Jump to content


Welcome to the eG Forums!

These forums are a service of the Society for Culinary Arts & Letters, a 501c3 nonprofit organization dedicated to advancement of the culinary arts. Anyone can read the forums, however if you would like to participate in active discussions please join the society.

Photo

Home made guitar cutter


  • Please log in to reply
58 replies to this topic

#31 Tweety69bird

Tweety69bird
  • participating member
  • 462 posts
  • Location:Montreal, QC, Canada

Posted 14 March 2007 - 05:09 AM

David,
I am so impressed by how nice your platform came out with all the 1/4" cuts. Everything is sooooo straight! Did you go over it with a brush to help remove the extra fibers from between the cuts? I don't know what a fence is, but I'm sure my construction-savvy better half will know what it is, and I'm sure he has a miter guage. I am so going to try to make one of these. Anyone I speak to that's not into pastry and try to explain what a guitar cutter is can not believe how expensive they are. I think they think I'm lying! I couldn't believe how much a sugar box was, so I made my own for a fraction of the cost. Thank you for sharing your experience with us! :wub:
Don't waste your time or time will waste you - Muse

#32 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 25 March 2007 - 08:35 PM

Last weekend I made my first attempt to assemble the whole frame. I started by clamping the four sides to the wood form, then heated up one of the joints. The first thing I noticed was that the big gap I was worried about slowly shrunk as I heated the piece. In fact over the ten minutes it took to get it hot enough to melt the brazing material the short side (1 foot) expanded about 1/4". I worked both ends of the short side but had trouble filling the gap in the second joint. It just wouldn't stay filled over the full length of the joint.

Finally I left the piece to cool down and discovered the second problem. It contracts as it cools and trapped the wood form as it did so. In addition it must have weakend the joint because it broke free a couple days later.

I figured the problem was that even with MAPP gas the flame just wasn't hot enough to get the joint up to temperature without heating the entire piece. I would require an oxygen flame and that meant buying a welding kit. I was about ready to drop the project but I found an inexpensive oxygen/MAPP gas torch kit. It was only $10 more than a simple MAPP gas torch so I bit.

I tried that tonight. Unfortunately I found that even that flame won't heat the joint enough to melt the brazing rod without heating the entire piece up. I believe a big problem with my design is that the large pieces of aluminum are too good a heat sink and just drains the heat away from the joint. The brazing rod isn't quite as easy to use as the instructional video would have one believe. Perhaps that is just because I'm not an accomplished welder to begin with.

So once again I'm stuck. It's getting to the point where even if I do eventually complete a frame it may take more skill and equipment than my original design goal of being able to be built by any reasonably handy person with a few inexpensive tools. I am sorely tempted to take Kerry up on her discount and order a commercial cutter so I can get back to making chocolates.

#33 alanamoana

alanamoana
  • participating member
  • 2,738 posts
  • Location:California

Posted 25 March 2007 - 11:50 PM

sorry about all the roadblocks david j.!!

i'm extremely impressed with the progress that you have made, but it does seem that even as expensive as a commercial guitar can be it might end up being cheaper in the long run.

i wish i had a reason to buy one, because i'd do it in a second. they're great for cookie dough as well as ganaches and everything else. the labor and cut down on waste is incredible.

#34 Lloydchoc

Lloydchoc
  • participating member
  • 35 posts

Posted 26 March 2007 - 08:31 PM

Wouldn't it be easier to take it down to a shop that can do TIG welding and have them weld it up in about a half an hour?

#35 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 26 March 2007 - 09:06 PM

Wouldn't it be easier to take it down to a shop that can do TIG welding and have them weld it up in about a half an hour?

View Post


What would be the cost of welding up four frames? For reference of how many joints ther are, my design is up at the top of this thread.

If we are talking about professional welding though, I would alter the design to use steel for lighter weight and less bulk. Probably square stainless steel tubing for the sides and some form of bar stock for the ends to hold the bolts.

#36 Lloydchoc

Lloydchoc
  • participating member
  • 35 posts

Posted 27 March 2007 - 07:12 AM

Use the same design that you have. I had some aluminum frames TIG welded for $10 each. I went to a shop that was set up to weld aluminum frames so they didn't have to figure anything out.

#37 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 28 March 2007 - 10:32 PM

Progress continues: I figured out how to braze the frame!

Posted Image

I used a pair of pipe clamps insulated from the metal by bits of wood so they wouldn't drain off heat from the work piece. I left out the center wood frame and just pressed the long sides into the short sections. That kept the expansion in check and prevented contraction from pulling the newly formed joints apart.

I used too much of the filler rods and made a bit of a mess the first time through, but the next time should be much neater.

I started with both the MAPP torch and the MAPP/Oxygen torches, but soon ran out of Oxygen in the latter and continued on with just the garden variety hardware store MAPP torch. I realized that the simple one is all you need. The trick is to wait long enough for the work piece to come up to temperature, and that can take several minutes. I suppose two regular torches would speed that up quite a bit but it isn't necessary.

Here's a closeup of one of the joints:

Posted Image

This particular frame is going to be a tight fit for the cutting board so I'm just going to make it my learning piece. Future frames will be cut 13" wide instead of 12" to give a good 1/2" clearance on either side of the cutting board. I'm also going to cut the pieces on the tablesaw to get perfectly square edges which will improve the look of the joints and ensure the whole frame squares up nicely.

The next task will be to drill and tap the holes for the bolts, drill the holes for the wires, and string it all up. That will be the proof of whether or not the design is strong enough.

#38 Kerry Beal

Kerry Beal
  • participating member
  • 9,996 posts
  • Location:Ontario, Canada

Posted 29 March 2007 - 05:41 AM

That is a good looking joint. I think your cutter is going to be sucessful!

#39 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 06 May 2007 - 12:05 PM

It's been a while as I have figured out how to get the holes drilled in the cap screws.

I first tried to drill by hand, but that was a dismal failure. I tried to use a center punch to get a dimple to start the bit in, but the bolts are stainless steel and refused to mark. Next I used a Dremel tool to grind a small flat on the bolt first and that sort of worked but not very well. I dulled a couple bits on the bolt before having to take a break and think.

I gave up momentarily and ordered bolts though Design Realization for $3.84 a piece, but ended up canceling my order when I found out shipping would be $24 if I wanted it in a week or $18 if I was willing to wait for three. That would have brought the cost to $62 for ten bolts and I just couldn't bring myself to double the cost of the cutting frame just for the bolts.

So it was back to research. I knew people drilled bolts for saftey wiring so I took that track. That was when I found this handy little jig:

Posted Image
Just what I was looking for...

I read that I needed a Cobalt drill bit to cut through Stainless Steel. This is supposed to be used with a 1/16" bit so I ordered the jig and went to the hardware store to pick up the bit.

My first attempt was to clamp the jig in a vice and hand hold the drill. That's how I snapped off two bits before giving up once again...

More time passed as I contemplated buying a drill press to cure my hand holding problem, but I just didn't want to add that expense to the project. Then I recalled a hand held drill jig/press I had that might do the trick. The problem was that it had to be pressed against a flat surface to work and the bolt jig was definately not.

Then I got the bright idea to clamp the jig between a couple boards cut for the purpose:

Posted Image
That gave me the flat surface!

Posted Image

So now I could drill.

I filled the tiny hole with as much oil as I could coax down and coated the bit with more oil before placing it and starting it up. The first bolt drilled through in about 20 seconds and I was elated. The next bolt I tried took a bit longer. I manged to break the tip of the bit off in another bolt. I think one bit is good for two or three bolts, but I didn't keep strict track of it all. Once you find the bit spinning without cutting don't just replace the bit and keep going. The heat work hardens the Stainless Steel and you will just end up ruining the next bit. I verified this so you don't have to. I hope to get three or four bolts per bit once I get the hang of how much pressure and what speed to run the drill at for optimum cutting. That would put the cost per bolt at $0.25 for the bolt itself plus $0.73 to $0.55 for the bit.

Posted Image
The finished bolt

I quickly strung a couple wires in the frame to test it out and that is when I discovered a design flaw.

No, the frame did not collapse under the strain. What happened was that I couldn't draw the wire as tight as I wanted. I turned the bolts and drew the wire into place, but once it was drawn tight enough to make the two 90 degree bends it wouldn't pull through any more. The bends work hardened the wire and it wouldn't flow past it. I should have realized that is what would happen, but Llyod had and example of it working so I didn't give it a great deal of thought. The wire will tighten fairly well that way, but just not as much as I would like. So now I'm looking for a half round rod I can use to greatly enlarge the radius of the 180 change in direction for the wire. I think a 1/2" diameter would do well. I haven't been able to find that for purchase anywhere so I might end up having to split a full round rod on the table saw.

#40 Kerry Beal

Kerry Beal
  • participating member
  • 9,996 posts
  • Location:Ontario, Canada

Posted 06 May 2007 - 12:54 PM

Glad to see you are still at it and that it is going reasonably well. One neat thing is how much you are going to learn about metalwork doing this.

I bought a little tiny cheese cutter on e-bay a couple of weeks ago. Just waiting for it to show up. It has 2 sets of wires at 90 degrees to each other, with the wires spaced 7/8 inch apart. Should made a interesting teeny guitar.

Keep us posted.

#41 choux

choux
  • participating member
  • 282 posts
  • Location:Whistler,BC

Posted 08 May 2007 - 04:28 PM

Hi David,
I've been reading with interest, and have been collecting materials. It was difficult to fing a thick cutting board, but I happened to run across one at my local housewares store. I have a question, what kind of blade did you use on the tablesaw to get a thin cut in the board?
My husband is in to RC(remote control cars), and suggests you look at 'rigging couplers' for RC airplanes. They are pre-drilled threaded shafts that may work for tensioning the wires.
Also, what kind of wire are you using?

#42 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 08 May 2007 - 09:21 PM

Hi David,
I've been reading with interest, and have been collecting materials. It was difficult to fing a thick cutting board, but I happened to run across one at my local housewares store. I have a question, what kind of blade did you use on the tablesaw to get a thin cut in the board?
My husband is in to RC(remote control cars), and suggests you look at 'rigging couplers' for RC airplanes. They are pre-drilled threaded shafts that may work for tensioning the wires.
Also, what kind of wire are you using?

View Post


Hi Choux,

I'm happy to hear that others are interested in my design. I've got ideas on how to make a easier jig/clamp for the initial brazing of the frame so stay tuned for that. Once I get done with the proof of concept I'm going to make another correcting for all the inaccuracies and problems I exposed with the first attempt. I'm also going to take more pictures including video to document the process.

I found the cutting board online for somewhere around $30 for a 12x18x1" board. You'll find lots of suppliers if you just Google "HDPE cutting board".

After searching the web for a couple days without success I found a "thin kerf" blade at Home Depot. I left the blade over at my friends home since it is his tablesaw I am using so I can't give you specifics right now. Basically it's got a 1/16" kerf and it's about 8" or 10" diameter. I'll try to remember to stop by the store again and see if I recognize it. If so I'll post the details.

I took a look at the rigging couplers and they look fine but for the fact that they don't have a socket in the top with which to tighten them. I believe they are meant to spin into a coupler freehand, then run a cable through the hole and crimp it in place. The guitar cutter needs something more like a tuning pin that can be turned under tension.

For the wire I bought 60lb test Stainless Steel trolling wire from alltackle.com. It comes in a 600' package which means I've got far more than I need. I'd be happy to send you some. There is no way that I'm going to use half of it.

The HTS-2000 aluminum brazing rods are another item that several people could probably split an order of. When I get my second frame brazed up I will measure how many rods I use so others can arrange a group buy. It shouldn't take but a fraction of the 1lb minumum order so people can split it and keep costs down.

The bolt jig for drilling is called "ALLEN SAF-T-BLOK STD" at aircraftspruce.com.

That's all I can think of for now.

David

#43 choux

choux
  • participating member
  • 282 posts
  • Location:Whistler,BC

Posted 09 May 2007 - 06:10 PM

Thanks for the info David. We're thinking of using stainless steel tubing for the frame, it may help with your problem of the wires not bending. I'm only going to be making one frame, and 1" slots on the board since that's all I use now anyways. I have a friend who does welding so I'm going to get him to help. I'll post pics, I hope to get started soon.

#44 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 11 May 2007 - 12:32 PM

I have a question, what kind of blade did you use on the tablesaw to get a thin cut in the board?

View Post


Choux,

The sawblade I used is from "Ridgid" and is golden in color as it has a "Titanium Coating"and also has "LASER CUT-REDUCED VIBRATION TECHNOLOGY" (basically curling slots cut in the blade).

The blade is 7 1/4" in diameter with 24 teeth and the kerf is a mere 0.059”. The item number is R0724R

Here's a link I found:
http://www.ridgid.co...lades/index.htm

#45 panini

panini
  • participating member
  • 11 posts

Posted 12 May 2007 - 03:50 PM

I totally appologise if I'm repeating someone else. I just did not have the time to read everything w/ mom's day and all.
I have made my own with some great sucess. It does involve collecting old residential ice makers. Even the commercial will work. There are many cube size varieties. Check it out.
pan

Edited by panini, 12 May 2007 - 03:51 PM.

paninicakes.com

#46 Kerry Beal

Kerry Beal
  • participating member
  • 9,996 posts
  • Location:Ontario, Canada

Posted 12 May 2007 - 03:57 PM

I totally appologise if I'm repeating someone else. I just did not have the time to read everything w/ mom's day and all.
I have made my own with some great sucess. It does involve collecting old residential ice makers. Even the commercial will work. There are many cube size varieties. Check it out.
pan

View Post

Have you got any pictures for us to see?

#47 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 15 May 2007 - 06:39 PM

More progress to report:

I've drilled all the cap screws and strung the frame!

Posted Image

I wrapped one end of the wire through a small washer to hold it in place:

Posted Image

The other end went over a loose 1/2" rod, back through the frame, and around the screw:

Posted Image

I didn't have a chance to try to cut the rod in half and found that it works just fine as it is. I was afraid that the combined tension of the wires might bend the frame a bit, but I don't have any evidence of that at all. I installed the wires from the outside in and non of them loosened as the others were put in. That shows the frame could be widened out to 15" or 16" without having to get thicker angle aluminum.

Nuts secure the cap-screws in place to keep them from backing out:

Posted Image

Finally here is a shot of the frame with the cutting board:

Posted Image

I bought some JB weld glue to attach the handle with, then I've got to create the hinge and base to mount the cutting table on.

#48 gap

gap
  • participating member
  • 503 posts
  • Location:Melbourne, Australia

Posted 15 May 2007 - 06:42 PM

Way to go David - all that hard work is starting to take shape!!

#49 Kerry Beal

Kerry Beal
  • participating member
  • 9,996 posts
  • Location:Ontario, Canada

Posted 15 May 2007 - 06:46 PM

Looking good!!!

#50 Chris Amirault

Chris Amirault
  • eGullet Society staff emeritus
  • 19,628 posts
  • Location:Rhode Island

Posted 30 May 2007 - 11:46 AM

Any updates?
Chris Amirault
camirault@eGstaff.org
eG Ethics Signatory
Sir Luscious got gator belts and patty melts

#51 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 30 May 2007 - 09:27 PM

As a matter of fact there has been a bit of progress.


I used JB Weld epoxy to attach the handle to the frame,

Posted Image

and I trimmed the back edge of the cutting table so that the wires would feed into the slots without catching.

Posted Image

I still haven't mounted everything on a base yet, but I couldn't resist trying it out anyway. To do this I placed the cutting table on a couple of books on the coffee table to give it height and held an end of the cutting frame in each hand. I made the mistake of adding a thick foot of tempered chocolate and it set before I managed to get it cut. That meant I had to press fairly hard which stretched some of the wires, but it cut the slab anyway:

Posted Image

I tightened the loose wires and proved that by adding the rod I achieved enough of a radius that the wire would flow easily and could be retightened.

Perhaps next weekend I will attack the base. I had meant to get to it over the long Memorial Day weekend but ended up making two batches of truffles instead.

While it has taken quite a while for me to get this far because I've had to design it as I go, I marvel at just how little effort or expertise it would take to duplicate.

#52 Sebastian

Sebastian
  • participating member
  • 356 posts

Posted 03 March 2008 - 08:51 AM

bumping the thread up in case there's been any developments here that we'd find interesting 8-)

#53 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 03 March 2008 - 12:51 PM

bumping the thread up in case there's been any developments here that we'd find interesting 8-)

View Post


No big developments. I've been lazy about designing and building a base. Instead I've just been using it hand-held and found it works nicely in that I can rock it to cut from the back, then front, then middle. That works out especially well when the ganache is stiff or I miscalculated and let a tempered chocolate foot set up too far.

Right now it's on loan to Tammy. Perhaps she will post her comments.

I have speculated that the whole thing might be able to be constructed with epoxy rather than having to deal with brazing. A slight channel cut in the side rails for the ends of the cross pieces would ensure that the glue didn't have to hold against a shearing force. If that worked it would reduce the skill set required by a notch, not that brazing is all the difficult.

#54 tammylc

tammylc
  • participating member
  • 2,155 posts
  • Location:Ann Arbor, MI

Posted 03 March 2008 - 01:13 PM

Never having used a guitar before, I don't have experience with a real one to compare it to. But even without the base, it made short work of two slabs of ganache for my Valentine's Day production. However, not having as much of the knack with it that David's developed, I think I would have found it cleaner and easier with a base, since I would be better able to take advantage of leverage. But it definitely works as is!

My biggest learning from borrowing David's guitar cutter, is that I don't actually want my husband to make me one, even though he probably could. Because it was way too easy to produce 220 perfect squares of ganache, and way too time-consuming and tedious to hand-dip 220 perfect squares of ganache. Have I mentioned how much I HATE dipping?

So I bought 4 more molds instead, and will up my capacity that way. (I usually make 4 flavors at a time - 3 molded, one enrobed. I'm just going to switch over to all molded except when there's a flavor I really want to do that has to be enrobed, and I'm feeling particularly masochistic.)

Tammy's Tastings

Creating unique food and drink experiences

eGullet Foodblogs #1 and #2
Dinner for 40


#55 Sebastian

Sebastian
  • participating member
  • 356 posts

Posted 03 March 2008 - 02:10 PM

I'm (well, a good friend of mine will do the real work) about to start making two types of cutters, inspired, of course, by your efforts here. one will be a conventional 'hinge' action guitar, the other i think i'm going to take a '4 post' approach, where the corners of the cutting board have vertical guides that allow for a 'screen' to lower on them, effectively cutting both directions at the same time. if the tolerances are tight enough, there shouldn't be any wiggle room and the cuts should be nice. when i get to the point of actually doing it vs drawing it, i'll post pictures 8-)

Edited by Sebastian, 03 March 2008 - 02:11 PM.


#56 David J.

David J.
  • participating member
  • 420 posts
  • Location:Michigan

Posted 03 March 2008 - 02:41 PM

I'm (well, a good friend of mine will do the real work) about to start making two types of cutters, inspired, of course, by your efforts here.  one will be a conventional 'hinge' action guitar, the other i think i'm going to take a '4 post' approach, where the corners of the cutting board have vertical guides that allow for a 'screen' to lower on them, effectively cutting both directions at the same time.  if the tolerances are tight enough, there shouldn't be any wiggle room and the cuts should be nice.  when i get to the point of actually doing it vs drawing it, i'll post pictures 8-)

View Post


It sounds like you are planning on duplicating Llyod's design (which is where I got my inspiration). His works great for the punch style, though I would opt for a single row of bolts in each direction to cut down on the effort required.

I'll be watching for your design and pictures!

#57 ChristopherMichael

ChristopherMichael
  • participating member
  • 132 posts
  • Location:SoCal

Posted 03 March 2008 - 02:58 PM

Just to let you know, if you plan on using that in a commercial kitchen, don't let the health inspector know about it. Wait until they're all gone before you bust it out, because it's not NSF. Shame on all of you for being handy. java script:emoticon(':biggrin:') smilie <---- why isn't this working? its suppose to be a smile

Sorry guys I was just venting a little about my health department.

Edited by ChristopherMichael, 03 March 2008 - 03:00 PM.


#58 tammylc

tammylc
  • participating member
  • 2,155 posts
  • Location:Ann Arbor, MI

Posted 03 March 2008 - 05:43 PM

Just to let you know, if you plan on using that in a commercial kitchen, don't let the health inspector know about it. Wait until they're all gone before you bust it out, because it's not NSF. Shame on all of you for being handy. java script:emoticon(':biggrin:') smilie  <---- why isn't this working? its suppose to be a smile

Sorry guys I was just venting a little about my health department.

View Post


And understandably so. Your health department SUCKS. I've been reading your posts with much sympathy and anguish for you.

Tammy's Tastings

Creating unique food and drink experiences

eGullet Foodblogs #1 and #2
Dinner for 40


#59 ejw50

ejw50
  • participating member
  • 334 posts

Posted 05 March 2008 - 01:29 AM

My biggest learning from borrowing David's guitar cutter, is that I don't actually want my husband to make me one, even though he probably could. Because it was way too easy to produce 220 perfect squares of ganache, and way too time-consuming and tedious to hand-dip 220 perfect squares of ganache. Have I mentioned how much I HATE dipping?

View Post


Well, you could wait for David to 'Alton Brown' an enrober and ask your husband to do that too. Then it might be worthwhile!