Glen or Bryan
I believe both of you have seen and/or built the Sairy Gamp, by Rushton.
While lofting the numbers from this plan.. I'm getting some confusing results.
Form 4, center form, I'm getting a flair in the gunnal.. Form 3 also, but less severe. However, the numbers on Form 2 are showing a VERY severe slant inward. My guess is that on the last number, which is at 9 7/8" from baseline, is incorrect. At 9" from baseline, the width is 11-". At the gunnal line, 9 7/8", the width is only 10 1/2".
That doesn't make sense...
Form 4 has a lot of flair outward.
Form 3 has less flair.
Form 2, if I change the bad number to 11 1/2", then the flair is again more severe than Form 3.
Form 1 has almost no flair,
It seems to me that Form 2 should have less flair than Form 3, so I don't know what that number should be.. ??
You guys have any idea.. ??
Rehd
Lofting Sairy Gamp... Issues..?
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Rehd Brown
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- Location: Fresno, California
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Glen Smith
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- Location: Baie-St-Paul, Quebec, Canada
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Bryan Hansel
- Posts: 678
- Joined: Fri May 14, 2004 6:36 pm
- Location: Grand Marais, MN
- Contact:
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Rehd Brown
- Posts: 148
- Joined: Sat Sep 08, 2007 8:23 pm
- Location: Fresno, California
lofting/drafting
What you need to do is really loft this design. What you are doing is drafting the stations from the offsets. A full size lofting of all the lines and offsets will allow you to fair out the bad numbers. The good thing is that you are lofting a very small and symmetrical hull. Being symmetrical you really only have to loft half of it, so it will fit on the 4x8 sheet of plywood that you will get your molds out of later. I would probably loft from station 3 on one end through ther center to the other end. This would get the curves about the center of the hull(station 4) right.
I would suggest lofting the hull without deducting fot plank thickness. When you get the lines fair then deduct the plank thickness. Don't forget that you cannot simply deduct 5/32" for plank thickness. The offset lines intersect the plank at an angle, so each deduction will be different.
I drafted the stations for the UGO from the book and had no problem with them except figuring out the deductions
I would suggest lofting the hull without deducting fot plank thickness. When you get the lines fair then deduct the plank thickness. Don't forget that you cannot simply deduct 5/32" for plank thickness. The offset lines intersect the plank at an angle, so each deduction will be different.
I drafted the stations for the UGO from the book and had no problem with them except figuring out the deductions
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Rehd Brown
- Posts: 148
- Joined: Sat Sep 08, 2007 8:23 pm
- Location: Fresno, California
Thanks
The numbers I have are all that I can use and they are taken off the original planked boat. I have to make due here. I have all the half-molds drawn on one sheet of drawing paper and I can see the probable pattern that SHOULD be taking place. The one number in question is just so totally out of whack that it's very obvious. I don't have a boat to compare to, nor drawings, to see exactly what the boat looked like. I've seen the factory site with a boat, and I've seen the boat on Bryan's site, but all are distant shots..
As for the plank thickness and lofting for the forms only... I'd thought of that. Lofting off of the planking alone would give me a faceted mold.. These deminsions are taken at 1" intervals until they reach the gunnal. I have to assume they were just averaging or taking measurements off of the centers of the planks..?? Not sure.
It would be different for doing strips instead of bigger planks anyway... so I'm just taking an average off of what I have, less 1/4" for my strip thickness. That will get me very close, but probably not perfect.!
I lofted on the drawing board first ( because I have a surplus of paper and pensils ) and after checking to see if all's well, then I put it to plywood.
The fun will be removing the keel / keelson and making the end forms with inner stems...
This is my first attempt at this sort of thing.
All that being said, I'm not really looking for an exact duplicate. I'm just trying to build a fun canoe for a stack of 10' strips and this boat was brought to my attention. My design skills are limited so I'm just lifting measurements from someone elses work. It appears there are a couple of errors, although minor, and will need to be adjusted.
I was hoping Bryan could tell me if the hull actually has a slight flair in the gunnal.
The fact that all the offsets seem to indicat this is probably my answer. I just need to clean up the one form number and get it right.
Rehd
The numbers I have are all that I can use and they are taken off the original planked boat. I have to make due here. I have all the half-molds drawn on one sheet of drawing paper and I can see the probable pattern that SHOULD be taking place. The one number in question is just so totally out of whack that it's very obvious. I don't have a boat to compare to, nor drawings, to see exactly what the boat looked like. I've seen the factory site with a boat, and I've seen the boat on Bryan's site, but all are distant shots..
As for the plank thickness and lofting for the forms only... I'd thought of that. Lofting off of the planking alone would give me a faceted mold.. These deminsions are taken at 1" intervals until they reach the gunnal. I have to assume they were just averaging or taking measurements off of the centers of the planks..?? Not sure.
It would be different for doing strips instead of bigger planks anyway... so I'm just taking an average off of what I have, less 1/4" for my strip thickness. That will get me very close, but probably not perfect.!
I lofted on the drawing board first ( because I have a surplus of paper and pensils ) and after checking to see if all's well, then I put it to plywood.
The fun will be removing the keel / keelson and making the end forms with inner stems...
This is my first attempt at this sort of thing.
All that being said, I'm not really looking for an exact duplicate. I'm just trying to build a fun canoe for a stack of 10' strips and this boat was brought to my attention. My design skills are limited so I'm just lifting measurements from someone elses work. It appears there are a couple of errors, although minor, and will need to be adjusted.
I was hoping Bryan could tell me if the hull actually has a slight flair in the gunnal.
The fact that all the offsets seem to indicat this is probably my answer. I just need to clean up the one form number and get it right.
Rehd
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Bryan Hansel
- Posts: 678
- Joined: Fri May 14, 2004 6:36 pm
- Location: Grand Marais, MN
- Contact:
It just occured to me that Dan Miller at http://dragonflycanoe.com/ may have lofted this canoe before. You should drop him a line.
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Rehd Brown
- Posts: 148
- Joined: Sat Sep 08, 2007 8:23 pm
- Location: Fresno, California
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Rehd Brown
- Posts: 148
- Joined: Sat Sep 08, 2007 8:23 pm
- Location: Fresno, California
Bryan & Others
I got a response from Dan Miller, of Dragonfly Canoe Works, this morning. He says the numbers, as written by O.E. Markkula, are flawed. I believe his words were "Fraught with Errors & Problems". So, as I wrote back to Dan, I will continue with the lofting, and when things don't look right, I'll go with "Gutt-Feelings" and do what looks good ( and works ).
I guess when it's done, it'll be more of a Sairy Gump, but as long as it flaots.. The G-kids will have fun in it. That's what counts.
I will make a second, with modifications in length, width and height, so the kids can grow with it..
Their paddles are already made, so I need to get going before they start using them to impale each other.. :shocked
Thanks for Dan's info. Bryan.. That was a big help.. Now, I can go on and not worry about all the odd-ball lines that come up..
Rehd
I got a response from Dan Miller, of Dragonfly Canoe Works, this morning. He says the numbers, as written by O.E. Markkula, are flawed. I believe his words were "Fraught with Errors & Problems". So, as I wrote back to Dan, I will continue with the lofting, and when things don't look right, I'll go with "Gutt-Feelings" and do what looks good ( and works ).
I guess when it's done, it'll be more of a Sairy Gump, but as long as it flaots.. The G-kids will have fun in it. That's what counts.
I will make a second, with modifications in length, width and height, so the kids can grow with it..
Their paddles are already made, so I need to get going before they start using them to impale each other.. :shocked
Thanks for Dan's info. Bryan.. That was a big help.. Now, I can go on and not worry about all the odd-ball lines that come up..
Rehd
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Rehd Brown
- Posts: 148
- Joined: Sat Sep 08, 2007 8:23 pm
- Location: Fresno, California
Saturday Afternoon and takin' a break from cleanin' up the place... My Spring-cleaning!
I got the half forms all drawn for the Sairy Gamp. I had to make corrections to true up the curves on every form. Drawing up the numbers as they are came out all Zig-Zagged.
With this set of numbers, there's no way of telling if it's a 'True Lofting' but with all the alterations being less than 1/4" ( except one... over an inch off ), I think it will be pretty close. The end-forms are on the drawing board at the moment, but I want to cut out the other forms first and set them up before I finish the end forms. This is my first time doing this and I'm not exactly sure how the end-form and form #1 are supposed to meet. I have it temporarily drawn up, by their numbers, but need to adjust for the 1/4" strip thickness and the height off of the workbench. I'm sure it will be O.K. but just want to double-check before cutting up some plywood.
I need to put my router table together to run a dado around the forms for my clamps and I'll be ready to go.
I think I'll be cutting out forms on Monday.
Rehd
I got the half forms all drawn for the Sairy Gamp. I had to make corrections to true up the curves on every form. Drawing up the numbers as they are came out all Zig-Zagged.
With this set of numbers, there's no way of telling if it's a 'True Lofting' but with all the alterations being less than 1/4" ( except one... over an inch off ), I think it will be pretty close. The end-forms are on the drawing board at the moment, but I want to cut out the other forms first and set them up before I finish the end forms. This is my first time doing this and I'm not exactly sure how the end-form and form #1 are supposed to meet. I have it temporarily drawn up, by their numbers, but need to adjust for the 1/4" strip thickness and the height off of the workbench. I'm sure it will be O.K. but just want to double-check before cutting up some plywood.
I need to put my router table together to run a dado around the forms for my clamps and I'll be ready to go.
I think I'll be cutting out forms on Monday.
Rehd
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Glen Smith
- Posts: 3719
- Joined: Sat May 08, 2004 9:08 am
- Location: Baie-St-Paul, Quebec, Canada
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Rehd Brown
- Posts: 148
- Joined: Sat Sep 08, 2007 8:23 pm
- Location: Fresno, California
Hey All
Sorta got the day off today.. ( had some skin cancer removed from the knoggin..)
I'm finished drawing up the station molds and about done with the stem forms.. and I just wanted to get an idea from you guys that have been through this before..
The form is drawn, it attaches to the #1 station, even with the very tip of the station. So, I have the ^ shape of the station meeting with the flat edge of the plywood stem form. The inner stem starts approx. 7" away.
My question: Is it necessary to keep the stem form solid between the actual inner stem and the #1 station form. I would have to bevel it to match the ^ at the top.... but the strips don't attach to it... so, could I just lower the stem form in that area and eliminate the extra work... ? The strips would leave the #1 station and next touch the inner stem where they would be glued. I don't plan on using staples so I'm thinking I could cut this little section out and not mess with any bevels, tape or anything..
Think I'm gonna go take some tylenol... two by mouth and grind one up and put it under the bandage..!!! :shocked
Putting drawings to plywood this weekend...
Rehd
P.S. Glen... you expressed interest in this project.... would you like the numbers I ended up with on these forms.?
Sorta got the day off today.. ( had some skin cancer removed from the knoggin..)
I'm finished drawing up the station molds and about done with the stem forms.. and I just wanted to get an idea from you guys that have been through this before..
The form is drawn, it attaches to the #1 station, even with the very tip of the station. So, I have the ^ shape of the station meeting with the flat edge of the plywood stem form. The inner stem starts approx. 7" away.
My question: Is it necessary to keep the stem form solid between the actual inner stem and the #1 station form. I would have to bevel it to match the ^ at the top.... but the strips don't attach to it... so, could I just lower the stem form in that area and eliminate the extra work... ? The strips would leave the #1 station and next touch the inner stem where they would be glued. I don't plan on using staples so I'm thinking I could cut this little section out and not mess with any bevels, tape or anything..
Think I'm gonna go take some tylenol... two by mouth and grind one up and put it under the bandage..!!! :shocked
Putting drawings to plywood this weekend...
Rehd
P.S. Glen... you expressed interest in this project.... would you like the numbers I ended up with on these forms.?
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Glen Smith
- Posts: 3719
- Joined: Sat May 08, 2004 9:08 am
- Location: Baie-St-Paul, Quebec, Canada
I would either extend the inner stem all the way to the first form or shape the unused portion of the stem form so the strips land on it just like on the inner stem. Apply tape to this portion so the strips don't stick to it. If you use outer stems, don't forget to make them about 1" shorter than the inner stems at the inboard end so you don't create a hole through the hull when you make the mortice for the outer stems.
Yes, I would appreciate receiving the new numbers. That would save me some time if I ever get around to building one myself. Take care of your health.
Yes, I would appreciate receiving the new numbers. That would save me some time if I ever get around to building one myself. Take care of your health.
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Rehd Brown
- Posts: 148
- Joined: Sat Sep 08, 2007 8:23 pm
- Location: Fresno, California
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Rehd Brown
- Posts: 148
- Joined: Sat Sep 08, 2007 8:23 pm
- Location: Fresno, California
Hey Glen and all...
I finished the drawings of the half molds, converted them to full station drawings and then put them to plywood.
I was going to get the numbers all down and make an excel document to put them all together, but about a week ago, I was rear-ended while on my route, in the postal vehicle. Got twisted around pretty good and have been pretty much off work since.. Just doing a couple hours a day in the office. Can't drive yet as I'm on some nifty meds.. and the head is a bit groggy. I should be good to go this week... Hopefully!
I did some work on it the past couple of evenings and got the excel sheet started. I've got the numbers all ready, just have to put them on the sheet.
I also have the half mold drawings and the full station drawings. Once I get my stations all cut out and dado'd, I'm going to give the paper-work away.
I'll have the numbers I can send you via email, but if you or anyone else wants the paper patterns, let me know and I can mail them off any time. I won't need anything but the plywood station molds. I drew them with a little extra material so I can build a second boat with all the gunnal numbers raised about two inches and stretched to around 9 1/2 to 10 feet.
Let me know and I should be able to get stuff in the mail in a few days.
Rehd
I finished the drawings of the half molds, converted them to full station drawings and then put them to plywood.
I was going to get the numbers all down and make an excel document to put them all together, but about a week ago, I was rear-ended while on my route, in the postal vehicle. Got twisted around pretty good and have been pretty much off work since.. Just doing a couple hours a day in the office. Can't drive yet as I'm on some nifty meds.. and the head is a bit groggy. I should be good to go this week... Hopefully!
I did some work on it the past couple of evenings and got the excel sheet started. I've got the numbers all ready, just have to put them on the sheet.
I also have the half mold drawings and the full station drawings. Once I get my stations all cut out and dado'd, I'm going to give the paper-work away.
I'll have the numbers I can send you via email, but if you or anyone else wants the paper patterns, let me know and I can mail them off any time. I won't need anything but the plywood station molds. I drew them with a little extra material so I can build a second boat with all the gunnal numbers raised about two inches and stretched to around 9 1/2 to 10 feet.
Let me know and I should be able to get stuff in the mail in a few days.
Rehd