Learing inboards

I am stuck at a point where I need to optimise a frame along the hull drawing. The smaller I can get this frame, the easier the lines are to draw and fair with the auto spline function to come up with a feasible craft that will have a power to weight ratio that is in favor of a 30 knot cruise

I can't get my head around the resistance to working out some options that will physically fit, makes the entire exercise meaningless and I am out of this discussion as I do not log on for these kinds of interaction. There are plenty of pleasurable things to be doing instead and I'll take more of a 'suck it and see approach' and maybe I'll get there that way

 

Sorry, but you have lost me (again) - can you post a sketch or a photo of how this frame is currently arranged?
As the saying goes, 'a picture is worth a thousand words'.

It is all very well making the frame smaller, but will it be strong enough?

 

This is the frame nesting. It makes one wall of the engine bay, 3mm aluminium sheet material. This frame is the bottleneck as to the overall cross-section in the freeware programs drawing ability.

bh

Its dimensions are very important as it will dictate my ability to create a drawing that will accommodate using a 4'ish butterfly jigging outfit over the side

A small dimensional change here yields a greater change to the overall surface area of the craft and thus the overall weight. Correct me if this is wrong, going smaller here will result in a stiffer surface as all surfaces will be smaller while material thickness stays 3mm

So three reasons for preferring a smaller frame here, programs drawing ability, usability and decreasing overall weight/surface area

Anyway, it doesn't really matter, as its all only part of a greater thinking and learning exercise and a distraction and the tone of the reception leaves a bad taste in the mouth

 

Just found that I can drop up to 30cm off the width and height off that frame and still comfortably fit a bmw 1200cc motorcycle engine in there. That would be the biggest displacement engine I would consider so it makes for significant tuning of the lines of the craft. The whole lot of the engine life support items can be left intact including the handle bars. The space frame extending past the engine can be cut off. Front fork taken off and handle bars mated to push pull steering cable

 

There was a very inventive designer and builder who developed several out of the box cutting edge game changing technologies between 1970 and 2010. One in gear type, one in hull form and one in processing. Estimated he made and lost tens of millions over 3 cycles. One of the buyers of his technology gave him a router cut plaque that read " mediocre solutions to obscure problems".

It's a tough cross section, I've been in the marine trades since childhood and read this forum since college age. While some are opinionated and even wrong from time to time, it's a fool's errand to discount all due to a thin dermal layer.

When reinventing the wheel it's best to mitigate the unknown. An established power plant helps benchmark if a hull is actually a benefit or not. Would it not be terrible to do all this work and fail from a design flaw solved by an off the shelf part.

Second, many of us are trying to give constructive criticism from a life of either failing or watching a lot of failing. Offsetting the dreamer bookend with the downer bookend of the reality of what many of us learned the hard way. Like the old man mentioned in the first line, keep the skin thick, test each thought objectively to see if it has merit, you might pull off something innovative.

 

It's about choosing to spend my day interacting in a place, where some find the highlight of their day is getting personal and unpleasant. I do not wish to read that kind of rubbish. Every time I browse the thread to go back to whatever particular bit I need to look into, I keep re-encountering that drivel. I started a new thread to get away from all that nasty toned stuff and up front ask him to refrain from keeping the personal criticism out of it, but the bwoy doesn't even have the ability to take a hint. I have requested the mod to somehow tone that nastiness from that direction down, but without any joy

Interacting like this is not my style. My folks brought me up to communicate with a lot more sophistication and style, including the necessity of personal digs at people that I do not personally know

This thread is unpleasant to reread. In the new thread, I will post a query for you. Maybe you can steer me in the directions that might help me find some answers

Thanks and regards
Randy

 

Saqua, have you even bothered to read my post? I gave you a host of options from 100 to well over 300hp, from really light to barely under 200kg, from cheap to expensive, from marine engine to easily marinized to difficult marinisation, from carburator to GDI turbo.

Please define your needs further, how much power do you want, how much are you willing to spend, how difficult is a custom transmission. There is a significant gap between the 13B at 250hp and the BMW 1200 at 136hp, so what is really important for you? Price, weight, availability, easy to marinise, etc.

 

Rumars, I looked up all the engines that you listed. I had a hard time finding resellers for some. I looked into some of the related engines as well like the L16. Its really hard to find the information on dimensions and weights online too. The most attractive are the rotax options and I then I came across more options from rotax in the 4 stroke engines too. Problem is very limited information on those too

100hp plus
Fit inside a 1m dia tubular engine bay
Less then 200kg for complete engine package (hoping that the stock cooling system from the original vehicle is sufficient to avoid the need to marinise if possible)
Can be used also for air prop experiments

Those are the lines that I am thinking along. The tiniest 100hp will be most attractive to a slightly bigger unit with way more hp also in the running

 

Honda L engine fits you. Cheap to buy sh from a wrecked car, easy to marinize because of cast in head watercooled manifold, can be used with a standard marine transmission, different power levels, NA or turbo.
Weight, dimensions and fuel consumption on this site: What is a Viking Engine? — Viking & Valkyrie Power https://www.vikingaircraftengines.com/engine-options check the 130 and 195 versions.

 

Not really. You can start with either one. However, since you already chose an engine, then that becomes a constraint on the boat design.

 

You are comparing building a bass, which may or not be any good; we only see photos not listen to a quality recording, to designing a complex machine. You can build something that kind of works. However, designing an efficient and safe machine takes a lot more than that. To start with, what budget do you have? Also, testing equipment is a must to compare different designs. Finally, amateurs usually believe they will build something that will work properly. Mechanical systems go through lengthy testing and iterations before they become a finished product. Prototyping requires patience and the honesty to accept that a design is poor and has to be redone.

 

Please try again, this time without distorting that to fit whatever agenda it is that is causing you to follow my ponderings and making unsubstantiated claims of dismissal. That was offered as an example of the lengths and time scale I am prepared to go to for a functional implementation to a particular problem

 

There is not distortion or agenda. There is the denial on your part of accepting the realities of physics.

 

There you go again calling questions denials, maybe try another language? That you pick on my questions that include question marks and correct punctuation and call them denials in any thread but ignore one liner claims by others in the same thread are obvious signs of an agenda which probably stems from a sad spirit. Life cannot be rewound, and you can't get any moments back. Find some joys and passions that overwhelm, makes your spirit soar. Internet stuff shouldn't get a chance to bring out such a negativities out in you. Be happy and find your joy man

 

There is a valuable advice given by sages: "Follow your own advice".