A Little Vacuum Bagging

[jrandy]

Today I am glassing up the bits for a Jim Michalak designed rudder for a PD Racer sailboat
www.pdracer.com
It is going good and I took some pictures and wanted to share the process so far.

Materials:
Vacuum bag (pink),mastic/ bag seal (gray), peel ply (green), breather (white), plywood bits, surplus store fractional HP Gast vacuum pump with gauge,resin trap, and bag fitting, 4oz (135 GSM) E cloth, Greenroom Old#7 resin, drafting table donated by neighbor w/ electric lift (hehehe electric glassing stand here I come...)

Pictures:
1. Gathering materials, happy I had enough of everything to keep going
2. Cutting out materials, weigh glass cloth to calculate resin amount (in this case 185g cloth and around 300g mixed resin, more than normal to allow plywood to soak it in first). Cut bag and set mastic
3. Laminated bottoms, peel ply, breather, flipped, and now laminating tops. Seal bag after finishing stack-up.
4. View of 36" x 60" (.75 x 1.52m) bag at 23 inches Hg (.75 bar) without even turning off the fan or radio to listen for leaks. Hard I been using poly film and cheap tape this would have not been possible. Pump and trap go on the floor after picture.

It takes a little longer to set up versus 'free' laminating but I get both sides done at once and got to soak and compress a couple spots were the plywood to plywood laminations were not the best.

Bagging materials and fiberglass cloth were from the local composite supply house. Greenroom resin was shipped in.

If anyone else has some vacuum bagging tips and pics, feel free to add them here if you like.
Happy Bagging!

[PonoBill]

Looks VERY efficient and looks good except your bag looks a lot tighter at the bottom where the connector is than at the top, where there are some loose-looking wrinkles. Might just be the picture, or you might have a little leak at that end and not enough breather flow to make the bag pull down anyway. Maybe next time lay a piece of spiral tubing down the middle between the pieces to make sure you get the vacuum well distributed. Don't put it ON the pieces, you'll get a line in your glass. One of those things I wish I'd learned from someone else instead of experience.  You might also want to add some pleats next time. It's not a huge piece, but pleats in the corners keep the bag from tugging, and one in the middle of each long side would be nice.

[jrandy]

Thanks for the tips Bill, I will read up on pleats. Sometimes I try thicker stuff that could use more 'give' in the bag especially when I don't have the good stretchy bag film. I have some old stiff polyethylene hose that I could rig for manifolds too.

My intent was the connector was to be down in between all the pieces and manifolded to all 6 pieces of breather. By the time I got done messing around it ended up on top of one part but with 2 or 3 layers of breather...so I did not get a 'hickey' on this one this time. I smoothed the peel ply with gloved hands before I placed the breather and checked the bottom of the bag while it was drawing down so no big creases either.

5. Removing peel ply, feels and sounds like shucking corn
6. Parts waiting to proceed to next step

[PonoBill]

That ripping sound is identical to the sound of tearing up ten dollar bills.

[jrandy]

I cannot say I have ever ripped up ten spots Bill. Those are still good for lunch money around here.

So instead of spending 10 minutes and 20-something dollars US ordering a mast track, I designed one in Fusion360 (over a lazy afternoon), milled the core (1.5 hours) , double layer bias cut cloth, vacuum bagged (3 hours), cleaned it up (half hour) and realized there was an error in the design where each of the the end bosses are about .040"[1mm] too tall to allow the halves to cinch around the screw plates.  Just think, in another couple hours I'll have something to install and eventually break.

Good thing this is a hobby and not my living.

[PonoBill]

The PD racer looks like a fun project.

My most favorite thing about my penchant for making and repairing stuff myself is the sense of accomplishment and security it gives me. My least favorite thing is that I rarely get anything even close to right the first time. GF2 is sitting on my truck waiting to get dragged around to see if it works at all. Every time I look at it I gag a little. When people ask me how I know how to do so many things I say "I make mistakes as fast as I can". I outdid myself on the entire Geezer Foil project.

[jrandy]

I added a 1/2 x 1/2" plywood flange and some aloha fabric and glass to make a larger surface for the base to contact. I am hoping this will help it look a little less homemade and last a little longer. One more round of glassing then onto the board.

[surfcowboy]

Man, that's nice. It's gonna be wild to see what people end up making with all these new tools.

Now that I'm getting into Fusion360 I need to revisit that Futures installation jig as well. You've inspired me.

Pono, keep the faith on the GF. I have high hopes for v3 and all the versions will be fun to do.

[jrandy]

PonoBill, I am also looking forward to seeing the Geezerfoil (TM)(?) in flight
Surfcowboy, you were so close the last time we looked at the templates. Making the revisions should seem easy after you have been working on foils.

It's good I have this mast track to work on. I am working through some back pain and have doctor's orders not to lift heavy stuff. Hopefully it gets better since the PD Racer is languishing and only needs a few hours to complete.

Glassing the top surface make the whole assembly much more solid. Even with the plywood flange the sides could be deflected with moderate pressure, not so anymore.

-Trimmed the outside using a band saw to get within a 1/32" and then a 7" sander with a hard backer to kiss the edges
-Trimmed the inside using a flush trim bit on a trim router followed by a couple swipes of sandpaper

[jrandy]

The boat parts are fill coated and I went after the overlapped and frayed edges from bagging. Perfect sanding weather: 20 degrees F cooler than normal and a 20 mph wind blowing the dust away from me.The worst was the handhold on the leeboard. I had to get out the template and big router to remove all the seepage and big chunks of epoxy+cloth+breather and then re-chased the edges with a small router with a small round over bit. Next time the handhold will be last, if at all.

[PonoBill]

Sanding sucks. No way around that, unless you hire someone.

[jrandy]

Sanding sucks. No way around that, unless you hire someone.

I agree. That is why many of my non-board projects feature a single fill coat with only the big boogers sanded on the edges.

Today was bagging and fill coat the back of the mast track and sealing the edge of the boat parts.

I did not take any pics...but I did learn how to use the Physical Properties window to make my Fusion360 file look like wood followed by the Insert>Decal command to add in the aloha fabric after I scanned in a scrap piece.
 

[jrandy]

The mast track is installed and survived a session of up-hauls and an equal amount of slow-speed wipeouts at a fun lake day with my daughter. I am thinking I should pool-noodle my SUP rails to absorb the mast flops.

They say most accidents happen at home...I would agree. I managed to ding the longboard my daughter rode 2x unloading from the trailer, once into the foam. Then I proceeded to open a garage door, that bumped the bottom of a CF windsurfer, sliding it off the rack and onto the lip of an open toolbox, gashed a good inch deep.

Enclosed are pics of the track and my ding montage.

[PonoBill]

Geez. I thought I was the only one that does that kind of stuff. I have two board repairs to do that originated with me ham-fisting them during loading.

[TallDude]

One of my board racks has a pointed 2x4 wood edge. It punched a little hole in the bottom of one of my race boards. While I had it out on my shaping stands, I figured I'd fix a few other non-leaking dings and scraps. I got a little careless with the sander while doing the patches and made a bigger hole. I finally got it all patched, then took it for a paddle. When I was putting it back on the rack, that dam pointed edge punched another hole in the bottom     . I immediately took my rasp to the 2x4 and rounded off the pointed edge. Still have to do the repair.... again.....