Hatch Masters

Anything to do with mechanical, construction etc

Hatch Masters

Postby Guest » Thu Feb 09, 2006 9:08 pm

I made some 1/4" plywood templates for parts of the hatch; one for the 4-internal hatch ribs and one for the 2-external hatch ribs. I also made two other templates, which will be used to build a curved jig to clamp and assemble the hatch in.
I've seen a few pictures somewhere of hatches being glued up and clamped in a curved jig.
I'm at the point to where it's time to trim the master template back 3/4" at the hatch location and after that's done, there will be no more easy referencing these templates to the master template and I've got a question...
Now I know these templates are only 1/4" thick, but I can easily spring them. (Simulating the dreaded hatch springback)
My goal is to have zero, nadda, no springback.
I wondered about taking these templates and putting a little reverse springback (1/4" maybe, because that seems to be about the average I hear builders say they got) and make new tighter templates.
Has anyone tried this or use this method in their builds?
As of right now, I'm ready to proceed and build to the prescribed curve, but thought it would be worth while to ask the question, because we all know there is no such thing as a dumb question, right?
I'm at a point where the switch would be easy... just thought I'd ask.
Build to the prescribed curve or tighten up the templates with 1/4" reverse springback?
Guest
 

Postby madjack » Thu Feb 09, 2006 9:54 pm

Dean...are ya using horizontal or vertical ribs...it is my opinion that vertical ribs have no springback and horizontal ribs have a spring back problem...if you don't follow the H vs V question then horizontal is how the Kuffel Creek plans show to doit and vertical is how we did it...click my WWW button and look at "struts"...our ribs are 3"s at the bottom tapering to 2.5 at the top. The center panel is the only "cross" bracing...when we skinned it we put it in place on the tear, used wedges where necessary to make it sit perfectly and then applied the skin using Gorilla Glue and brads...it worked perfectly...I think Gage did something similar
madjack 8)
Last edited by madjack on Thu Feb 09, 2006 10:19 pm, edited 1 time in total.
A computer lets you make more mistakes faster than any invention in human history - with the possible exceptions of handguns and tequila.
most all personal problems can be solved with the proper application of high explosives
User avatar
madjack
Site Admin
 
Posts: 15108
Images: 177
Joined: Thu Dec 02, 2004 5:27 pm
Location: Central Louisiana

Postby Guest » Thu Feb 09, 2006 10:03 pm

Jack,
My ribs follow the curve, so they would be vertical. (6-total)
I'm not using spars, but I guess you could call them spar spacers or spar blocking... they will be straight and go horizontal.
My end caps will be full width, or almost full width... don't know if those would be considered spars or not.
I went extra tall on my ribs to give them more strength and the outer ones even taller. (Might have to notch the outer ones where my gas struts attach... don't have the struts yet)
Guest
 
Top

Postby Boodro » Thu Feb 09, 2006 10:03 pm

I used 3 vertical ribs on mine, made out of 2 pieces of 1/2 ply glued & braded together. I used 1x2 Poplar stiffners inbetween the ribs . They are 2 1/2 inches wide. I cut them all together on my band saw , then sanded to finish line. mounted the empty frame to the body & laid down 1/8 hardboard, then 1/8 FRP , I had NO springback whatsoever.
Just the way I did it. Pics are in my album. Good luck.
We are all travelers in this world , from the sweet grass to the packin house , birth till death , we travel between the eternities . ( Robert Duvall as Prentiss Ritter)
User avatar
Boodro
1000 Club
1000 Club
 
Posts: 1052
Images: 101
Joined: Sun Oct 10, 2004 9:35 pm
Location: Sylvania, Ohio
Top

Postby Nitetimes » Thu Feb 09, 2006 10:21 pm

I used 5 ribs on mine about 3" - 3 1/2" high, wrapped 2 layers of 1/8" ply over them. I had no springback at all. I wouldn't think with 6 ribs you should have any problem.
I'd say if you tighten them up you may end up with it not closing right if you don't get it to to pull at all.
Rich


Image
ImageImage
-
The strongest reason for the people to retain the right to
keep and bear arms is, as a last resort, to protect themselves
against tyranny in government.
- Thomas Jefferson -
Personally, I carry a gun because I'm too young to die and too old to take a butt kickin'.
User avatar
Nitetimes
7000 Club
7000 Club
 
Posts: 7909
Images: 194
Joined: Sat Feb 12, 2005 12:44 am
Location: Butler,PA
Top

Postby madjack » Thu Feb 09, 2006 10:26 pm

Dean, after reading your second post, I say stay to the profile, don't tighten them up...vertical ribs like you are planning are not prone to springback as horizontal style construction is...we only used 4 ribs onna 4fter and it was plenty...
madjack 8)
A computer lets you make more mistakes faster than any invention in human history - with the possible exceptions of handguns and tequila.
most all personal problems can be solved with the proper application of high explosives
User avatar
madjack
Site Admin
 
Posts: 15108
Images: 177
Joined: Thu Dec 02, 2004 5:27 pm
Location: Central Louisiana
Top

Postby Gage » Fri Feb 10, 2006 1:59 am

Dean,
I did mine about the same way as noted above. I've got 5 ribs for the 5' wide hatch. 1 each on the sides and 3 equally spaced in between. My ribs are 3/4" cabinet grade birch ply and 1 1/2" thick. So don't worry about the springback. Just worry about finishing it by May. :lol:

Have a good day.

8)
Image Image Image
Remember 'Teardrop Time'.......Take your time, you don't have to have it finished NOW.
User avatar
Gage
8000 Club
8000 Club
 
Posts: 8321
Images: 28
Joined: Sat Apr 17, 2004 9:14 pm
Location: Palmdale, CA
Top

Postby Guest » Fri Feb 10, 2006 2:21 am

Thanks Guys,
Building in a little tighter radius would be a guessing game at best, I'm relieved to hear that those building with vertical ribs get no springback.
The woodworking part is pretty fun... I'm doing things with a router that I've never done before, making that tool pay for itself.

Gage,
I'd have this thing at least towable by May easy, if I could work on it all the time.
It is going to be a challenge just to have something to show for by July, I think... But I'm going to just keep plugging away at it. I really doubt that I'll have something towable by the Dam Gathering, but I will be there regardless. Commercial work is starting to get busy... I'm sure someone is going to squak come the end of July when I disappear into the redwoods for a week.
As far as building the hatch, I'm going to assemble the framework, mount it on the trailer to check for allignment, mount the latching hardware, run the wiring, remove it and skin it in the jig.

I've got to laminate some hardwood strips on the hatch and on the body where the door seal goes and if the strips on the hatch exert too much pressure, I'll just steam bend them first them laminate them.
Guest
 
Top

Postby Gage » Fri Feb 10, 2006 3:37 am

Say dean, check out page 12 of my build. That might help a little. It's at:
http://www.gages-56.com/tear12.html

First time to a Gathering.
Image
One year later to it's second Gathering. This was the Gathering that I lost the trailer going to it.
Image

Have a good day.
8)
Image Image Image
Remember 'Teardrop Time'.......Take your time, you don't have to have it finished NOW.
User avatar
Gage
8000 Club
8000 Club
 
Posts: 8321
Images: 28
Joined: Sat Apr 17, 2004 9:14 pm
Location: Palmdale, CA
Top

Postby Guest » Fri Feb 10, 2006 4:16 am

Thanks Gage,
I'll bring what I have to Pamplin, but I doubt I'll be anywhere ready to tow something to the Dam...
Doug has offered to come up some weekend and help me out, but that's contingent on him finishing #2 and whether or not my shop is plugged up with storefront metal...
I'm just happy to be able to be making progress, even if it's a little here and a little there. :thumbsup:
I just know that April and May are going to be busy months as far as commercial work goes...
Hey, I'll be doing all the storefront, entryways, glass and mirror work at the new complex that Almquist Lumber is building... maybe I'll get some good deals on teardrop materials???
I'll be working a limited schedule during Presidents week, because I have my kids... I'll get to work on the teardrop with my little helpers. :twisted:
Guest
 
Top

Postby Gage » Fri Feb 10, 2006 4:24 am

Dean in Eureka, CA wrote:I'll be working a limited schedule during Presidents week, because I have my kids... I'll get to work on the teardrop with my little helpers. :twisted:
Well at least you won't have to worry about directions. I'm sure the TDN will keep you going in the right direction. :lol:

Good night.

8)
Image Image Image
Remember 'Teardrop Time'.......Take your time, you don't have to have it finished NOW.
User avatar
Gage
8000 Club
8000 Club
 
Posts: 8321
Images: 28
Joined: Sat Apr 17, 2004 9:14 pm
Location: Palmdale, CA
Top

Postby JohnF » Fri Feb 10, 2006 1:40 pm

I built my Cubby's hatch with horizontal spars and thought I had it perfectly fitted to the frame...but I now have spring back.

What to do? Throw it out and start over? I really don't want to do that. I put a ratchet strap around the bottom and looped it throught both open doors and pulled in in...seems to fit, but I am uncertain how to proceed. I could come up with some way to cinch in the bottom with 'over the top' hasps or some thing like that.

Since spring back seems so darn common there must be some generally agreed-to method of getting out of a bad situation.

What do you recommend?
JohnF
Donating Member
 
Posts: 88
Images: 5
Joined: Wed Sep 21, 2005 7:31 pm
Location: Salida,Colorado
Top

Postby alaska teardrop » Fri Feb 10, 2006 2:35 pm

Two thoughts - John, if you have the clearance, How about two stainless cables with turnbuckles from top to bottom of the hatch? (Call them clothes lines :lol: ) As for vertical ribs - sandwich matching 1/16 aluminum between the plywood ribs?
Northern Lite Traveler design: viewtopic.php?f=27&t=51991
User avatar
alaska teardrop
Platinum Donating Member
 
Posts: 1058
Images: 172
Joined: Wed Aug 24, 2005 1:41 pm
Location: Greenville, Michigan
Top

Postby JIML1943 » Fri Feb 10, 2006 5:53 pm

HEY GUYS
I've got springback also and i've got 5 vertical ribs.It's only 3/4"at very bottom and not realy hard tp push in
I bought two popup trailer latches should be hear any day now i thank they will work will let you know how they work & look.


happy camping Jim :)
Some days all you can do is smile and wait for some kind soul to come along and pull your ass out the bind you've gotten yourself into.

Image
Happy camping Jim & Barbara
User avatar
JIML1943
Teardrop Master
 
Posts: 230
Images: 71
Joined: Tue Sep 28, 2004 7:22 am
Location: Lexington,N.C.At highrock lake
Top

Postby JohnF » Fri Feb 10, 2006 7:05 pm

I have been thinking it over...new hatch vs. buying two 'over-center' side pull latches from Austin Hardward for around $50....I can pull in the bottom with a ratchet strap, so the over-center units should also...I think this is what I am going to do...Austin Hardward part nr 341 give 2.5-inches of adjustment, and I have far less to pull in.

Like the old lady on the old Saturday Night Live program would say,
"If its not one thing, its another!"

Thanks for the help, gentlemen.
JohnF
Donating Member
 
Posts: 88
Images: 5
Joined: Wed Sep 21, 2005 7:31 pm
Location: Salida,Colorado
Top

Next

Return to Teardrop Construction Tips & Techniques

Who is online

Users browsing this forum: No registered users and 2 guests