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Foam Wing Cutter

What rating Power Supply should I use

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alex nicol14/11/2019 11:57:31
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305 forum posts
15 photos

I'm hopeing somebody can give me a steer on a suitable foam wing cutter set up.

I have a variable 9 - 24vdc/3a/72w PSU and was wondering if this would be adequate and what cutting wire would be recommended

Cut length will be in the 0.75m to 1m range.

Thanks

Alex

kevin b14/11/2019 17:56:23
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1674 forum posts
134 photos

There seems to be a fair bit of information on YouTube, but little on the forum and all the links are out of date.

I too would be interested in any advice.

Alan Hilton14/11/2019 18:15:18
109 forum posts

The most up to date power supply is to use a 3 or 4 cell lipo and an esc with a nichrome wire bow .I have no experience with this setup but if you go onto the RCMF forum a member PDR is expert on this .I use a 240 to 25 volt transformer and a big series wound variable resistor in series.This works well but I scrounged the hardware ,I think the cost of ‘this ser upwould be far too high if bought new

Alan

sticky fingers14/11/2019 22:39:33
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117 forum posts
14 photos

Your power supply could be a 12 volt battery , an electric fire element straightened and a simple bow assembly , experimentation is the key as the length of wire and power input all dependent on wing span. Wing panels can be made in sections and joined.

Chris Freeman 315/11/2019 05:14:31
282 forum posts
371 photos

My set up uses a transformer with a light dimmer switch so you can adjust the power needed for the foam that is being cut and the length. The denser the foam and the longer the foam requires more heat. If you cut with a wire that is too hot you get a ripple effect and the wire can stretch so you loose accuracy, too cold means a slow cut. My transfomer also has an amp meter so you can see where you are when switching on heat wisect 2.jpg. The bow design is also important as you need to tension the cutting wire. This is how mine looks. I was given this set up and am not the best to describe electronics.

Phil B15/11/2019 08:11:29
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168 forum posts
161 photos

You need nichrome wire which is high resistance good for heat elements. The longer the wire the more volts you need to give the current needed to get the temp right. Wire available in cheap coils search or go to flea Bay.

Phil B15/11/2019 08:13:34
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168 forum posts
161 photos

I know a guy who uses metal guitar strings about 3 foot long, probably the top E string! He gets the right tension by tuning it! He can play status quo songs while it's warming up! 😜

Rob Ashley15/11/2019 09:04:54
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246 forum posts
84 photos
Posted by Phil B on 15/11/2019 08:13:34:

I know a guy who uses metal guitar strings about 3 foot long, probably the top E string! He gets the right tension by tuning it! He can play status quo songs while it's warming up! 😜

laugh - Phil that made me laugh for ages.....

David Hall 915/11/2019 10:50:28
166 forum posts
5 photos

The next time that I try foam core cutting, I'll try this wire...

here

Ken Lighten15/11/2019 13:02:06
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249 forum posts
42 photos

Available here Wire

Torsten Spitzner15/11/2019 16:15:02
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28 forum posts
17 photos
Posted by Phil B on 15/11/2019 08:13:34:

I know a guy who uses metal guitar strings about 3 foot long, probably the top E string! He gets the right tension by tuning it! He can play status quo songs while it's warming up! 😜

I have used guitar strings successfully. The thinnest one there is. Simply connected to a 12V battery. Worked well enough over 700mm span.

Mark Kettle 118/11/2019 22:24:40
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2471 forum posts
1492 photos

Hi Alex,

I use nichrome wire see link. ( 80//20 nickel-chrome alloy resistance wire )  Web site for hot wire

I too have used the above wire from broken electric heaters, however it can be ordered on a 60m length bobbin, your power supply is adequate, however I tend to use a 12V DC battery charger with a 12v car battery in parallel.

The wire has a outer diameter of - 0.71mm - which is like a guitar ( note g-string ) which I've also used many years ago.

20191118_205425.jpg

I've got bows from 15" to 50 " in length.

Here's a auto- slicing cut going on :-

20141004_224200.jpg

 

 

 

Edited By Mark Kettle 1 on 18/11/2019 22:30:32

alex nicol23/11/2019 15:18:44
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305 forum posts
15 photos

Quick Update,

I bought a 24v 3a laptop type power supply with an adjustable output of 9 to 24v (about £8 on ebay)

The current bow is circa 33"with 0.5mm nichrome wire giving a resistance value of 7.8 ohms and giving a nice cut at about 15v. Next step is to extend the bow to around 44" and try again.

One question I do have, is what material do you find works best for cutting template

Thanks

Alex

FlyinFlynn23/11/2019 19:46:50
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67 forum posts
64 photos

glass fibre sheet... or SRBP if you can find some uncoated

bert baker23/11/2019 19:53:42
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1482 forum posts
305 photos

I’ve been told the iron on kitchen worktop edging is good,,,

But I rather fancy the newer stuff is probably not as hardy as it used to be

Martin McIntosh23/11/2019 20:14:01
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2970 forum posts
1090 photos

My simple bow is a length of polypipe with wooden arms at each end extending up and down from the wire which is tensioned with a couple of lengths of strimmer line and a turniquet ( how do you spell that?) of piano wire in the centre which is held in position by the pipe once wound up to tension. The cutting wire came from Nexus. Power is from a huge 24V transformer which I sort of obtained and the temperature of the wire is set by winding the ends round the wooden arms until just right. Sounds more complex than it actually is.

leccyflyer24/11/2019 08:31:20
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1290 forum posts
302 photos

It's spelled windlass.

Some years ago we made a few very simple, effective foam cutting bows with three pieces of 2x1" PAR, with tension applied by a windlass on a stout nylon cord across the two arms at the top. Make up a set of asymettrical "rugby posts" with a notch cut in the upper section on each side, fix the cord across between this, then use a stout stick through the cord, winding this up to tension the cord.

Power supply varied between a couple of car batteries, a Minicraft minidrill power supply and an MCA foam cutter power supply. Something between 12v and 24v worked well, depending on the length of bow, which varied from 12" -42".

Bert24/11/2019 10:48:20
514 forum posts
10 photos

Don’t buy wire from amazon or RS, far too expensive.

Get it fromThe Crazy Wire Company

Bert

alex nicol26/11/2019 23:52:50
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305 forum posts
15 photos

Just made and quickly tested a 48" bow, it cut nicely about the 20v mark, the set up is a bit crude but so far so good.

Unfortunately lack of foam stops play for now. I've ordered a 1200 x 600 x 300mm block. I've scaled up Mike D's Big Easy to 82" span and will give the wings and tail a bash once foam arrives.

I'll stick some plcs up shortly

Cheers

Alex

Phil B27/11/2019 00:46:34
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168 forum posts
161 photos

How do folks veneer the cut foam wings?

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