I thought I might make a build log for the first boat I’ve ever built. I decided to do a footy Razor, to keep build costs down and to hopefully see it through, since I’m a novice at boats.
So far I have purchased the following:
2- 1/32"x6"x36" sheets of balsa
1- 1/8"x4"x36" sheet of balsa
2- 3/32"x3/32"x36" square balsa sticks
CA glue
Elmers Carpenters Glue
I cut out the patterns and taped them together to get a feel for how it would go with wood. I then printed out and cut another set for applying to the Balsa. I modified the bow angle a little and the bottoms to match the change. I used stick glue for paper to adhere the patterns to the Balsa. I cut the patterns out of the Balsa using an Exacto knife. I tried the scissors, but it’s easier for me, with the Exacto. I have done other types of wood models and I’m familliar with an Exacto knife.
Below are a couple of photos of the patterns. This will probably be a long build, just because of funds. After I assemble the hull, keel and rudder, I will have to wait a couple of months to buy the servos, radio, etc… So the thread might be gone for a while… But I will try to see it all through and keep updating as I can.
Added - I just finished gluing it together. Harder than I expected. I had to use CA & I’m not familliar with it, but it’s glued now. I used Wood glue on the inside seams for now… Here’s a couple of pictures.
Well I did a little more to the build today. Did some fine sanding on the outer hull, primed it to see the rough spots and used filler to get it smoother. Also cut out the deck. I cut it larger than the pattern because I’m going to put a slight bow in it.
Just one pic for today…
I will start building the keel, rudder and inner components sometime next week… It’s nice to make something again with wood.
Thanks for the thread and pictures - it seems to be going very well and you are clearly at home with wood.
Razor is a sweet boat and IMHO will take a beginner a long way in the class. When the time comes it will pay to keep weights of equipment fairly well to the rear - this chiefly means the batteries.
I have little doubt that Bill the designer will be reading the thread - he would probably appreciate an email anyway as you progress. We owe him a lot of gratitude for making his designs available.
Look forward to hearing of your progress, and it is instructive to hear evenof the debates you may be having with yourself about internal fixings, etc. Are you going for a transom-mounted rudder? Renovable of fixed keel?
Whoa!! Whoa!! Whoa!! Get rid of the Elmer’s glue!!! Most “carpenter glues” are not waterproof. They have no place aboard any boat. All you should need is some CA glue (it’s nice to have both thick & thin) and some 5-minute epoxy (the small, cheap, two-tube package from the hardware store will suffice). A balsa boat can be soaked with spray on clear polyurethane to seal the wood.
Ok, but questions… If the exterior of the boat is sealed, why not wood glue?
Just trying to understand about this stuff. I’m not knocking the post, just asking questions and seeing if my thoughts are way off here…
First of all I have been told many times that CA is bad for balsa, it makes it very brittle and the balsa tends to weaken right around the glued area. This is from model airplane experience, none of the airplane guys will use it around here and I have seen it too, since I started with CA on this hull and noticed how brittle the wood got. Is that not an issue?.. Also CA is not waterproof either is it? It will dissolve in water after a short time from what I’ve seen?.. I had understood that CA was used because it was fast setting and speed up the glue process… There are more waterproof versions of wood glues. TitebondII is supposed to be good. Epoxy is an option. I’ve never tried it. I can try that.
If the boat has been sealed inside and outside with an epoxy or other good finnish, would it not matter about the glue? Just trying to understand, although I do understand that nothing is totally waterproof. Water molecules that are already in the wood will work from the inside and water molecules can get through most every finish? (supposedly).
Your one guess was right, somehow a little water can get in. Maybe from deck hatch area or near deck hole for mainsheet or mast tube. And with wind gusts and a wild ride, the bows are known to become submarines.
Hold on Justin, you may have some fun rides as shown on the Footy site Photos section.
I used the 5 minuter epoxy w/a little microballons mixed in.
Just enough to let her sit at the waterline (nominally the bow chine and transom point touching the water) is a good overall weight.
But then biassing the weight well to the stern is then the hot setup so that you enjoy downwind sailing. (Most footys and all razors bury their bow downwind and get hyperdarty)
From memory my bulb is about 180gm, and seems pretty nearly right, and the original setup had one standard servo, and one mini (probably 20gm). I have now shed a lot of weight from the servos, cells and rig, but don’t feel the need for more ballast. My need is to replace the nut behind the wheel with a talented driver
Justin,
Indeed, CA is not waterproof & it will ultimately fail if subjected to enough moisture. Carpenter’s glue is even worse because it’s boiled cows (or some evil derivative thereof). I use CA just for the sheer convenience of its fast cure time. Epoxy would be a superior adhesive but it’s obviously a more time consuming choice. A good compromise that seems to work is to assemble the panels with CA, apply epoxy adhesive filets to the interior seams & then coat the entire thing inside & out with laminating epoxy to seal everything. I’ve never really noticed any problems of CA making balsa too brittle for toy boats (maybe because I always slop epoxy on everything). Aircraft must certainly be subjected to much more stress than a 12” boat. More likely than not, the biggest stress on a 12” boat is toting it to the pond. Once they’re in the water they’re fairly safe. You could certainly use an alternate adhesive such as Titebond but I don’t really see the point. Epoxy adhesive would be a superior choice, especially if your plan was to coat everything in laminating epoxy. The two would be capable of chemically bonding to each other, at least for a while (upwards of a week, the longer you wait the less chemically cross-linked the bond between the two will be). I personally use 4 different things on a toy boat; thin CA, thick CA, SuperBond epoxy adhesive (with the medium activator) from FGCI and 3:1 ratio laminating epoxy from the same folks. FGCI is Fiberglass Coatings Inc. in St. Petersburg, Florida U.S.A. I hate to sound like a salesman for their stuff (or a broken record) but neither do I like to see people get swindled on epoxy products. The SuperBond adhesive is so wonderful to work with it defies description. Actually I’m lying, I have described it, there is a thread on here somewhere entitled, “In Praise of Products”. If I had to make a top ten list of “Miracle Products”, SuperBond adhesive would certainly be one of them. Loctite threadlocker in “stick” form would be another but that’s a slightly different saga. Since I have lost count of this evening’s ration of Heineken (Hey, it’s prescription), I believe I’ll add one further magical marine product; good old 3M 5200. It’s more of a big boat thing but I have seen it used with marvelous results on Soling One Meter hull to deck joints. As a final note (on the broken record), if you feel that the boat building bug has bitten deep enough, I highly recommend laying in a supply of Superbond adhesive (the small cans will go a long way) & say a gallon kit of the 3:1 laminating epoxy. You’ll blow a hole in $80 but you can build an entire fleet with a gallon of goo. If possible keep it in the refrigerator, it will stay fresher longer. Often times this is not possible due to objections from the major domo. In that case you’ll have to adapt. I look forward to seeing further progress of your build.
May I weigh in with a strong recommendation to use balsa cement!
Its light, quick drying, cheap and easily made. It also makes you happy as you use it, Balsa cement joints are stronger than the wood, totally waterproof, can be sanded easily (and can always be opened again with a dash of nail varnish remover:D)
As I know you know, simple generally wins it in the long run
Just be sure that the location of the rudder tube leaves enough clearance with the transom for the steering arm to be mounted and pivot (with the pushrod or clevis attached)! Don’t ask why I mention this…
I think he means solvent based acetate cements such as used to be sold by Ambroid, Testors, Pactra, and Duco (remember that one?) to name a few. All of the white & yellow glues I have seen (like Elmers, Titebond, Sobo, & Aileenes) can be dissolved in the presence of water (some very quickly, others more slowly), even if they claim to be weatherproof or water resistant. ACC (CA) and polyurethane glues cure by the presence of moisture, and any breakdown would occur very slowly and only in the case of long term direct immersion that would severely weaken the balsawood’s fibers first. If the hull is reasonably sealed by a coat of paint or a resin/glass cloth coating, you shouldn’t see any problems with ACC or polyurethane given the relatively short time a Footy spends in the water, and their fast dry times will greatly ease construction by eliminating the need for a lot of clamping and/or pinning.
Try Lumberjack Polyurathane glue. Its completly waterproof for both fresh and salt water. The only down side is it can be messy if you put to much on the joint. Bob
Before your time, evidently:D
Balsa cement is what sailtwister says - basically celluloid dissolved in light solvents and called things like Ambroid in the US.
You can make it by dissolving table tennis balls in acetone, but people might look at you a bit funny. Did we all know that table tennis balls are the last remaining (non-military) use of celluloid?
Its ideal for assembling balsa Razors - but Justin is well past that point, I think
Boy what a discussion about glues! There’s a ton of them out there and more than one type will work. I think it’s obvious that everyone has their favorite too! Thanks for all the discussion about glue. I think I should have made it a seperate discussion.:rolleyes:
As far as the build, yes the hull is already together, so the glue issue is resolved there, but I have a lot to look at for future building…
As an Update: I have not gotten to do any more building, but I have gotten Christmas early, from some wonderful members here:)
I have gotten together some parts to finish the build. I can make the sail now (MacRig) and the Rudder. I need to wait till the keel bulb comes in before doing the Keel. I also need to wait to do the interior build till the Keel is in place, so I’m not doing a lot at the moment…
But I am still working on it…
Tonight: I decided to do the Rudder.
I used 3 pieces of 1/16" balsa for the rudder. I used an aileron rod with 4-40 thread and a brass tube. I used a 3\4" x 3\4" piece of balsa inside for the support/guide block. I fit the block to the transom/hull and drilled it for the brass tube. Then I used Epoxy to glue it in. I cut the brass tube and glued it in the block/hull. I cut the balsa and figured out the shaft length for the rod, then I cut the rod and made a U shape where it fits in the rudder, so it won’t pull out. I cut the form of the rod out of the center piece of balsa and sandwiched them all together, with the rod in place and glued them with Epoxy. I used a 4-40 plastic washer on the underside of the hull and the top side of the block for wear plates, to keep the movement smooth. For the arm, I used a Futaba micro servo arm and used two nuts to lock it down. I still need to cut the rod end yet.
What’s good about the first boat is learning all the mistakes. I should have done a couple things differently, but I will still be able to make it work, not just the way I should have… That’s part of the fun too, is learning what not to do next time…
Andrew,
I actually still have 3 wooden model boats that were constructed with Ambroid. The term “balsa cement” is apparently a UK term. I have to admit though that none of them have ever had a glue related failure & that certainly says something for Ambroid. I gave it up when I switched to “Hot Stuff”.
I didn’t know that! However, I think there is a difference between acetate and celluloid. The story I heard was that Ambroid was originally made by dissolving old B&W Acetate movie film, resulting in it’s amber color (hence it’s name), which apparently had a relatively short lifespan as film, and this was one of the reasons they switched to celluloid for the movie industry. However, I would suggest that if acetate and celuloid really are the same, it is still being used in the film industry, since there are still many older movie theaters in this country that haven’t been able to afford the new digital technology. I think most of the actual filming process is still done on tape (shooting & editing) but then converted to film to distribute to the older theaters.
Sorry for my part in the gluing of your build log.
Thanks for the pics of the rudder assembly installed - looks the business!
Are you just clamping the tiller arm between two nuts on the threaded rudder stock? I have this arrangement on a steam boat, and guess what? It wanders and allows the tiller to slip.
As a tiny mod which will make this secure add a tiny dollop of silicone sealant to the threads where you tighten to clamp the arm - it will act as both a thread-lock and partly as a glue. It can always be undone at a later stage if necessary (more easily than cyano)
I would always use balsa cement for this (Ambroid) since it swiftly sets hard, and can be changed later with a dab of acetone (nail varnish remover) on a paintbrush.
I guess that the tiller arm will run across the boat if the rudder servo will be ahead of the rudder somewhere. Is there room for it to swing say +/- 45 deg without hitting the transom?
Or are you fitting the servo alongside the rudder with the pushrod running across the boat?
People I respect suggest ths the rudder movement needs to be about the same as the servo rotation, or a bit less
You mention not pushing on with the keel since you want to fit the bulb first - if you go for Marc’s creation, I think it has a slot molded in, and you would be able easily to fit this later (if you wanted)
best regards,
andrew
I note that you are a couple of hours from Houston - I visit there from time to time - wonder if we could have Razor race in a municipal fountain, or whatever. I also saw that Houston recently had a big boating lake called Houston.
1- Ha, I was going to rename the post “The Glue Pot”
2- The rudder arm is screwed onto the shaft and lock with the nuts, I used a dab of CA on the top nut. The bottom nut is at the bottom of the thread, so it does not loosen.
3- Yes I will have to use the servo on the side and move the arm across the boat. Next time I will know to do the rudder different, to have more clearance.
4- I am thinking about the keel still, many options and will work on it, but not till next week, so the bulb will be here then…
5- I am about 6-8 hours from Houston, if we both ever get around at the same time, Sure…
