Replies

1. 
   davcefai | Jun 24, 2009 07:59pm | #1

   I wouldn't be too sure that tiller handles fail because of UV exposure. There can be tremendous stresses on a tiller (upwind in a strong wind a boat has a strong tendency to turn into the wind - it's called luffing) and it could well be that the "waggling" of the tiller causes a glue failure.

   I could understand an epoxy coating failing but a glue-up is not exposed to light except at the edge.

2. 
   JohnWW | Jun 24, 2009 08:19pm | #2

   I would be inclined to skip the adhesives and just pin the joints, that way they can be disassembled in the future if repairs need to be made, in case the leg bottoms rot out for instance. Draw bolts would be another good choice.

   I agree with the earlier post, I don't see how UV could cause a glue failure.

   John White
   Shop Manager for FWW Magazine, 1998-2007

3. 
   KeithNewton | Jun 25, 2009 12:35am | #3

   The epoxy will be as strong as the resorcinol until the temprature gets up to 200º.

   Epoxy doesn't need clamp pressure, if you glue both halves of a joint and they are in contact with each other. However Resorcinol needs very high clamp pressure to achieve maximum strength.

   Most tillers that I have seen fail, were due to not keeping the finish up, that allowed moisture to get into the wood, which was usually ash and teak, which then move to different ratios.

   The UV problem with epoxy is only relative to using it clear as a finish. UV doesn't penetrate the joint to hurt it for your need. It is much easier to use, and is not hurt by moisture.

   You can buy West brand if you like, but I have not had any problems with the brand that I use for less than half the price, and the 1 -1 ratio is very forgiving, while the 5 -1 of West is not so.

   Here is a link to the brand that I use. http://fgci.com/

4. 
   roc | Jun 25, 2009 04:52am | #4

   >until the temprature gets up to 200º

   DP,

   Apparently Keith knows something about the weather patterns in your back yard that we don't. 200º ? are ya on Mars or what ?

   : )

   roc

   Give me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )

1. 
   saschafer | Jun 25, 2009 04:08pm | #5

   I don't think Mars ever gets that hot. It's an everyday occurrence on Venus, however.

   -Steve

    

5. 
   DickPutz | Jun 25, 2009 09:32pm | #6

   Thank you all for the valuable feedback.

   You never know where things will lead when you ask a question--part of the great value in these forums.

   Anyway, I've decided to go with John White's suggestion: forget glue altogether and pin the joints. 

   I'm familiar with this technique but have been too chicken to actually do it. I have used draw bolts before to build a very heavy work bench using Lee Valley's purpose built knock-down bolts and was very pleased with the results--its rock-solid.  But in this case I didn't want to spend the money.  Anyway, after building the frame and cutting out all the joints and then fitting it dry, I impressed myself with how tight it is.  So pinning the joints (especially given the fact that this will go outdoors now and the joints will swell and further tighten) should work very well.  And I like very much John's point that pieces can be replaced in the future. 

   I have one question though:  the bench frame is red cedar, so what type of peg should I use?  (I'm thinking cedar?)

   Thanks for the other info about epoxy and resorcinol though.  If I was going to glue I would use epoxy because cedar is soft and I would likely need some gap-filling characteristics that resorcinol doesn't offer.  I was surprised though after researching a number of boat builder sites how waterproof epoxy isn't.  E.g. http://www.landlpardey.com/Tips/graphics/2009/June.pdf

   But I'm sure it would be fine in this application.

    

    

   
   

   ---

   Edited 6/25/2009 2:34 pm ET by DickPutz

1. 
   davcefai | Jun 26, 2009 08:10am | #7

   You need to bear in mind that "epoxy" covers a range of products which can be tailored for different purposes.I have met an Italian contractor, a specialist epoxy flooring supplier who had his yacht built from epoxy he supplied rather than the usual polyester fibreglass. He had to sign a waiver exonerating the builder from any responsibility for structural failure.Last I heard he hadn't drowned yet.Incidentally, when you talk epoxy with the specialists have the headache pills available. If nothing else, the range of choices can be bewildering.

2. 
   DickPutz | Jul 04, 2009 12:20am | #11

   Just re-printing a question hidden in one of my earlier posts above:

   I have one question though:"  the bench frame is red cedar, so what type of peg should I use?  (I'm thinking cedar?)"

   These joints will definately be swelling and contracting with the seasons outdoors.  So should it be the same wood or a hardwood?

   Any suggections?

   Edited 7/3/2009 5:21 pm ET by DickPutz

1. 
   JohnWW | Jul 04, 2009 08:15pm | #12

   Being the length of the peg is cross grain to the leg you can't match the movement, the peg will stay the same length no matter what, and the diameter shrinkage of something as small as a peg is too minor to worry about. I'd use a hardwood for strength and ease of driving.John White
   Shop Manager for FWW Magazine, 1998-2007

1. 
   WillGeorge | Jul 06, 2009 11:16am | #13

   Sir I agree..

   Maybe a stupid idea, but I messed up on cutting tenons for the head and foot boards of my two Chinese style canopy beds. Eight boards! Yes, each is two parts... Very stupid of me! But I do stupid stuff every day... Not only with woodworking!

   I glued new extensions onto the existing (short) tenons and after the glue set a day or two I put two dowels into each tenon (with new wood of the same type) that went down into the base wood. No glue on the pegs. Here in Chicago the humidity and temp. changes by the hour..  I have seen no movement of the pegs or the tenon width from the pegs... I was mostly looking for spliting of the tenons along the width next to the new pegs I put in. I see nothing..

   Edited 7/6/2009 4:17 am by WillGeorge

6. 
   7Joel | Jun 27, 2009 11:14pm | #8

   Just a word about the longevity of Resorcinal glue. I build a canvas covered kayak 33 years ago with sawn frames glued with it -- still holding! It does have a bit of smell when you mix it up -- or it did back then.

1. 
   DickPutz | Jul 02, 2009 07:08pm | #9

   That is great testimony!  And I have heard similar stories from others.

   In future, if I do anything that's long term outdoor I will go with resorcinol.

1. 
   Jimma | Jul 03, 2009 09:28pm | #10

   Just to add that, I used resourcinol to assemble an eight-foot exterior door made from two plywood panels and 2X4 pine framing in a sandwich. That was 43 years ago and there's been no sign of warping or delaminating. Great stuff, but cures slower than Titebond or epoxy and it leaves a glue line (which doesn't show if it's next to dark wood).