Hatch spars.

[dales133]

Wondering what most of you use for hatch spars.
I'd personal prefer timber to ply preferably.
What size stock did you use and what would the experts zest.
Cheers dale

[backstrap bandit]

I prefer plywood because it is more stable as far as expansion and contraction than solid wood and also less spring back issues u just have to double it up

[tony.latham]

I really like poplar. It's stable, lightweight, and grabs screws and crown staples like glue. I make my hatches using 2" by 3/4" spars.





Note the side gussets in the above photo that are 4" at the center and taper back to 2" on the ends. No springback. (That's Steve Fredrick's method from his build manual)





T

[DMcCam]

Ditto with Tony on the poplar spars and plywood for ribs. My spars are 1x2's (3/4" x 1 1/2").



Best,

Dave

[dales133]

Thanks guys.i plan on leaving the hatch unsigned on the inside so I'm going for a good looking finish.
I'm also getting my ribs CNC'd as it will save a ton of time and frustration and I can get it done cheaply.
I may even make laminated ribs with ply and timber.
With the generic benroy aproximatly what width stock would I require to get the hatch ribs cut in one piece or does anyone join them?
Regards dale

[halfdome, Danny]

I use 1/2" Russian/Baltic Birch plywood.
I use Red Oak at the top and bottom ends of the lid for screws, IE hurricane hinge.
I double up the spars on the ends for the gas strut screws to bite into.
My cross pieces are any 3/4" plywood on hand and I use lots of pocket screws where my nail gun won't reach.
My spacing is 6".
I use 3/4" blocking for tail lights, license plate/light, galley lid light, back up light & paper towel mounting.
To make sure everything comes out perfectly square I put 6" x 6" blocking at all corners.
Danny

[ctstaas]

Hi Dale,
I made my hatch frame out of one inch square tubing rolled and welded. One technique I've used successfully for rolling multiple pieces the same is to roll all of them close first. Fit one piece perfectly to specification and then fit the others to the first part. I find I can control variation between parts better this way. I used four vertical bows for my hatch. I used 1/4" plywood to cover. On the inside of the plywood I cut kerfs across the width through two of the three layers approximately one inch apart so it would bend easy around the frame. On three sides of the exterior perimeter I pop-riveted 2" by 1/8" Al flat stock. I made my support from 1/2 Round steel welded to a Tee and rolled to fit the interior contour of the frame. As the hatch goes up the Tee rotates in a sheet metal bracket welded to the frame, the dumb end of the rod drags up the shelf and find a receiver made of pipe and sheet metal screwed to the shelf with a safety pin attached with a sash chain. The pull handle is stainless steel rod plug welded to SS mounting brackets and is the base for my lantern holder when raised. I got my hurricane hinge from Grant Whip. If I have the chance to do it again I would make dueling support rods with a round stock connector to make them work together at the same time. still need to skin the outside with Al or not? but am OK with not. Pictures are on page 25 of the "C""s in the gallery.
Enjoy, Chris

[dales133]

Some interesting ideas.have you got pictures of the steel hatch.
And how much does yours weigh danny

[ctstaas]

Hi Dale,
I figured it out, where/how to find my pics. Click on gallery and about half way down that page is a ribbon for users albums. On page 16 of the "c"s are photos of my hatch and stuff.
Enjoy, Chris

[dales133]

Cool thanks!

[KCStudly]

... or just click on the camera icon under the person's avatar.