Hi All,
The stems on our Prospector are sitting almost 1/4" above the top of station six, and we're about to continue shaving down the stem, and we believe we need to have the stem flush with the top of the station before doing so. It looks like most other folks have it flush, and we don't know why ours isn't from the get go. Has anyone run into this problem? And should we flush it down before we continue? Advice is greatly appreciated!
Thanks,
WIl, Kelly and Nick
Flush stems?
Prospector stem
Wil et al:
Station 6 profile will be at 23 + 1/16" if lofted from CanoeCraft manual. The forces the stem mold height, at the juncture of station 6, to be 22 + 5/16". This will vary about 1/32" depending which side of station 6 is your reference edge.
You didn't say whether or not your stem is exactly 3/4" high.
I would suggest you find out why the 1/4" difference before you start shaving on the stem. If the other stations are also off, you will have problems later when you start stripping the bilge.
Also, I hate to even suggest this, but if you're using tape measure, is it accurate?
And, if you added material to the bottom of the molds, to clear the strongback, did you cut accuractly?
Ed..
Station 6 profile will be at 23 + 1/16" if lofted from CanoeCraft manual. The forces the stem mold height, at the juncture of station 6, to be 22 + 5/16". This will vary about 1/32" depending which side of station 6 is your reference edge.
You didn't say whether or not your stem is exactly 3/4" high.
I would suggest you find out why the 1/4" difference before you start shaving on the stem. If the other stations are also off, you will have problems later when you start stripping the bilge.
Also, I hate to even suggest this, but if you're using tape measure, is it accurate?
And, if you added material to the bottom of the molds, to clear the strongback, did you cut accuractly?
Ed..
Ed Alger
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David James
- Posts: 223
- Joined: Tue May 11, 2004 9:04 pm
- Location: Glenview, Illinois
Hey Wil,
I had the same problem with my F17. To make the stem flush with the station I simply (properly?) cut 1/4" off the edges of the bow and stern molds that come in contact with the strongback. It worked out just fine. If you take off too much just use shims to bring the mold back into the flush position.
Dave
I had the same problem with my F17. To make the stem flush with the station I simply (properly?) cut 1/4" off the edges of the bow and stern molds that come in contact with the strongback. It worked out just fine. If you take off too much just use shims to bring the mold back into the flush position.
Dave
"If given six hours to chop down a tree, spend the first four sharpening your ax." - Abraham Lincoln
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David James
- Posts: 223
- Joined: Tue May 11, 2004 9:04 pm
- Location: Glenview, Illinois
Wil, I'm, guilty of responding to your question without first having my coffee... :embarassed
You can't possibly move your molds. But it should be flush. In my case I eliminated the 1/4" of extra stem thickness by lowering the mold before I began planking.
sorry about the confusion.
Dave
You can't possibly move your molds. But it should be flush. In my case I eliminated the 1/4" of extra stem thickness by lowering the mold before I began planking.
sorry about the confusion.
Dave
"If given six hours to chop down a tree, spend the first four sharpening your ax." - Abraham Lincoln
David and ealger, thanks for the replys. My daughter and her boyfriend are building the canoe and they posted the original question.
I built the strongback and mounted the station molds for them. Actually the stems were proud by an eighth of an inch so I just belt sanded the inner stems for four inches adjacent to station six, refaired and the problem was solved.
If they hadn't completed fifteen strips on each side before we realized the the stems needed to be flush we would have reshaped the stem molds. The 3/4 " thickness of the inner stem is not a mandatory thickness, only the design. Both the inner and outer stems were bent from ash and the outer stem will be covered by a 3/8" brass stem cap so I don't think the slightly thinner inner stem for four inches will affect the over all integrety of the stems.
So far they have dond a very good job of stripping the hull. They will start the football tomorrow and I will help to trim the center line when the first half is completed, which should be tomorrow or the next day.
wil
I built the strongback and mounted the station molds for them. Actually the stems were proud by an eighth of an inch so I just belt sanded the inner stems for four inches adjacent to station six, refaired and the problem was solved.
If they hadn't completed fifteen strips on each side before we realized the the stems needed to be flush we would have reshaped the stem molds. The 3/4 " thickness of the inner stem is not a mandatory thickness, only the design. Both the inner and outer stems were bent from ash and the outer stem will be covered by a 3/8" brass stem cap so I don't think the slightly thinner inner stem for four inches will affect the over all integrety of the stems.
So far they have dond a very good job of stripping the hull. They will start the football tomorrow and I will help to trim the center line when the first half is completed, which should be tomorrow or the next day.
wil
Stems
Wil, some go to great pains to get the molds plumb in 3 axis only to discover that the one or more molds are not fair where one mold is proud by 1/8" and the next is shy 1/8". The tradgedy is that it's only discovered as the football is started.
When a builder reports having the stem 1/4" proud, or more, there is cause for concern. Sometimes the error is caused by how sharp the pencil was when transfering from plans, to templates to MDF to the band-saw to the sander. The cumulative errors get us!
The stem being proud by 1/8" near station 6 is not a problem and it's not necessary to grind it down before the strips approach that section. As the strips turn the bilge, the stem begins to take on the rolling bevel and will be shaped to produce a fair line with stations 4, 5 and 6. Most find that the stem will be shaped down to conform to the profile of station 6 at this point. On occation, the "extra" thickness of the stem is a blessing!
It's just a comfort to know why our building doesn't conform to the plans!
Keep us posted on your progress.
Ed...
When a builder reports having the stem 1/4" proud, or more, there is cause for concern. Sometimes the error is caused by how sharp the pencil was when transfering from plans, to templates to MDF to the band-saw to the sander. The cumulative errors get us!
The stem being proud by 1/8" near station 6 is not a problem and it's not necessary to grind it down before the strips approach that section. As the strips turn the bilge, the stem begins to take on the rolling bevel and will be shaped to produce a fair line with stations 4, 5 and 6. Most find that the stem will be shaped down to conform to the profile of station 6 at this point. On occation, the "extra" thickness of the stem is a blessing!
It's just a comfort to know why our building doesn't conform to the plans!
Keep us posted on your progress.
Ed...
Ed Alger
Just a quick progress report. Half the football has been stripped and the preliminary trim has been done. The final trim to the center line will be done tomorrow as well as initial fitting of the outer stems.
My daughter and her boyfriend are taking some friends into Yosemite and won't start filling in the other half of the football until they get back.
Like all first time projects, progress is slow, but many new skills are being learned. No major screwups to this point and the hull is looking good. More later.
wil
My daughter and her boyfriend are taking some friends into Yosemite and won't start filling in the other half of the football until they get back.
Like all first time projects, progress is slow, but many new skills are being learned. No major screwups to this point and the hull is looking good. More later.
wil
Progress report: 6/16/06
We just glassed the exterior yesterday. It was the first time any of us has worked fiberglass and it came out pretty good for a first attempt.
The finish as it sits has no runs or thin spots, but does have a wavy surface in places. There is enough resin over the entire hull that it will sand out just fine. We are just waiting for the resin to cure. We hope to be able to sand in four days. The interior should be glassed in six days.
The ash has been ripped for the gunwales and we will scarf joint it togrther. Premade seats, seat hangers and hardware, grab handles and a carry yoke were purchased from Ed's Canoe and all look great. So far this has been a wonderful experience with no major problems.
wil
We just glassed the exterior yesterday. It was the first time any of us has worked fiberglass and it came out pretty good for a first attempt.
The finish as it sits has no runs or thin spots, but does have a wavy surface in places. There is enough resin over the entire hull that it will sand out just fine. We are just waiting for the resin to cure. We hope to be able to sand in four days. The interior should be glassed in six days.
The ash has been ripped for the gunwales and we will scarf joint it togrther. Premade seats, seat hangers and hardware, grab handles and a carry yoke were purchased from Ed's Canoe and all look great. So far this has been a wonderful experience with no major problems.
wil
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davidb54321
- Posts: 214
- Joined: Fri Jan 28, 2005 7:05 pm
- Location: Presque Isle, Maine
- Contact:
Wil,
It sounds like you are enjoying this project. That is great! When you glue your gunwales up, be sure to allow unthinned epoxy to completely saturate the scarf joint area before you glue, then wipe off the excess and glue with thickened epoxy. Try not to clamp to tight or you will starve the glue joint.
Enjoy yourselves, you will be done before you know it!
It sounds like you are enjoying this project. That is great! When you glue your gunwales up, be sure to allow unthinned epoxy to completely saturate the scarf joint area before you glue, then wipe off the excess and glue with thickened epoxy. Try not to clamp to tight or you will starve the glue joint.
Enjoy yourselves, you will be done before you know it!
David Bartlett
"I don't fully understand everything I know!"
http://photobucket.com/albums/b81/davidb54321/
"I don't fully understand everything I know!"
http://photobucket.com/albums/b81/davidb54321/
The Prospector was launched about 20 minutes ago. My daughter and her boyfriend did a good job building considering that neither of them had ever worked wood before. They milled the strips from rough cedar, did all the bead and cove and made a canoe out of a bunch of "sticks".
It has not been varnished yet, but they leave for Alaska tomorrow and will varnish the canoe in northern California before heading north.
Our thanks to everyone who answered all of our beginner questions. Your help was greatly appreciated.
wil
It has not been varnished yet, but they leave for Alaska tomorrow and will varnish the canoe in northern California before heading north.
Our thanks to everyone who answered all of our beginner questions. Your help was greatly appreciated.
wil