Fiberglass + Foam: A Tutorial and Discussion

[HilldaFlyer]

Now, could this be a good "tape and fly" solution for fiberglassed airframes? I could see this being useful in the multirotor world too for field expedient repairs.

That was pretty good...

I'm curious about what appears to be water-activated "glue". My opinion is that for fiberglass skinned foam board airplanes, the Scotch transparent duct tape works really good. Packing tape doesn't seem to stick as well (depending on the resin that is used).

Would probably do really well for in the field multirotor repair... like a broken boom.

I should look up what the shelf life is after opening the package... with the humidity in the NE, I bet you'd end up with a hardened roll.

 

[Dave.E]

Over the last month at least the link to Thayercraft has not had not been working. "Website not available". Anyone know if it's down forever or have a good alternative?

 

[bstanley72]

Over the last month at least the link to Thayercraft has not had not been working. "Website not available". Anyone know if it's down forever or have a good alternative?

I've noticed the same thing. I've bought some glass off of ebay:

http://www.ebay.com/itm/3-4-oz-fibe...676784?hash=item19fe3e4770:g:s28AAOSwKrhVXwJf

Search around a bit and you can find different weights.

 

[HilldaFlyer]

I've noticed the same thing. I've bought some glass off of ebay:
Search around a bit and you can find different weights.

Steve Thayer is still in business and he is a really nice guy. I just purchased a lifetime supply of cloth. I had some great email exchanges with him to arrange my order. You have to understand that his main business is to sell huge lots of thousands of yard to builders. He runs his little website off the remnants because he loves the modelers, like us. I'm sure you can understand that he isn't a webmaster, just a regular guy offering a great product at a great price. If the webpage is down, just email him (thayercraft(at)cs(dot)com). I've just emailed him letting him know his page is down.

Just noting that the ebay above is $4.61/sqyd, Thayercraft for the same stuff (50" wide 0.73 oz/yd) is $3.96/sqyd, but you have to buy 10 yds. That will last a while. I purchased 20 yds 3 years ago and just ran out.

 

[bstanley72]

Just noting that the ebay above is $4.61/sqyd, Thayercraft for the same stuff (50" wide 0.73 oz/yd) is $3.96/sqyd, but you have to buy 10 yds. That will last a while. I purchased 20 yds 3 years ago and just ran out.

Yes, Thayercraft is a better deal per yard for sure, the ebay stuff is nice when you're like me and not sure what weights to get because they sell in smaller lots. This allows you to experiment around. Once one lands on the weight they prefer then Thayercraft is the way to go!

 

[RCman50]

HOW MUCH POWER... IS ENOUGH POWER?

Hey Guys,
Here is a picture of the hot wire bow I built with stuff I had laying around the shop. Nothing special. used some wood, thumb screws, blind nuts on the rear if I want to take it apart for travel, I doubt that will ever be needed but ya never know, a spring and some wire with crimps to adjust the spring for tension and nichrome wire for cutting. It's length is about 33'' so I can cut 30" sections. This is my first bow so I don't know if that is an acceptable length for a wing cutting bow, I also wanna build a "slingshot" style handheld trimmer/shaper give or take about 6" wire length. Here is the plug that goes to the power source for quick disconnect. When I find the desired power supply to give me the heat I need I will redo some things and want to add a dimmer to control the heat. Here's where my question comes into play, How much power do I need? With this current setup the wire is just barely getting hot enough to cut the foam, but it does cut. What I want is like I said overkill heat and then control with a switch of some sort. I know you can use a LIPO or XBOX power control but I'm looking for something I have already that's FREE. You can see my power control unit is 12V 4.15Amp 50Watt. What needs to increase to get more heat, the amps or the watts? Also I have 3 spools of nichrome wire I got from ebay, 22, 26, and 28 gauge. Let me know your thoughts, criticism, both good or bad is welcome please as I built this a few months ago and am just getting to mess around with it now as the weather is perfect for it.

 

[willsonman]

Using Ohm's law wheel, constant volts (12) with increasing amps will give an increase in watts. My car battery charger uses 12 and 6 volts but I use the 12 volt setting. Generally it uses 4-5 Amps (~50W) and is generally sufficient for my 18-20 in cuts. Longer wire will require more current (Amps). I do not recommend that you try longer than that is the wire sag tends to be more problematic unless you are using a professional bow.

To regulate your temperature you can go with a BRUSHED ESC and a servo tester but a dimmer switch on that power supply will not do as the brick is self-regulating. Hope this helps you out.

 

[RCman50]

Thank You Wilsonman,
So in your opinion I would get better results cutting my bow down to 20-22"? I made it the size it is (roughly 33") so I can cut 30" panels so a 60" aircraft would only need 2 pieces. I will keep searching around for a different power source that I can adjust the temp on. I didn't realize it is a self regulating power supply and I wouldn't be able to control the temp with a switch. Kinda makes sence now but I'm not very good with electrical stuff. I'll start searching for an alternative way to power my bow. Do you (or anyone else reading) see any other issues I may have or can pose a problem with my bow? After I get the power figured out I got tons of foam to practice on and a few different materials to mess around with as airfoil templates, masonite, thin ply, thin aluminum etc. I moved out of my apartment and into a house with a shop again so 2017 should be a fun year for scratchbuilding. Bought a bunch of fibreglass as well but haven't done any glassing in quite some time since fixing my snowmobile hoods but I have a good grasp on that reading you and other community members threads that glass there work. Ok, Thank You and have a happy and healthy new year.
Dustin.

 

[mchambers324]

Looks like the link that was originally posted for sourcing fiberglass cloth is no longer working... Any other sources? The ebay link that bstanley72 posted is still working, so I may use that if nothing else. Really really interesting stuff man can't wait to give it a shot!

-Michael

 

[willsonman]

Hmmm. Thayercraft has been supplying for years. The site has been problematic in the past. You may want to give them a call. (336) 889-8088

 

[HilldaFlyer]

Looks like Thayercraft's website is still not upgraded yet. I emailed Steve a few times when I ordered about 6 months ago and he was revamping his website...

On Mon, Oct 17, 2016 at 6:56 PM, thayercraft thayercraft(at)cs.com wrote:
I'm doing a whole brand new one with website x5. Crazy time consuming. Fun but lots of small stuff. Thanks. Steve Thayer

Pop him an email and he'll sell you what you need.
Here is a little inventory list of the stuff I usually get from the last time his website was functional:

Style	Width	Finish	oz/yd	Length	Price
104	26	643 Silane	0.56	100	$206.43
104	26	504 Volan	0.56	100	$208.04
104	26	643 Silane	0.56	50	$116.43
104	26	504 Volan	0.56	50	$126.04
104	38	643 Silane	0.56	20	$76.43
104	26	643 Silane	0.56	20	$56.43
104	26	504 Volan	0.56	20	$58.04
104	38	643 Silane	0.56	10	$49.43
106	56	Silane	0.73	50	$127.04
106	50	504 Volan	0.73	50	$127.04
106	50	504 Volan	0.73	20	$95.04
106	38	504 Volan	0.73	20	$75.04
106	38	504 Volan	0.73	10	$39.04
106	50	504 Volan	0.73	10	$55.04
106	44	504 Volan	0.73	20
106	44	504 Volan	0.73	39	$74.00
108	50	Soft Silane CS-310 for epoxy	1.4	100	$169.80
108	50	Soft Silane CS-310 for epoxy	1.4	50	$118.80
108	50	Soft Silane CS-310 for epoxy	1.4	20	$62.80
108	50	Soft Silane CS-310 for epoxy	1.4	10	$49.80
1080	44	Silane for epoxy	1.43	100	$149.80
1080	38	Silane for epoxy	1.43	100	$129.80
1080	44	Silane for epoxy	1.43	50	$103.80
1080	38	Silane for epoxy	1.43	50	$89.80
1080	38	Silane for epoxy	1.43	20	$47.80
1080	44	Silane for epoxy	1.43	20	$55.80
1080	38	Silane for epoxy	1.43	10	$37.80
1080	44	Silane for epoxy	1.43	10	$43.80
1280	44	Silane	1.6	25	$52.80
1280	44	Silane	1.6	50	$74.80
1280	44	Silane	1.6	100	$127.80
120	16.5	538	3.16	176	$176.00
120	50	497A	3.16	100	$347.97
120	16.5	538	3.16	50	$60.00
120	50	497A	3.16	50	$184.97
120	38	504 Volan	3.16	169	$507.00
120	16.5	538	3.16	25	$35.00
120	50	497A	3.16	20	$84.97
120	60	504 Volan	3.16	50	$316.00
120	60	504 Volan	3.16	30	$213.16
120	60	504 Volan	3.16	20	$163.16
120	60	504 Volan	3.16	10	$93.16
220	50	CS-724	3.22	10	$37.20
220	50	CS-724	3.22	20	$52.20
220	50	CS-724	3.22	50	$101.20
220	50	CS-724	3.22	100	$189.20
220	50	Volan	3.22	20
220	60	Volan	3.22	10	$52.20
220	60	Volan	3.22	20	$72.20
220	60	Volan	3.22	50	$132.20
220	60	Volan	3.22	100	$252.20

​

 

[mikeporterinmd]

horizonhobby.com is carrying lightweight fiberglass cloth. They also have the eze-kote resin. I haven't used this yet.

Mike

 

[willsonman]

EZE-Kote is overpriced WBPU... more like sanding sealer... save you money.

 

[RCman50]

I have a question?
I am revisiting this project after trying a propjet awhile ago. I am having trouble with my foam still melting when painting/priming parts. Thats why I scrapped the propjet project. I'm doing everything wilsonman describes in the forum post. Lay my 1.43 cloth down, poly, one coat of bp poly mix, sand and a second coat thinner bp poly mix sand again and prime. Its heartbreaking after putting all the time into a part to have melt marks in it. All I can think of is I'm possibly over sanding. My parts feel smooth as glass, no pun intended, when i prime.
Any suggestions?

 

[willsonman]

Bally PA?!!! Small world! I know where that is!

It does sound to me like you are over sanding a touch. After sanding the poly mix, try sealing it with just poly. Do a coupld of very light coats and then sand again. You may find that this seals a bit better.

It is also possible that you are not mixing in enough baby powder to plug all the holes. Mine is like a heavy corn syrup. Think maple... but one step thicker. There have been times when I just put on a nitrile glove, pour it on, and smear it with my hand to do a little forcing of the baby powder into the weave. Messy, but effective. Doing that just makes more work in the sanding so I do not recommend it.

 

[RCman50]

Born and raised. Lol. Thank you I'm gona start doing just some 8x8 or 12x12 samples until i get it right. Off topic but curious how you know where bally is? If this is inappropriate for the thread nm.
Thank you wilsonman, man of all answers.

 

[willsonman]

Haha! Well, I have a lot of answers but hardly all of them.

My grandparents lived there. Well, they were just outside, on Kulps Road. My Grandfather was very active in the community and was involved in getting the water treatment plant there for better water quality. They are buried at the cemetery of Christ Lutheran Church. Melvin and Rose Smith. Spent a lot of time there as a kid in the 80's and loved the local ice cream as well as the gold toe socks, before it closed. Good times.

 

[RCman50]

Yup you said all the key words. Lol. Socks, longacres ice cream, cows. Awesome man small world. Cool.

 

[jhitesma]

If you are thinking that you can just use the WBPU and BP mix to fill the weave... just stop. Do not try it. The problem is that the epoxy cures to such a smooth finish there is next to nothing for the WBPU to stick to. I've tried pre-sanding the surface and it still does not work well because you are trying to get the mix to stick to the little pits where the sanding will not get to.

So I've finally been experimenting with fiberglass the past month or so. And some local guys are talking about doing some serious combat soon so think I may finally get around to building a bloody ripper

This thread has been very helpful in my experiments...but I was just re-reading it and saw the bit about not using WBPU/BP to fill the weave when using epoxy...and...well...I tried that and it seemed to work great for me.

But - the big difference is I used peel ply (well, <$2 per yard polyester dress liner fabric from walmart) when doing my laminations. This has a few benefits. First it soaks out excess resin from the cloth - most of what I've read about composites emphasizes that excess resin doesn't really add strength just weight. My friend with the composite full scale plane keeps getting reprimanded by his mentor that his layups are too rich and he's overdoing it with the resin. Though I've found conflicting info about just what an ideal cloth/resin ratio should be (mostly based on application since adding it on top of porus materials you loose a lot of resin into the base material.) Anyway, the other nice thing about using peel ply is that it leaves a rough surface that's perfect for the next layup if you're doing multiple layers...and seems to let WBPU/BP bond to it just fine.

I tried it on two panels, one covered in the 1.43oz thayercraft cloth and one covered in the 6oz bondo cloth. The bondo weave is a LOT harder to fill...but both of them smoothed out quite nicely with the WBPU/BP on top of epoxy. I used two different epoxies as well...the Thayercraft cloth was done with some really nice MGS epoxy a friend gave me while the bondo was done with BSI 30 minute since it was the most economical I could find at a local store. No problems with the WBPU/BP adhering to either with no special surface prep.

So just thought I'd share that.

P.S. - I also figured all this experimenting would be good practice to start getting used to epoxy/FG since I'm really itching to finish that plans built balsa RV-3 I started 3 years ago and really need to make more progress on!

 

[Sly Fox]

Question, can you glass a ft model after the build?