Custom Sevylor Fish Hunter Transom

[dopherman]

Hello Friends,

First post here, thought I'd share a project I've been working on for my Sevylor HF 280 Fish hunter. Bought a small outboard, and needed a transom!



This was definitely the hardest part to design, I used it to connect the main frame arms to the fittings built into the boat (similar to the manufacturers transom) as seen at the top of this picture:



The frame arms were 3/4 inch electrical conduit, which I bent with a pipe bender. I thought it might be a little stronger and more durable than copper. For the transom itself, I found a solid piece of hardwood at my job left over from renovations that I thought would do nicely.



I wanted to use the manufacturers fittings as much as possible, so I used some short pieces of 1/2 inch conduit pipe which I bent and cut to fit naturally



to be continued...

 

[dopherman]

Re: Custom Sevylor Fish Hunter Transom

...continued

Heres what it looks like installed:



and here it is after the pipe insulation (it gets hot during the summer in Texas)



Hope you like it, looking forward to more mods in the future!

Ask away if you have any questions about anything I've done here

-Doph

 

[Sea Rider]

Re: Custom Sevylor Fish Hunter Transom

Which electric or gasoline engine HP will you be mounting to power that sib ? Really doesn't matter much, all those entry inflatables only accepts very small portable OB's. Although your set up looks real nice will have several unwanted down issues that boaters encounters after launching boat/engine combo at day one due to :

1-Boat is made from real thin pvc gauge fabric.
2-Tubes are exterior pleated welded, doesn't have inside/outside reinforced seams.
3-Has a exterior non rigid transom board mounted on rear tube.
4-Has a inflatable deck.
5-Doesn't have an inflatable keel.

Bottomline : You can olny inflate that sib to a much less pressure due to having welded outside seams, or risk bursting tube's side seams. When giving engine juice, the prop pushes forward along rear tube flexing it, the more you throttle, the more it will flex. To avoid this, must throtttle enough as to have just flat displacement speed. Being a flat infltable with too much hull drag, with too much rear tube flexing along a small engine will doubt it will plane. Anyway is a excellent boat/engine starter.

Used to have many moons back a French Sevlor Caravelle K-86 around 3 meters in lenght, made some real state of the art reinforcing mods at back transom board along topping more air psi than max allowed. On it's maiden voyage was tested with a 2 strokes 3.5 HP, at 3/4 throttle the rear tube flexed so much that gave an awkward displacement along too much hull drag. The only way to achieve a nice flat displacement was to juice the engine at max 1/2 throttle.

Months latter was caught by a wave that burst one laterall seam, had it's Waterloo there, RIP K-86. That total loss moved me faster than wanted to the next boating level, a OMC 305 with built in transom and an Evi 9.9 HP.

Happy Boating

 

[dopherman]

Re: Custom Sevylor Fish Hunter Transom

The motor I have is a 3.0hp sears gamefisher model made by tanaka.

Unfortunately towing isn't at option for me at this point, so this set up has the added advantage of being able to fold up in the back of my little suv as opposed to many rigid inflatables.

I was actually able to get my hands on one of the discontinued "boat boots" made for this model. It's a fabric sleeve that I've found really helps with the rigidity when the boat is fully inflated inside. I'm hoping that the fabric cover along with the solid floor will fight some of the flexing caused by the motor, but that is a test for next weekend!

-Doph

 

[mrdrh99]

Re: Custom Sevylor Fish Hunter Transom

Try asking copper fox....he is on the boards frequently, mainly now in the mariner 4 thread. He has had a couple different sevylor fh boats. More expierence with them than anyone on here that I'm aware of

 

[CopperFox]

Re: Custom Sevylor Fish Hunter Transom

Hi there Dopherman! Welcome to the inflatable modders addiction support group! Like MrDrH, I've now put a hard floor and raised swivel seats in 2 boats, one of mine being the HF-360. I can't say that either of mine included transom modification though. Given what Sevylor charges for those things and the poor quality of them, your time was well spent. That's some quality work you're showing and a very nice set-up. I expect with the improved arm design, you should be able to transfer a little more of that thrust to the whole boat and not just the back.

I see you've already gotten the standard 'doom and gloom' report. All that it is missing, are the actual words 'pool toy', but now that's out of the way you can start to enjoy your boat.

Do you plan to fish with it? Are any more mods in the future? Maybe, improved seating? Keep us in the loop. I know discussion and photos here were very helpful to everything I did and I'm sure others to follow will be very appreciative of any pix or tips you'll provide. I've pretty well documented my work on the HF-360 and Intex Mariner 4 here over the last 2-3 years if you're interested. Don't hesitate to ask if you have any questions, or offer suggestions of your own. This really is a very helpful community.

 

[dopherman]

Re: Custom Sevylor Fish Hunter Transom

Thanks for the words of encouragement! I do have other modifications in mind, like seating decks, lights, etc., but I haven't been great at focusing on one at a time, so it's been taking awhile. you can kinda see in my last picture the flooring in progress. I used a plywood cutout like everyone else, and pipe insulation around the edges. before I'm finished with it I plan on sealing it up and doing carpeting.

I've seen some youtube videos and other forums of people doing sub flooring slats, or using pvc pipe long ways underneath for some reason. is there any reason this would be necessary? the single plywood sheet seemed very stable to me, and anything extra kinda seemed like over engineering...

thanks for your time!