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I'm going to be adding a pair of helicies to my latest layout revision, and I'm trying to decide if I should go with a premade kit (like the one Ashlin Trains supplies) or if I should build my own.
14" radius with a 6" or 8" gain in elevation for one helix (depends on what the final measurements are once I'm done my planning... I'm thinking it will be an 8" change in elevation though)
And if this plan works the way I want it too (which I'm seriously reconsidering this part because of the complexity it will require) is a 20" helix with an off ramp @ "8 inches.
No need for the helix to be double tracked (in fact, I think I'd perfer if it wasn't!)
How hard is it to create one yourself?
I assume it would be as simple as buying a sheet of 4x8 thin plywood, then cutting it up into the strips you need then using four beams @ each 1/4 level attach the strips to each beam for the desired height... much like a 4x8 plywood cookie-cutter layout?
Because if thats the case, it should be fairly easy!
Especially if it's a 2" seperation between levels. The hardest part would be cutting it up no?
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A 14" radius, gives you a circle circumference of 87.9", so each complete "loop" of you helix will take 88" of track. To rise 6", with 2" clearance will take three circles, minimum.
If you use quarter circle pieces (to get the most out of a sheet of plywood), you have to allow for the reinforcing cleat at each joint. This affects clearance, and, therefore, the grade of each circle of the helix. I would consider 3/8",or1/2" plywood, with edge doweling of each section joint.
Quote:And if this plan works the way I want it too (which I'm seriously reconsidering this part because of the complexity it will require) is a 20" helix with an off ramp @ "8 inches.
The only caveat here, is that your turnout for the off ramp be placed far enough back to allow the "ramp" to follow the helix, at a decreasing grade around the outside, to insure there's no sudden change of grade. Just as curves work better with easements, so do grade changes, and this will be happening under the layout where derailments, or other problems, will be particularly frustrating.
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thanks a bunch!
I'm thinkin I'll use 3/8 plywood for my helix. And I'll be doing it from scratch.
Square 1/2 dowel is what I'm thinking for the cleats.
My only issue is I have to find a place to chop the wood up! (let alone get it home)
foams easy, it comes in 2'x8' slabs, and I can get that in my car... but a 4x8 sheet of plywood is a whole 'nother story!
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Hope I'm not too late. Most places where you can buy plywood, offer cutting services. A 4' X 8' sheet can be cut to 4' X 4', or smaller. there might be a fee for the cutting, ask.
We always learn far more from our own mistakes, than we will ever learn from another's advice.
The greatest place to live life, is on the sharp leading edge of a learning curve.
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not too late at all.
The issue is my trunk can't handle anything bigger than 2' across. sucks I know, it made buying the pink foam a lot more expensive than it should have been!
And the local hardwood places seem to only be setup for cutting it length wise not width wise...
however, there is hope! I have a construction friend who is willing to supply with parts if he can help build. It was a childhood thing of his too, but he was too embarassed to tell the wife until they came over for dinner last week and fell back in love with the trains!
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Quote:however, there is hope! I have a construction friend who is willing to supply with parts if he can help build. It was a childhood thing of his too, but he was too embarassed to tell the wife until they came over for dinner last week and fell back in love with the trains!
When need arises, a way can be found. Sometimes in places not thought of.
We always learn far more from our own mistakes, than we will ever learn from another's advice.
The greatest place to live life, is on the sharp leading edge of a learning curve.
Lead me not into temptation.....I can find it myself!
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Hi guys, I'm thinking to "glue up" the circle pieces you could use a spline joint, or a biscuit or maybe a half lap joint.
A half lap would have lots of surface for the glue without adding to the thickness of your plywood.
Joe
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I recall seeing a helix made with 1"x4" clear pine - the curve was segmented, with the ends of each segment angled to whatever degree required to allow for the desired radius. Biscuit or lap joints should work for this type, too, and you'd have no trouble fitting lengths of board into your car.
Wayne
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I have no idea what you guys are talking about when it comes to a biscuit or lap joint.
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Wiredup Wrote:I have no idea what you guys are talking about when it comes to a biscuit or lap joint. ![35 35](https://bigbluetrains.com/images/smilies/extra/35.gif)
A biscuit comes with the KFC "Extra Crispy" meal. Lap joint is the bar with exotic dancers....
OK....I have no idea either.
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Biscuit joint: a biscuit is a pointy circle of wood. A fancy saw cuts a slot (arc-shaped) into both joining surfaces and the biscuit is slathered with glue and everything assembled.
A lap joint is one where another piece of wood is placed over the joint and this is glued to both pieces -- looks like a set of brick joints. Extreme lapping would involve having 2 sets of parts and assembling a double layer offset by 1/2 a piece, again like 2 courses of bricks.
I'm not sure about a half lap -- some of the board is removed and two thin pieces are joined?
David
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<!-- m --><a class="postlink" href="http://en.wikipedia.org/wiki/Butt_joint#Biscuit_Reinforced_Butt_Joint">http://en.wikipedia.org/wiki/Butt_joint ... Butt_Joint</a><!-- m -->
<!-- m --><a class="postlink" href="http://en.wikipedia.org/wiki/Lap_joint#Half_lap">http://en.wikipedia.org/wiki/Lap_joint#Half_lap</a><!-- m --> - the end lap or splice is what you'd be most likely to use.
Andrew
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