The Acoustic Guitar Forum

Go Back   The Acoustic Guitar Forum > General Acoustic Guitar and Amplification Discussion > Build and Repair

Reply
 
Thread Tools
  #1  
Old 01-09-2021, 02:13 PM
dannyds dannyds is offline
Registered User
 
Join Date: Dec 2013
Location: Cambridge, MA
Posts: 9
Lightbulb Pipe for side bending iron

Good afternoon,

I am building a side bending iron using a Wagner Furno 500 heat gun, which can achieve temperatures in the range of 150F-1200F. I plan to build a stand out of plywood and blow the hot air into a pipe with a cap on the end. I have read that galvanized steel should not be used, so I am researching other options.

Will the pipe at the link below stain the wood? It says black-coated steel. Is that the same stuff they sell at Home Depot that I bought for pipe clamps? If so, I know it will stain the wood.
https://www.mcmaster.com/44615K126/

Any other safe, affordable options?

Thank you,
Dan
__________________
Yamaha FG730S
Reply With Quote
  #2  
Old 01-09-2021, 02:40 PM
phavriluk phavriluk is offline
Registered User
 
Join Date: Jul 2012
Location: Granby, CT
Posts: 1,232
Default A thought

When I made my pipe, I searched online metals dealers until I found a thickwalled aluminum pipe of the size I wanted.
Reply With Quote
  #3  
Old 01-09-2021, 02:53 PM
Rudy4 Rudy4 is offline
Registered User
 
Join Date: Oct 2012
Posts: 3,916
Default

Quote:
Originally Posted by phavriluk View Post
When I made my pipe, I searched online metals dealers until I found a thickwalled aluminum pipe of the size I wanted.
Aluminum will stain some woods and iron / steel pipe will also react with certain woods. I use a length of 2-1/2" hard copper pipe fitted with a 1/4" aluminum plug with 1/4" holes drilled in it. The plug was fitted to the inside diameter of the pipe and is anchored with three 1/8" diameter roll pins driven into drilled holes. Capped pipes can heat unevenly as there's nowhere for the heat to go.

I have a couple of similar smaller diameter pipes for tighter radius bends.

I went to a larger industrial plumbing shop and got the pipe for a couple of bucks. I've been using it for several years and it sets up in about 30 seconds. Everything breaks down in seconds and stores flat so it takes up little room in the shop.

Don't forget to make yourself up a backing strap as shown in the photo.

Reply With Quote
  #4  
Old 01-09-2021, 04:28 PM
dannyds dannyds is offline
Registered User
 
Join Date: Dec 2013
Location: Cambridge, MA
Posts: 9
Default

Quote:
Originally Posted by Rudy4 View Post
Aluminum will stain some woods and iron / steel pipe will also react with certain woods. I use a length of 2-1/2" hard copper pipe fitted with a 1/4" aluminum plug with 1/4" holes drilled in it. The plug was fitted to the inside diameter of the pipe and is anchored with three 1/8" diameter roll pins driven into drilled holes. Capped pipes can heat unevenly as there's nowhere for the heat to go.

I have a couple of similar smaller diameter pipes for tighter radius bends.

I went to a larger industrial plumbing shop and got the pipe for a couple of bucks. I've been using it for several years and it sets up in about 30 seconds. Everything breaks down in seconds and stores flat so it takes up little room in the shop.

Don't forget to make yourself up a backing strap as shown in the photo.
Thank you for the advice. What is the thickness of that pipe? Is it easy to bend into an oval shape if desired? The diameter looks bigger than 2-1/2" to me.
__________________
Yamaha FG730S
Reply With Quote
  #5  
Old 01-09-2021, 06:33 PM
BradHall BradHall is offline
Charter Member
 
Join Date: Mar 2012
Location: Windsor, Ca.
Posts: 752
Default

I started with a 3Ē black pipe with a galvanized cap. I do use a propane torch. I always used a blue shop towel between the pipe and wood, spritzing is with water to generate a little steam. It worked, never contaminated the wood. I then got the LMI aluminum pipe and never looked back. Havenít had any contamination issues. I have a friend with an electric one that serves him well. Another friend used a cut off from a sailboat mast that was already oval, with a bbq starter and it works for him, although he only builds dreads. Iím a mostly built it if I can guy when it comes to tools. Sometimes itís just worth it to buy something tried and true. Good luck on your build.
__________________
BradHall

_____________________
Reply With Quote
  #6  
Old 01-09-2021, 09:01 PM
Bruce Sexauer's Avatar
Bruce Sexauer Bruce Sexauer is offline
AGF Sponsor
 
Join Date: Jan 2009
Location: Petaluma, CA, USA
Posts: 6,525
Default

I have used a 6’ long piece of 3” OD iron pipe for 45 years! I also use a Fox bender and an electric violin type hot pipe, but they are recent additions to the Arsenal.
__________________
Bruce
http://www.sexauerluthier.com/

Last edited by Bruce Sexauer; 01-10-2021 at 10:51 AM.
Reply With Quote
  #7  
Old 01-10-2021, 09:15 AM
Rudy4 Rudy4 is offline
Registered User
 
Join Date: Oct 2012
Posts: 3,916
Default

Quote:
Originally Posted by dannyds View Post
Thank you for the advice. What is the thickness of that pipe? Is it easy to bend into an oval shape if desired? The diameter looks bigger than 2-1/2" to me.
The wall thickness of the pipe shown is approximately 1/16", so the actual outer diameter of the pipe is 2-5/8". A "2-1/2" pipe has slightly different outer diameters depending on the type of copper pipe is selected. Type "M" is thinner walled and Type "L" (shown in the photo) has increased wall thickness. The inside diameter is the same between types.

No, type L isn't "easy" to bend, but it could be shaped if that's what you really want. I simply switch to a smaller diameter for tight bends like a cutaway waste.

Ideally you'll have much better bends using the larger diameter because the contact area along the wood will be greater (even though you control heat along the bend by rocking your work) and larger diameter decreases your chance of creating lumps and ridges along the bend.
Reply With Quote
  #8  
Old 01-10-2021, 05:32 PM
printer2 printer2 is offline
Registered User
 
Join Date: Dec 2012
Posts: 4,123
Default

I used a heat gun for a fair number of sides. No problem using galvanized pipe at the temperature we need. I found it better if I let some of the air pass through. Don't put the heat gun right in the pipe as the heat of the pipe will melt the outer plastic. Lost a gun that way.
__________________
Fred
Reply With Quote
  #9  
Old 01-13-2021, 08:18 AM
redir redir is offline
Registered User
 
Join Date: Aug 2011
Location: Mountains of Virginia
Posts: 6,063
Default

Quote:
Originally Posted by Rudy4 View Post
Aluminum will stain some woods and iron / steel pipe will also react with certain woods. I use a length of 2-1/2" hard copper pipe fitted with a 1/4" aluminum plug with 1/4" holes drilled in it. The plug was fitted to the inside diameter of the pipe and is anchored with three 1/8" diameter roll pins driven into drilled holes. Capped pipes can heat unevenly as there's nowhere for the heat to go.

I have a couple of similar smaller diameter pipes for tighter radius bends.

I went to a larger industrial plumbing shop and got the pipe for a couple of bucks. I've been using it for several years and it sets up in about 30 seconds. Everything breaks down in seconds and stores flat so it takes up little room in the shop.

Don't forget to make yourself up a backing strap as shown in the photo.

I've had the exact same set up as you have since 1992. I vaguely remember going to some metal shop and asking for some large copper pipe. When I told the guy what for he thought it was great and just gave it to me. Instead of an aluminum plug I just stick the top of a beer can in there.

As of last year I now use a charcoal lighter instead of the blow torch. But I still just simply mount the pipe in a vice. Simple solutions.

I also added a bending machine to my shop last year.

Reply With Quote
  #10  
Old 01-13-2021, 10:28 AM
Zigeuner Zigeuner is offline
Registered User
 
Join Date: Jan 2010
Location: Northern California
Posts: 1,005
Default Aluminum pipe works nicely.

For the guitars that I've built (9 and working on #10), I've used an aluminum pips that is 4" OD and 3-1/2" ID with 1/4" wall. I heat it with a barbecue torch that is mounted inside and I've use both natural gas form my house and also propane at various times. I monitor the temperature with a digital thermometer and adjust the gas to hold my temperature. (this will vary).

With the wood thin enough, say .090 to .100, the wood bends nicely once soaked for a bit in water.

Works for me. I'd post some pictures but it's very difficult on this site since I don't have a hosting site anymore.
Reply With Quote
  #11  
Old 01-17-2021, 01:45 PM
Brad Howard Brad Howard is offline
Registered User
 
Join Date: Dec 2019
Posts: 2
Default

I use a 3"SS exhaust pipe extension with muffler clamps and some insulation to mount the pipe on a board which I clamp in my vice.
Reply With Quote
  #12  
Old 01-18-2021, 07:12 AM
dnf777's Avatar
dnf777 dnf777 is online now
Charter Member
 
Join Date: Sep 2013
Location: NW Pennsylvania
Posts: 942
Default

If youre near a sailboat shop, they can cut you a short piece of aluminum mast. Round if you prefer, but mine has a slight teardrop profile. Aluminum heats quicker than iron or steel. I give mine a quick brush with medium steel wool before using to remove any ox, and havent had any wood discoloration issues.
__________________
Dave F
*************
Martins
Guilds
Gibsons
A few others
Reply With Quote
  #13  
Old 01-18-2021, 08:33 AM
MC5C MC5C is online now
Registered User
 
Join Date: Mar 2016
Location: Tatamagouche Nova Scotia
Posts: 1,034
Default

I use 3" truck exhaust pipe, probably 16 gauge, squashed into an oval shape. I use an electric barbque starter as a heat source. It was free and it works great.
__________________
Brian Evans
1935 Dobro model 25 resonator
1943 Paramount (made by Kay) mandolin
1946 Epiphone Zephyr electric archtop
1957 Hofner Senator archtop
1962 Gibson Melody Maker electric
1963 National Dynamic lap steel
1996 Landola jumbo
1998 Godin Artisan TC electric
1998 Epiphone SG electric
2010 GoldTone PBR-CA resonator
2015 Evans electric archtop
2016 Evans archtop
Reply With Quote
  #14  
Old 01-19-2021, 11:57 AM
kmanuele kmanuele is offline
Registered User
 
Join Date: May 2017
Posts: 32
Default pipe bender

I used a piece of 2-1/4" steel pipe, about 9" long, pre-threaded on both ends from HD. Added a flange on one end and a cap on the other. Flange is for mounting in a vice.
Got an electric barbeque starter, carefully bent it to fit inside the pipe.
Connected a 1 kW incandescent light dimmer mounted in an outlet box.
Reply With Quote
  #15  
Old 01-19-2021, 01:42 PM
Zigeuner Zigeuner is offline
Registered User
 
Join Date: Jan 2010
Location: Northern California
Posts: 1,005
Default

Quote:
Originally Posted by kmanuele View Post
I used a piece of 2-1/4" steel pipe, about 9" long, pre-threaded on both ends from HD. Added a flange on one end and a cap on the other. Flange is for mounting in a vice.
Got an electric barbeque starter, carefully bent it to fit inside the pipe.
Connected a 1 kW incandescent light dimmer mounted in an outlet box.
I like your idea. I have a nice setup for Gas or Propane with an aluminum pipe, but switching to electric will be much safer since I don't like open flames in my shop when I can avoid them.

Dimmers are OK and they are inexpensive but a few years ago, I found an electric voltage regulator that is very nice as well. I use two of these in a dual track Model Railroad DC Power Pack and they are very linear and precise. With one of these controlling the voltage into a BBQ torch and a digital thermometer, you could set the temperature very nicely. See the link.

Thanks for mentioning this.


https://www.amazon.com/Yeeco-Electro...s%2C225&sr=8-6
Reply With Quote
Reply

  The Acoustic Guitar Forum > General Acoustic Guitar and Amplification Discussion > Build and Repair

Thread Tools





All times are GMT -6. The time now is 05:18 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Copyright ©2000 - 2021, The Acoustic Guitar Forum
vB Ad Management by =RedTyger=