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  #16  
Old 05-24-2016, 04:39 PM
LouieAtienza LouieAtienza is offline
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Originally Posted by littlesmith View Post
You can factor these cheap bits into the price for your client, if they go dull you just throw it away (or keep using it on wood). Make sure the diameter is compatible with your CNC setup.

http://www.ebay.com/itm/1-4-250-CARB...AAAOSwVL1V~was

http://www.ebay.com/itm/381410198364
I actually buy a few tools from that eBay seller... mainly single edge spiral "O" flute in 1/8" and 1/16". While I have used PVD coated burr-routers, they're not as efficient as PCD endnills as far as chip evacuation. Plus you probably don't want to use a burr-endmill on wood anyway for the same chip evacuation problems. I DO use them for plunge-drilling holes in G10 and CF, since PCD drills are just as expensive.

There are companies that do recycle carbide, so I try not to throw used endmills away. But yes, the cost of the tooling (which I get at a discount by surfing eBay) was factored into the jobs; unfortunately I made more money cutting this stuff than building guitars!
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  #17  
Old 05-25-2016, 05:30 AM
littlesmith littlesmith is offline
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Originally Posted by LouieAtienza View Post
I actually buy a few tools from that eBay seller... mainly single edge spiral "O" flute in 1/8" and 1/16". While I have used PVD coated burr-routers, they're not as efficient as PCD endnills as far as chip evacuation. Plus you probably don't want to use a burr-endmill on wood anyway for the same chip evacuation problems. I DO use them for plunge-drilling holes in G10 and CF, since PCD drills are just as expensive.

There are companies that do recycle carbide, so I try not to throw used endmills away. But yes, the cost of the tooling (which I get at a discount by surfing eBay) was factored into the jobs; unfortunately I made more money cutting this stuff than building guitars!
This post is also for @Ethanshin.

I would make a mold that can split open, and build the recess for bindings into the composite part like this (then you dont need to route composites) :



The mold must be able to flip open, because this part has overhang, that means it can not travel up or down to be released out of the mold.

If you make it like this, this type of part can be released without problems (1 hinge and 1 lock) :



Another way to do it without composite routing is like this :



You let the linings stick out on the top and bottom, glue the soundboard and back on, then you route into the linings and soundboard (or back) wood only. The bottom of the binding will sit on top of the composite. The composite has to be sanded on a flat board so it has a 90 degree edge on top and bottom.
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Last edited by littlesmith; 05-25-2016 at 05:52 AM.
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  #18  
Old 05-25-2016, 06:00 AM
littlesmith littlesmith is offline
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Trying to fix the problem of the heat being to close to the part (and warping it again).

I skipped the heat curing of the gelcoat which was not good. Heat curing was recommended on that product.

Now i am making a larger oven to cure the epoxy that is in the fiberglass backing :







Im afraid this wont even hit 60 degrees Celcius, but something is better then nothing right now. This epoxy did not say recommended after the heat cure instructions, so i will assume it`s mandatory.

Edit, this setup maxed out on 45 degrees celcius, i just cut the posts off, all 15 centimeter lower. That will reduce air volume and make the temperature higher then what it was. It can`t be too low, because then the electric heating element will be too close to the mold and it could warp again.
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  #19  
Old 05-26-2016, 06:14 AM
littlesmith littlesmith is offline
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This project failed. The mold is dead. I tried but the 10k loan was just not enought for composites. I am gratefull for the opportunity, but this dream is over. I will be repaying this loan for the next 10 years on this welfare. there is no money for new materials, and im not gonna loan more. Everything is seperating, the gelcoat isnt even bonded to another layer of gelcoat. the gelcoat isnt bonded to the fiberglass. The shape of the resin infusion mold is just too complex to make from wood by hand, you need a CNC routed aluminium mold. I am good, but i`m not a CNC machine.

Thank you everybody that showed interrest. I took the risk and i failed, now i have to pay the price.
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  #20  
Old 05-26-2016, 07:42 AM
lizzard lizzard is offline
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What is the point of failure if you don't, feel it, learn from it, regroup and apply the lessons to the next TRY?

Your upset right now which is understandable. But I suspect you will be back!



Chris
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  #21  
Old 05-26-2016, 08:04 AM
LouieAtienza LouieAtienza is offline
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If I were you, I'd sell that expensive heat blanket, buy some heat bulbs and more resin. You have 8 guitars to build. Don't renege on your promise.

Really, with 10000€ I could have bought a CNC, all the resin, CF, wood, and hardware, and still had enough left over to pay myself. I'd do whatever possible to salvage that mold, fix it, Bondo it, whatever. Get it done.

And, there seems to be people here with a lot of CF experience. Eating some humble pie and asking for advice is part of the process.
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  #22  
Old 05-26-2016, 09:04 AM
lizzard lizzard is offline
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AND, maybe call some of the larger CF builders and try to talk to the techs. You are no threat to their market-share (for now) and i bet someone will talk to you. Valuable insight from experience!
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  #23  
Old 05-26-2016, 10:59 AM
LouieAtienza LouieAtienza is offline
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Looking back, the two toasters possibly giving off too much localized heat, so the mold cured unevenly? That IR heat travels pretty straight... possibly a hair dryer in a port would give a more even heat...
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  #24  
Old 05-26-2016, 11:33 AM
PeterF PeterF is offline
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I feel your pain! I've had big layups go completely wrong on me as well.
I think your problem is the heat. I think I've said before that there is no need to heat cure epoxy at all, unless you're using it in critical, high strength applications. A mold is not one of them! A guitar body isn't even one of them. If I were you, I would forget the 'aerospace grade' stuff and just get some normal epoxy from a normal fibreglass supplier. It will make zero difference to the end product - a guitar is not an airplane!
Also, having voids and bubbles in they mold layup is not a deal breaker. As long as the gelcoat surface is smooth, you're good to go. Again, the mold is not a structural part, so it doesn't need to be treated like one.
I really hope you keep going with this. I'm sure you will be able to make good guitars once you get all the problems ironed out.
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  #25  
Old 05-26-2016, 12:38 PM
littlesmith littlesmith is offline
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I don`t want to be paying off a loan for 13.3 years so i have to find a way to make 8 carbon bodys.

I have one more chance to make a mold with a little bit of material that is left. I can not attempt the big fancy mold anymore, so it will be a small thing. I hope i can make a proper vacuum with it without the double seal channels.
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  #26  
Old 05-26-2016, 12:41 PM
littlesmith littlesmith is offline
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Quote:
Originally Posted by LouieAtienza View Post
If I were you, I'd sell that expensive heat blanket, buy some heat bulbs and more resin. You have 8 guitars to build. Don't renege on your promise.

Really, with 10000€ I could have bought a CNC, all the resin, CF, wood, and hardware, and still had enough left over to pay myself. I'd do whatever possible to salvage that mold, fix it, Bondo it, whatever. Get it done.

And, there seems to be people here with a lot of CF experience. Eating some humble pie and asking for advice is part of the process.
This resin needs to be room temperature for 48 hours and then become 70 degrees celcius for 15 hours. Can a bulb become so hot that the mold will become 70 degrees?

This 10k was for everything. I had no specialised luthier tool what so ever. This loan had random orbital sander, buffing machine, router, luthier tools like radius sanding beam, straight edge. then there was more then 1000 euro in shipping and import tax. I had to make everything work with this ammount + the ammount must make a number of units that can repay the full ammount so i chose 8 units (now you have 8x materials cost, aero resin, carbon, fiberglass,hardware,wood), then the prices would be fair.
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  #27  
Old 05-26-2016, 12:48 PM
littlesmith littlesmith is offline
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Quote:
Originally Posted by PeterF View Post
I feel your pain! I've had big layups go completely wrong on me as well.
I think your problem is the heat. I think I've said before that there is no need to heat cure epoxy at all, unless you're using it in critical, high strength applications. A mold is not one of them! A guitar body isn't even one of them. If I were you, I would forget the 'aerospace grade' stuff and just get some normal epoxy from a normal fibreglass supplier. It will make zero difference to the end product - a guitar is not an airplane!
Also, having voids and bubbles in they mold layup is not a deal breaker. As long as the gelcoat surface is smooth, you're good to go. Again, the mold is not a structural part, so it doesn't need to be treated like one.
I really hope you keep going with this. I'm sure you will be able to make good guitars once you get all the problems ironed out.
The layers of gelcoat did not bond to eachother, making them individual layers, completely seperated. The entire thing broke into 100s of pieces when i was starting the procedure to seperate the negative from the plug. I mput on 3 layers of gelcoat in 1 session, but with time in between to let it gel up a bit, i was afraid of putting a thick layer for the heat generation. The fiberglass was also not bonded on the last layer of gelcoat. The whole mold must be 1 solid mass.

Im gonna skip the heat on this next mold with the left overs (about 1/3 of what i used oon the other one) now and just make it quickly. I wil make a mold now thats only the body area, then i will make a wooden structure with the seal channel for the reusable vacuumbag. I hoped to get 1 nice mold with a continues gelcoat surface, but this huge thing would not release at all (a cnc machine design would have 89 degree angles instead of 90 on the seal flanges to help with release). I`ll build a wooden board on top of the composite body mold with all the extra stuff, assuming it will work this time. I`m gonna mix all the leftovers in 1 time, which is about 2 kg gelcoat, 10 square meter fiberglass, and about 3 kilo epoxy. In a perfect scenario, this would be enough for a body only mold.
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  #28  
Old 05-26-2016, 03:41 PM
LouieAtienza LouieAtienza is offline
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Quote:
Originally Posted by littlesmith View Post
This resin needs to be room temperature for 48 hours and then become 70 degrees celcius for 15 hours. Can a bulb become so hot that the mold will become 70 degrees?

This 10k was for everything. I had no specialised luthier tool what so ever. This loan had random orbital sander, buffing machine, router, luthier tools like radius sanding beam, straight edge. then there was more then 1000 euro in shipping and import tax. I had to make everything work with this ammount + the ammount must make a number of units that can repay the full ammount so i chose 8 units (now you have 8x materials cost, aero resin, carbon, fiberglass,hardware,wood), then the prices would be fair.
Even beyond 70degC.

There are a lot of tools you could have made yourself! You have a router, making a radius beam is easy. You don't need a buffer, they make foam pads with Velcro you can use on your RO sander. I can add all the tools I ever bought in my woodworking career, including stuff I bought recently and it wouldn't add up to $14000, and that's with a CNC router table I built for under $1500. Heck you could have built half the tools you need with the CNC. Just saying, when you're working with borrowed money you got to think a bit more about how you approach things otherwise it starts costing you. You still have a chance to make good, even if you only build half the guitar's it would be a success.

Glad you're sticking with it, and if you do it will pay in the end.
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  #29  
Old 05-27-2016, 05:06 AM
littlesmith littlesmith is offline
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Originally Posted by LouieAtienza View Post
Even beyond 70degC.

There are a lot of tools you could have made yourself! You have a router, making a radius beam is easy. You don't need a buffer, they make foam pads with Velcro you can use on your RO sander. I can add all the tools I ever bought in my woodworking career, including stuff I bought recently and it wouldn't add up to $14000, and that's with a CNC router table I built for under $1500. Heck you could have built half the tools you need with the CNC. Just saying, when you're working with borrowed money you got to think a bit more about how you approach things otherwise it starts costing you. You still have a chance to make good, even if you only build half the guitar's it would be a success.

Glad you're sticking with it, and if you do it will pay in the end.
This 10k plan was a stripped down 30k plan. 10k is really not alot if you don`t have any tool at all. As i said, 1500 was gone in tax and shipping, etc. etc. I was extremely carefull with every penny, logging every expense in a sheets file. I can say with confidence that i made the best of this ammount and have spent it responsibly. This 10k was budgeted when a company was going to make the bodyes, they were quoted on 150 per body and 3000 for the mold, then they wanted 1500 per body 2 weeks later. At that point i decided to make them myself with the same 10k. These 8 units in raw guitar materials alone is 4000 Euro (not including mold materials), this is not a mahogany acoustic, this is super high tech. 4k on guitar materials, 1.5k on shippng and tax,1k on the mold, 3k on guitar tools and electric machines, 500$ on plywood. This money was gone in an instant and i don`t have half of what i really need. Now i have to go to the 4 people that wanted a guitar and say i can no longer do it for $1000, it doesn`t add up anymore now that i have to pump personal money in it again. If i want to keep one of the 8 units i will build, i have to buy it myself for 1500 Euro...

I do have to say that i am very gratefull that somebody loaned me 10000, this is already very special in this economy.

I caught the mold error early so i was able to only put half of the fiberglass budgeted for the mold on, thats why i have another shot now. I have to ride this out now, the alternative is paying 50 per month for 13,3 years. The composite body is the cornerstone of this entire project, i have everything i need except a mold, i need to get over this hurdle one way or another. At this point the financial damage is $500 in this mold, the other stuff is fine. If the second mold attempt fails i have a very unconventional alternative. Laying the composites on the waxed plug in a vacuumbag. This would make the nice and shiny side on the inside of the guitar body, not the outside where you want it, and every body would have to be flattened on the outside and sanded and clearcoated. Thats extremely labour intensive, and its not a negative mold, so its the exact opposite of the correct method. But if thats the only way to get to the finish line, i will do it. This would mean the neck is 2 millimeter wider on each side and the body as well.
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Last edited by littlesmith; 05-27-2016 at 05:34 AM.
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  #30  
Old 05-27-2016, 07:12 AM
LouieAtienza LouieAtienza is offline
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Originally Posted by littlesmith View Post
This 10k plan was a stripped down 30k plan. 10k is really not alot if you don`t have any tool at all. As i said, 1500 was gone in tax and shipping, etc. etc. I was extremely carefull with every penny, logging every expense in a sheets file. I can say with confidence that i made the best of this ammount and have spent it responsibly. This 10k was budgeted when a company was going to make the bodyes, they were quoted on 150 per body and 3000 for the mold, then they wanted 1500 per body 2 weeks later. At that point i decided to make them myself with the same 10k. These 8 units in raw guitar materials alone is 4000 Euro (not including mold materials), this is not a mahogany acoustic, this is super high tech. 4k on guitar materials, 1.5k on shippng and tax,1k on the mold, 3k on guitar tools and electric machines, 500$ on plywood. This money was gone in an instant and i don`t have half of what i really need. Now i have to go to the 4 people that wanted a guitar and say i can no longer do it for $1000, it doesn`t add up anymore now that i have to pump personal money in it again. If i want to keep one of the 8 units i will build, i have to buy it myself for 1500 Euro...

I do have to say that i am very gratefull that somebody loaned me 10000, this is already very special in this economy.

I caught the mold error early so i was able to only put half of the fiberglass budgeted for the mold on, thats why i have another shot now. I have to ride this out now, the alternative is paying 50 per month for 13,3 years. The composite body is the cornerstone of this entire project, i have everything i need except a mold, i need to get over this hurdle one way or another. At this point the financial damage is $500 in this mold, the other stuff is fine. If the second mold attempt fails i have a very unconventional alternative. Laying the composites on the waxed plug in a vacuumbag. This would make the nice and shiny side on the inside of the guitar body, not the outside where you want it, and every body would have to be flattened on the outside and sanded and clearcoated. Thats extremely labour intensive, and its not a negative mold, so its the exact opposite of the correct method. But if thats the only way to get to the finish line, i will do it. This would mean the neck is 2 millimeter wider on each side and the body as well.
Just making suggestions where you can sell some of the more expensive stuff you could do without, which should free up some money to get what you really need.

I don't know how happy your customers would be with a neck that's 4mm wider, unless you were making a classical.
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