OB up or down?

A forum for discussing issues relating to trailers and towing MacGregor sailboats.
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Tomfoolery
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Re: OB up or down?

Post by Tomfoolery »

OverEasy wrote: Wed Oct 28, 2020 9:58 pmWe just got a 400 lb rated bath scale to check the tongue weight of the boat and trailer. I'm aiming to get a tongue weight of above 300# but below 325# to hopefully avoid any tail wagging. We will get this verified before going back up on the highway to see how it handles at higher speeds.
300-325 lb sounds light to me. Normally you want at least 10% of trailer gross on the ball, and more is better. As long as you're not overloading the tow vehicle, which is certainly possible with a minivan.

My boat's PO towed it with a Caravan, all over the place, so I'm sure it's quite doable. But do be careful about too little (or too much) tongue weight.
Tom
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Re: OB up or down?

Post by Inquisitor »

Tomfoolery wrote: Thu Oct 29, 2020 5:29 am 300-325 lb sounds light to me. Normally you want at least 10% of trailer gross on the ball, and more is better. As long as you're not overloading the tow vehicle, which is certainly possible with a minivan.

My boat's PO towed it with a Caravan, all over the place, so I'm sure it's quite doable. But do be careful about too little (or too much) tongue weight.
Brings to mind...

Considering all the variability of...
  • Monday vs Wednesday build quality
  • Steel vs Aluminum trailers
  • Mods that someone might incorporate 8)
  • Provisioned for the road... fuel, water, food, toys...
Is there any good ideas (or products) how to go about weighing the boat/trailer so that we can the do that 10% tongue weight?
Odysseus, expert on the Siren's call
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Tomfoolery
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Re: OB up or down?

Post by Tomfoolery »

Inquisitor wrote: Thu Oct 29, 2020 5:47 am
Tomfoolery wrote: Thu Oct 29, 2020 5:29 am 300-325 lb sounds light to me. Normally you want at least 10% of trailer gross on the ball, and more is better. As long as you're not overloading the tow vehicle, which is certainly possible with a minivan.

My boat's PO towed it with a Caravan, all over the place, so I'm sure it's quite doable. But do be careful about too little (or too much) tongue weight.
Brings to mind...

Considering all the variability of...
  • Monday vs Wednesday build quality
  • Steel vs Aluminum trailers
  • Mods that someone might incorporate 8)
  • Provisioned for the road... fuel, water, food, toys...
Is there any good ideas (or products) how to go about weighing the boat/trailer so that we can the do that 10% tongue weight?
CAT scales. Three-section scale platforms, though you only need two of them. BUT, you can put the front axle on the forward platform, the rear axle on the middle one, and the trailer on the last if you want axle weights for all three (or four, if the trailer has two).

$12 initial weigh, and $2.50 for a reweigh within 24 hours, though you're supposed to have the same tractor/trailer combo. Might have to pay another $12 to weigh just the tow vehicle again.

Or use a bathroom scale. Make sure the trailer frame is level, as it should be on the ball too, and put a 2x4 on end under the coupler straight down to the scale. Works best with mechanical scales, but if you're quick on the crank, it can work with a digital scale.

If the scale isn't heavy enough, you can use a 2:1 force beam (2x4 on the flat), with one end on the scale, the other on blocking to bring it up to the same elevation as the scale, and a 2x4 on end to the mid-point of the beam. Scale will read half the coupler (tongue) load.


Image
Tom
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Re: OB up or down?

Post by Inquisitor »

Tomfoolery wrote: Thu Oct 29, 2020 6:25 am CAT scales.

If the scale isn't heavy enough, you can use a 2:1 force beam (2x4 on the flat), with one end on the scale, the other on blocking to bring it up to the same elevation as the scale, and a 2x4 on end to the mid-point of the beam. Scale will read half the coupler (tongue) load.
Wouldn't have guessed (before your suggestion) that those truck scales had enough resolution for our little boats... but looking it up... they say 20 lb resolution. 8)

Looking at the Mac website archive, I see it says with Boat, Motor and Trailer, its 3440 lbs.
  • Anyone confirmed the specs with a real world weighing? Meaning with fuel, water and provisioned.
  • It would be interesting to know the variability of member's boats. Would love to know what Highlanders displaces.
  • I would assume the stripes were placed consistently in the mold before gelcoating. Anyone know if they are indicative of some gross displacement and what that might be? I've never come close to touching the bottom of the stripe.
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Tomfoolery
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Re: OB up or down?

Post by Tomfoolery »

Recent CAT scale printout of my van, sans trailer. FYI.

Image

I weighed it because the ride seemed excessively harsh, and sure enough, it was about a ton under the GVWR of 11,030 lb, a ton under rear axle GAWR of 7720 lb, and half a ton under front axle GAWR of 4410 lb. So I adjusted tire pressures down to manufacturer's recommended pressure for 110% of actual tire loads, which is a lot lower than door post pressure, especially for the rear duals. Rides way mo' betta' now. But I digress.

I haven't weighed my boat and trailer, but there's no way it's less than 4000 lb. I don't know anyone who has actually weighed theirs and had it come in under 4000 lb in fact. The trailer is only 3500 lb GVWR. But at least mine has a second axle, so tires and bearings are way underloaded. I even modified the leaf springs so they're softer. 8)
Tom
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OverEasy
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Re: OB up or down?

Post by OverEasy »

We were really fortunate that the prior owners of Over Easy had done a great job of keeping the original boat papers and manuals!

For reference only:
* The original empty weight for a 26X was listed as 2350 lbs (Note1 & 2)
* The original Macgregor trailer weight was listed as 710 lbs
** The original combined 26X & trailer weight combined 3060 lbs

Note 1: This does not appear to account for any engine, fuel or accessories.
Note 2: We assume though that the empty weight listed would have included the weight of the baseline original mast, boom, rigging, and sails.

As was mentioned things change over time and there are always other variability aspects to account for.
As such we are going to be offloading what we can from the boat and also minimizing what we carry in the van.
The towing specialists agree that a tongue weight of between 7% to 10% of the trailered load is the target but to avoid going too much. If the trailered load isn't stable within that range there is something amiss that needs to be addressed. (Too light will definitely lead to fishtail oscillations and too heavy can unnecessarily/excessively load the tow vehicle's rear suspension as was mentioned. Sort of a Goldilocks aspect to get the tongue loaded enough but not too much. 😏.)
So far all our numbers are adding up within the various capacity 🚐⛵ recommendations.😏
So far so good!😎

I appreciate the suggestion of the "load divider" board. Especially the photo with the bevel edge vertical transfer board to make it easier to locate it accurately. My Dad had done a similar set-up when I was a growing up to measure the tongue weight for our travel trailer. (He liked wood working and had a hardwood set with a double bevel for the vertical and a pair of double bevel lower transfer fixed and scale pivot blocks. He used to check everything before just about every trip we went on which was a great way to learn the functional math as a kid. It was actually a fun routine.)

If we can get to some weigh scales we will also get that done as well. Unfortunately there do not appear to be any locally that we have found but it is something we would like to get accomplished before our trip.
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Tomfoolery
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Re: OB up or down?

Post by Tomfoolery »

OverEasy wrote: Thu Oct 29, 2020 10:23 pmIf we can get to some weigh scales we will also get that done as well. Unfortunately there do not appear to be any locally that we have found but it is something we would like to get accomplished before our trip.
Weighing just the tongue should be fine if that's your main concern, but you can always stop at a scale once on the road for the whole shebang. Assuming you take road trips with it, of course.

https://catscale.com/cat-scale-locator/
Tom
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OverEasy
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Re: OB up or down?

Post by OverEasy »

Wow!
THANK YOU FOR THE SCALES LOCATOR MAP!!!! 8)
That will come in really handy as we travel, modify and "age" with Over Easy (it will also allow us to keep the inevitable weight creep monitored and in check 🙄).
K9Kampers
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Re: OB up or down?

Post by K9Kampers »

OverEasy wrote: Thu Oct 29, 2020 10:23 pm If we can get to some weigh scales we will also get that done as well. Unfortunately there do not appear to be any locally that we have found but it is something we would like to get accomplished before our trip.
Give a call to BCEP on Rt. 107 in Pittsfield. We used their scale our first year when we were towing the original Mac trailer behind the Explorer. The challenge is to pick a day / time to make all the weighs without tying up the scale for usual business. Should take less than 10 minutes if it takes more than 5. I dont recall our numbers from 14 years ago.
OverEasy
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Re: OB up or down?

Post by OverEasy »

Thank you!
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