on the Crouch formula- so I am not that far off at 23 mph.

Just to clarify: no boat can go at the calc speed as above. There will always be slip - the speed difference is what pushes the boat forward.

And then there's over revving in waves, which is telling you that the engine does get air a bit too easily. Excess air would lead to more slip. I just linked these informations together...

On a second thought the prop diameter does seem quite small... Maybe such a slip is okay for boat like that. It's just more than I've seen in planing boats. Though I've done the calculations mostly non-cabin (quite light) boats...

GPS speed should be good.

As I got the impression that you haven't been boating so much so you should try some basics; Try to trim the engine up or down and monitor the gps. Also you could try to move load (or people) to bow or stern to see if that helps.

If you then think it's running nicely - try 14 or 15 inch pitch prop... You'll get couple mph's with those. 15" pitch will be better in fuel economy, 14" pitch will get the boat easier to plane with load.

Don't worry about the slip too much, the slip itself doesn't matter so much.

Toni V wrote:As I got the impression that you haven't been boating so much so you should try some basics; Try to trim the engine up or down and monitor the gps. Also you could try to move load (or people) to bow or stern to see if that helps.

You've got that right. I have had sailboats for 20+ years, but this my first power boat - so this part is all new. Also, I have only had the boat on the water for about three hours one afternoon, and I probably spent most of that time just basking in the glow of my newly launched boat.

More detailed experimentation to come.

Ralph

In very general terms, the bigger and heavier the boat the more slip you will have with a given hp and prop.

Paul

After reading all the prop talk I want to share a little.
Speed and pitch / Alum vs Steel:
My C19 did about what Jacques' formula said it would with a stock aluminum prop. A cupped and raked stainless prop with less pitch kept the same RPM (cup and rake lowers RPM too) and raised top speed by 5 mph! I like the stilletto prop.
Cavitation:
My aluminum props didn't do well when trimmed up much at all, ... they started to cavitate at about half trim. The stainless stilletto trims all the way up and stays hooked up all the way up! That's where the speed increase came from.
On my D15 I had some cavitation from the skeg being too close to the motor. the only solution was to cut off the skeg trailing edge and taper it some. Cavitation went away then. Hope this helps.

Do I remember right that the rake is used to reduce cavitation? It's supposed to shed off the air.

Best would be to test different propellers, some just work better for different cases. Stiletto's are good in some cases, but not in every case.

Working the skeg might be good, just don't overdo it.

With a Bass Boat the cup in a stainless prop allows bow lift. So the prop actually grabs better. I think the rpm's are the likley culprit if the motor height is correct. I run the 175 HP Johnson very high on the transom. If I trim out too quickly while getting up on plane the prop will blow out. The prop is pushing too hard for the depth. Once up I can trim all the way out and pick up 1500 rpm's. Doesn't the Honda dealer have props you can try?

Toni V wrote: Just to clarify: no boat can go at the calc speed as above. There will always be slip - the speed difference is what pushes the boat forward.

I take prop slip in account in my formula. I call it the Crouch formula because that is the name of the naval architect who published it but I use my own factors and they include slip.
On the other hand, you are correct that a formula based on pitch and rpm without slip is too theroritical.

Another factor in my formula is weigth and UncleRalph's boat is very nice but may be a little heavy.
However, I still think that if he reaches that rpm so easily, it means he can increase the pitch. Plus, it's a new engine, still tight. Within 20 hours he will get more torque out of it.
I remember how we did at Cigarette. We calculated a theoritical speed with slip etc. with software from Rollo and rigged the boat with those props. Then we ran real tests (lost of fun!) and fine tuned the prop type.
We always got at least another 5 mph out of the boat.
I believe UncleRalph will get to 28 mph with more prop and after 20 hours.

I want to again thank everyone for the useful prop education. I just wanted to make sure it was clear that I am NOT disappointed in the performance. I only had the boat on the water breifly and someone here asked for my first impressions - which I gave. It is not the case like someone earlier on this board that was pretty unhappy with their performance when the splashed their boat. I am satisfied with what it has done so far and I sure with more experimentation (and a broken in motor) the performance will be right where it was predicted and where I had hoped.

Ralph

We understand you are happy with the boat: who wouldn't, it looks absolutely great.

Jacques;

I take prop slip in account in my formula.

Just to clarify more.... Slip has no effect on speed. Propeller efficiency does have the effect.

For example a 50hp outboard: The fuel gives 200 hp, engine gives 60hp, propeller shaft gives 50hp and optimum propeller pushes to boat forward by 40 hp or poorly fit prop gives 25hp power. All that wasted power ...

But let's get back to the slip. So what I'm talking about is that theoretically slip and efficiency are totally different. But in most real world cases the excess slip in planing boats will reduce efficiency.

And Jacques is right about the new engine. Especially as it's been running on too high revs and new motor does not do it eagerly.

If you want better performance you have two choices - try to get the prop slip less or use propeller with more pitch. Both ways gives you less rpm's and more speed.

And the best thing - don't worry too much, enjoy your boat

Uncle,

We just want all the spectators to be scratchin' their head and wondering how a little 50 could ever be pushing that tank around at that speed, " ....is it twins?" I remember a casual observer thought my boat might do 25 or so with that 115. You should have seen his jaw drop when I told him the tank did 46+.



It is very clear that you are happy, but we are all fiddlers and feel the need to help you fiddle with it. We don't know each other but if we saw each others' boats we'd say "hey, there goes my buddy's boat."

It is very clear that you are happy, but we are all fiddlers and feel the need to help you fiddle with it. We don't know each other but if we saw each others' boats we'd say "hey, there goes my buddy's boat."

You got it right there Jim......

Ingat ka

John H

This is my HM19, "Miss Anne", at the Mid-Atlantic Small Craft Festival at the Chesapeake Bay Maritime Museum in St. Michaels, MD last weekend. It won second place in its category - contemporary design built with modern materials. I was suprised it won something because it is not the normal kind of boat people bring to this event. In fact out of over 120 boats it was only one of two power boats. Most the boats at this event are small traditional sail or rowing boats.


Ralph

Uncle Ralph,

Where did you get those front windows??? I really like that concept, to get the breeze going.

Thanks Jody

Congrats on the second place finish.

Sure is one nice looking boat.

Copro wrote:Where did you get those front windows??? I really like that concept, to get the breeze going.

From Wynne Enterprises at http://www.wynneinc.com/

They weren't cheap, but were less expensive than other companies that make custom made windows. I sent them a template of the window cutout and they made the windows to fit.

Ralph

Ralph, a well earned award I would say. Congratulations on a not suprising outcome. Your HM19 is one of the best looking home builts I've ever seen. And to JM too, for the design. Hip hip..............

I've seen pics of your boat before, but this one really shows it off -- nice, Ralph!

Is that a sharpie schooner in the background? Another sweet boat! My wife refers to this sort of thing as "boat porn."

Rick wrote:Is that a sharpie schooner in the background? Another sweet boat! My wife refers to this sort of thing as "boat porn."

It is a very nice version of Commodore Ralph Monroe's Egret. Definately a sharpie, but I think it is a ketch not a schooner.

Ralph

No surprise at all. Congratulations! I've been waiting for some "action shots" of your boat. She looks very confident on the water. More action shots if you've got 'em.

Congratulations UR. I suspect you could win many similar awards at shows.

I second the request for additional photos if you have them.

arghhh! double post.

Congratulations from me, also Excellent work.


Rick wrote:
Is that a sharpie schooner in the background? Another sweet boat! My wife refers to this sort of thing as "boat porn."

I think that is a cat ketch rigged sharpie. Definately boat porn.

Looks great!!, love those seats!

I love this boat! You did a terrific job building it, quite inspiring. Congratulations!