Vacuum press.

[Celt40]

Could i use a Vacuum Veneering Press to cast???? Or can i hear you all laughing at this post.[:I]

 

[Darley]

Could i use a Vacuum Veneering Press to cast???? Or can i hear you all laughing at this post.[:I]

I don't think it will work as Vacuum Veneering Press is vacuum by hand or I might be wrong

 

[Fred]

I would remark that I believe a vacuum is a vacuum no matter how it is obtained. However, the veneer presses I have seen in operation would, to me anyways, be awkward to get set-up and use. I highly recommend the Harbor Freight pressure pot. Check with them and see if it is currently on sale. You may also want to call your local store and double check. It should be around $40 I believe.

Using the pot will be far easier on you and should take up less room in your work area. I use a three gallon plastic container that once held ice cream and put my jar with chemicals inside it and then into the pot, seal it up and pull the vacuum. This protects the pot from any boil overs or spills that may occur. The handle also helps in removing the work.

BTW, the ice cream is always good too!

 

[Celt40]

The problem i have is that over here in the UK we don't have HF. The company i get my resin from will be setting up a section for vacuum casting, but say it will be limited stock???

You members that live in USA are lucky and spoiled for choice. Over here we are not so lucky with choice.

 

[Fred]

If you already have a vacuum pump - or can get one- you can use a large glass pickle jar with a fitting soldered into the metal top. I used one for my first setup and had great success. Remember though that if the bottle is glass then you are subject to breaking it and making quite a mess of things and potentially getting hurt from all the flying glass.

I never pulled more than 15" of vacuum and achieved some very acceptable stabilized woods. I was using a solution of Methyl Ethyl Keytone (MEK) ans clean white styrofoam. Pre-drill your blanks under size and preturn down a good bit and the wood will take up the solution through and through. Then re-drill and mount the brass tubes and finish turning.

Be VERY careful when using MEK as it is deadly and can really mess up your soft body tissues. It is the only solvent that I found that would dissolve the styrofoam and not make a thick mess. It should be available to you in ant good automotive paint shop.

Oh yea, the glass jar is great as you can see how fast thinks begin to boil and then you can switch on an off the vacuum pump. Just don't let the NMEK get into the vacuum line as it will ruin the pump for good.

Good luck and let us know how you get on with your efforts. :biggrin:

 

[Modelmaker]

if you want a "professional" setup go get a 12" or 14" pvc pipe connector, drill and tap a hole in the side for your vacuum line/valve/pressure gauge setup. get 2 pcs of 3/4" thick acrylic and some rubber sheet. cut the rubber into two gaskets that match the pipe connector. to assemble place one piece of the acrylic on the table, place on one of the gaskets, place your pipe connector. put your silicone (or whatever you want to vacuum into the chamber, place theother gasket on top and place the last piece of acrylic on top of that, apply vacuum and you're finished. with the acrylic you can see the de-gassing of the silicone and watch for overflow.
the vacuum will basically hold everything together.
I'll try and post pics of my set-up later

 

[cozee]

I use both 1 quart canning jars and 1 gallon pickle jars. Pulled both to 31" on numerous occasions without any implosions. Pre-drilling blanks with a 1/4" bit helps to speed the process. There are also heavy vinyl bags available for vacuum processes also.

 

[BigRob777]

I own a press that's somewhere between a pro and hobbyist leve. I tried my first veneering job, with yellow glue, but I put way too much in and it squeezed out all over the bag. I'm afraid that might happen to you and you might have trouble cleaning it up. Then again, if it doesn't stick to the bag, it might not be so bad. Mine goes up over 1,500 psf I think (Designed to pull 25.5" of Hg [at sea level]). I'm not sure if that's more than a pressure pot does, but I imagine it is. You can test it, by putting a drop on the outside of the bag, on a corner that doesn't matter and see if it comes off easily. If it doesn't, by all means, don't try it inside the bag, or you'll probably end up having to buy a new one. Also make sure that your container is well rounded, with no sharp corners, or edges. I'm no expert, but I hope this opinion helps.

Another idea is to post the question in the vacupress forum, hosted by Darryl Keil. I'm there with the same name. Those folks have much more experience than I do.

Rob