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Old 5th February 2013, 04:10 PM   #561
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Yes.
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Old 5th February 2013, 04:27 PM   #562
xrk971 is online now xrk971  United States
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Playing around with CAD model of 24 in "True" Cornu function spiral horn. It would look cool in all wood.
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Old 5th February 2013, 04:39 PM   #563
ryani is offline ryani  United States
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Thanks for the knife tip. I do have one sheetrock knife you can extend the blade out increments so that should prevent cutting all the way through.

Yes i figured for 4 bucks a sheet i can experiment with the design and if it turns out good then I can build a set of the full scale ones. I'll have to buy 2 full 4' by 8' sheets for that project.

I saw the cornu version with gentleman the used monacor sp-50x drivers. WOW is all I can say.

I used a set of those just in a set of micro towers for my budget basement system and I'm very impressed with them. I can imagine they sound quite will in the cornu horn

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Old 5th February 2013, 06:47 PM   #564
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There are breakoff razors- good for keeping it sharp, just snap off the section and advance another one.
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Old 6th February 2013, 12:59 PM   #565
ryani is offline ryani  United States
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Last night after cutting two sheets with a sheetrock knife I had an epiphany. Why not use one of my sheet metal snips from work. Works like a charm! Way faster and cut a straight line without swerving.
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Old 6th February 2013, 04:16 PM   #566
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Your epiphany is not for every man it seems. I tried it with a number of tools.

Table saw - really fast but jagged edges
Hand saw - slower but still fast, slightly less jagged edges
Tin snips - slow, crushed the edge
Chef's knife - a little faster but hard to control
Serrated bread type knife - what was I thinking? The noise it made was as bad as nails on a chalkboard
Straight blade (drywall) - good but couldn't do the scoring
Hook blade (roofing) - another dumb idea
Olfa knife (box cutter) - the only practical means I tried

I thought I had the cat by the tail by bundling and cutting it on the table saw. Took less than 2 minutes to cut all the pieces for the 80 cm horn but the blade was chunking out the foam because it got hot enough to melt the polystyrene and pieces ended up stuck to the carbide tips. It was a ***** to clean until I took a piece of wood and ran it through. Cleaned it up right nice.
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Old 6th February 2013, 07:18 PM   #567
xrk971 is online now xrk971  United States
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This is my favorite blade that I use for all builds in foam core. You can sharpen it on ceramic stone to extend life by quite a bit.
#11 Classic Fine Point Knife Blades | X-ACTO

I use the basic #1 precision knife.
The Original #1 Precision Knife | X-ACTO

Gives very clean edges and straight or curved cuts.

You can see the quality of the cuts this knife makes here:
Click the image to open in full size.

Last edited by xrk971; 6th February 2013 at 07:20 PM.
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Old 6th February 2013, 08:02 PM   #568
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Quote:
Originally Posted by xrk971 View Post
This is my favorite blade that I use for all builds in foam core...
I use the basic #1 precision knife.
The same scalpel use for dustcapectomies.

dave
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Old 6th February 2013, 09:10 PM   #569
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The same ones (top two in the link) that we used for actual 'cut and paste' when doing newspaper production. There were no Olfa knifes back then. I still have my handle and some odd blades from about 35 years ago.
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Old 6th February 2013, 10:29 PM   #570
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So I put the LG drivers back in. The JVC's are a bit lacking in the lows. Nice highs mind you but only as good as the LG's
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