Freaking fantastic gear, skills and project. No matter what it ends up sounding like I have a bad case of aluGAS now.
Freaking fantastic gear, skills and project. No matter what it ends up sounding like I have a bad case of aluGAS now.
using an english wheel is a true art. it's all done in mid-air and yet the skilled worker produces very accurate work. not for the hamfisted!
When I see people doing beautiful, smooth, complex shapes using shotbag, dollies, hammers and slappers -- that's art. The Ewheel makes a lot of that very easy.Originally Posted by Custom 5
That's the tough part, making accurate shapes. The top and back are fairly complex for panels that only have 1/2" of shape. The lower part is a nice smooth dome, almost round. The waist is almost flat between the pickups and has a lot of shape near the rim. The horns are in a confined area with an unusual shape. All three areas need to blend together smoothly.
If you look at the distance between the contour lines, you can see they're fairly evenly spaced in the large area below the pickups. The area between the bridge pup and the rim compress them together. That's my challenge area.
I've been struggling with the waist area the last few days, trying to get the panel to lay on the table without the waist section being too high. The image above shows what the panel wants to do naturally when you put a smooth, even amount of shape into it. It's a learning experience for sure.
I've made some simple cavities in MDF to form the horn area that will allow me to stay away from there with the wheel and planishing hammer. It's very difficult to see what you're doing and even though I was able to do it for the test horn, it could have been better and more consistent side-to-side. My MDF forms will be used to hydroform those sections instead of using a hammer -- that way they've smooth to start with. I'll have to make a new form for the one on the right. I used that course MDF material and it has hard spots that translate into bumps and valleys in the part. The fine-grained MDF is easier to work with.
Hydroforming is pressing the metal into a cavity using a fluid under pressure. The fluid acts as the punch, the cavity is the die. The fluid can be air, water, oil or even rubber. I use rubber because it's not messy like the others and you don't have to spend any great effort to confine it. What I'll do is place my MDF form on a strong plate in the hydraulic press, followed by the metal blank, a couple of sheets of 1/8" rubber and another strong plate. Then you simply smash the whole sandwich with great force. The rubber first flows from the flat areas into the cavity and as the pressure increases, the rubber forces the metal into contact with the cavity's full shape. The excess rubber tries to squirt out from under the top plate but only after it has formed the shape in the metal.
............Bill
Wild stuff.
Probably the most intense DIY guitar project I've seen unfold.
If this aluminum thing catches on, we may start seeing thread titles like, "5086 vs 5052."
I don't know which one would be Ginger or Mary Anne.
Seeing arch take shape makes me wonder, did you ever consider buying a cheap 335 clone, and making some sort of negative mold/jig of it, to pound the back and top arches into shape?
"Well, I used to be disgusted, now I try to be amused..."
Elvis Costello
Yeah, I did price Epi versions and they can be had for less than $300. I don't know if the" Made in Asia" ones are the same or not but it would be very cheap and easy to tool this accurately if they were. I could also use this prototype as a basis for tooling. If I want to leave the material in -T6 temper there would be springback to consider. Or I could use -T0 material and get the parts heat treated. Or maybe -T4 would be a nice compromise that wouldn't need to be heat treated. Of course I won't need to worry about tooling or tempers unless there are people with money wanting them. That seems unlikely........Bill
Hmm, it seems a post of mine got deleted or never posted. I was asking about the limits of hydroforming. I thought it was a cool idea, and was wondering if one could hydroform the entire top or back.
"The other Shaltanac's joopleberry shrub is always a more mauvy shade of pinky-russet."
"there's NOTHING WRONG with a live penguin, but...I expected a hamburger!"
Yes, you could do it all at once. If it were -T0 temper, it would go pretty easily and you'd get a part that closely followed the die. T6 would spring back a lot. That would require much more die development. Either way, you would need a big press or another way to generate enough PSI on the panel to yield it.
This was a very large and deep part done using a well supported fiberglass die and a thick steel plate for the top. The stack was -- fiberglass/concrete die, metal, rubber gasket, top plate.
The force came from a portable hydraulic jack pump (or did they end up using water??). Anyway, the force = fluid PSI X surface area. My 25 ton press has a pump that has plenty of pressure but not much surface area in the cylinder. If you use the entire surface area of the part instead if the surface area of the hydraulic cylinder, it's easy to make metal yield.
If I were going to build 5 or 10 of these guitars, this is how I'd do it......Bill
Last edited by cwilliamrose; 07-25-2009 at 02:41 PM.
Would you have to temper it harder after forming so it would keep it's shape well?
"The other Shaltanac's joopleberry shrub is always a more mauvy shade of pinky-russet."
"there's NOTHING WRONG with a live penguin, but...I expected a hamburger!"
Yes. My fear would be it getting dented easily. This still going to be an issue anywhere near the welds but those areas are stiffer due to their shape. The large gently shaped areas might be prone to dents if left in T0 condition. I'm not sure about this being an issue, it's my best guess. There may also be a tone difference between T6 and T0 tempers. T6 could be good or bad compared to T0 or it could be about the same.
I just feel more comfortable with a stiffer, springier panel......Bill
I hear ya, so would I. I believe a softer metal would vibrate more freely and attenuate more frequencies then a harder stiffer one... but i could be wrong. This translates to warmer tone vs sustain, i think.
"The other Shaltanac's joopleberry shrub is always a more mauvy shade of pinky-russet."
"there's NOTHING WRONG with a live penguin, but...I expected a hamburger!"
A quick update. I have been doing little test panels, talking to experienced metal shapers and doing some thinking about what this panel might respond best to in terms of technique and the order in which things happen.
I decided to try working on the area of the bridge pickup and waist because it seemed to get out of place quickly. I figure if I can get some shape in that part of the panel and keep it from curling, the rest should be OK. I worked the area inside the marks first and tried to make sure the edge went down (away from the viewer) instead of up. It seems to be working.
Here it is in the buck after doing a lot of passes in the waist area, then moving to the larger area below that. There are some small gaps in the lower part and the waist area needs a bunch more shape.
It's a little easier to see where I lack shape from this angle. The bottom slat left of center needs a little right about where the short slat crosses it. Above the second slat from the bottom all the way to the neck needs more shape -- maybe 3/16" in some spots. The horns haven't been touched yet. Overall, the bottom half is very close to nominal and I have to be careful not to go too far.
From the back you can see the overall smoothness better. I added some adjustable clamps to hold the panel in place. It doesn't take too much effort to get it down to the buck which is good because that means the part may behave better during welding.
I'll do a more detailed sequence for the other panel, I'm just making sure this one is a keeper (the first one became a test panel)......Bill
"The other Shaltanac's joopleberry shrub is always a more mauvy shade of pinky-russet."
"there's NOTHING WRONG with a live penguin, but...I expected a hamburger!"
just too cool!
Here is the panel as of a few minutes ago. Most of the needed shape is there. I still need to do some smoothing and the transition to the horns (which were hydroformed) isn't done yet. Also, the panel is "out of arrangement" meaning the shape is there but the panel is biased such that it doesn't just lay in the buck, it needs a bit of force to hold it to it's proper shape. I'm not sure how much I can do there but I'm too tired to worry about it today.
Monday I'll work on the things I mentioned and anneal the edge so it can be flattened, trimmed and rolled (then a final trim). Hopefully it will cooperate and behave itself for me...........Bill
I love it, I want one!
Thanks Tommy,
Got any like-minded friends? '' If this thing turns out to be real.....
...Um yeah. But there is no way I could afford one, as I have no job.Thanks Tommy,
Got any like-minded friends? '
"The other Shaltanac's joopleberry shrub is always a more mauvy shade of pinky-russet."
"there's NOTHING WRONG with a live penguin, but...I expected a hamburger!"
Me too. I wasn't building it, I couldn't have one either.....Bill
BILL,
When's the next reality season for your "master build"! We're waiting for updates!
Jesse
Old Rockers never die; we just fade away! 会長
Yeah, updates!!! :)
Fuzz is proof God love us and wants us to be happy. - Franklin
http://www.frankdenigris.com
I've been putting off the updates because I've been dealing with nitpicking the back panel and building tools and fixtures -- boring stuff.
The back panel is really close but there are things I don't like and probably won't change (the horns have a little too much shape). Other things need to be massaged a bit. I had the panel in the car to show Kathy last Friday when we went out for burgers and beers. I brought it into the bar at her urging and it looked good to everyone but me.
I have the clamp block made for rolling the corners. I was never any good with an Etch-a-Sketch but I manged to do this OK using the X & Y wheels on the milling machine;
The cavity is just clearance for the shaped panel. It doesn't have to be accurate but I wanted to leave as much wood as possible so the block would remain stiff and strong. What does need to be somewhat accurate is the flat outer area -- that's what clamps the flat part of the panel's edge so I can roll it around the form block. If I didn't have this clamp block, it would be difficult to hold the panel in the right spot and keep it flat too.
Here's the panel as it looks today from a couple of different angles;
The Sharpie marks are areas that need attention. The black outlines need to be raised, the dashed ones need to be smoothed. I did some polishing to help me see the problem areas. The dullness you see inside some of the marks is from the English Wheel which takes some of the shine off because the anvils aren't perfectly polished.
Most of this looks fairly smooth based on the reflections.
Another angle. I can see some problems in this photo on the left side where the panel narrows. It's much easier to see this stuff when it's in your hand and you can move it around and watch the reflections change. It's also not sitting dead flat. I wish it was better but I think it may be OK as-is.
Some of the problem areas are difficult to reach with my big English Wheel. I'm making a tiny one just for those areas;
It's about 11" long and uses two ball bearings as anvils. Hopefully I can get enough pressure to smooth some of the problems around the edges of the panels. I'll finish it in an hour or two and give it a test run.
Once I get the panel smooth and fair I'll clamp it between the form block and my new clamping block and work the edges around the radius. Then I need to carefully trim both the rim and the back so the edges met closely without big gaps. Any gaps will tend to draw together during welding more than the places where there's a good fit. I'll document that part of the process soon.............Bill
So cool.
Hey, get rid of those bungees on that S1 and covert to spring steel. I had a set break and it cost me a prop, a crank and a pair of spade plates . ( And my dignity.) Oh well, I now have a nice Sensinich clock over the fireplace.
Must've greased it because they broke taxiing after the landing!
"No harmonic knowledge, no sense of time, a ghastly tone, unskilled vibrato, and so on. Chuck is one of the worst guitar players I know" -Gravity Jim
Why the rounded over edges? that seems like a huge amount of work for not much benefit. (IMHO)
Nice job Chuck. It had to be a good one!
The airplane in the photo is no longer. It had aluminum gear on it when it perished. I flew a friend's S1 (different airplane) to the Nationals one year and it had bad bungees. It was OK (well, marginal) when flown light for practice but loaded up with full fuel, baggage and my big frame -- not so good! When I got to Sherman the bungees were so weak they were unable to pull the gear up into place unless I got out and removed the baggage (and didn't fuel it). Then you could push it for about ten feet and the gear would seat on the rubber bumpers. Those bungees got changed before the owner flew it again.
The S1 in the photo was an exceptional airplane, I believe it was the last S1-S Curtis made in Homestead before the factory in Afton cranked up. It originally belonged to Bill Thomas and was flown in at least one World Championships (probably '72 or '74). I loved that airplane.....
It's the only way I know of to help control the warpage that wants to happen during welding. Putting the weld joint in the center gives you an inherently stiff shape on both sides of the weld. Beyond that, it looks cool to me and it's something you don't normally see in a hollowbody design. This body will have very little metal that could be called "flat". Mostly it's either bent or compound curved. I think it will look more flowing than it would with sharp corners............Bill
I've got some ideas for the finished product.
Carbon Fiber pickguard. Dimarzio Chrome plated PAF's, Graphite neck.
Bill,
You should sell your work of art to the Nashville or Memphis museums!...it's going to be one of a kind! ... or try to get an art commission to build a big one for display!
Old Rockers never die; we just fade away! 会長
Gee, I flew in the Nationals in Sherman back in 1980! Grayson County Airport, right? That was back in the days of the A.C.A. Iwas wondering if that was an S1-S, from that angle I can't tell if the fuse has the stretch.
"No harmonic knowledge, no sense of time, a ghastly tone, unskilled vibrato, and so on. Chuck is one of the worst guitar players I know" -Gravity Jim
Cool Jerry, what's our budget? I seem to remember Chuck saying he'd kick in 5 for a CF neck. We'll need a bit more than that!
I've got some ideas for the finished product.
Carbon Fiber pickguard. Dimarzio Chrome plated PAF's, Graphite neck.
I'm thinking no PG for this one, let the metal show. I have some Giby nickel PAFs for starters. I plan to use connectors on the pups so I can change them without major disassembly. Who knows what it will want pickup-wise. I'll need to get a lot of players to experience it, I'm nowhere near qualified to develop it's tone............Bill
No one from Gibson has contacted me yet. They must be waiting for it to become real.
Yeah, Grayson County. The bungee trip was probably '76. I was flying Intermediate at that time (placed third, blah). I think I was at the Nats in '80 (or maybe it was '81), I flew my girlfriend's S1-C out there for her. She probably would have won Intermediate that year had we gotten hammerheads figured out for her. I could do 'em really well in her airplane but I couldn't get my (actually Bill Thomas') simple technique across in time for the contest. I judged Unlimited and Advanced but wasn't flying competition anymore.
I enjoyed the ACA contests. Fun bunch of people, laid back, relaxed. Things were never the same after the IAC took over.
What category were you flying? How did you do?......Bill
I was a novice class guy then. I did OK, but got beat by a guy in an aerobatic Bonanza! The only girls I remember from back then were Judy Phile (sp?) and Averil Browning.
"No harmonic knowledge, no sense of time, a ghastly tone, unskilled vibrato, and so on. Chuck is one of the worst guitar players I know" -Gravity Jim
I remember Judy Phile but not Ms Browning. I met my then girlfriend at an aerobatic contest in Homestead. We had a few ladies when I was flying; Debbie Rihn, Patty Nelson, Betty Stewart and Paula Moore come to mind.
The old joke goes something like -- Why do you fly competition akro? Is it for the money, the fame or the chicks?
How did the guy keep the Bonanza in the box?
....................Bill
The Bonanza guy used it all, but stayed in there. I have to admit, I never saw an airplane carve such beautiful lines. And just standing there watching a Bonanza do a snap roll is a mind-altering experience. I remeber though, every tiime he dropped the nose everyone held their breath. That slippery bird with the gear up looked like it wanted to go Mach 1 pulling out of a hammerhead.
"No harmonic knowledge, no sense of time, a ghastly tone, unskilled vibrato, and so on. Chuck is one of the worst guitar players I know" -Gravity Jim
Marion Cole did a nice airshow routine in a Bonanza but he had more room to work with. He had that thing at redline (at least) and it looked good. That said, I liked Bob Herendeen in a Glasair better. Faster, smaller, same power, suburb pilot.
Since I started working on the back panel, one thing has been an consistent issue that didn't seem to have a good solution -- keeping it flat around the rim. It's not so far off being flat that I can't make it flat with moderate force but I just know this will come back to haunt me after welding. Finding out I was right to worry isn't how I want this to go. What I need to do is to stress-relieve the panel while it's rim is flat, then weld it.
A few years ago, my boss and I were talking about forming aluminum and he made an interesting statement: If you could get an aluminum sheet to around 600°F, you could vacuum form it like plastic. The reason is that aluminum loses the majority of it's strength at that temperature and becomes "plastic". That means it will take a shape with minimal force and retain that shape when the material returns to room temperature. Cool I thought. But how do I make use of this?? In a real-world application you would have to heat the sheet and the tool so the process could be completed before the aluminum cooled. But you couldn't take the part off the tool until it cooled. Not very practical for someone in his little machine shop.
While I was annealing the rim I was remained of this property of aluminum. I noticed the part going limp well before the carbon burned off. Just the weight of that long part was causing it to deform when it got hot.
I been thinking about clamping my panel to a steel plate so that the rim is flat and sticking it in my wife's oven cranked up to max heat. (which turns out to be 555°F in this case). It might just be enough but I needed to test it. I had made some small guitar blanks out of .032" thick sheet to test some techniques and one of them has a nice curl just like my real panel. Today I flanged the rim of my little test panel, found a piece of thin steel sheet and some clamps. The rim was only clamped in seven spots but it was good enough for a test. I had Kathy pre-heat her oven while I drove home. I stuck the assembly in the oven for 15 minutes and then let it cool.
She used the hot oven to cook some potatoes for dinner, no wasted heat!!
When I took the clamps off, it didn't move. It stayed nice and flat. 555°F is enough! The really neat thing about this is that the aluminum did not lose it's temper. That's because the anneal temp is 800°F, well above the temperature at which it loses it's strength. I had done a really quick and dirty flange job and actually over bent the flange a little. It was another part of the test. Where the clamps put strain on the flange from being forced flat by the clamp, those areas stayed flat too. That means when I do this with the real panel the flange will come out as I want it instead having to tweak it by hand.
One thing did happen that's a minor problem -- it buckled a little where the horns join the body. It's the same thing that happens when I flatten the horns on the bench (which requires I rework that area). I think I can put some shapes under the horns that will keep that area from buckling.
This is really exciting. In a way it's a crutch to make up for my lack of experience in making the panel behave as I want it to. So be it. A good part is more important than the technique used to make it. All's fair in love and panel beating.........Bill
Worts & All, episode #38;
In my last update I discussed stress relieving the panel to make it lay flat around the rim. I made the fixture for this and tested it on my back panel.
The base plate is 1/4" steel, the clamp plate is 11ga steel. The base plate is drilled and tapped for #8-32 screws. The clamp plate is a ring that follows the shape of the flat part of the panel and is open where the panel has shape. The edge of the opening is raduised so it doesn't mark the panel.
The panel has been filled to prevent buckling which seems to happen along the lines I marked on the image. I was also concerned the panel might do something unpleasant in the entire top half so I filled it to just past the waist. I used modeling clay, the type you would fire in a klin. It's easy to work with, cheap and doesn't mind getting hot. It's typically fired at almost 2000°F so our 555°F oven won't bother it (it won't fire it either, just dry it thoroughly).
Here it is all clamped up and ready to be baked. It came out nice and flat like my little test panel and didn't buckle through the horns. One thing I noticed was the clamp plate didn't want to stay flat when the screws were tightened because I didn't put any panel-thickness stand-offs around the edge like I had planned to do. I added them after the first pass through the oven.
After the fixture modification and another pass through the oven I noticed the panel looked different, deeper than before. Not good.
But I decided to go ahead and do the corner radius and trimming anyway. This is the setup for tapping the radiused edge down. My steel table has a slot in it and some tapped holes -- I made use of both to clamp the panel between the form block and the clamping block. Works good. Forming the corner radius is pretty much like doing the rim, just working around the block a little at a time with wooden and plastic tools until it's all done. The edge has been annealed so it's nice and soft.
This is the result. The edge looks good but the panel has too much shape -- or maybe the wrong shape in some spots. It's about 3/4" at the peak when it should be just over 1/2". I could just use it as-is but the top has to be correct for the neck, pickups and bridge & tailpiece to work properly with each other.
What I think happened is the second trip through the oven was done without the clay filler and the flat-ish area where the pickups mount got round and raised up. There may have been a bit of extra shape before that due to my many step fight to get the panel's curl under control. I think the stress relief part of the process needs to be done earlier in the program and maybe several times. I also think I may have less of a problem with curl in the future as I gain experience. In any case, doing the oven trick early allows me to control the panel during the shaping and it will fit the buck better.
This is my little trimming scribe. It works good. I put some magic marker where the scribe would be doing it's thing and I got a nice visible line to guide my trimming. I'm not sure the scribe is adjusted just right but the idea and the method are good.
So, will I use this panel in the body? At this point I'd say no. I may try bringing it down a little where it's too round and see where that puts me. The time it takes to do the next panel will play a part too. I expect it to go fairly quickly now that I know I can do it (definitely not a given when I started this project) and I know at least one way to keep it flat where it needs to be flat. I have a bit of confidence in the results............Bill
wow. this is starting to get good
Not much of an update here but there are things going on.
I've been testing some techniques for low volume and low tooling cost production of aluminum panels. What I'm doing might be patentable. It might also be dangerous if not done carefully. My testing involves a 4" dia. disk formed into a bowl-shaped die. I have more tests to run but it's looking promising....
I'm also trying to understand why my panels pick up extra shape when I stress-relieve them. I believe it's mostly due the differential thermal expansion between the aluminum panel and the steel fixture. It works like this; I load the fixture at room temperature and when it heats up the aluminum and the fixture expand but at different rates -- the ratio is 2.12:1. When the panel is firmly clamped in the fixture the extra length goes into additional rise and when it cools the panel captures some (most) of that rise. An aluminum fixture base is most of the answer. If I use an aluminum base the panel heats quicker than the thick base and a small amount of the same problem occurs -- maybe 20% of the aluminum/steel combination. I'm not sure it's worth $100 to buy an aluminum plate for this fixture. Magnesium would be even better since it has a slightly higher thermal expansion than aluminum. Probably won't go there either....
Or I could try clamping it very gently so the panel can move a little. That might work too. There are a few other things I want to try just to fully understand what's happening but the technique is useful as-is.
I have a reference guitar now. It's an Epiphone Dot Deluxe VS. Kathy kinda' talked into it because she thought it looked nice. And it came with a hard case which I can use for my aluminum guitar. It's amazing what $300-400 will buy these days.
It's main purpose is to guide my final shaping of the panels and clarify a few details on how the parts are set in the body. Beyond that it will serve as a comparison for the sound I get from my project guitar. I don't intend to try to make mine sound like a wooden one but I do want a similar design as a reference.
I have already noticed the shape is a bit different than my project's body -- the horns are wider. They measure about 11.3" max where my plans show about 11.12. The scale length is very much like my two bolt-on Epi necks, they all measure about 12.39" nut to 12th fret. I know some of the 335's are shorter -- more like 12.31". Balancing the Epi Dot on a paper towel roll, the CG is at about the bottom edge of the neck pup. My CAD model is about 1/4" higher than that. I need to get a more accurate number for the Epi but I'm certainly in the ballpark.
Here's a few photos of the new "tool";
I can keep the Epi or peddle it on eBay when I'm done. It is kinda' purdy.............Bill
You've certainly got more patience than I Bill. If I got that far with it, it'd be "Git 'er Done!"So, will I use this panel in the body? At this point I'd say no.
Looking good!
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