View previous topic :: View next topic |
Author |
Message |
jonmiller Newbie
Joined: 05 May 2011 Posts: 10
|
Posted: Thu May 05, 2011 2:30 pm Post subject: vacuum cleaner vs vacuum pump |
|
|
Hi everyone
Firstly, looks like a great site with lots of info.
I am a custom painter specialising in radio control bodyshells. I have my own line of paints etc and want to make some micro bodyshells in order to save money. They will be used for showing new colors/paint effects I bring out etc.
Anyway, onto my main question.. I have seen various online videos of home vacuum forming and would like to have a go at it. I will be forming using lexan, maximum thickness 1mm.
I have seen various setups, some using vacuum cleaners and some using vacuum pumps with tanks.. Is the purpose of the tanks to create more pressure in order to form thicker materials? If so, I assume I will be ok just using a vacuum cleaner in my setup due to the thickness of the material I will be using correct?
I look forward to getting familiar with the basics and a basic starting setup like the ones on online videos and hopefully in future creating a much more sophisticated setup like some of them in the gallery.
Congrats to everyone who has posted there, some very nice work
Many thanks,
Jon
|
|
Back to top |
|
|
spektr Master
Joined: 07 Jan 2008 Posts: 425
|
Posted: Fri May 06, 2011 9:43 am Post subject: |
|
|
use a low cost vacuum pump and a 5 gallon tank. the tank doesn't increase pressure, it adds volume. a vac pump doesn't move enough volume fast enough in most cases to make good parts. A vacuum cleaner will probably do it, but why not do it in a more conventional manner and have the ability to pull many different materials. |
|
Back to top |
|
|
jonmiller Newbie
Joined: 05 May 2011 Posts: 10
|
Posted: Fri May 06, 2011 11:33 am Post subject: |
|
|
Hi, thanks for replying. Pumps are quite expensive from what I have seen plus you need to get a tank so being able to use a vacuum cleaner to sart with would be ideal as I already have one.
I just want to get started and get a grasp of making molds and the basics of vac forming. I will only be using maximum of 1mm polycarbonate. By the time it comes to need a more competent former I would hope to have the knowledge to buil a better more permanent one.
Seeing as my main work is airbrushing I do have a couple of compressors, a smaller one with a 25litre tank then a larger one with a 150litre tank. Can air compressors be used/converted to fit the purpose of a vac former.
Sorry for my lack of knowledge on the subject but as said, this is all completely new to me.
Many thanks
Jon |
|
Back to top |
|
|
Fredo Master
Joined: 21 Mar 2007 Posts: 251 Location: Kingdom of Nye Area 51
|
Posted: Fri May 06, 2011 2:27 pm Post subject: |
|
|
This may not be the best way to pull a vacuum but it works in a pinch, http://www.harborfreight.com/air-vacuum-pump-with-r134a-and-r12-connectors-96677.html The connectors would need changing, plus a 5 gal. tank and some plumbing, that and a even heating oven. Then you'll need decent frames to hold the plastic and a platen that doesn't leak..... If you build with the intention to upgrade down the road. You can start out with a vacuum cleaner and change to a hivac pump if you're not happy with it.
Polycarbonate cools really fast, at least that's what I've heard, so you have only a few seconds to form it. I'm not sure what the minimum vacuum former is that will do the job, but I'm betting it's not worth the money you'll spend trying to find out............Fredo _________________ If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001 |
|
Back to top |
|
|
jdougn Guru
Joined: 18 Mar 2009 Posts: 714 Location: Louisville KY area
|
Posted: Fri May 06, 2011 4:10 pm Post subject: |
|
|
jonmiller wrote: | Hi, thanks for replying. Pumps are quite expensive from what I have seen plus you need to get a tank so being able to use a vacuum cleaner to sart with would be ideal as I already have one.
I just want to get started and get a grasp of making molds and the basics of vac forming. I will only be using maximum of 1mm polycarbonate. By the time it comes to need a more competent former I would hope to have the knowledge to buil a better more permanent one.
Seeing as my main work is airbrushing I do have a couple of compressors, a smaller one with a 25litre tank then a larger one with a 150litre tank. Can air compressors be used/converted to fit the purpose of a vac former.
Sorry for my lack of knowledge on the subject but as said, this is all completely new to me.
Many thanks
Jon |
Hello Jon & welcome to the forum. A compressor will not work to pull vacuum. My understanding is that the internal check valves on a compressor will not work to hold vacuum. Try with your vacuum cleaner first & see if it works.
hth, DougN _________________ DougN - Just in case you're wondering, I got my "rating" legitimately... by posting aimless drivel, useless advice, and pointless questions. |
|
Back to top |
|
|
jonmiller Newbie
Joined: 05 May 2011 Posts: 10
|
Posted: Sat May 07, 2011 2:45 am Post subject: |
|
|
Hi Jdougn
Thanks for the response and the welcome. I am hoping it will do for the time being. Will let you know how I get on. Got some lexan and am just waiting for some materials to make a mold. Need to go have a search on the forum for easy and cheap release agents.
Many thanks,
Jon |
|
Back to top |
|
|
jdougn Guru
Joined: 18 Mar 2009 Posts: 714 Location: Louisville KY area
|
Posted: Sat May 07, 2011 6:36 am Post subject: |
|
|
What will the release agent be used for? Molds for vacuum forming can be made of fine grained wood such as balsa or mahogany if needed. _________________ DougN - Just in case you're wondering, I got my "rating" legitimately... by posting aimless drivel, useless advice, and pointless questions. |
|
Back to top |
|
|
jonmiller Newbie
Joined: 05 May 2011 Posts: 10
|
Posted: Sat May 07, 2011 11:41 am Post subject: |
|
|
I am going to be using lexan bodyshells that are already available as a base to pour my mold material into (probably a hard sculpting plaster) and just wanted something to 'grease' up the inside of the shell to make removing the mold easier.
Just had a quick go, found some fiberglass resin I had kicking about and made a little mold using it just for something to test with. Learnt a few things already like the distance the material needs to be from the heater and that it needs heating up slowly to avoid tiny bubbles and surface imperfections in the lexan. It does cool very quickly! I need some struts/supports under my perforated board/platen. Ideally I need to rebuild one better, stronger, (faster?) haha. Preferebly metal.
Just various other basic things.
Although the setup needs improving drastically, it seemed to work ok and so hasn't put me off wanting to continue and make my own shells. Just wish I had access to better work tools and material sources..the DIY stores in my area suck!
Oh well, onwards n upwards..hopefully. |
|
Back to top |
|
|
spektr Master
Joined: 07 Jan 2008 Posts: 425
|
Posted: Sat May 07, 2011 9:00 pm Post subject: |
|
|
i run my rc bodies dry, all lubes do is degrade lexan clarity and chew up the tooling. |
|
Back to top |
|
|
jonmiller Newbie
Joined: 05 May 2011 Posts: 10
|
Posted: Sun May 08, 2011 2:17 am Post subject: |
|
|
Hi Spektr
I did that also when testing forming them, it was just when making the mold from one.
What sort of bodies do you do, just ones for yourself or others too?
I specialize in custom painting them if you ever need it. www.rcsgraphicworx.co.uk
Cheerz,
Jon |
|
Back to top |
|
|
kayaker43 Expert
Joined: 13 Jun 2007 Posts: 175
|
Posted: Sun May 08, 2011 5:25 pm Post subject: |
|
|
Jon
Switch to PETG plastic, its much easier to form with weak vacuum and cheaper. You don't need the durability of Lexan for display models. Release agents are probably not needed if you choose a friendly shape. _________________ Doug Walsh
www.build-stuff.com
Hobby-Vac and Proto-Form machine plans
Also other plans books and videos for people who like to build things |
|
Back to top |
|
|
jonmiller Newbie
Joined: 05 May 2011 Posts: 10
|
Posted: Mon May 09, 2011 1:08 am Post subject: |
|
|
Hi Doug,
Thanks. If I start doing a few shells for others then they have to be in lexan. For small shells for displaying the range of paint colors I sell then perhaps I will look at the PETG option, thanks for that.
I was actually suppries how strong the vacuum created. With the cleaner switched on you couldn't feel much of a draft/suction coming through the pegboard but as soon as the lexan sheet was placed over to create the seal/vacuum it was great. It actually started to weaken the structure and seperated the board from the box. Haha.
Already looking forward to making version 2, this time a bit more study and permanent.
Regards,
Jon |
|
Back to top |
|
|
jdougn Guru
Joined: 18 Mar 2009 Posts: 714 Location: Louisville KY area
|
Posted: Mon May 09, 2011 1:37 pm Post subject: |
|
|
Hey Jon, sounds like the testing worked for you! Post up some picts if you get the chance. Interesting twist on the classic skull & crossbones for your website pict.
DougN _________________ DougN - Just in case you're wondering, I got my "rating" legitimately... by posting aimless drivel, useless advice, and pointless questions. |
|
Back to top |
|
|
jonmiller Newbie
Joined: 05 May 2011 Posts: 10
|
Posted: Mon May 09, 2011 2:18 pm Post subject: |
|
|
too many dougs..best start using usernames
thanks jdougn yes, in a manner of speaking i guess it did. suction can't be too bad if it started to seperate the top and bottom sheets from the frame...or perhaps that was was diy skills coming into play
that will be the first and last time that setup is used. i feel it has provided me with some valuable insight into the sort of setup i need to build and a few helpfull pointers on the mold and material being molded.
more metal/ less wood and more screws. haha. some nice angle steel on the corners too will be nice.
thinking of a similar sort of layout to this. http://www.halloweenfear.com/vacuumformintro.html
get a fairly decent thing built like that and it would allow an easy change of the fixing to change from a vac cleaner to more 'professional' system if the situation called for it.
haven't been able to find any grills like that though but have found these which i can hook up to a basic thermostat and i think will be even better (although very similar) as i can 'snake' them across the 'roof' areaallowing for fuller and more even coverage of heat..i think
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=140514395338&ssPageName=STRK:MEWAX:IT
don't think i will post any pics of the first setup as it seems to be the bog standard starting point of a box with pegboard on it. haha
you'll laugh but i couldn't find any pegboard in the local diy shops so had to make my own..haha. think i need a new drill bit.
sign of dedication though
thanks for the comments on the website too mate. i presume you mean the 'got paint' thing yeh?
many thanks,
jon |
|
Back to top |
|
|
jdougn Guru
Joined: 18 Mar 2009 Posts: 714 Location: Louisville KY area
|
Posted: Thu May 12, 2011 12:26 pm Post subject: |
|
|
Hello Jon,
I think there may be some other user from the UK if your web address indicates your actual location.
Yes, the "Got Paint". The painters mask grabs ones attention.
Notice the "N" after Doug. Makes a distinction between me & Doug Walsh. Doug Walsh (kayaker43) designed the ProtoForm vac former and sells very nice DIY plans for them.
DougN _________________ DougN - Just in case you're wondering, I got my "rating" legitimately... by posting aimless drivel, useless advice, and pointless questions. |
|
Back to top |
|
|
|