ChuckT

Very nice Wolfe! Great use of an already available part.

Looks great Wolfe. Did you fabricate the plug attachments or do they come with those wires?

That does help. Thanks for the description.

Lookin good Wolfe! On those valve stems, I take it your cutting them down at the top, is that right? How did you end up attaching them at the bottom? I have the same items to use on my W.4 build and would appreciate any tips you can offer.

Thanks guys for the encouragement.

I have the data file and a good amount of info on the D.II, so I think I should be good. Thanks for the heads up though, Chuck.

SUCCESS! I did a test run last night using what everyone suggested and it came out perfect! Zero bubbles on the surface and inside and a glass smooth surface capturing everything! Exactly what I was hoping for. Now I just to wait for more silicone. Thanks again everyone, Chuck.

Thanks everyone for the feedback. I am set up to do vacuum degassing and pressure casting, so I do hope to resin copy this master for myself and then anyone else if it meets there standards and they are interested. I did a little more last night. first, I fixed the angles on the bottom so they match (still needs a little tidying up) then worked on some details the cap still needs a handle added to the center and in this pic I didnt center everything in the hole. I just wanted to see how it will look

I'm not sure if this is the right forum for this or not (being that its a conversion of the Roden 1/32 Albatros D.II to W.4 sea plane) but hey, its from the Great war so I figured, why not! I plan on converting Rodens 1/32 Albtros D.II to W.4 sea plane. That will require new wings, flying surfaces, struts and floats along with various other little details. I have scratch built a W.4 float that I hope to detail, then resin cast for use in my conversion of the Roden kit. I have the basic shape of the float done and am working on making the other details needed to add to bring it all to completion to then cast. What I'm looking for is honest feedback on the look and shape of the float. I can already see I need to fix the angle on the bottom (as it isn't even) but is there anything else I'm missing? Feel free to be honest. Thanks in advance, Chuck.

Thanks Tim for the info. When I pull a vacuum it takes roughly 1-2 minutes to get the gauge on the pump to read 29"/HG. At the pots gauge it reads 28"/HG. If I keep the pump going I can get it down to just below 30" at the pump which gives me roughly 28.5" at the tank. This is where I shut off the pump and let it sit for the required times under a vacuum. Should I keep the vacuum pump going the entire time the silicone is in the pot or will those burn out the pump? What do you suggest?

I think I found a reference photo that shows the fitting you represented with the hex rod. I haven't seen that detail before! Nice work Wolfe!

No worries Wolfe. I zoomed into the pic and I think I get what it looks like. I haven't noticed that hex fastner detail before when looking at engine pics. I'm wondering where you found this detail? Have you seen the detail shots from Jamo for the D.IIIa? I can post a link if you haven't.

Never though about keeping the silicone on the cool side, that makes sense to slow down the reaction! I'll give it a try using my modified method and your suggestions. Stand by for updates.

For those of you wondering how my first attempt at silicone mold making (using a vacuum degassing set up) went, it didn't go as well as I hoped. Here is what I did: -mixed two part silicone for a full three minutes (careful to scrape the sides and bottom of mixing container) to get as complete a mix as possible -poured silicone into mold box slowly, using thin stream away from master (letting it build up around master) -vibrated mold box to encourage complete coverage for one minute -put mold into vacuum pot and brought vacuum to 29"/HG (took about a minute to fully degass vacuum pot) and turned off pump -held it at 29"/HG vacuum for full three mintues, then slowly let pressure return -pulled vacuum again and this time let it sit under a vacuum for several hours The pot held its vacuum for the several hours but it did slowly loose it over time. I don't think I had the lid on as tightly as I should have. After five hours of letting it sit, here is what I found: I noticed right away that the level of the silicone on the sides of my mold box indicated it had only risen maybe 2 to 2.5 times it's original height. I also noticed there were some medium sized bubbles (about 2mm across face) on the surface of the mold which surprised me and indicates to me that I needed to get it under vacuum sooner, for longer. I removed the mold from its box and inspected it further. I noticed the detail of the master it captured was really no better than when I have made molds without degassing. After breaking open the mold I also saw that there are medium and smaller bubbles trapped within the silicone! Kind of bummed at that. So my main problem is still bubble entrapement. I am going to forget about the vibrating part, put it under vacuum right away after mixing for three minutes and then hold that vacuum for a full seven minutes as some have suggested. I'll do all this is a larger container to allow for expansion. After that I will break the vacuum, pour it into my mold box, vibrate one minute and put the mold back in the pot and pull it under vacuum to leave for 5 hours. What do you guys think? One thing I noticed when pulling a vacuum is the guage on the pump would get down to 29" but the pot would show roughly 28". The pots guage is a cheaper vacuum guage so I'm not sure how accurate it is, but could there be that much difference in vacuum between the pump and the pot? Last but not least, should I keep the pump on the entire time I am pulling my vacuum that first time (seven minutes) or turn it off once it gets down to 29"? Thanks again guys, Chuck.

Got it. My first degassing/molding attempt went well and I am just leaving it to cure over night. I'll let you all know of the results in the morning when I take a look.

Fantastic! All this info is sure helping paint a clear picture for me. I'm now off to give a go at vacuum degassing. Wish me luck, Chuck.

I do have the ability to Vacuum degass (the silicone) AND pressure cast (the resin) so I plan on doing that. Thanks again, Chuck.

Cool! The results speak for themself.

I hold the end of our household vacuum hose just over the surface of the silicone and it sucks all the air out to give me a vacuum, right (kidding of course!) I have a vacuum pump and and a modified pressure pot that allows me to pull down to 29"/hg. I like your castings, looks good. Thanks for the info, Chuck.

Thanks Hubert. It's my undstanding that if I do not degass the silicon under vacuum, when I go and use pressure for my resin casting, it will cause the trapped bubbles in the silicone mold to collapse and distort my mold. Does that sound right to you? I have also read that if you are NOT going to use pressure for casting your resin you do not need to use vacuum to get the bubbles out of your silicone. Its starting to make sense to me now. I like your idea of brushing on the initial coat of silicone though. Thanks for the input, Chuck.

Hey Wolfe, any chance of getting a close up pic of your clamps with the Hex fastner? Looks great!

I am about to make some silicone molds and I'm unsure if after degassing the silicone (to get out the air bubbles) if I need to let the silicone set under pressure? If I understand the process correctly, I mix the silicone, put it in a large container (to allow for expansion) and put it under a vacuum to degass the silicone. Once the bubbles are out, I pour the silicone over my master (in a box) and let it set up. It's here where I'm unsure of the process. Do I let the silicone set up at atmospheric pressure or in a pressure pot at say 40 psi? I know I am to cast the resin under pressure, but not sure about the silicone mold itself? Thanks in advance, Chuck.

Thanks for the confirmation.

Hey Wolfe. Just enjoying re reading what you've posted and saw that you covered the instrument faces with punched out clear sheet. What type and thickness of material did you use to represent this clear glass? Looking forward to you next posts, Chuck.

Thanks for the info. I do have this data file and I am planning on making the larger wings and tail plane. I have the floats completed (minus some of the finer details) but was hoping to get started on the inetrior. I don't have anything on the D.I's interior but do the D.V. Do you think it would be close to it?