V - Witt / Witts V

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Little Scrapper

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I never posted my steaming process for these ribs so here are 3 photos from today.

Pretty standard stuff. Steam for 30 minutes on a hot plate and clamp it up until tomorrow. Steam tube is just propped up on a wall mounted pencil sharpener. Seems to work pretty well overall. Even at 30 minutes the wood is actually quite stiff and there’s lots of pressure to hold it. 1/2 x 1/4 is much suffer than 1/4 x 1/4 when trying to bend.

613C1C2E-861B-4541-806C-6690C95B6923.jpeg

Top view of jig.

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Kind of a side view showing the brass strip used as a platten so the wood cam locks don’t put divots in the freshly steamed Sitka Spruce.

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Little Scrapper

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How did you define the curve for jig? And thanks to Jim for the answer about the thickness of the wing skin.
Well, same as many of the older airplane plans. There’s a template that comes in the plans. The plans also gives a length and a spar center so between all that I just made a copy from a local blueprint copy place and cut it out with a scissors. Drew around it, made some adjustments with the spar centers and just went with it.

it’s close enough. I put the freshly glued rib on the original template sent with the plans and it’s very very close.

Some plans come with airfoil measurements, these do not which is pretty cool. Very “Steve Wittman” ish. I’m not a engineer type in my personality so I actually prefer the Wittman way of doing things.
 
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I mean jig for bending steamed rod. When you take out the steamed slats from the jig, they are unbent.
And I bought the plans V-Witt, I waited three months by mail!
 

Little Scrapper

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I mean jig for bending steamed rod. When you take out the steamed slats from the jig, they are unbent.
And I bought the plans V-Witt, I waited three months by mail!

Gotcha. the steam jig is the exact curve of my airfoil top and bottom. I could have “over curved” it but decided not to. So when I pull it out of the steam tube and start camping it in the steam jig it’s a bit stiff but it works perfectly!

If you look at the photos I put marks on the steam jig and the rib jig so the cap strip aligns perfectly. It seems to work well.

I was unclear of what you meant earlier in your post. Any questions you have of what I’m doing just let me know.

Mike
 

Little Scrapper

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If anyone reading this thread is interested I bought a shop scissors at Harbor Freight for .94 Lol. Less than a dollar!!!! I figured it was worth trying to put it through it’s paces. It’s actually a great scissors. It cuts 1/16” mahogany plywood quite well. I’m using it for cutting the post cards and it’s excellent for that.

Anyhow, it’s .94 so give it a shot next time you’re near the store.

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Little Scrapper

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Below is how I optimized my 2’ x 4’ plywood sheets. I like the smaller sheets, just easier to deal with and it’s cheap to shop and no penalty for being small.

I took typing paper and taped them together and took the aluminum gusset patterns and just played around with them until it made sense. I’m not a computer guy so the whole “nesting” thing is beyond me. It didn’t take long and was pretty fun.

I came up with a winner and measured it. Each rib needs a 19 1/2” X 7 3/8” piece to get the gussets out of. This piece of paper will hang in my shop as a reference so I can cut up the 2 x 4 sheets.

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Here is a half azzed drawing of a 2 x 4 sheet and what the 19 1/2” x 7 3/8” looks like inside it. Basically I can fit 6 with the grain and the left over will get me 1 more for a total of 7. So I can get 7 ribs done with a 2 x 4 sheet.

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VP1

Todd C.
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Looking good Mike. With those high quality jigs and gusset patterns you’re just about ready to go into production making kits! :)

Hey, have you tried 2oz condiment cups for mixing epoxy? They’re cheap as dirt on amazon and I find them a little easier to use when weighing epoxy.
 

Little Scrapper

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Looking good Mike. With those high quality jigs and gusset patterns you’re just about ready to go into production making kits! :)

Hey, have you tried 2oz condiment cups for mixing epoxy? They’re cheap as dirt on amazon and I find them a little easier to use when weighing epoxy.
I have not. I’ve done volume measuring and I just don’t care for it because of the time it takes to scrape it out and the fixed sizes.

with weighing I can mix any amount I’d like in a matter of seconds. There’s zero waste and it’s just so mess free that I prefer it.

Keep in mind though I only do it for small batches. If I were to mix for large glue ups I’d use volume method.

Here is how I have it worked out.

The first side of a rib takes exactly 15.37 grams of epoxy. If I mix this to weight which takes a few seconds I have zero waste. Right now I have 6 ribs made of 22 and each one comes out exact. When I flip it over after the first side cures I consume 16.97 grams. The second side is more because I coat the Sitka spruce members under the gussets so later when varnishing I won’t need to get inside. So that’s what works for me. In order to have zero waste with volume mixing I’d need to find the exact size of the container.
 
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Little Scrapper

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I shoulda been more clear. I too weigh my T-88 out, I just use the little cup to keep everything contained and portable.
Gotcha. Yeah, that’s how I originally tried it. For me it was too messy and time consuming. I experimented with different ways and now I just squirt it in to a piece of index card material and hold it vertically while I scrape it off on to a mixing paper with one scrape using a another piece of index card. It just worked out perfect for me that way. Extremely fast and zero waste.

I’m probably the only one that does it that way, haha, but I just love it.
 
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