Straight edge ideas

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lr27

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Has anyone figured out the centenary curve on a long but taut string? (I haven't.) It could be minimized by using some of that high tech fishing line that's very strong for its size and using a fair amount of tension. If the catenary curve was still significant, it could still be calculated and allowed for. I think, using a very thick foam core or deep truss, you could make a table that stayed flat when moved. I'll admit I haven't calculated how deep such a table would need to be. If you had access to a flat table for a couple of days, you could build yours on top of it, saving a bunch of trouble. I wonder how flat that pond is when it freezes? If it's flat enough, find some glue that sets when cold, and make your table on that.
 

lr27

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You don't live far enough from the equator, unless you can find some ice 9. I've seen ice on a big lake that was three feet thick.
 

Geraldc

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You don't live far enough from the equator, unless you can find some ice 9. I've seen ice on a big lake that was three feet thick.
While we are off topic.My Father used to do curling which is like lawn bowls on ice with big granite stones with handles.He said the difference between natural ice and artificial rinks is that on the natural ice you could control the stone by where you stood.
 

Little Scrapper

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Wait. We're designing airplanes and we can't design a straight, flat table? SMH.
Are comments like this necessary? There’s nothing good about demeaning someone’s question. He’s simply asking for different methods. That’s the whole point of a forum.
 

proppastie

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Well if you do not have a flat table your wing is going to be twisted....if using the same table for LH and RH wings the twist will be twice a much.....It would be very easy for my 22 ft long set of tables to be off 1/2 in or more.....I am not sure my aircraft would be safe to fly with a 1" total twist. If you can rig you wings with drag wires and struts it may not be as critical, but riveted aluminum that is not possible. The factory built aircraft have assembly fixtures that hold the wing very close....even to the point that you can buy another wing or tail and it will bolt right on.
 

Little Scrapper

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That Lowes stud requires order of 180 minimum. No Menards here.
do you have a drywall distributor near you that sells to commercial accounts? They usually are steel stud dealers as well.

Also. Any commercial general contractor has steel studs laying around. They are always friendly and they could either point you in the right direction or even give you a few. Keep trying, you’ll win eventually.

I do think the LP Smart Side trim is wonderfully perfect. But if steel is what you want I’d try the above.
 

BBerson

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Yeah, I had an account at Carl's Building Supply for a while. They are contractor centric. I prefer Home Depot where the DIY guy can pick out a $2 part and see the price, unlike the contractor truckload delivery companies.
My comment was that I have never seen a steel stud in a store with a price on it. Yes there is no doubt somewhere I can get some. But not without hassle. I don't need any now. Thanks for your comments. It's interesting Menards has them.
 

Little Scrapper

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Yeah, I had an account at Carl's Building Supply for a while. They are contractor centric. I prefer Home Depot where the DIY guy can pick out a $2 part and see the price, unlike the contractor truckload delivery companies.
My comment was that I have never seen a steel stud in a store with a price on it. Yes there is no doubt somewhere I can get some. But not without hassle. I don't need any now. Thanks for your comments. It's interesting Menards has them.
It could be geographic. I live in a area that is a sort of bubble with lots of new buildings going up constantly. So our Menards here are quite large and stock everything. I’m not sure what it’s like in other states. Steel studs are very cheap regardless. Most commercial buildings are steel studs here. Cheap, defect free and lightweight. The lumber in these stores are horrendous.
 

davidjgall

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Are comments like this necessary? There’s nothing good about demeaning someone’s question. He’s simply asking for different methods. That’s the whole point of a forum.
There's nothing demeaning about redirecting the thought process into the onboard skill set. An airplane designer can think about tables all night and get absolutely nowhere, but tell him it's a wing and all of a sudden, looky there, he realizes he needs a top cap and a bottom cap and a web, and since it's wide he'll need several webs (like a DC-3), and some cables to tension it on the diagonals and turnbuckles to adjust it's rigging, etc. (or whatever). It was that exact same epiphany that got me a wing table and I thought, correctly, that it might redirect someone else's thinking (witness the immediate next comments from robertl and proppastie).

So, yes, sometimes comments like this are necessary. He's "asking for different methods" and now he has more. "That's the whole point of a forum."

Thanks for the warm welcome. And thanks for all the excellent advice and recommendations you've contributed. Next time I need to build a straight, flat wood table I'll be sourcing the LP SmartSide siding product for my webs. My steel wing table, though, will continue to be my main reference surface, although it will soon be even better, thanks to this forum and the additional research inspired thereby:

 

proppastie

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I am still thinking about attaching 3 engineered boards 6 pieces of plywood together. If I lay plywood on the floor it is going to be hard to get the screws in, so I guess you lay the first board on the floor and support the plywood vertical,....make a simple fixture to make a table.
 

Little Scrapper

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I am still thinking about attaching 3 engineered boards 6 pieces of plywood together. If I lay plywood on the floor it is going to be hard to get the screws in, so I guess you lay the first board on the floor and support the plywood vertical,....make a simple fixture to make a table.
This is why I used a pocket hole jig. It allows me to screw the vertical members in from under the backside.
 

Little Scrapper

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have to get the screw length just right so they do not stick out the top? Or do you break/grind the tips off
I adjust the collet on the drill bit the depth I need. I’m not in the shop but I seem to remember using 1-1/2 screws? I can double check later on.
 
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