Teardrops n Tiny Travel Trailers

I've seen laminated interior beams on boats and love the look. So, I've decided to try and laminate some ribs for a galley hatch similar to the beams I've seen on boats. I took some 1/8" BB and cut it into 1.75" strips. I'm gonna laminate them into a rib about 1.5" thick. To minimize "spring-back, I've clamped the strips in a "jig" to get a "set" to them before actually gluing them all up.

Here's a picture of them clamped in the jig. The jig is just short pieces of 2X2 angle iron screwed to some plywood.



I can't seem to get the picture to be seen in this post. If you click on the image thingy and open it in a new tab you can see the picture. HELP!


More later.

Cheers,

Gus

Thanks for posting the picture. Any thoughts as to why it's not appearing in my post? Thanks, Gus

I glue lam'd my ribs, and there was no spring back at all when the glue dried and they came out of the jig. Mine aren't bent as tight as yours, so I used 7 layers of 1/4th inch strips. I did mine for the strength and they'll be covered, but they would have looked great exposed. I glue laminated 1/4 inch strips along the curved roofline to fill in between spars, too. It's a great technique that should serve you well.

Irmo Atomics wrote:I glue lam'd my ribs, and there was no spring back at all when the glue dried and they came out of the jig. Mine aren't bent as tight as yours, so I used 7 layers of 1/4th inch strips. I did mine for the strength and they'll be covered, but they would have looked great exposed. I glue laminated 1/4 inch strips along the curved roofline to fill in between spars, too. It's a great technique that should serve you well.

I used the 1/8" BB because it is inexpensive (about $5/sheet as I recall) and available. To buy, saw, plane (I have the machines necessary to to all) a nice clear wood would have been expensive. I looked around and even called the Gougeon/West Epoxy factory too find a source of pre-cut veneer like they use for cold moulding boats but had no luck.

The actual ribs will be far less radical than what is pictured but I'm over-bending the strips to give them a set before laminating them into a test rib. If I get no spring-back (as you did) I may make a second test rib w/o pre-bending/setting the strips to see if that step can be eliminated.

I also want to see if it works better with the form on the outside of the laminations or the inside of the laminations. Having the form on the outside with the ribs inside might result in a more accurate rib but having the form on the inside with the ribs outside might be easier to clamp the laminations to. Experimenting, fooling around, and learning is the fun part, ha.

Thanks for the input. I remain "optimistic".

Cheers,

Gus

Where are you getting BB for $5 a sheet?!?!? I am paying $23 a sheet for 1/8", 5'x5'.

Oldragbaggers wrote:Where are you getting BB for $5 a sheet?!?!? I am paying $23 a sheet for 1/8", 5'x5'.

I "lied" but unintentionally. It's been a while and it's now $13.85/sheet (contractor's price) at Far West Plywood in Northridge, California.

Still, cheap for the material to make cool looking ribs.

Cheers,

Gus

That's a great price!!

Luv those 'laminated' ribs but unless you're gonna leave 'em exposed they seem like an awful lot of unnecessary work to me. When building my TD in 2006 I searched to find the best 11-ply, cabinet grade 3/4" birch I could find locally. I clamped a piece of scrap MDX sheathing to the curve of the hatch walls, marked it & then cut a pattern for 2-inch ribs. I then cut 6 ribs (slightly oversize) from the 3/4" birch & after dry fitting I clamped 'em all together for simultaneous sanding & final shaping. I used pocket holes to attach cross bracing & end pieces. After gluing all together I 'jigged' & braced the frame on a flat surface 'til glue cured then added 2 layers of 1/8" Luan before installing the hatch. I had absolutely NO springback problems. While my hatch doesn't have as short a radius as some I've seen, it does have a pretty good curve. I used the TD for nearly a year with hatch ribs exposed (galley unfinished) before adding the 'beadboard' as a liner. I use homemade wood 'props' for support so perhaps lack of pressure from gas struts may also contribute to its stability. I've done lots of woodworking but had no previous experience with this type of build. I'm pretty well convinced b y results of this job that a hatch constructed from well selected, stable materials should exhibit little or no springback problems...

I used cabinet grade birch ply also, and left them exposed.




However, I really like Gus' plan. You can make some pretty neat curves using his method, and then there's the value of the experience, which is, as we all know from having built a teardrop, priceless.

Sometimes it's not just about getting to your destination, it's also about the journey. I wanna laminate some ribs, ha.

Yup, I plan on leaving them exposed.

Stay tuned.

Cheers,

Gus

eamarquardt wrote:Sometimes it's not just about getting to your destination, it's also about the journey. I wanna laminate some ribs, ha.

Yup, I plan on leaving them exposed.

Stay tuned.

Cheers,

Gus

That's all the reason needed!

After a number of "distractions" I got back to laminating my "test" rib for my galley hatch. The results exceeded my expectations.





Key learnings:

1- The rib is verrrrrrrrrrrry stiff.
2- Absolutely no springback when removed from the jig.
3- A bit of glue got on the face that will be exposed and discolored it. Covering the exposed faces with masking should solve this issue.
4- I used vice grip clamps to clamp the glued up rib to the angle iron jig brackets (about 6" center to center) and spring clamps in-between the the vice grips. I got
about .030 variation in thickness (not that it matters) along the length of the rib. Using C-Clamps rather than spring clips will probably reduce this.
5- The rib is 5' long but longer ones could be made by staggering the plys.
6- I used tightbond 2, laid on a generous bead with a squeeze bottle and rolled it out with at small sponge roller.
7- I wrapped it in plastic to contain the mess but next time I'll just put plastic down on the plywood form draping it over the angle iron brackets to prevent sticking.
8- Belt sanding the edges worked well but I may make a jig to hold my router and route the exposed edges down just a tad to get an exact thickness. Why, because I can.
9- Most of the bend caused by the "preforming" didn't last. No need to pre-bend the ribs prior to laminating.
10- The little angle iron brackets were not exactly square with the base of the jig so I tweaked em to be square with world before I laminated the rib.

To Infinity and beyond or at least the count of ten.

Cheers,

Gus

Nice work, Gus!

biziedizie wrote:Any laminated arches and bends I make I steam them. There's no spring back and everything works out perfectly.

Yup but ya gotta build a steam box and a steam generator. Solid lumber is expensive compared to 1/8" ply (the rib had less than $7 worth of materials in it).

The rib and laminations will match the exposed edges of the BB plywood elsewhere.

That's my story and I'm sticking to it.

Cheers,

Gus