my oars are too short

[rafafuti]

how could make my wooden oars longer
they are 72''
i need them to be 90''
any suggestion would be appreciated

[Richard Jones]

Well, they say that an epoxy joint is stronger than the wood itself. This would be a good test. Scarf in a piece, using a 1 to 8 ratio scarf. See if it can take the strain.

[Ian McColgin]

At the chandelry the oar streatcher is right next to the left handed exhaust bender.

[KAIROS]

At the chandelry the oar streatcher is right next to the left handed exhaust bender.

That Stretcher is too high-tech for me. I steam them, then put them on the rack. But then, I have heretical oars....special case.

[KAIROS]

Come to think of it though, isn't there some kind of a pump thing you can put on them that makes them longer?

Welcome to the Forum Rafafuti! There will be some more (real) knowledgeable responses soon.

[David G]

Alright... I think we may have all the joking responses out of the way now. The only time I saw someone try and make a set of oars longer, they scarfed in a section near the blades. They also put a small drift in (I'm remembering something like 1/4" diameter). It didn't work. The oars broke.

That's the only attempt I've seen or heard of. Based on that small sample, I'd suggest it's time to build or buy yourself some new oars. Save the shorter ones for another boat. Or sell them to offset the cost of the new ones. Or... you might find someone what wants to make the exact opposite swap (if you're far luckier than I've ever been).

And Terry... should we ask you how you know?? :p

[G.Sherman]

My "oars" are usually redheads.

[boylesboats]

how could make my wooden oars longer
they are 72''
i need them to be 90''
any suggestion would be appreciated

welcome to WBF...

Go get a oar stretcher... Then I'll show ya how it works

[Clinton B Chase]

how could make my wooden oars longer
they are 72''
i need them to be 90''
any suggestion would be appreciated

The time it takes to make a really excellent scarf joint (that won't break) and will keep things aligned, and not look obvious will not be worth it. It may take a little more time to make new ones, but you won't be worrying if they break (and you're in the middle of a lake!).

Clint

[Stan D]

Anybody ever seen an oar 72"? Seems way short to me. I know that's the dudes question, but that seems more like a slightly long paddle than any oar I ever saw.

[cjp1063]

Do you want practical or pretty? try to find a piece of aluminum tube that will slide (snugly) over the section to be scarfed, maybe 6-8 inches past, epoxy in place or a couple of screws. won't be pretty but it should help keep them in one piece.

[boylesboats]

When I build my Rowing Jon, I plan to build my own oars. The ones I have are not worth trying to improve.

Find some old Shoes for the leather or go with Poly of some kind.

If you did Scarf, it might help to glue a long strap on upper and lower of the Oar shaft. I scarfed sides and bottom of a McKenzie river drift boat Knock off.
There was plenty of stiffener so nothing failed.

Dont use any mechanical parts. Just wood and glue.

Old shoes? naaa... there gotta be a saddlery near ya.. if not.. leather still can be gotten at most boat chandleries.. good piece of saddle skirting work nicely if you can get them in 8 oz thickness

[NealmCarter]

Viagra

[rbgarr]

Stillettos.

[perldog007]

At the chandelry the oar streatcher is right next to the left handed exhaust bender.

No such thing as a left handed exhaust bender. Usually kept next to the spool of chow line and as as far away from the propwash as possible.

I like the scarf idea.

I would wrap it with glass cloth and soak that down good with resin as well. that's just me, an impressionable n00b.....

[jonboy]

Don't scarf in a piece, scarf an extension on... why have two joints...? If you can be bothered and are skilled enough, make a stepped scarf.....then rout out a channel maybe 15% the thickness of the shaft and let in a fillet. position the fillet on the side of the shaft that would theoretically be concave under flexing in the power stroke.
Personally I'd buy some new ones, or old ones at a boat jumble.

[cjp1063]

As a young private at my first post (Army) my first day at the motor pool I was sent to get a sample of diesel fuel, I was given a styrofoam cup. everyone was surprised when I returned with said cup still intact with the fuel in it. I guess they picked the wrong kind of styrofoam. Since that didn't work and I was too dumb to realize what was going on they then sent me down to another company to get a 1" philips head wrench. I returned with an offset philips head screwdriver. They gave up at that point...now changing the air in all of the tires from winter air to summer air was one of my favorites.

[cjp1063]

Sorry that had nothing to do with oars.

[Thorne]

It looks like everyone is assuming this is a troll of the Forum.

If the poster is serious we should see a reply of some sort. Like most here I'll recommend making new oars, as any sort of extension is going to be the weak spot where the oar would probably break. Extending spars has not worked for me at all, with two masts breaking at the extension in my past...

[boylesboats]

It looks like everyone is assuming this is a troll of the Forum.

If the poster is serious we should see a reply of some sort. Like most here I'll recommend making new oars, as any sort of extension is going to be the weak spot where the oar would probably break. Extending spars has not worked for me at all, with two masts breaking at the extension in my past...

maybe you're right Thorne...

Laminating loom may be one choice.. for all the trouble it worth.. I'd rather make a new pair, or purchase a pair

[Layzboy2011]

Just buy new ones, keep the old for a spare set.

[Yeadon]

Maybe he should keep the oars and get skinnier boat. And you guys thought you'd thought of everything.

[Candyfloss]

There was a thread a while ago that gave a formula for oar length that would have made the oars on my 8ft dinghy 10ft long! Obviously ridiculous. As specified by the designer, the oars are 6ft, but I suspect that this choice was influenced as much by convenience as anything else. 6ft oars fit inside the boat easily, & this is a yacht's tender. I think 7ft would work better.

[Thorne]

Thud - a quick search of the Forum will bring up more than you ever wanted to know about oar length.

What's a Rowing Jon, what waters will you row, and what sort of rowing (performance, 10 yards to the dock, or long and slow)?

Personally I prefer longer flexible oars over short stiff ones, but again that depends on the type of rowing you'll be doing.

I find the internal Wooden Boat Forum search engine to be pretty limited, as it doesn't allow Boolean searches (tow +dinghy +bridle).

Try Google's Advanced Search ( http://www.google.com/advanced_search?hl=en ) . Just copy and paste the Forum's URL ( http://www.woodenboat.com/forum/ ) into the last field named "Search within a site or domain:", then put in search strings like "tow dinghy bridle" or whatever.

[Candyfloss]

No, this can't be right.


Quote:
Shaw & Tenney Oar Length Formula for Correctly Fitted Oars

Inboard length of the loom equals ½ the span between the oarlocks + 2"
Total length of oar equals 1/7 of inboard length multiplied by 25
Leverage Ratio is 7:18
Distance from the center of leather to end of grip equals 7/25 of the total length of the oar


Thank you Ron Carter, for Shaw & Tenney link.
I think it is simple to make 7:18 ratio, taking the inboard available length as base.


The first item is clearly wrong. It gives an immutable overlap of four inches. What???
The last item is clearly wrong. The distance between the centre of the leather & the end of the grip is a function of the length of the leather! But much more importantly, it is a function of the distance between the rowlocks. And whether you like a gap or an overlap.

Now let's do the math.

My little dinghy is 8ft long & 4ft wide. The Formula is (4/2x1/7)x25
This gives oars at 7ft. Pretty good for my boat, but I suspect Thorne would find them somewhat inadequate on his (theoretical) 13ft rowboat with the same beam. He'd want something around 10ft. Or maybe (probably!) Thorne is much bigger & stronger than I am, & he wants 12ft. Which is what this formula & every other one I have found so far fails to address. Actually, it's possible that most rowboats are about 4ft wide. Narrower than that & you fit outriggers. Wider than that & you have a boat that's really hard to row. They should all have 7ft oars? I don't think so.

The leverage ratio is even worse. For a half-beam of two feet;
18/7x2/1=5ft!!!!
Is there something wrong with my math?

[Thorne]

I really don't think these formulas are worth much -- just see what the other builders/operators are using on the same boat on the same waters and go for it.

Remember that there is more than just length and width. An 4x8' boat could be a floating box with vertical sides, or a round-bottom boat with a lot of flare on the sides and a lot of overhand on both ends.

My 13.5' Chamberlain dory skiff may have an 11' waterline, probably more like 10.5' -- but my 14' Cosine Wherry probably has a 13'+ waterline. A guideboat actually has more waterline than gunwale length -- so again length isn't really a solid determining factor for oar length.

It also matters what waters you row (rough surf or flat protected water), how fast you wanna go, how much you wanna spend, and what style of rowing you wanna do -- overlapping handles, dory stroke, etc.

Another critical factor is storage -- if a pair of 6.5' oars will fit on the floorboards, but 7' oars will get seriously in the way or have to be up on the thwarts, then the shorter length may be a much better fit overall.

So get out on the water and see what others use and recommend. Email or call folks with the same boat design and find out what they use. Much more accurate (and fun) than some damn formula, right?

[rafafuti]

I went witha 20''piece of 1 1/2'' ID aluminum tube,3/16th'' wall. I will epoxy and a couple of screws. they seem to be balanced ok and they are very strong.
This was simple and easy fix
thanks for the suggestions all
ralph

[Clinton B Chase]

The Shaw and Tenney formula will give you are perfect oar length for a boat in average conditions, most of the time, and assuming no overlap on the pull. This formula is always my starting point. I have 9'1" oars for my boat. The ideal is to have 2 pairs of oars of oars, but if you only want one pair use the S & T formula exactly.

Clint

[Ron Williamson]

I extended a set of fir oars, eight or ten years ago.
IIRC,I added about two feet(gross) of 1 1/2" fir closet rod to the inboard end.
The scarfs are about 10-12".
They were used to propel a heavy, wide 10' fibreglass dinghy.
Crude as hell,but they haven't broken.
R

[Ron Williamson]

No leather.
Pinned oarlocks outboard of the scarf.
Some people can break anything.
R

[mobjack68]

you could just try more ballast...that will get you closer to the water..

[Bob Cleek]

Oars that are too short are like shoes that are too small... Buy a pair that fit.

[SamSam]

Change it to 'His oars are to short' would work like 'One brick short of a load' does.

[Vinny&Shawn]

[quote=rafafuti;2411495]how could make my wooden oars longer

Here is our solution with a simple clothespin scarf,for lengthening our boat hook by 24". I choose to use TiteBond 3 over epoxy. You should use what you are familiar with!!

http://i419.photobucket.com/albums/pp278/vgeorge1/boathook001.jpg?t=1260215888

http://i419.photobucket.com/albums/pp278/vgeorge1/boathook003.jpg?t=1260215983

http://i419.photobucket.com/albums/pp278/vgeorge1/boathook005.jpg?t=1260216028

http://i419.photobucket.com/albums/pp278/vgeorge1/boathook006-1.jpg?t=1260216059

[jgmarine]

Hi,
If not looking for aesthetics,
To gain 10" or so, you could install an aluminum, or SS sleeve, 16 Guage.

Jack

[Thorne]

Yabut - boat hooks and hoes have a real different range of flexion than a spar or oar.

My experience is that spars that flex will break right at the end a hard extension sleeve -- this happened to me with two 14' masts extended to 16'. Never tried it with oars but suspect that if the wood is flexible at all (like good spruce) you might see similar breakage.

[robm]

I once had two half oars which I scarfed together to make one whole oar. One was 2" diameter, the other 2.5", so there was some work with the plane to make it all pretty. It looked really good, so I got some spruce and made another oar to match, but no scarf this time. They both looked so good, I built a Gloucester Light Dory to try them out on.

So, you could say, I built my boat starting with half an oar....

And neither oar has broken. Epoxy on the lap. Plastic resin to widen the blades on the new oar.

[MaizieDerrick]

aloha.. my oars were too short on my 18 ft sea bright skiff, I had made them of the longest material i had at the time which was only 9 ft.. my solution to lenghten was to take a section of 4x4 and set the handle in one side and add round stock for the handle.. the reason for this is that as they now were 13ft they were to heavy on the outboard end.. now they are still a little heavy but manageable.. of course you can scale them down for yours but the priciple remains the same.. this is also the traditional look of oars for large pulling boats...derrick

[Vinny&Shawn]

I understand that the boat hook is a different tool but if the scarf is done properly and maybe add some fasteners,the scarf will have plenty of strength. Align the grain,it won't come apart!

[darroch]

I understand that the boat hook is a different tool but if the scarf is done properly and maybe add some fasteners,the scarf will have plenty of strength. Align the grain,it won't come apart!

Clothespin scarf - very nice. I've never seen one. Do you happen to have a pic of one or both of the pieces before gluing up? I could use that to advantage if one of my sprits ever snaps.

[KNOCKABOUT]

how could make my wooden oars longer
they are 72''
i need them to be 90''
any suggestion would be appreciated

I got a pair of 90's I no longer need. PM me.

[Vinny&Shawn]

Clothespin scarf - very nice. I've never seen one. Do you happen to have a pic of one or both of the pieces before gluing up? I could use that to advantage if one of my sprits ever snaps.

I don't have pictures of the stock ,but it was gotten out of an old mast from a 30'cutter built in Scotland,nice spruce. But the piece I started with was 1 5/8" square from which I cut the birds-mouth on a bandsaw. Then holding the new piece on the shank of the boathook(1 1/2"diam.),I scribed the male part to be fit. Using hand tools,took off the waste to about 1/4" of the line then with a nice Nielson plane took the wood to the line fitting by eye as I made progress, fun project.
I then glued the new piece on and after the glue dried,then proceeded to plane the square to round. First using a block plane then switching to a radius plane from my collection of wooden planes,sharp and slick. Remember to Orient the grain accordingly!!

[John B]

I had to lengthen some oars so I just pushed em though the table saw and 12 to 1 later... poifect.
Did it to a boathook too come to think of it.. nicked one of the workshop broom handles for the extra length.
I like to think we lost a broom but gained a very large scrubbing brush.

[EyeInHand]

Not sure if this will help, since they're squared, but I saw a set of these stretched oars recently at MASF this year. I just thought they looked nice when I took the photo. Wasn't til I got home I realized why they looked unique.

http://www.eyeinhand.com/Galleries/Albums/StMichaels-2009/source/image/_mg_8680.jpg (http://www.eyeinhand.com/Galleries/Albums/StMichaels-2009/source/_mg_8680.htm)