Layout drawing of horn curves for DRs

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Harley
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Layout drawing of horn curves for DRs

#1 Post by Harley »

Image

Image

These sketches are NOT to scale...ok! They are an indicative illustration.

Mods - perhaps this should be a sticky?
ImageSemi-retired: Former Australia and New Zealand Authorised BFM cab builder.

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Bill Fitzmaurice
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Re: Layout drawing of horn curves for DRs

#2 Post by Bill Fitzmaurice »

Harley wrote: Mods - perhaps this should be a sticky?
This proceedure has been shown in the plans, page 7, for nigh on a year now.

Mud B. Wetdirt
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#3 Post by Mud B. Wetdirt »

Harley, Thankyou sir I now remeber the post and what to do.
Bill, I have the upper on page 7 but not the lower.
Next I will put it on a floppy.

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fender3x
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#4 Post by fender3x »

The great thing about this approach is that it works any time you need to draw or cut a curve. From the end points draw a curve at the specified radius. Where the two curves cross is the center point for drawing/cutting your curve. Just look at the end points and radiuses in Harley's charts, and forget about the rest of the drawing and you will see what I mean.

I just used the approach yesterday to cut the curved side of my DR's access port. Worked like a charm.

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Harley
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Re: Layout drawing of horn curves for DRs

#5 Post by Harley »

Bill Fitzmaurice wrote:This proceedure has been shown in the plans, page 7, for nigh on a year now.
Rrriigght! :oops:

Shows you how often I read them through! I like skipping right to the end straight away as I'm impatient to find out what happens! :lol:

Harley
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DJPhatman
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#6 Post by DJPhatman »

Anyone in the USA know of any sources for a large compass? I tried the piece of wood trick, but it didn't come out right. :oops:

I can use tools, just can't MAKE them!!
I know money often seals the deal, but seriously, quality is an investment, not an expense... Grant Bunter
Accept the fact that airtight and well-braced are more important than pretty on the inside. Bill Fitzmaurice

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Harley
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#7 Post by Harley »

DJPhatman wrote:Anyone in the USA know of any sources for a large compass? !
I would be interested to know that also. There are many uses for one in my factory.

Here's some interesting devices that would do the trick - available in Pomgolia - but must be obtainable in the US

http://www.axminster.co.uk/product-Veri ... -22799.htm

edit - http://art-supplies.misterart.com/store ... o-4211.htm there is a 36" beam compass there for just on $US12

Harley
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fender3x
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#8 Post by fender3x »

DJPhatman wrote:Anyone in the USA know of any sources for a large compass? I tried the piece of wood trick, but it didn't come out right. :oops:

I can use tools, just can't MAKE them!!
I have the a similar problem with making tools. However, I have found a really easy way to do the compass. My local Ace Hardware gives away wooden yardsticks that advertise the store. I have also seen these on sale at other hardware outlets for a buck or two. They are about 1/8" thick.

What I did was drill a hole just large enough to pass the head of a finishing nail right at the top of the hash mark for 1". I drilled another for hole just large enough for a pencil point to stick through at the appropriate hash mark (radius+1") that I want. So for a 25" radius, I drilled over the 26" hash mark. Drive a finishing nail into the centerpoint for your radius, drop the stick over the finishing nail, and draw your radius.

So far every radius that I have cut/drawn this way has worked beautifully (horn mouth, but cheeks, access ports, brace marks). If it works this well for me, the king of confusion, it can work for anyone ;-)

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LelandCrooks
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#9 Post by LelandCrooks »

This is what I use.


Image

Mark N Mount® (formerly the Mark-It®)



Construction: Two 24" extruded aluminum rails joined at the ends with plastic end caps.
Three sliding guides can be moved along the length of the tool to mark accurate mounting points. One end cap contains a level vial, and the other contains a plumb vial.

Applications: Measure, level and mark with one tool. Hang pictures, mirrors, lights, clocks, shelves, towel bars and more like a pro.
If it's too loud, you're even older than me! Like me.
http://www.speakerhardware.com

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Harley
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#10 Post by Harley »

LelandCrooks wrote:Image
.
Thanks Leland.

What do you use for the larger radii of 25". 26" and 28"

Harley
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LelandCrooks
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#11 Post by LelandCrooks »

The sliding scale goes to 25". There are three holes in the end of the caps that allow you to go almost to 30". They are marked for the amount of distance they add to the scale markings. It does require a little practice not to move the sliders in an arc. Quick and dirty for straight lines.
If it's too loud, you're even older than me! Like me.
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fender3x
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#12 Post by fender3x »

I have to admit that Leland's tool is cool and that I want one...

Still... there are some advantages to my ultra-cheap method (asside from the fact that it goes with my lifestyle...)

For example. It costs no more to have two of my yardstick-with-two-holes-in-it tool than to have just one...seeing as I got them free.

If I use two yardsticks with holes in the same places, two finishing nails and one headed nail, I don't even have to draw the curve. I mark the end points with finishing nails


I put the headed nail upside down through the pivot point in the two sticks so that they make a V shape.

http://image2.frappr.com/pix2/i/2007060 ... _large.jpg

http://image2.frappr.com/pix2/i/2007060 ... _large.jpg

http://image2.frappr.com/pix2/i/2007060 ... _large.jpg

I replace the flat head nail with the point of my trammel arm, pull the finish nails and cut.

http://image1.frappr.com/pix1/i/2007060 ... _large.jpg

Low tech cheap.

(edited june 5)
Last edited by fender3x on Tue Jun 05, 2007 2:21 pm, edited 3 times in total.

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DJPhatman
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#13 Post by DJPhatman »

Harley wrote:edit - http://art-supplies.misterart.com/store ... o-4211.htm there is a 36" beam compass there for just on $US12

Harley
You have to purchase the 13" beam also, as the 36" beam is an add-on. But still a worth while investment. :D
I know money often seals the deal, but seriously, quality is an investment, not an expense... Grant Bunter
Accept the fact that airtight and well-braced are more important than pretty on the inside. Bill Fitzmaurice

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Harley
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#14 Post by Harley »

DJPhatman wrote:You have to purchase the 13" beam also, as the 36" beam is an add-on. But still a worth while investment. :D
Yeah, I saw that after I posted! :oops: :lol:

Harley
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Mud B. Wetdirt
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#15 Post by Mud B. Wetdirt »

What about a yard stick compass about 9 bucks you can get them online or I think it's Woodcraft
http://www.misterart.com/store/view/001 ... ompass.htm

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