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  #1  
Old 05-20-2017, 11:40 AM
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rvanstory rvanstory is offline
 
Join Date: Dec 2016
Location: New Braunfels
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Default Trim Tab Bending Solution

Well, they say 3rd time's a charm!!! For all you "average" builders (like me) that struggled with the trim tab bends, I FINALLY found a solution that worked very well for me. Thought I'd share it in case you are approaching that step in the plans (9-16).

My struggle was with the suggested Van's "wedge". Both times the wedge would slip (bottom 1st try, and top 2nd try) that damaged the skins. In spite of my best efforts with 2-sided tape. The third try NOT using the wedges worked!

Here's the method that worked for me (on 3rd try!!!):
Step 1. Take a flat piece of steel and round the edges (to not crease the bend) and taper one end to fit up into the trailing edge bend.




Step 2. Clamp the skin between the steel bar and edge of work bench. Let the edge of skin and bar overhang the edge of workbench slightly. It helps when tapping the bend with a rubber headed hammer. Once clamped, tap (slowly) the edge over with a rubber headed mallet. For the small tapered end, finish it's bend by slowly tapping with a upholstery nail hammer. Using the steel bar instead of the wedge allows you to slightly "over bend" the tab to allow for the spring-back effect.





I also found bending the OUTER tab first worked best. By bending the outer tab first, the two skins came together nice and flush against each other. Hope this helps someone else avoid the frustrations I've had with this simple little part of the build!!

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  #2  
Old 05-20-2017, 11:56 AM
RV7ForMe RV7ForMe is offline
 
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Default Looks great!

Looks like this method really worked out great for you. Looks perfect to me!
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  #3  
Old 05-20-2017, 12:48 PM
RandyAB RandyAB is offline
 
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Location: St Albert, Alberta, Canada
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Thanks for this idea. I'm very close to this point in the build and will probably use this method.

Having bent the elevator tabs, I'm really wondering what the big deal is about this. They are both 16 thousandths thick. Bending the elevator was easily done with a piece of softwood to start and then finished with a hand seamer. They turned out perfectly.
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  #4  
Old 05-20-2017, 02:13 PM
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rvanstory rvanstory is offline
 
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Quote:
Having bent the elevator tabs, I'm really wondering what the big deal is about this.
I hear you! I thought the same thing. The difference in these and the elevator tabs is that these skins are one (not separate top and bottom). With the elevators you were able to use a "flat block" clamped down to hold the tabs while bending.

In my opinion, it's the Van's method they describe in the instructions (using two wedges) that makes it more difficult. At least that's what created my issues. It was the slope of the wedges that kept the clamp from holding as well and they slipped on me. Each time damaging my skin.

The method I described in my post does away with the sloped wedge and allows a more solid clamp that won't slip, just like the elevator skins.

Hopefully you can become a member of the ONE TAB CLUB by making it easier on yourself the 1st time.
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  #5  
Old 05-20-2017, 03:48 PM
RandyAB RandyAB is offline
 
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Location: St Albert, Alberta, Canada
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Quote:
Originally Posted by rvanstory View Post
I hear you! I thought the same thing. The difference in these and the elevator tabs is that these skins are one (not separate top and bottom). With the elevators you were able to use a "flat block" clamped down to hold the tabs while bending.

In my opinion, it's the Van's method they describe in the instructions (using two wedges) that makes it more difficult. At least that's what created my issues. It was the slope of the wedges that kept the clamp from holding as well and they slipped on me. Each time damaging my skin.

The method I described in my post does away with the sloped wedge and allows a more solid clamp that won't slip, just like the elevator skins.

Hopefully you can become a member of the ONE TAB CLUB by making it easier on yourself the 1st time.
I just did this step a couple days ago. Lol.....confession time. I almost made a big boo boo. I clamped the skin to the edge of the table and bent it before realizing that I had both the top and bottom skins perfectly together and that I did both skins at the same time!! They both were perfect! Luckily it was the first skin(s) that I did so all I had to do was swap the bottom skins. What was originally supposed to be the bottom R became the bottom L.

Needless to say, it was a little less stiff rolling the other two skins one at a time.
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Last edited by RandyAB : 05-20-2017 at 03:51 PM.
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  #6  
Old 05-24-2017, 02:50 PM
RandyAB RandyAB is offline
 
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Location: St Albert, Alberta, Canada
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Hey Randy.

I used your method today to finish up the L trim tab which I pressed last night. It turned out perfectly. After clamping I used a small block to gently hammer them into place. It really was a total non-event. Thanks for posting this!

Now I on to the R trim tab.

All the best!
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  #7  
Old 05-25-2017, 12:00 AM
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N804RV N804RV is offline
 
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Location: Mount Vernon, Wa
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Took me 4 tries. I had set the trim tab aside and moved on to other stuff because I was so frustrated with it. Well, today I went tried this technique. And, It worked great! Thanks!

I used a heavy steel back-riveting plate on top before finishing the trailing edge bend. I also attached an aluminum straight edge on the face/edge of the table top. Nice tight neat bends. Very easy to do!
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Last edited by N804RV : 05-25-2017 at 12:03 AM.
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  #8  
Old 05-25-2017, 04:04 PM
sritchie sritchie is offline
 
Join Date: Jun 2015
Location: Boulder, CO
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I was only able to get the vans method to work by adding double-sided tape to each block before making my bends. Any way other than this and they slipped like mad and ruined my bend. Glad you found a better way!
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  #9  
Old 08-18-2019, 05:41 PM
tomjj tomjj is offline
 
Join Date: May 2018
Location: Brighton, CO
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Quote:
Originally Posted by sritchie View Post
I was only able to get the vans method to work by adding double-sided tape to each block before making my bends. Any way other than this and they slipped like mad and ruined my bend. Glad you found a better way!
Agreed... the method described in the plans will only work if you run double-sided tape along the entire length, on all contact sides of each block before making the bends. On my second attempt (must be an RV rite of passage ) I personally used 3/4" Intertape 591, (https://www.amazon.com/gp/product/B0178G341A) and had zero problems doing it the plans way with this tape; it sticks like crazy (but is reasonably easy to remove) and is the exact width of the blocks.

Last edited by tomjj : 08-18-2019 at 05:44 PM.
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