roknHS

Biker,
My field box battery is a Lawn Tractor battery, 12V. It is about a third bigger than the size of a Motorcycle battery yet, much smaller that a small 12V Car battery. I think mine has 450 CCA (cold cramping amps). So, it is 12V, has more boost than a Mcycle battery but less than a 12V Car battery. All that info to tell you the Dynatron, on a good 12V battery, will easily start your G-26. Fact is, the Dynatron is overkill for a G-26. Mine will start a 50cc engine with a 12V battery. The Dynatron is very powerful and weighs about a third more than a regular heavy duty starter. I think there is a lot of copper wire inside......................lots of windings.

Rellic

Ken, I have a Dynatron on a 12 V 3200 Amp Battery gutted out of a C/T Emergency Automobile Booster Pack / Power supply. It will spin My MVVS-35 My (on a fresh charge and a good back stroke head start) DA-50 and My Saito 180's. All of witch reliably hand start, but the Dynatron will spin them on an off day.
I made 24V field box with two of them batteries and have not had a need to use it since I built it. 

Brian T.

G.P.

My Feedback: (1)

Well I sprayed out a small can of the expanding foam. It looks like the correct amount to do the forward half of one float. It felt pretty light for it's size, but I weighed it and it came to 10 oz. For two floats that is really going to add up.

For now I mixed some PU glue (gorilla glue) and water to make it foam lots, and smeared it around all of the joints in the keel area. That has added a bunch of strength, but I'm thinking that just glassing the bottom of the floats may be the better way to go for strength/weight.

bikerbc

I don't understand what you did with the Gorilla glue in the keel area....Did you paint a layer of glue down the centre of the float on the outside ? Would this interfere with glassing the bottom ? I glassed the bottom of mine with 4.5 oz. cloth and just 1 coat of epoxy so far and it has made a big difference....The bottom is rough to the touch but I think that may help it to break the surface tension of the water . If there is such a thing...I can always add another coat of epoxy (and another 2 oz. of weight any time I want) ..I have not given up on the foam idea yet...I suspect the canned stuff is heavy...I was looking at the difference in the weights between the different batches of foam products on the spec sheets that Brian sent us and the stuff that expands 15 to 1 is quite lite...I think the canned stuff is way down on the expansion rate making it quite heavy....The only down side with the stuff you mix yourself is of course getting into the float after you have batched it . It will be a bit harder because you don't have the squirter.... Was your 10 oz. sample filling the cavity ? My idea was to only fill maybe the bottom 1/2 and more towards the front half of the floats....If we need to add weight to achieve our C of G we could do it with the foam ..I am guessing 1 cup of foam in each float should do it...That would expand to 15 cup fulls....A person would need to be careful not to blow the floats apart...I think opening up the inspection hatches on the top of the float to gain access would help , maybe even making a couple more. It would be easy enough to make some nice looking covers to seal it back up again..GP you do some nice looking work , what are your thoughts on this ? There is a place locally here where I might be able to pick up some small sample batches of the foam ...I could at least ask the guy and let him know that I am not asking for a hand out but rather just a few small amounts to test so that we would have a better Idea of what we were working with...Somebody I was talking to told me that temperature has a lot to do with the time you have to work with this stuff...I think the Brian would be a big help when the time came to actually do something plus the guys in Salmon Arm that have the stuff and use it should be able to give me some good advice....If I was to have success finding something that looks like it should work I could always ship you some up on the Greyhound .. I should be able to seal it up in a couple of pop bottles and put it in a box wrapped in bubble wrap or shredded paper ..Its a thought anyway...

G.P.

My Feedback: (1)

Thanks for the offer, but you don't have to go through the hassle of doing that for me.

The Gorrila Glue was done inside the float. If you squirt a little water on it and mix it up it expands and foams just like the spray foam insulation. I just put it around the keel area to help tie everything together. I use it on the landing gear plates of my 3D planes, and sometimes it's the only thing left after a crash!

I used one 340 gram can, and just sprayed it out on a news paper. It looked like the right amount for the front (keel forward) of one float. It was just normal expansion stuff. I remember seeing extra expansion stuff years ago, but the local Canadian Tire didn't have any. I'll try the other building supply places latert this week and see if I can find the extra expansion stuff. I guess only filling each float half way like you said would work too. I was just thinking that filling it all of the way up would help transfer any hard landing all the way up from the bottom of the float to the strut attachment points.

I think that the extra hatches are totally doable. Family and work has been really taking a lot of time lately and I've got other projects I need to get done. I'm itching to get this one done...but that usually doesn't work out in my favor. I should probably do it right, or I'll be doing it again. If the extra expansion foam doesn't look promising, then I'll just glass the bottom. That should be more than enough.

G.P.

My Feedback: (1)

Here's an example of Gorilla Glue & water on a gear plate. I did a low snap-to-pancake with my 70" 3DHS Slick a few years ago and this was the result. You can see the gear plate in the lower RH corner, right above the cutters. The gear plate was literally the only thing that was still in one piece that came out of there. The battery tray and all of the formers back to the rudder servo were nothing but splinters.




edit: Sorry, I can't get RCU to upload a pic without getting an internal server error...so I had to hotlink it, and it came out extra big.

G.P.

My Feedback: (1)

I tested a can of the supposedly high expansion stuff. The end result about the same size block of foam, but it weighed 1/2 an ounce less than the standard stuff. I think I'm just going o go with a layer of glass on the bottom, and foam only if I need weight to balance.

bikerbc

Could you post how your weight changes with the floats if at all...I have already glassed the bottom of mine with 4.5 oz. cloth and it has made a big difference . I just weighed them and with the water rudder and servo in the floats the left float came out to 1150 g and the rite float came out to 1170 g . I guess I didn't remove as much epoxy from the rite float . I don't think it will matter much .. I forgot to weigh before I glassed .

G.P.

My Feedback: (1)

Do you mean the CG with the floats and without, or the final weight of the floats if I glass them? I don't have much experience glassing, so they will probably change a lot!

My CG with floats and without probably won't help most people with "normal" setups. I'm running big tundra tires that are over 2 lbs extra ahead of the CG. My floats also have no water rudders and no servos in them. With those setups my CG moved slightly aft with the floats on. It's right at the rear of the recommended CG, or slightly aft. I would have to add a bunch of weight to the nose of the floats if I added the water rudders. My power system is pretty light though, so most people wouldn't have to add as much as me. I'm running a Motrolfly 5320 with a composite backplate (weighs close to the Power 110, but put out the power of the 160 ), and 8s 3800.

pldawg

My Feedback: (6)

I think he was just asking if you weighed your floats before and after you did the gorilla glue.

G.P.

My Feedback: (1)

I see. No I didn't weigh them before. The stuff foams a lot when water is added to it, and I can't see it adding more than an ounce per float.

pldawg

My Feedback: (6)

Yeah, especially since the typical bottle only weighs 2oz itself. And I'm sure you didn't even come close to using a whole bottle.

bikerbc

The Weight I might need to add to the front of my floats concerns me . I have my plane balanced now and when I put the floats on I would like a rough idea of what to expect I might need to add to the front of the floats...If I need to add weight I would like to add foam , just in the front bottom part but as I say I am not sure where I am at for balance . I guess the only sure way to tell is to put them on and balance the plane .. Then take it back apart if it needs nose weight and add the foam...What weight of cloth are you using GP ? Are you using systems west epoxy ? That's what I used and it is easy to work with...After you saturate your cloth you scrape as much as you can back off with an old credit card or a plastic putty spreader like the body guys use and then let it set up... make sure the edges are saturated out past the edge a wee bit .

G.P.

My Feedback: (1)

I have a couple of sizes of cloth from years gone by. I have no idea what the weights are anymore, but i do have some ultra thin stuff. I just use whatever epoxy I can get in town. I'll check out the Systems West Epoxy, but it sounds like the way I was taught anyways. I place the cloth between two pieces of plastic, then squeegee the epoxy around to get the cloth all saturated. Then Squeeze out as much epoxy as possible. It keeps it nice and light without adding too much epoxy that way, and the cloth stays together nicely.

bikerbc

The systems west is a little expensive to get started with but it lasts a long time...You get two pumps that go in the tins and you just pump equal amounts into your mix container .. Like one pump of each or two pumps of each or on and on...It is very easy and works great...I don't think you want to use really lite cloth on the bottom of your floats , I would not use anything lighter than about 3 oz. .. I used 4.5 oz. on mine and it seems about rite .. I just went out and counted the strands per inch and there is approx.. 18 or 19 . I look at my 3/4 oz. cloth and it looks almost like a silk scarf . That stuff is way to lite to give us the strength we need .. The only way it would work is by putting on a few layers and that would be time consuming and possibly heavier .. The light weight cloth is much harder to work with too , it tends to get runs in it like silk stockings .. The heavier stuff just works better all around...I am just following advice from the guys in my club that have been doing this for yrs. and their jobs look great . I have made probably ten sets of floats now and am gradually getting better at it ..I sure like the solid foam ones better than the built up ones...You would think that they would be heavier but they don't seem to be much heavier . They certainly are much more leak proof . I am honestly not sure what the attraction to built up floats is .. There must be something ... Its not time to build because the foam ones take very little time to hot wire out and then covering with glass goes pretty fast..I think it takes less time to make a set of foam floats . I have a set of GP built up floats that I made a while back and I think they are heavier than my foam ones .. Anyway trying to salvage these Hanger 9 floats and turn them into a decent set of useable floats has been interesting and I am not done yet .. I still have to see if they work...We have a big float fly coming up May 26 thru June 2 so I would like to have them on by then... I don't have a lot of time .

Jeepindog

What happened to the discussion on the Super Cub? This turned into a chat about fiberglass. Sad.

bikerbc

Well this is a discussion about the floats for the PA18 if you care to look back a bit. It is related . What do you have to contribute that is Cub related ? I miss it too...I check this forum first in hope there is something new..

G.P.

My Feedback: (1)

+1 Would love to see it instead of trolling comments like that.

Obviously not much flying weather out there yet...or those that can are having too much fun flying their Cubs to post about it on the interwebs. Either way there haven't been any major issues reported yet which is good. [8D]

Jeepindog

I have a set of 8" bush wheels and a 1.60 four stroke twin for my Super Cub. I got my big box last week and I'm making a lot of progress on it. (I guess I'm just disappointed that this thread started out talking about the airplane and then changed into a discussion about fiberglass cloth and expanding foam, since you think I'm trolling.) I'll be back with some pics soon to show you guys the fun I'm having working up this new ARF. It's a beautiful plane- lots of room for adding scale details.

bikerbc

What is the difference between 8 inch bush wheels , a 160 twin , And the fiberglass cloth that we are talking about on our planes? Just because you aren't doing that on yours doesn't mean we should not be doing it on ours...Buy all means fill us in on what you are doing .. I for one am interested .. I have drove everyone nuts with what I have been doing with mine.. obviously..Maybe when you are all done with your assembly you will want to put floats on and what GP and I are doing will seem more appropriate ..

G.P.

My Feedback: (1)

Sorry about the trolling comment, but any post that does not contribute to the conversation and is worded in such a way to provoke an emotional response is trolling IMO. You may not have intended it that way, but it came across that way. Of course tone is hard to interpret on the internet though.

So which 8" wheels did you find? The only ones around that size that I can find are the Airtop ones, which are very heavy IMO. I would love to find some lighter ones.

bikerbc

I have a OS max 160 twin that I am going to put on a BUSA 1/4 Cub that I am building so I am interested in how you make out with yours .. I need to know if a glow driver is required to keep it running when it idols down . GP is not doing anything like that.. I hope he doesn't get mad at us for talking about it .. Are you going to change your tank position so that the spray bar centered with the tank ? I did that with my J3 .. I know it is important...I have all the spec's for the motor if you need them.. I understand yours comes without any instructions as to how to set your valves etc .. They are the same as the Gemini twin... I am debating getting a ASP because they are so cheap ..I have been watching Hobby King and they have been in stock for a while...I don't think there is much difference between the Gemini 160 and the ASP 160 except price .

pldawg

My Feedback: (6)

Yeah, curious what 8" bush wheels you're using. Weather has kept me from a maiden but hopefully we will get a break and my schedule will line up with the weather.

bikerbc

I am also curious about your 8" bush wheels and would like to see a pic.. What did you use for and axel? I was going to go to DuBro's 1/3 scale Cub wheels and I might yet but I haven't picked up a lynch pin for an axel.. Personally I like Du-Bro's 1/3 scale Cub wheels .. I am finding that with the bigger wheels I am having trouble stopping the plane when I come into the pits.. Just a real low idol and it wants to keep rolling...You almost need brakes...It rolls so easy now.. I expect with bigger wheels it would be even worse...You for sure need an on board kill switch...This is on a 1/4 scale Sig J3 Cub with a OS Max120 FS . I have Robart gear on it so it is quite similar to our PA18's

G.P.

My Feedback: (1)

Anybody tried the big bush wheels on pavement? The only place that is mud and snow free at the moment is pavement. I would like to get the maiden done though. I'm a little worried that it won't track straight with the big wheels, and to add to the problem one of my axle holders on the gear was welded with a slight camber in it. It wasn't very noticeble with the stock wheels, but it's amplified with the bigger wheels on there.