Added second axle what do you think?

[OverEasy]

Hi Ris!

Just wondering what was included in the 4175 lb weight you referred to.
Is that just your Mac or did that include the trailer?

30 gal of water in a plastimo water tank x 8 lb/gal = 240 lbs
4 Trojan 105 batteries x 62 lbs each = 248 lbs

What size and make is your engine?
Does your 4175 lb weight include fuel load?

Best Regards,
Over Easy

[ris]

We were fully loaded for a 2 week trip. Water, food, clothing, fridge, fenders, dodger, cockpit enclosure 30 gal fuel and 60 hp Honda everything EXCEPT the mast, rudders and other sailing stuff. (we use the Mac as a trawler, not a sailboat). Pulled the boat on trailer onto scales, unhooked truck and drove truck off scales. Loaded boat and trailer weighed 4,175 lbs. Hopefully this answers your question OverEasy. Our blog which is "thejillkristy.wordpress.com" documents our boat rebuild in 2015 and 2016. You have to go down the blog page to get to year section and pick 2015 or 2016 to see all the mods. Most of the mods were copied from those who were on this site before 2016. We also added two 3500 lb axels to our trailer. We are headed to Lake Champlain in 2022 so hopefully we will see you. I have been reading your trip report for the last two days. Have fun.
Richard

[OverEasy]

Hi Ris!

Thanks for the info!
We will look up your blog!
Thank you for the kind words
Yes, it would be great to meet you on Lake Champlain in 2022!!!

Best Regards,
Over Easy

[Sheppie62]

Well I ran out of time and didn’t make it to the scales. I test drove it a bit and it felt ok loaded with 20 Gallons and fully loaded with supplies for week at Harbor (left boat there in slip). I’m guessing my loaded weight must be similar to Ris’s . It felt a bit light towing 60+, but no wobbles. So I’m thinking I’m going to move axles back another 3-6”. I wish I had weighted it , cause I’m just guessing now. Anyways if I put larger gas tanks I will need more tongue weight for sure. I thinking about moving axles back 3-6” more, again my center axle balancer is 9” back from original single axle center point. So if I move the axles back 3-6” that would be 12” or 15” back total. I also increased rear trailer weight by extending the trailer to back of boat for motor support while trailering

[OverEasy]

Hi Sheppie62!

Lookin’ Good !

Given that you were just on the estimated percentage of tongue to loaded trailer weight moving aft an additional 6” wouldn’t hurt. (Better than too light,)

Hope you can get a weigh when you reload at haul out whenever that might be.

Congratulations on the trailer AND gettin it wet!

Best Regards,
Over Easy

[Sheppie62]

I also extended the trailer to the back of boat to support motor while trailering,

[OverEasy]

Hi Sheppie62!

The extension looks great
and the multicolor I process paint job is interesting
but what are the three trailer hitch tubes for? (There must bu a story there….)




Are you having your motor support tube run all the way through the three cross members?

Best Regards,
Over Easy

[Sheppie62]

Overeasy, the motor support tube goes thru the back cross member and then slides into a short trailer tube on backside of the next crossmember, but doesn’t go thru it. It does not go to the 3rd from back crossmember. The 3rd from back crossmember is an original, and very rusty needing to be replaced before hauling boat again. I will replace tongue and it’s short crossmember as well. Then only part that will be original will be the main frame rails. The frame extension was too flexible to hold up motor, so I built the side posts and rails and made a truss to strengthen it. The back cross member does not give any support to boat (that wasn’t the original intention). I was quite surprised by the flexibility of the 4” C channel frame rails. The back strap going over boat to trailer is actually helping stop some of the flexing. Motor support is very sturdy now with additional straps from motor support to the back of the boat. I was thinking about just doing the typical angled support from rear of trailer to the lower unit, but decided not to as I always have to do the “Mac bump” to get boat completely on the trailer. The thought of doing the “Mac Bump” with the heavy motor and setback makes be cringe! Hence the new support that would allow the lower unit to slide forward at same angle, plus gives the lower unit/ prop some impact protection. I may replace the truss metal straps with one long cable to provide tension adjustability. I didn’t plan all this out, I just did one thing and then did next thing and it led to this. I plan on many long road trips, and protecting the transom from road bumps was my main concern. I extended the setback plate to the bottom of the boat also for better support and to protect the ballast tank inside.

[OverEasy]

Thanks for the clarification!
Makes sense.

Truss structure can make things a lot stronger per unit weight.
There are several options that could work.

Old iron replacement… been there… as you well know it’s always better to replace earlier rather than…oopsie …too late

Be aware if you do a cable truss that it only works in tension and can flex considerably when the load reverses ( like in a bumpy road ).
I’ve seen a couple cases where that relaxation led to cyclic fatigue of weld joints.

Yes, things evolve and sort of take on a life of their own with some projects.
Still very impressed with your motor mount system.
That is very cool!

Best Regards,
Over Easy

[Sheppie62]

Very good point about the cable and flexing! I can see now it would be very bad when trailer is being towed empty. I prestressed the current tension rods by lifting the rear of trailer 1 1/2” before installing for tension, but even those flat bars can flex if trailer is empty which could lead to the square tubing welds cracking. The square tubing insides rusting concerns me. I drilled a 1/4” hole for drainage top and bottom after it’s been submerged in salt water (1 week later) and flushed them out when I got home with hose water. I was thinking I was going to fill tubes with rustolem paint let it drip out lower hole. What would you recommend I do to prevent corrosion now before painting. I used the square tubing because that’s what I had.

[OverEasy]

Hi Sheppie62!

For what it’s worth….
When I’ve had to weld square tubes to flat surfaces that have any chance of getting wet I drill a drain hole in the flat surfaces top and bottom. The two holes allows the cavity to “air out” after draining.

(Seldom can one have an airtight weld the actually holds up over time.... it’s generally just not worth it anyway…)

What I’ve found works best over time isn’t trying to apply paint to the interior unless I can flood fill it with an oil enamel paint (after throughly degreasing) but to apply a “residual surface oil” like is used for motorcycle chains (something like PJ1 or something similar). A couple shots generally is sufficient. I generally do that after painting the exterior surfaces.

I’ve found that that it’s hard to get a good well bonded painted surface inside tubing that holds up over time …. Generally I’ve found the penetrating residual oil surface does better at preventing rust, especially if it is part of the structure’s periodic maintenance.

Looking at your photos it looks like you can get to the bottom surfaces of where square tubes are welded so you might be able to drill upwards to penetrate into the void space if desired.

I like the motor support. It’s better than just relying upon the flip down (or up) that the motor comes with. It relieves the hydraulic tilt pistons from the road transit compression loads.

Unfortunately our trailer doesn’t allow us to make a functional support like you have made.
We use the flip support but I’m in the process of figuring out how to add a secondary support (wedges?) to backstop the flipper
though still not as nice as your support!

Best Regards
Over Easy

[adventuren1]

I think what you've done is a good idea, and allows for tuning for tongue weight. Just be advised that the OEM pole tongue, which is 3x3x3/16" HSS (structural tube) of unknown but probably low grade steel, has a nasty habit of rusting right at the most highly stressed location - where the two channels meet it. If you're increasing the tongue weight, which is a good thing if the tow vehicle can handle it, do watch for that pole tongue bending. There's not a large design factor on that member with the 350 lb or so tongue weight the 3500 lb trailer would have been designed for.

And while you're at it, tap around the bottom of that pole tongue with a ball peen hammer, listening for a nice ring. If it's rusting, it'll sound dull, or duller than the top or further toward the coupler. More than one member here has had that pole tongue fail, including at least one on the road. Not something you want if you can take steps to avoid it.

I sure wish I had read this post before I bought my boat! Mine had been converted to a tandem axle also. I just put all new brakes and tires on it a month before it became scrap metal.

[OverEasy]

Ouch!!!
That hurts!

Glad you had it happen in what appears to be a “controlled” situation, as opposed to booking down the highway and becoming part of the evening news broadcast…..

Several decades ago I had an axle attachment fail on a trailer such that the trailer swung 90 degrees into the next lane.
Fortunately it was an empty lane any no one else was involved.
Scared the bejebers out of me!!@#&$%….

Glad you were able to deal with your SNAFU before it became a FUBAR.

Best Regards,
Over Easy

[Tomfoolery]

I think what you've done is a good idea, and allows for tuning for tongue weight. Just be advised that the OEM pole tongue, which is 3x3x3/16" HSS (structural tube) of unknown but probably low grade steel, has a nasty habit of rusting right at the most highly stressed location - where the two channels meet it. If you're increasing the tongue weight, which is a good thing if the tow vehicle can handle it, do watch for that pole tongue bending. There's not a large design factor on that member with the 350 lb or so tongue weight the 3500 lb trailer would have been designed for.

And while you're at it, tap around the bottom of that pole tongue with a ball peen hammer, listening for a nice ring. If it's rusting, it'll sound dull, or duller than the top or further toward the coupler. More than one member here has had that pole tongue fail, including at least one on the road. Not something you want if you can take steps to avoid it.

I sure wish I had read this post before I bought my boat! Mine had been converted to a tandem axle also. I just put all new brakes and tires on it a month before it became scrap metal.

It's actually not very hard to replace that pole tongue with new. Use 3x3x1/4" HSS (hollow structural section, aka 'tube steel') and have a welder cut and grind out the welds and weld in a new piece. Reweld the existing coupler, or replace it. Good for another 30 years.

[adventuren1]

I think what you've done is a good idea, and allows for tuning for tongue weight. Just be advised that the OEM pole tongue, which is 3x3x3/16" HSS (structural tube) of unknown but probably low grade steel, has a nasty habit of rusting right at the most highly stressed location - where the two channels meet it. If you're increasing the tongue weight, which is a good thing if the tow vehicle can handle it, do watch for that pole tongue bending. There's not a large design factor on that member with the 350 lb or so tongue weight the 3500 lb trailer would have been designed for.

And while you're at it, tap around the bottom of that pole tongue with a ball peen hammer, listening for a nice ring. If it's rusting, it'll sound dull, or duller than the top or further toward the coupler. More than one member here has had that pole tongue fail, including at least one on the road. Not something you want if you can take steps to avoid it.

I sure wish I had read this post before I bought my boat! Mine had been converted to a tandem axle also. I just put all new brakes and tires on it a month before it became scrap metal.

It's actually not very hard to replace that pole tongue with new. Use 3x3x1/4" HSS (hollow structural section, aka 'tube steel') and have a welder cut and grind out the welds and weld in a new piece. Reweld the existing coupler, or replace it. Good for another 30 years.

The rest of the trailer was in no better shape. Sometimes they just need to die