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(Unregistered Guest)
Unregistered guest
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, January 09, 2006 - 08:05 am: | 
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I'm creating a mold to create my own amphibious body design and I would like to know the thickness of the upper and lower bodies of maxes, argos, etc.
thanks,
andrew |
david berger
Senior Member
Username: Davidrrrd
Post Number: 234
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, January 09, 2006 - 09:42 am: |
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about 1/4"
you want strenth but you dont want too much weight.
how will you use this mold?
will you form polyethilin sheet into a body? or are you thinking about fiberglass?? |
Andrew Lapp
New member
Username: Andy
Post Number: 2
Registered: 02-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, January 09, 2006 - 11:21 am: |
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david,
i will vacuum form it using hdpe sheets. my friend and i already made the upper body plug, ready to try and make a mold. we thought of fiberglass, but wanted something lighter but as durable.
i remember reading something on the thread a while back about a thickness of .187". i know it was on the max. maybe it was the upper body?
thanks,
andrew |
david berger
Senior Member
Username: Davidrrrd
Post Number: 236
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, January 09, 2006 - 05:21 pm: |
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this is why i asked, in vacume forming you start with one thickness but depending on shape your forming, the beginning sheet thickness and where you place just how much heat you can get diferent thickneses, the trick of coarse is to kepp as much or at least as even as posable, specaily in corners and deep spots, you must still have enoph there for the strenth and integrity, but you already knew this, in body tops there might be a spot you will cut out laiter anyway that extra heat might alow to get thinner so other parts stay thick, but this is pushing the envelope . . so to speek.
the bottom can be aproched from multiple ways but heres one or two,
use thich enoph sheets for bottom so the deep corners are strong, also vairy heats to sacrifice from eraeas that dont get streched normaly to leave some in the over streched points, (you might even cool these spots slightly)next idea is a third mold for cloase fitting full skid plate/secondary exterior lower 1/3 hull, make it standered equipment and snug enoph to seal with rubberized caulk or similer product and marine pop rivets + the axel bearing points will also secure it.
this third mold is 1/3 deep and will not strech your sheet much, thus leaving it verry verry strong. |
Andrew Lapp
New member
Username: Andy
Post Number: 3
Registered: 02-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, January 09, 2006 - 05:25 pm: |
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david,
thanks for all the info. did you ever vacuum mold hdpe or abs before? how did you heat the plastic?
thanks,
andrew |
david berger
Senior Member
Username: Davidrrrd
Post Number: 237
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, January 09, 2006 - 06:21 pm: |
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yes some of the machines i used at incase molding co. (17.5 years)
you must build your mold as part of a machine, say as a station that can be exchainged with other molds in an ovan that heats the sheet, maybe as simple (if you find it works)as a dome over the sheet while the sheet is fixed along the sides to your mold,
the dome can be 4 or 5 inches or more from the sheet and still work fine, and alow cloas inspection of sheet by eye.
inside the dome ther needs to be heat soarces, heat elements or maybe gas flames or something, the machines i have used had glass rods with heater elements in them, prehaps you can canabilize an old electric dryer or stove or two for the elements and heater controls, you place the elements where you need to controle heat and adjust the controls from element to element to prefect your moding prosses,your dome should be moveable so you can precisly controle heating time, like whaiting till the sheet begins to droop a certin amount in the center you can lift the hood away and begin the vac prosses, of coars theres the trial and error to be expected.
when you find a good prosess write down positions of heater controls as next mold in your machile will need diferent positions. |
Andrew Lapp
New member
Username: Andy
Post Number: 4
Registered: 02-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, January 09, 2006 - 07:10 pm: |
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david,
is it okay for the polyethyne to bow down a lot in the middle? are there any keys to knowing when the plastic is perfectly soft to form rather than heating it to much and becoming too thin? so is the dome to help concentrate the heat in a certain area? so if the mold is part of the station, what materials should it be made of? thank you so much for all your input. you're the first person i talked to who has been of help.
thanks,
andrew |
david berger
Senior Member
Username: Davidrrrd
Post Number: 238
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, January 10, 2006 - 09:40 am: |
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to knowing when the plastic is perfectly soft to form rather than heating it to much and becoming too thin? ** TRIAL AND ERROR**is the dome to help concentrate the heat in a certain area? *** YES A SHEET METAL FABED DOME THINGY WITH YOUR HEATER ELEMENTS INSIDE IT WILL ACT AS AN OVEN**so if the mold is part of the station, what materials should it be made of? , WHAT WERE YOU GOING TO USE FOR YOUR MOLD? JUST MAKE EACH MOLD WITH LEGS OR WHEELS AT SAY WAST HIGH SO THE SHALOW AND DEEP MOLDS ARE SAME HIGHT AND CAN BE PLACED WHERE REST OF OVAN IS, NEXT A WINCH OR SOMETHING TO LOWERE AND RAISE YOUR OVEN,MAYBE SOME SORT OF RODS FROM ROOF TO GUIDE THE OVEN SO IT STAYS ALIGNED WITH THE MOLDS, BUT MOLDS ARE INTERCHAINGABLE, WHAT WERE YOU PLANNING TO USE FOR YOUR VACUME SORCE, ID SAY START WITH 2 BIG WETT VACKS ONE AT EACH END OF MOLD BUT BOXED IN UNDERSIDE OF MOLD FOR THE VACUME MUST BE PORTED THREW YOUR MOLD IN PREHAPS AS MANY AS HUNDREDS OF PLACES IN ORDER TO DRAW THE PLASTIC INTO ALL THE CREVISES OF YOUR MOLD AND QUICKLY AT THAT! THE SMALLER THE HOLES DRILLED THE MORE YOU WILL NEED OF THEM. BUT YOU KNEW THIS, MIKE ABBEY MAY ALSO HAVE USEFULL INFO IN THIS ENDEVOR,
SO WHATS THIS BUGGY GOING TO LOOK LIKE, WHAT SORT OF TRANS, CAN YOU HINT AT ALL ABOUT THE TECH YOU WILL ATEMPT TO INCORPEREATE INTO IT? |
liflod
Intermediate Member
Username: Liflod
Post Number: 66
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, January 10, 2006 - 10:17 am: |
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I would recommend a trip to Ontario and tour the Argo factory. They recently purchased a new vacuum forming machine. It heats the sheet to around 600 degrees and then places it on the mold and vacuum pulls it down to form it in the mold. I believe they use 3/8 inch HDPE sheets.
If I were to try something like that, I would use forced hot air for heating. You will need to have some form of vacuum system to get the plastic to from to the mold. Maybe even have the molds heated too. The factory operation takes just few minutes. I don't think a home built system will be that fast, so you will need to keep the plastic hot enough once it leaves the "oven".
There are web sites out there devoted to vacuum forming. |
Andrew Lapp
New member
Username: Andy
Post Number: 5
Registered: 02-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, January 10, 2006 - 02:50 pm: |
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david and liflod,
thanks for all your help. all this info gives me a lot to think about and gives me some new ideas as well.
david, to answer your question, my friend and i are trying to build a trans somewhere between the T-20 and the attex bakerhill, but you would still be able to steer one side in reverse and the other in forward without shifting. then you can lock it so it only skids as well. the pastor at my church created the steiner and ventrac companies. they make tractors that don't tear up turf, so he has helped me succeed in making my 6x6 so it is turf-friendly. as far as looks, i will post this once i get further into the project. i have the upper plug mold created, but it still is a little too early. it does look like your conventional 6x6 though. are there any ideas that you guys would like to see incoporated into this project as far as design ideas, parts, etc?? i would like this project to suit many people's needs.
thanks,
andrew |
david berger
Senior Member
Username: Davidrrrd
Post Number: 239
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, January 10, 2006 - 05:07 pm: |
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much of the damage i have done to my maxII over the years i have driven it center in the chain tentioner area,
i have blown a number of chain tentioners apart, i have had mixed results building my own.
now my friams twisted,bowed and broken and in each case directly in the chain tentioner area, this force i beleave can be countered with an ideler/tentioner system that shifts with the tention as you go from power to brake, ect..ect..
and yet still take up enoph slack to asur chains remain in corect contact with sprokets,
i have sean some racers with little roller or nylon pads on each side of sprokets to ashure chains are guided on in each direction, this is an idea i was concidering myself, however im thinking a set of sprokests or rollers could be tied together and adjustable for the slack adjustment while at same time free to shift as tention go's from top chain to the bottom , as slack side comes under tention it draws the ideler set up and taks up slack as tentioned side gos slack! this should prevent fraim from geting the brunt of the force, frams arnt shock absorbers, my idea is to prevent the shock and also prevent fraim and adgusters from becomeing the fulcrom of the shock,
you can take the palm of your hand down from your forhead now, LOL |
Emil Kushner
New member
Username: Kushwa
Post Number: 3
Registered: 03-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, January 10, 2006 - 07:25 pm: |
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info on vacuum forming
http://www.fxsupply.com/vacuum/vacuum.html |
Richard Clark
Moderator
Username: Richard
Post Number: 12
Registered: 02-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, January 11, 2006 - 07:55 am: |
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6x6 Friends
On a side note in reference to MAX II poor chain adjusters, We have good set of updated chain adjusters available at good prices, see link below:
http://members.aye.net/%7Erclark/parts_chassis.shtml
Thanks
Richard Clark
ROUTE6x6
RICHARD'S RELICS
812-944-1643 8am-6pm EST weekdays |
david berger
Senior Member
Username: Davidrrrd
Post Number: 240
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, January 11, 2006 - 08:35 am: |
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thanks richard, im probly going to use the rollers on my back chains, my own sprokets servived well enoph in frount, the fraim in the frount was bending and i will need to strenthen next fraim there, however the forces in the rear were more extreem, my next fraim must be strenthend conciderably in the rear due to stresses on the chain adgusters mounting point.
my sugestions in this new on the drawing bord vehicle is to avoid transfering the force to fraim, insted canceling it out with equel and oposet conditions, (if in fact it is posable)
some sort of pivoting double roller thingy might also work with a roller above top chain and below botom chain, tence chain pushes on loose chain, and when they chainge rollers automaticly transfer the condition to oposet chain, idea is yet to be engeniered threw,it is a challenge! |
Howard Hoover
New member
Username: Howard_hoover
Post Number: 6
Registered: 10-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 12, 2006 - 12:28 am: |
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I have been working on my own AATV project for a while and was planning on making my body out of HDPE. There is a guy in TN. that I talked to about it and he said you can make your mould out of hardwood like poplar or foam whatever you are going to make it out of. Then he would make a fiberglass copy from it to use in the vacuum forming process. If you just used your wood mould for the process it probably wouldn't last very long as the heat & humidity would warp it etc. You then keep your mould at home as it is now worth it's weight in gold to you and if you need to make any changes to it you can, and then another fiberglass copy can be made for the changes or possibly just be changed without having to make another complete copy as fiberglass can be cut out & reworked.
There is some very good information at this site www.dc-rc.org/vacnotes.htm
and this other link shows an animated process being done probably similar to what you will be doing. www.thermo-fab.com/vacuum_forming.shtml
I am really interested in the transmission you talked about since I am getting ready to have a
one off custom built differential made for a cost of at least 1500.00 just for the Differential!
can you say how much it would cost to get a trans built like the one you are talking about? and would it stand up to the torque & HP of a 60-75 HP VW engine? Thanks Howard |
Howard Hoover
New member
Username: Howard_hoover
Post Number: 7
Registered: 10-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 12, 2006 - 12:59 am: |
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You might get a couple of wet vacs to work but it would probably be very slow. The way the Vacuum
works in a Vacuum Forming Machine is: they will have a Tank say 300-400 gallons some smaller maybe some larger. The air is SUCKED OUT of the tank to a negative pressure & then when your ready to form your HDPE a valve is opened and air RUSHES BACK IN the tank forming your body in the process in just a few seconds depending on the size of the tank of course. Some larger operations may have a tank with a dividing wall in it so you don't have to wait on the air to be pushed back out of the tank to form a second body. While one side is forming the other side is pushing air out getting ready for the forming process. Or they may use two smaller tanks. and get by with only compressor. Howard |
Andrew Lapp
New member
Username: Andy
Post Number: 6
Registered: 02-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 12, 2006 - 06:58 am: |
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Howard,
thanks for the info. i was planning on sucking air out of a tank, but i may be in need of a larger tank (i was going to do about 60 gal. or so). both of the website were VERY helpful. as far as the transmission, it will be built to handle about 100 hp or so. my friend and i will be using a 60 some hp suzuki katona engine for our racer (which just so happens to be the first thing we build) lol. I will keep you guys updated on the trans once i get further with it. it's still in the early planning stage.
thanks again,
andrew |
david berger
Senior Member
Username: Davidrrrd
Post Number: 243
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 12, 2006 - 09:50 am: |
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the first site in this thred sugested a 2 stage aproch, 1st is the vacume motors and second is the tank method, i think this is still a wise aproch, you can stick to the wood mold, just keep your first body for fiberglass copy if you need em laiter, you will likely be molding em one at a time, here and there, i don't think you will nead a heavy production sceduale so the wood will servive a while, you dont want some extreemly suden vacume pulss drawing the sheet into your mold anyway, it would just tear the sheet, the vacume motors should be able to draw at speed the sheet will like to strech, lets not forget just how big this heated plastic sheets serfice is,
you wand it to strech and seak to fill voids, if you blast it into mold like it was hit by a car it will probly pop the heated film.
the ovan may even remain as thesheet is drawn,
trail and error, |
Howard Hoover
New member
Username: Howard_hoover
Post Number: 8
Registered: 10-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 12, 2006 - 11:43 am: |
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I have seen Vacuum Forming done before it is heated to the point where it starts to stretch (sag)then lowered, or the mould raised up
into the sheet. At this point the sheet is already so hot & flimsy if it weren't for the clamps holding it in place it would droop down around a lot of it. As far as that goes I don't know why they don't release it from the clamps once it is lowered onto the piece anyway because it seems to me that if it is not released then it will be stretched that much farther making your body or sheet even that much thinner! so unless your using too thin of a guage already or your corners or angles are too tight. I seriously doubt that a vacuum forming process from a big tank would just pop or tear your sheet I'm not saying that it can't happen but unlikely. |
david berger
Senior Member
Username: Davidrrrd
Post Number: 244
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 12, 2006 - 02:16 pm: |
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could also depend on distribution of the heat |
Andrew Lapp
New member
Username: Andy
Post Number: 7
Registered: 02-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 12, 2006 - 02:54 pm: |
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i could see how the plastic would be stretched a little, but if you start out with a fairly wide piece of plastic i don't think it would become much thinner. |
david berger
Senior Member
Username: Davidrrrd
Post Number: 245
Registered: 01-2005
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, January 12, 2006 - 03:17 pm: |
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probly not for uper body, engine cover,floorboards,even skid plate idea, but lower body may be 3 feet deep for all we know, and detail in the design may be there for upper body suport and ridgitity, ect..ect.., thats the true test |
Andrew Lapp
New member
Username: Andy
Post Number: 9
Registered: 02-2005
Posted From: 68.56.11.131
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, February 06, 2006 - 06:35 pm: |
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I finally acquired a nice and very powerful vacuum pump for free from my neighbor. so the next thing is to build a dome to heat plastic. |
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