Scale Curtiss XP-55 Ascender
- Thread starter Larry B
- Start date
acerc
640cc Uber Pimp
LOL! So true...That sounds good but then I would have to let the shop vac run over night because I use super slow cure epoxy. I don't have to worry about burning up my 500 lb stepping stone weights
Jetpainter
640cc Uber Pimp
Larry some time could you give me a rundown on your glassing process for making the mold, and the fuse itself. Mainly what weight and number of layers of cloth and brand of resin, wax and mold release. Everyone has there favorites, and it's good to hear what works for people.
Thanks, Doug
Thanks, Doug
Larry B
70cc twin V2
I must apologize for failing to finish my "mold making" series! I just got off work tonight and the wife & I are headed down to Mac Hodges field in the morning for an IMAC contest this weekend(we take 2 days).
I promise when we get back I will finish my "how to" series and hopefully give you some good ideas on what works for me. You are correct in stating that if you talk to 10 different modelers about how they make their molds you will get 10 different answers.
I have also been building like a mad man on the Ascender, all the wings are sheeted and the control surfaces are in work. I have not been taking any photo's, sorry about that
Larry B
I promise when we get back I will finish my "how to" series and hopefully give you some good ideas on what works for me. You are correct in stating that if you talk to 10 different modelers about how they make their molds you will get 10 different answers.
I have also been building like a mad man on the Ascender, all the wings are sheeted and the control surfaces are in work. I have not been taking any photo's, sorry about that
Larry B
Jetpainter
640cc Uber Pimp
Have a good weekend!
Bartman
Defender of the Noob!
that's the thing about vacuum bagging, you either pony up the money to do the rig the right way from the start or stick with weights. it seems that the part-time approaches to bagging all have some problem or another that makes them unattractive.
Larry B
70cc twin V2
Hey JetPainter, Sorry in taking so long in posting for you.
Here is a short run down on my mold making methods, once you have the plug in the parting board and the clay has sealed the gap around the edge you are ready for several coats of wax.
Once the wax is done then I spray a coat of PVA mold release and let that dry good. I then spray a nice thick coat of tooling gel coat, I use orange because it contrasts with the black plug color and so you can insure a good thick coat is sprayed. Spraying the tooling gel coat is about like spraying bed liner in a pickup bed if you have ever done that.
I let the gel coat cure to the point that it won't transfer to your finger when you touch it, if you rush this step you run the risk of making the gel coat crinkle up when you start to lay the chopped strand mat over it. It's better to let it sit to long than get in a hurry and screw up you mold!
To make the mold I use the 1.5oz chopped strand matt, and polyester resin. A trick to working with the chopped strand matt is to tear the pieces that you use, this gives you a much better overlap than a cut edge.
As for layers I will use somewhere around 3 or 4 layers of the 1.5oz matt to make the mold, my friend Bob Patton makes his a bit lighter which has it's advantages.
This is it in a nut shell, If you have any questions about something that I forgot or didn't explain well please let me know and I'll see if I can do better.
Here is a short run down on my mold making methods, once you have the plug in the parting board and the clay has sealed the gap around the edge you are ready for several coats of wax.
Once the wax is done then I spray a coat of PVA mold release and let that dry good. I then spray a nice thick coat of tooling gel coat, I use orange because it contrasts with the black plug color and so you can insure a good thick coat is sprayed. Spraying the tooling gel coat is about like spraying bed liner in a pickup bed if you have ever done that.
I let the gel coat cure to the point that it won't transfer to your finger when you touch it, if you rush this step you run the risk of making the gel coat crinkle up when you start to lay the chopped strand mat over it. It's better to let it sit to long than get in a hurry and screw up you mold!
To make the mold I use the 1.5oz chopped strand matt, and polyester resin. A trick to working with the chopped strand matt is to tear the pieces that you use, this gives you a much better overlap than a cut edge.
As for layers I will use somewhere around 3 or 4 layers of the 1.5oz matt to make the mold, my friend Bob Patton makes his a bit lighter which has it's advantages.
This is it in a nut shell, If you have any questions about something that I forgot or didn't explain well please let me know and I'll see if I can do better.
Last edited:
Larry B
70cc twin V2
One ting that I forgot to tell you is that I make my actual parts out of epoxy, not polyester resin. For some reason I got in the habit of using polyester resin for the molds, it is a bit cheaper than epoxy but other than that I can think of no advantage. Here is a couple of photo's of the 109E that I did, the first shot is with just the gel coat sprayed, the second photo is with the chopped strand matt in place.
