Finding level

Ask a question...get an answer (or two).
Post Reply
David VanDenburgh
Skilled Systems Installer
Posts: 244
Joined: Sun Oct 16, 2005 8:33 pm
Boat Name: Ariel
Boat Type: Cape Dory 36
Location: St. Joseph, Michigan
Contact:

Finding level

Post by David VanDenburgh »

Would it be a mistake to use the floors that support the mast step as a reference for level fore and aft? Here's a photo:

Image

This is on the Pearson Ensign that my class is restoring. We're ready to start glassing in the cockpit grate supports, but I need to establish level fore and aft first. If the mast step floors aren't a reliable reference, any suggestions about what is?

Thanks!

David
User avatar
Tim
Shipwright Extraordinaire
Posts: 5708
Joined: Tue Apr 01, 2003 6:39 pm
Boat Name: Glissando
Boat Type: Pearson Triton
Location: Whitefield, ME
Contact:

Re: Finding level

Post by Tim »

Your best bet as "level" reference points will be the waterline mark (probably a factory scribe) at the stem and centerline of the aft waterplane. If you level the boat based on these two points, you can then determine what, if anything, in the inside of the boat can serve as your level basis, or else create your own as needed.

I also think that the bottom of the keel on an Ensign happens to be parallel to the waterline--i.e. level--but I am not sure offhand about this.
---------------------------------------------------
Forum Founder--No Longer Participating
David VanDenburgh
Skilled Systems Installer
Posts: 244
Joined: Sun Oct 16, 2005 8:33 pm
Boat Name: Ariel
Boat Type: Cape Dory 36
Location: St. Joseph, Michigan
Contact:

Re: Finding level

Post by David VanDenburgh »

Thanks! I'll have to take a close look for those scribed lines.

A great resource as always.

David
Skipper599
Candidate for Boat-Obsession Medal
Posts: 302
Joined: Mon Mar 16, 2009 1:48 am
Boat Name: "MACUSHLA"
Boat Type: Passage 24-30 Cutter
Location: Cloverdale in Beautiful BC Canada.

Re: Finding level

Post by Skipper599 »

Tim, when you make a comment such as: "level the boat", I'm thinking you probably assume everyone will know exactly how to do that. ... NOT ... I myself have played around for numerous hours, not really knowing if what I was doing would end up ... LEVEL.

Your comment about scribed lines at the waterline are certainly valid ... my hull happens to be fibreglass and so, I put my faith in the moulded gelcoat W/L ... but this still required I find a way to actually level the hull, not only fore and aft, but also athwartships ... I eventually used a garden hose, to which I attached a 12" length of clear plastic hose to each end, taping them to straddle the waterline. First, fore and aft, and then athwart. ... I mixed up a gallon of colored water using food coloring, filling the hose from one end with the aid of a jug and funnel.

Initially, I found the liquid too 'mobile' so made a plug out of a piece of old poly towel rail with a small vent hole to dampen the air flow. This worked very well for me. In addition and for reference only, I hung a plumb-bob from a central point in the cabin ceiling, about 6" aft of the main bulkhead, measuring to find it actually hung parallel to the bulkhead and also centered on the cabin sole. Of course, that could have been pure luck.

Not completely satisfied, I set a Laser level over the mast step mounted on the cabin top, and then took measurements down to the W/L, all of which came within acceptable figures (eg:within a 1/16" ) to assure me the boat was as level as was humanly possible.

Oh, yes, I also set a carpenters level across the main hatch rails and found it was level also ... again, possibly pure luck? ... and, for the record, I have checked the level twice each year ever since.

My question to all you mastercraftsmen out there: Is there a better or easier way to do this job to assure complete accuracy?
I am: Bob of Wight.

s/v 'Ros Na Cosquin'
a 'Passage - 24'

There are good ships, there are wood ships, and these ships sail the sea

But the best ship, is friendship and may this always be! ... ... ... A prayer from Ireland.
Hirilondë
Master of the Arcane
Posts: 1317
Joined: Thu Dec 28, 2006 8:50 am
Boat Name: Hirilondë
Boat Type: 1967 Pearson Renegade
Location: Charlestown, RI

Re: Finding level

Post by Hirilondë »

Skipper599 wrote: Your comment about scribed lines at the waterline are certainly valid ... my hull happens to be fibreglass and so, I put my faith in the moulded gelcoat W/L ... but this still required I find a way to actually level the hull, not only fore and aft, but also athwartships ... I eventually used a garden hose, to which I attached a 12" length of clear plastic hose to each end, taping them to straddle the waterline. First, fore and aft, and then athwart. ... I mixed up a gallon of colored water using food coloring, filling the hose from one end with the aid of a jug and funnel.
The use of a water level when done carefully as it certainly seems you have is extremely accurate. I would feel quite confident in what you have done.
Skipper599 wrote:In addition and for reference only, I hung a plumb-bob from a central point in the cabin ceiling, about 6" aft of the main bulkhead, measuring to find it actually hung parallel to the bulkhead and also centered on the cabin sole. Of course, that could have been pure luck.
It was probably skill on the part of the builder, but I would never use this to establish level until I had proven by another means that the boat was level and then did this test. And even so, it isn't as accurate as using the original water line and your water level.
Skipper599 wrote:Not completely satisfied, I set a Laser level over the mast step mounted on the cabin top, and then took measurements down to the W/L, all of which came within acceptable figures (eg:within a 1/16" ) to assure me the boat was as level as was humanly possible.
Hmm, I'm not sure that this information tells you anything except that the top of your mast step is parallel to your water line. If this is so, then in the future you can use your mast step to level the boat, but again, I don't think this is as accurate as you water level/waterline method. But to say this assures you of anything else would be a mistake.
Skipper599 wrote:Oh, yes, I also set a carpenters level across the main hatch rails and found it was level also ... again, possibly pure luck?
Maybe luck, maybe skill, but either way it doesn't verify anything. You don't even know if it was meant to be level.

All of your secondary measurements may offer you some peace of mind, but your first method was the best. And it seems that your boat was layed out and built to a much higher standard than most.
Dave Finnegan
builder of Spindrift 9N #521 'Wingë'
--------------------------------------------------------------------------------------------------------------------------------------------------------------------
Gresham’s Law of information: Bad information drives out good. No matter how long ago a correction for a particular error may have appeared in print or online, it never seems to catch up with the ever-widening distribution of the error.
Abier
Bottom Sanding Grunt
Posts: 6
Joined: Fri Jan 15, 2010 2:21 pm

Re: Finding level

Post by Abier »

I also have a question about "level". I'm sure since you're restoring an Ensign, it will be to class rules and therefore "balanced" as it was from the builder, so the scribed lines should be an accurate reference. My question is this: If I significantly alter my boats' interior and cabintop, and eliminate a large amount of weight, won't I change the way the boat sits in the water? I seem to remember Tim's Daysailor being test floated, was that to find a new waterline?
User avatar
Ceasar Choppy
Boat Obsession Medal Finalist
Posts: 622
Joined: Thu Mar 09, 2006 11:05 am
Location: Port Starboard, MD

Re: Finding level

Post by Ceasar Choppy »

If you have scuppers in the cockpit, hopefully you'll "level" the cockpit in their direction so that water drains quickly. Level is always relative to something else on a boat!
Skipper599
Candidate for Boat-Obsession Medal
Posts: 302
Joined: Mon Mar 16, 2009 1:48 am
Boat Name: "MACUSHLA"
Boat Type: Passage 24-30 Cutter
Location: Cloverdale in Beautiful BC Canada.

Re: Finding level

Post by Skipper599 »

... Ah yes. I did give that consideration, having boarded another identical boat a few years ago to find lots of water in the forward end of the cockpit. The reason for this was, the owner/builder installed a huge water tank under the v-berth, putting her 'head-down' at the dock. Apparently it levelled off when the crew was aboard ... or so he claimed. Strangely, it did not when he and I were aboard.

... Anyway, I kept that in mind for a very long time and, when the time finally came, I installed scuppers in all four corners of the cockpit in my boat. I will definitely not be suffering the same problem ... also, my water tanks are located under the cabin sole, and on top of the encapsulated lead ballast.
I am: Bob of Wight.

s/v 'Ros Na Cosquin'
a 'Passage - 24'

There are good ships, there are wood ships, and these ships sail the sea

But the best ship, is friendship and may this always be! ... ... ... A prayer from Ireland.
Post Reply