Just bought a Mac 25s and need to get a trailer. How long of a trailer do I need from winch to the end of the bunks and/or the winch to the aft axle?
Thanks
Thanks
Mac 25s Trailer
- Thread starter KC135Driver
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hello all
i was in your possition about november time when i won my '86 Mac25 in a ministry charity auction.. it was on a broken trailer.. if you are looking to save some money, and buy a very good used trailer.. i know a coupel of guys who have a boat scrapping business, and they always have good single and tandem axle trailers... i bought a tandem axle, wobble wheels trailer from them.. it is an eazy loader.. heavy duty trailer.. it is about 20 ft from winch to end of trailer.. works perfect for my Mac25.. i only had to adjust the winch and bow seat (rubber front bumpers) .. i bought it for $500 from them.... i know they have others..
sincerely
Jess
i was in your possition about november time when i won my '86 Mac25 in a ministry charity auction.. it was on a broken trailer.. if you are looking to save some money, and buy a very good used trailer.. i know a coupel of guys who have a boat scrapping business, and they always have good single and tandem axle trailers... i bought a tandem axle, wobble wheels trailer from them.. it is an eazy loader.. heavy duty trailer.. it is about 20 ft from winch to end of trailer.. works perfect for my Mac25.. i only had to adjust the winch and bow seat (rubber front bumpers) .. i bought it for $500 from them.... i know they have others..
sincerely
Jess
Altho many Macs came with a single axle I think you won't regret getting a tandem and check out purplesagetradingpostdotcom/sumner/macgregor/trailer-mods I think he posted measurements.
If you are considering a new trailer, Road King Trailers has the specs for the boat. Call Ron Frisosky at 941-914-3890 and he can help you. I do trust him. I have known him for over 30 years.
crazy dave condon
crazy dave condon
Measured a drawing
Locating a drawing of your boat and measuring everything out, it looks like you need a minimum of 18 feet, not counting tongue length.
I would place at least 12 feet of bunk centered on the retracted keel area of the hull and measuring from the rear support for this bunk to the bow eye I see 18 feet.
The axle should be located behind this center of retracted keel and even further if you tow with an outboard attached.
The longer the tongue, the easier in launching and recovery.
Locating a drawing of your boat and measuring everything out, it looks like you need a minimum of 18 feet, not counting tongue length.
I would place at least 12 feet of bunk centered on the retracted keel area of the hull and measuring from the rear support for this bunk to the bow eye I see 18 feet.
The axle should be located behind this center of retracted keel and even further if you tow with an outboard attached.
The longer the tongue, the easier in launching and recovery.
When moving an axle, the suggested weight on the tongue is 10% of the total weight of trailer and boat being towed.
Yes, 10 percent
Actual weights and measurements during a slight trailer modification I made.
Catalina 22 on a heavy C channel galvanized after market trailer.
Boat , equipment and trailer weight 3000 to 3300 lbs., tongue weight at the ball 311 lbs., towed perfectly.
Extended tongue distance 18 inches, this changed the tongue weight down to 282 lbs. Change in tongue weight did not make the trailer sway, but it did add bounce to the back of a conversion van tow vehicle weighting 6200 lbs.
Moved the trailer axle back 1 1/2 inches, this changed the extended tongue weight back up to 310 lbs., eliminated the bounce.
Actual weights and measurements during a slight trailer modification I made.
Catalina 22 on a heavy C channel galvanized after market trailer.
Boat , equipment and trailer weight 3000 to 3300 lbs., tongue weight at the ball 311 lbs., towed perfectly.
Extended tongue distance 18 inches, this changed the tongue weight down to 282 lbs. Change in tongue weight did not make the trailer sway, but it did add bounce to the back of a conversion van tow vehicle weighting 6200 lbs.
Moved the trailer axle back 1 1/2 inches, this changed the extended tongue weight back up to 310 lbs., eliminated the bounce.
OK so now I have a trailer but the bunks are too low so the boat rests on the keel and the very front of the bunks when its on the trailer. I'd like to raise the bunks but how much do I raise them? What's the height from cross member of a trailer to the top of the bunks? And how far apart are your bunks?
Let's see...
Forward bunk risers about 3 inches high,
aft risers about 10 inches high,
distance between bunks is 3 feet, center to center.
Forward bunk risers about 3 inches high,
aft risers about 10 inches high,
distance between bunks is 3 feet, center to center.
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Thanks justsomeguy. How bout the distance from the bunk to the bottom of the keel? My crossmembers don't drop down quite as much as yours.
If it were me, and not being able to see what you see, I'd put the boat on the trailer and adjust the bunks to fit. If welding is involved, I'd still tack it up with the boat on the trailer, the remove the boat (or slip the trailer out from under it), and weld it up. If the bunks are new, then do all the fitting without bunk carpet, weld it all up, then carpet and mount the bunks. If you're ambitious, build the bunk supports with some vertical adjustment. But again, I can't see what you're seeing.
Well the boat is about an hour away from home right now. Also it sits on the keel and 2 points on the very front of the bunks. That deforms the hull and looks like its putting a lot of strain on the hull so I'd like to get the trailer right.
Can you tip the boat to rest on one bunk and measure the gap along the other? When you float the boat onto the trailer to take it out the keel will be fully retracted then when ready for the road you will release the keel weight back down to be supported by the trailer during travel. The goal is keep the hull as low as reasonable and supported by the bunks and half the keel carried by the trailer(swing keel).
Measure where it now sits.
Without pictures, using your description of the hull resting on the front of the bunks, but the back end of the keel sitting on a cross member is lifting the aft end of the hull above the bunks will give you the measurements needed.
The ideal setup is that when the hull is resting on the bunks thus carrying the weight of the hull, the keel cranked up to it’s highest position would be above this trailer crossmember. The keel is then lowered down onto this crossmember to carry some of the weight of the keel, the hull weight must not sit on a swing keel! Again, ideally this clearance between the keel and the crossmember should not be very much, an inch or two, so that the boat is sitting on the trailer as low as possible to make for easier launching and retrieval.
The boat should ride on the trailer as low as possible, the keel should clear the trailer and bunks by a couple inches and then lower down for keel support after recovery.
From what you have described, I would measure to find the largest difference between the hull and the bunk. Add 1 to 2 inches for the clearance of the keel and then raise the back end of the bunks that much. If the hull is already touching the front of the bunks I would not change that measurement.
If after only raising the back end of the bunks, the boat looks like it is resting with the bow downhill, that would be perfect. Because of the angle of the launch ramp the stern always floats free first, the bow is where you have to back further into the water for it to float, so keeping the bow as low as possible is more advantagest. When the boat is parked on the trailer raise the trailer jack so the stern is level or lower to allow the rainwater to drain properly.
The distance between the bunks should be between 3 and 4 feet. The boweye attached to the front of the trailer will keep the forward part of the hull from moving from side to side and sliding to the rear. A strap over the stern attached to the trailer, near the area of the back end of the bunks will keep the stern from walking from side to side as the trailer bounces down the highway. I make this strap very tight and when I park the rigging I release some of this pressure until I tow again.
Without pictures, using your description of the hull resting on the front of the bunks, but the back end of the keel sitting on a cross member is lifting the aft end of the hull above the bunks will give you the measurements needed.
The ideal setup is that when the hull is resting on the bunks thus carrying the weight of the hull, the keel cranked up to it’s highest position would be above this trailer crossmember. The keel is then lowered down onto this crossmember to carry some of the weight of the keel, the hull weight must not sit on a swing keel! Again, ideally this clearance between the keel and the crossmember should not be very much, an inch or two, so that the boat is sitting on the trailer as low as possible to make for easier launching and retrieval.
The boat should ride on the trailer as low as possible, the keel should clear the trailer and bunks by a couple inches and then lower down for keel support after recovery.
From what you have described, I would measure to find the largest difference between the hull and the bunk. Add 1 to 2 inches for the clearance of the keel and then raise the back end of the bunks that much. If the hull is already touching the front of the bunks I would not change that measurement.
If after only raising the back end of the bunks, the boat looks like it is resting with the bow downhill, that would be perfect. Because of the angle of the launch ramp the stern always floats free first, the bow is where you have to back further into the water for it to float, so keeping the bow as low as possible is more advantagest. When the boat is parked on the trailer raise the trailer jack so the stern is level or lower to allow the rainwater to drain properly.
The distance between the bunks should be between 3 and 4 feet. The boweye attached to the front of the trailer will keep the forward part of the hull from moving from side to side and sliding to the rear. A strap over the stern attached to the trailer, near the area of the back end of the bunks will keep the stern from walking from side to side as the trailer bounces down the highway. I make this strap very tight and when I park the rigging I release some of this pressure until I tow again.
Sorry, got a little busy today.
Kind of hard to accurately measure with the boat on the trailer, but it looks to be about 18-20 inches from the top of the 2x6 bunk down to the bottom of the V.
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No, with the boat on the trailer is what you want!
Measure from the bottom of the HULL down to the top of the BUNK at a point where the hull sits on the bunk, not the trailer, not the keel.
Find the largest distance between the hull and the bunk at any point of contact!
Add the 1 to 2 inches to this measurement.
Remove boat.
Raise the back end of the bunks by the amount of this new measurement. Loosen the center supports of the bunks.
Place boat back on trailer with the keel all the way up. The keel should be 1 to two inches above the trailer cross member with the back end of the bunks raised this new amount.
Raise the center of the bunks up to meet the hull at that location.
Lower keel.
Tow.
Measure from the bottom of the HULL down to the top of the BUNK at a point where the hull sits on the bunk, not the trailer, not the keel.
Find the largest distance between the hull and the bunk at any point of contact!
Add the 1 to 2 inches to this measurement.
Remove boat.
Raise the back end of the bunks by the amount of this new measurement. Loosen the center supports of the bunks.
Place boat back on trailer with the keel all the way up. The keel should be 1 to two inches above the trailer cross member with the back end of the bunks raised this new amount.
Raise the center of the bunks up to meet the hull at that location.
Lower keel.
Tow.
Thanks justsomeguy. I appreciate the measurements. The trailer is currently at the fab shop to get the bunks raised by about 12" all around.
Watercolors-If I did that the boat would be at a significant angle down. Also, as previously mentioned the boat is not easily accessed as it is about an hour away.
Watercolors-If I did that the boat would be at a significant angle down. Also, as previously mentioned the boat is not easily accessed as it is about an hour away.
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