need some advice on making cedar laminate blades

[picmacmillan]

i would like to ask anyone with the knowledge to make some of those blades that are on the danbuilt...i think they are very sharp...my questions are

• what kind of cedar(does it matter)?
  
• how thick were the pieces of boards used?
  
• what type of glue was used?
  
  

-what was used as a coating (linseed oil)?

-how many pieces were used to laminate(per blade)?

-do they have to be planed? or a jointer used?

• what were the finished dimensions of the blades?(thickness at tips and root), as well as the width of the blades, also at the tip and the root.
  
• I believe dan has said in the past that the blades are 1/8" as thick as they are wide?
  
• i believe dan said the blades are cut from a 1x6(in half, lengthwise), and then glued so as the width is 3" thick.?
  
• i have found some 5/4 cedar?...is this what was used? or just 1"?
  
  

sorry for all the questions in a row...i am hoping a few sentences will give me the information i need...thanks in advance...happy easter...pickster

[newguy]

ive never done a laminate blade

but i dont think it would be too hard

what i would do if i had access to a reasonable wood shop

that has a tble sw and jointer and planer

i would cut 2 inch wide strips that are how ever long you

want of cedar, red cedar ?   any marine glue would work

yellow glue would i bet hold up as long as the blades were sealed well

just glue the 2 inch wide by 34 thk together till you get a desired width

like six or 8 inches and then just plane the glue up for square edges and

start carving

what i was thinking to seal the blades is boat sealer or just paint them

i think paint would even last quite a few years before  one would need to repaint them but danb and others have know more

[mvr]

An earlier thread had some comments about laminated blades including some bibliographic sources for wood information.  I posted on it about 3 to 7 days ago, so it should be easy to find.

best,

Mark

[Chagrin]

Type of cedar: Not red cedar (like would be used in a closet). Basically, use the type of cedar you'll find at the lumber store. Select those boards with the tightest grain, and when gluing up, make sure the grain all runs in the same direction for the best stability.

Glue: I'd recommend "Titebond II" as it's commonly available and weatherproof. It won't withstand continued submersion but will most certainly handle the elements. I've used it to build paddles and it's held up without issue.

Finish: An exterior polyurethane varnish ("Spar varnish") will do. Linseed wouldn't give you the toughness you need.

Planer/Jointer: Not necessary but handy -- the table saw will give you good glue joints alone. What would be more important is the clamping strategy used when gluing up -- you can (almost) never have enough clamps! Go ahead and make a test glue joint with some scrap, let it dry, and try to break it apart to test its strength.

Also, "5/4" describes an unplaned board that would normally be planed to a final 1" thickness. Do NOT glue rough surfaces together.

[bobn]

 question of pitch revisited. windmills vs aircraft props blade angle geometric pitch design pitch ,observed pitch?? any responce??

[Cat23]

Type of cedar: Not red cedar (like would be used in a closet). Basically, use the type of cedar you'll find at the lumber store. Select those boards with the tightest grain, and when gluing up, make sure the grain all runs in the same direction for the best stability.<p>
Glue: I'd recommend "Titebond II" as it's commonly available and weatherproof. It won't withstand continued submersion but will most certainly handle the elements. I've used it to build paddles and it's held up without issue.<p>
Finish: An exterior polyurethane varnish ("Spar varnish") will do. Linseed wouldn't give you the toughness you need.<p>
Planer/Jointer: Not necessary but handy -- the table saw will give you good glue joints alone. What would be more important is the clamping strategy used when gluing up -- you can (almost) never have enough clamps! Go ahead and make a test glue joint with some scrap, let it dry, and try to break it apart to test its strength.<p>
Also, "5/4" describes an unplaned board that would normally be planed to a final 1" thickness. Do NOT glue rough surfaces together.

hi why not glue rough surfaces togeather, too late for me as this is what ive done also does anyone know about polyester resin as my mixes will not cure , still tacks after 36 hours temp about 14 c, 2 % hardener mixed

[Frank S]

hi why not glue rough surfaces togeather, too late for me as this is what ive done also does anyone know about polyester resin as my mixes will not cure , still tacks after 36 hours temp about 14 c, 2 % hardener mixed

 the bond of glue works best the smoother and tighter you can get the joint, A perfect glue bond would be only 1 molecule thick but that is just about impossible.

[dbcollen]

You guys dug this one up from 2005, maybe rover will reply and then go re-bury this old bone 

[mad_labs]

I have made only one set of laminated blades but I have laminated wood for marine projects.

Run the wood through a planer and joiner. Doing this first makes the rips better.
Rip into strips, size depends on blade length.
Run cut edges through joiner. make sure they all come out exactly the same.
Weigh the strips. Play mix and match until the stack for each blade comes out as close as possible to the same weight. Easier blade balancing later.
Alternate grain on the strips when gluing.
I use two part epoxy like west systems.
Lots of clamps. Not too tight, as you can cup the blanks. Just tighten until glue stops oozing.
Use wax paper to glue on. It will stick to the wood some but won't bleed through to your bench.

Start carving!

Jonathan

[fabricator]

A seven year old thread? You gotta be kidding me.

[tecker]

Urethane glue soaks up resin good . You can use Acetone to make the wood hard as nails 4 to 1 Acetone to poly Resin and mix catilist as if it were total resin

[birdhouse]

old thread sure.  but might be a good place to get good info. 

i laminated my 8.5' dia prop.  used clear fir.  my blanks were roughly 2.5" x 9" and made up of 8 pieces per blade in two layers with seams staggered.  i used gorrila glue.  i glued the top and bottom separate, then ran each portion through the planer, then glued them together.  for finish, i filled divits with west systems, and filler.  one layer of 6oz fiberglass cloth, then three layers of 2 part epoxy paint, then a final coat of krylon rattle can. 

i serviced my mill this past summer after a year of use, and the blades looked identical to when the mill was installed. 

some pics of what i did:







and the mill running if anyone cares to watch...

http://www.youtube.com/user/boschme?feature=mhee 

adam

[tecker]

The directions on the urethane glue wants you to wet the bond area before applying the glue . This step makes a smoother coverage and tighter bond for sure .

[birdhouse]

yea, i did wet the boards before.  seems to give better penetration of the glue.  gorilla glue is pretty fantastic!  aside from the excess spooge out, (which i planed off) i have been very pleased with the product!

adam

[fabricator]

Wetting is intended to start a capillary action which pulls the glue into the wood, that's is why clamping and tight joints are so important, so there's nowhere else for the glue to go but into the pores.

[tanner0441]

Hi

Wetting with water also supplies the PU with a source of oxygen to help the resin in cross linking.

Brian.