Welcome! Need support, you got it. Or share you ideas and experiences.
In Reply to: Re: homemade outboard posted by KenOhki on March 11, 2003 at 00:59:13:
Another frustrating night of work here. I picked up a drill bit sharpener today at home depot because I was tired of watching expensive bits go dull on me. I dilled the pilot holes like you said, the smaller bit seemed to have less trouble getting thru the metal. But then I start drilling with the 1/2" bit. it drills for about 1mm before becoming dull. I sharpen it and drill then sharpen and drill etc. I got to the very last 1 mm of steel to be drilled into the hole then the drill bit chuck starts to slip. I hand tighten as hard as I can but no good. By this time I am getting kind of pissed because I am like getting nothing done. I took out these two vice grips and clamped them on the drill chuck to tighten, I pushed it a bit too far and the chuck breaks with the drill bit stuck inside the drill. I even clamped a vice grib on the bit and started hammering trying to get it out of the drill-it wasnt coming out. Total progress for the night...1/2 of one hole drilled, a dull bit, a broken drill and a bloody elbow (bumped against the sharp steel). I hope things get better after this hehe. Tomarrow I will try to laugh this off, get a new drill and drill bit to finish the hole. In the future I think I will do like you and use a more powerful welder or torch to make the holes.
Regarding the chain, I am not sure why its too fast either. A motorcycle chain does spin that fast as well as a automobile timing chain. Adding more pulleys would be fine for keeping the belt pulle contact, but the idlers are $40 bucks each and makes this project more work. Too much work to find a junkyard and I dont want to wait for ebayers to mail them to me. Things are starting to get difficult so I want to keep this as simple as possible. I love the wood/fiberglass idea, I could make about any shape I wanted. I havent thought much about the housing yet and a going to do other stuff a bit before dealing with that. Perhaps if I ignore that problem long enough it will go away!
I got this perfect metal left hand rotation prop today in the mail, its small and looks to be in the 1-2 hp range. About a week or two ago this guy said he would send me one for free because he was interested in seeing if this would work... so the day was not a total loss. (the prop you see in the photos is right hand)
No updated photos today. As soon as I drill that last 1 mm on the last hole, I will put the bolts in, drill smaller holes for the motor, mount the motor, attempt to measure for the belt, get a belt then start her up just to see what it is like. Do you know how to measure for belts, is it center of one pulley to the other? By the way I am using a stardard "4L"? automotive type belt. Found some drilling tips at the link below if you are interested.
That sucks about the drill bit, Sounds to me like it lost its Temper from heating up, Once the temper is gone, its toast. I have had some luck retempering a drill bit before, bit they are never the same. sounds like you should have used 1 more midsized bit before going with you final size. That really sucks about your drill. Hope it was a craftsman, gotto love there waranty.
On to belt mesurement. I am pretty sure you need the Oval distance of the belt. I would find this by using a thin rope, wrap it around the pullys like the belt would be then mesure the lenght of rope. I am not certain of this, But In any event, Bringing a piece of strin X inches long to the autostore,You will come home withthe closest match possible.
Thats cool you got a free left hand prop. Props can be expensive, I need one for my old 6hp and just cant bring myself to blow 90 bucks on it. Once I get my new 15 hp, Im gonna put the prop for the 6 in the vice and see if I can bend it back into shape some, I know this is a risky thing to do to a aluminum prop, But I will not pay that for a prop. It will most likely crack or break when I do.. However Now, it wont matter as much if I do kill it. Maybe I can get it welded if it does break or crack, ow well, thats another story.
Bought another drill (not a craftsman, I buy the cheapies) and bit and managed to finish the holes. I used slower speed, lots of oil and patience and it drilled right through. Glad that is done. Amazing how much stuff you have to think about when drilling steel, like what you said about its losing its tempering. That string idea is great, I will just take it to the auto parts store and compare until I get a close match. Cant wait to get the belt on and start it up to see if it turns the lower shaft ok and hope that the things doesnt shake itself to pieces. I searched ebay for a 6hp evinrude (is your 6 an evinrude?), no luck. I looked at Iboats.com, guessed that the was 1980 then 1970, the prices were $70-$100-no huge savings there. maybe you can buy some cheap props from ebay within a couple of horsepower then bore them out to fit your shaft or weld it on -maybe not it would be a shame to wreck that motor. What happened to your 6 hp prop by the way? Updated photos below.
Well, actualy, Mine is a 1969 Evinrude 6.5 But I do tend to call it a 6 for ease of typing. Yeah Ive been all over the web, after shiping its always been around 90 bucks total from what I have seen. Its a 2 blade deal, but I dont know the specifics, they are long worn off the prop and cant be read. I most likely could adapt a diferent prop to it. What happened to it? Hmm, well, I bought the boat from someone who probably thoguht he was riping me off. He didnt appear too bright either.. WHen I bought it, it had a hole in the keel big enough to toss a softball through. Looks like he ran up up on some rocks. But he claims the roller on the trailer did it during transport. The motor ( that he said was a 7.5) looked in good shape to me, but what did I know, It was going to be my first Outboard. But later, a friend of mine looked at it and informed me that it was deformed. after looking at his prop, I understood. It appears the prop was run up on a rock or something, I say this becuse it is uniformily deformed on both blades,The appearance of the prop supports my opinion, BUt I cant say for sure.. There was also soooo much oil in the gas, that it would not start. thinking it was just dead, I eathered it, and got it to run, Hoever I put on a smoke show like you have never seen hehehe. SO I imidiatly changed the gas to a good mix and it ran and fired perfectly after burning all the crap gas out.. The trailor lights were also dead, the wireing was the worst ive ever seen,, So I am certain he thoguht he was unloading a piece of crap on me. the only thing I had to buy for it was a new batt for the trolling motor,a 1/2 galon of marien fiberglass resin, some fiberglas mesh,40' of wire and a quart of bottom paint. total repair and paint cost, 45 bucks ( dont concider the batt. repair ) 60 for batterie. However I think I got a steal. 400 bucks for the 14 foot fiberglass game fisher with 3 captains chairs, wide optic fish finder 40 LB thrust foot controled MInKota troler,6.6hp evenrude, 2.5 gal fuel tank,Livewell waterpump and a trailor to boot.Hell the min kota itself is worth 300. And the fish finder another 100, I had a offer of 1000 bucks on it the first day it was in my yard. I almost took it seeing 600 profit, but didnt think I could find a boat with all this stuff for that money around here anytime soon, And I wanted out on the water,, Shore fishing was getting me down. Just prior to this purchase I was concidering a rubber raft hehehe.
Back to your prodject, I dont think it will shake itself apart. You might want to make a small support frame for the prop end of the shaft around your stuffing box. It may or may not want to rise a bit when put it under load outside of its casing, and this isnt a good thing. I am pretty certain your outboard will work no problems. I suppose if the motor runs rough itself, it might vibrate a little but nothing aditional support cant fix if need be. if Vibration is a real problem, You might concider making some rubber mounts for it, Ill get into that at some other point if it becomes necisairy.
Im kinda sitting here thinking to myself. At such low HP, the belt being wet may not be the problem we both beleive it to be. When you get this running, Just for shits and giggles, wet down the belt and pullys, see what that does, then, with a leather glove on grab the shaft and apply preasure to it to see if you can make the belt slip. ( there are other ways to stress it, like sandwiching it between 2 2x4's,) But I think this might be a good thing to check at this stage of the game.
On to a little less exciting point. I was also sitting here looking at your design and something just occured to me, You have made no provision for tilting the motor out of the water. this could cause problems getting the boat in and out of the water, And If you do hit something with it underwater, its gonna hit solid, and potentialy take you right out of action. I always leave my motor Unlocked so it will "kick back" if it hits something underwater. As much as I hate to suggest redoing something again that I already sugested you redo...You might want to once again make a design change to your mount. Perhaps using a heavey door hindge on the horizontal pipe that you already shortened a few days ago. Between the pipe and the mounting bracket. I feel this is a magor design flaw,, I kinda kick myself for not noticing it sooner,when I noticed the lenght problem, However I have also kinda been concintraiting on your problems as they arise on a case by case basis so to speak, This problem wont manifest itself til you are actualy putting the boat in the water and trying to use it.
This is not a manditory change, I mean, it will work one way or the other. I guess it boils down to How much of a risk do you think it is, and how much problems it could cause now that this thought has been thrown into the Mix. Remember, Your welds will be absorbing any shock of this nature. I think you should also plan for a teather, from the motor to the boat, and maybe even a second one on the lower unit, SO if something does give way, it is still attached to the boat, and not on the bottom of the Bay.
$400 is an excellent deal for that boat, I cant find anything even close to that price range out here. I am thinking about a rubber raft though, cant see any way around it I have to use my existing utility trailer and I have to store it in my garage with the trailer and two motorcycles. The decent rubber's out here start at $800..nuts. When you said you used ether to start it up, do you mean starting fluid? I have tried starting fluid in my 1974 mt250 motorcycle but it does no good, it only starts when pull started behind a car. I would love to find something that works so that I dont have to go thru that trouble. Was your 6.5 able to plane your boat? At some point in the distant future and if this thing works I may want build something (not belt driven-gears) with a bigger motor, enough to reach plane.
I did the string thing like you said, turns out it takes a 70" 4L belt. Finished bolting the motor on and put the belt on. I was so excited to start it up and see what happened. I had my wife (who already thinks I have lost my mind for doing this project) make a movie with our new camera. It started right up attached to the belt and pulley's (no prop). No serious vibration problems, the c-clamp handles rattle a bit but I can fix that with a bit of electrical tape. Other than that it was pretty smooth.
I did not think about the motor tilt problem. After reading your post I thought I would just risk it but there could come times when it will bottom out and cause problems-I am going to think about that one-I wish you had broght it up before I made the part! hehe I might just do it again and do it right, worst case if I hit something hard enough it will rip the back of the boat off.
I wetted the belt and tried to carefully grab onto the shaft, it did not slip. But I do not know how much torque I was applying. The bearings I have are not watertight or rated so they have to be eclosed anyway-maybe I could just enclose them. Regarding the stuffing box, I was hoping that the hose would be able to prevent twist, is that what you meant by the support structure? The movie is at the link below, since I do not post movies often I am not sure if will work properly, also you will have to watch it with your head tilted 90 degrees hehe.
Yes, I ment starting fluid. a very bad thing to do to such a small motor, but I was thinking it was a lost cause anyway when I did it. In generaly its a poore thing to do to any motor, but sometimes you have too.. when you tried it on you motorcycle, did you get it into the carb or just spray the air breather? it has been my experience it needs to be prayed directly into the carbs, wile the throtle is in the full open position, then attempt starting in the full throtle position like it was flooded. Have you tried to push start it or does it literaly require the force of the car pulling it to get it to turn over?. I have never had a bike I could not push start myself with a little running start.
About my boat, the 6.5 does not get the boat on plane It might if the prop was in good shape. the total weight of my boat is 6 too 900 pounds with gear, depending if Im alone or not. To be honest, I dont notice much difference when I am alone or when the boat is full as far as speed or handling. this motor seems to move the boat about twice as fast as my 40 pound thrust electric does.
Your movie runs fine, It looks like this prodject is comming together well. from the video it looks like minimal if any vibration.
I was not sugesting you expose the lower unit to full submersion, I just wanted to know how much affect water would have at such low power,, In a car, a little water will make a belt squeel to all hell and back, well, at least in most cases. About how much torque you were applying.. my good hand is capable of producing 48 pounds of crushing force the weaker one ( weaker from a injurey and surgery on my tendon) is only capable of creating 23 pounds, and I am by no means a mucle Dude., SO I would figure 2 hands on the average adult male should be able to produce around 100 pounds of resistance or so, provoded your gloves have reasonable traction on the shaft. Mind you this is from the book of estimating and guessing. ( A book I live by allot ) I would say if you earnistly tried to stop the shaft and failed without the belt slipping, You are in good shape.
I wish I would have forseen the tilt thing earlier too but I wasnt looking at it from that perspective. I bet if we had been discusing this in real time. I would have came up with it sooner, the one drawback to typed communication once a day.. I dont think it will rip the transom off, if anything, I think a weld will give way or perhaps mangle the shape of the lower end if you hit anything. It isnt like you will be doing 40 mph, probably more like 5 mph, depending on what type of boat this gets put on. Here is a thought for you.. Matching a boat to a motor is kinda important. the prop must be at the right depth below the boat. You might need to manufacture some form of adjustable hight bracket deal. something that mounts to the transom like a reciver. the tilt could be designed into this part as well as a way to lower or raise it some in order to occomidate different boats without having to redo what you have. weather it tilts or not, Hight is Very important to preformance. My transom is 15 inches, and requires a short shaft motor. having no boat, you really cant build it custom for your boat, so some adjustability might be a good thing. What is the distance from the C-Clamp bracket to the prop shaft? Looks to me to be about 22 inches or so, For my boat, that would be about 7 inches too deep, Mind you thats just my boat and I am estimating distance from your pictures. But this is kinda a important issue to get max forward power out of your 2 horses. Again, Not a manditory issue, It will function at any depth to some degree. I am sure right now, You just want to see it work, but once you are moving accrost the bay at a womping 2 mph you will definitly start to look for ways to maximize forward velocitey.
I somehow dont see that motor on the back of a rubber raft, for well under 800 bucks you can build yourself a boat. SO far the mini speedboat im designing looks like it will cost under 100 in lumber and fiberglass.From some of the plans I have looked at for wooden 14 foot boats only run about 250 300 in materiels. Mind you these are primarily plywood based reinforced with fiberglass.
thinking about your next prodject already huh? lets take that 250 motorcycle and make a inboard out of it, ( after ya get it starting corectly ) I bet that moter would plane whatever you put it on hehehe. I have been toying with a few other drive mechinisms in my head, Right now, waterjet drive has the most appeal to me. but they also have some sucky problems.
I have reset the timing (points ignition) twice on that 250, each time it started better but still hard when cold. I wonder if I should advance (or retard?) the timing past the setting that the manual recomends because it was made in 74' and perhaps they were used to lower octane fuel then. I put 92 octane in the bike. It will start eventually if I kick at it for 10 minutes or push it for 100 yards..because that is too much work I have my wife pull me started with the car. Once its warmed up it starts up after a few kicks for the rest of the day.
I was thiking about your tilt idea and decided that its pretty important to have. I cut off the pipe on the c-clamp assembly, welded on a big door clamp, a new pipe, and extended the back plate down then braced it with two small pieces of L shaped steel. It seems to work pretty good, I will find out when I reassemble the outboard. I am also getting rid of the 1/2" bolts that support the motor mount. They barely fit thru the holes the 1/2" drill made therefore they bind up bad when I try to disassemble the outboard. going to go with something a bit smaller. I am going to pass on the hieght adjustment for now. You are right in that I just want to get a working machine asap-I will worry about performance issues later. I measured the distance between the clamps and the prop of a 1961 johnson 21 hp seized up outboard that I have to determine the distance I would use. I dont remember what that number was, I keep losing my tape measure but as soon as I find it I will find out how many inches it is. By the way I bought the 21 hp on ebay for $60. I hoped to rebuild it until I found out that you need 3 college degrees and a doctorate to fix the dang thing so I dropped that project. I suspect that its only the lower end that is seized but am not sure. I really dont like the rubber raft idea either, its small, uncomfortable-I would prefere a small jon boat or skiff with comfortable chairs you can lean back in for a harbor cruise. I may be able to rent one but havent found out the details on that yet. Btw I would never ride in a boat that I built, just would make me really uncomfortable hehe. Plus there is alot of know-how there and I am mostly interested in mechanical things. Not a bad idea about using the 250 as an inboard, lots of potential especially with that built in transmission. I think it has like 20-30 hp so that should make things interesting out on the water. Updated photos below.
Your new part looks great. I was hopeing you would do something about the tilt issue. It would really suck after all your hard work to have soemthing happen.. Just think, according to Murphys Law, Now that we have prepared for hitting a submerged obstical, You will never hit one.
I cant really help you much with how to make the motorcycle run, I can adapt it to just about anything you want, But if it stops running or has a problems, I am not your man. I know my limitations hehehe.However, Tailgunner seams fairly knowlegeable, he might have a answere for you if you drop him a email or perhaps if he reads the problem here.
You will have to pardon me a bit here wile I chuckle just a little bit at you for being willing to go out in a boat with a Home made prototype motor, but would not be willing to knock a boat together and trust it hehehe.. You should see some of the stuff my friends and I knocked together and took out in the chesapeak Bay down In Maryland, where I grew up. Ow I wish I had pictures of some of it. OK, Now,, lets see here.. a seized outboard you say.. I am by no means a outboard mechanic, its too bad you wasted 60 bucks, However you might be able to strip it for parts. How sure are you the lower end is siezed and not the motor? I have been checking out some of these electric boats. allot of them seam to have basicaly shoved a electric motor into a regulare lower end in place of the gas motor.
I was thinking about the 250 and got the funniest visual,, You know those water pedle trike things they have? wouldnt that be a bitching ride built around a motorcycle. Probably not the most efective way to use the power, but it would certainaly be a eye catcher. Anyhow..
It looks like you are just about ready to address the housing issue for the lower unit. There are many diferent ways you could go about this. The diferences mainly in the type of joints you are gonna use. I would suggest using mitered edges for most of it. I was also thinking that a triangulare shape to the horizontal lower part would probably be the most efficient. The vertical shaft really dosent matter if its square or triangulare, so for ease of construction, I would probably go square. Hmmm.,, Here is a thought. You might be able to use the PVC for the vertical part. Its really the horizontal part that you will need a access pannle for so, that is really the only part requireing a custom build..It would save allot of fiberglasing..and a good deal of weight too. Huh,, I like that Idea. I think that is the way I would go. Ill drop you a email with a quick pic of how I would go for it. You will most likely have seen the pic before you read this anyway
Its raining dogs and cats out here in so. california. I needed to do some welding before I proceeded to the next step. since I weld outside and its raining I did not get anything done today.
On the homemade boat issue my biggest worry is that it will sink with my wife and I in it, but with the outboard the worst is that the motor will end up on the bottom. (Good idea about the tethering the outboard to the boat, I will definately do that)My biggest worry about losing the outboard to the water is the joint between the pipe and the door hinge. It is not supported by braces, it is under a bit of stress, and I am welding two different types of metal there (galvanized steel and some other type of steel). Soon as I can I am going to weld the inside of the pipe as well to the door hinge if I can get the welder handle enough in the pipe.
The lower end is kind of a difficult issue. Your drawing and idea is excellent and would no doubt work. (that photo shop program you use looks really efficient by the way) I especially liked the way it took advantage of the bearing bolts to hold it in place, something that I was having trouble figureing out using the pvc. It does use an access panel which I need and is more hydrodynamic. I am not sure how to preceed there yet. I wanted this outboard to be made junkyard style, out of parts that are easy to get with minimal customization. I want it as simple and as easy to fix as possible. If I slap somethig together junkyard style and it meets the minimum 5 mph that I am looking for then I am happy, if not then I will have to make some performance modifications. I have been thinking a bit about the pvc parts and want to try something with them first. Even though I could not find threaded ends,(I did buy a non threaded 4" tee with caps and pipe) I dont think that I would need to glue the end caps in place. The T is desinged to have a pipe go in it then the cap on the pipe. I want to cut a length of pipe like 2" long to mate the T and the cap. I will glue the cap to the pipe for both ends of the T. But where the pipe goes into the T, I will use a seal like your rubber innertube idea. Since I do not have a inner tube avail but do have rubber surgical gloves, I will try to make an o-ring or something like that out of them-if that fails I will buy an innertube and try that. I plan to then grease up the pipe and then hammer the cap/pipe into the T and then test it to see if it is watertight. One question though is if it fits really tight and is watertight great, but will I be able to pull it out again? I have considered drilling a hole in the center of the cap, putting a bolt thru it, sealing it-this would allow me to grab onto it to pull the cap off. The PVC T idea no doubt is not very hydrodynamic, but I think it might be easier for me to put together and if it works great, if not I will use the fiberglass (I have never worked with fiberglass by the way). Looking ahead of these problems, one has been bugging me. How to attach the prop to the 5/8" shaft. Since this is a critical part, I want it to fit nice and straight with no wobbeling. I have even considered having a machinist do this for me but would prefer to do it myself if it can be done adequatley. Its hole is less then 5/8", the guy who sent it suggested that I bore it out to 5/8". I am concerned about boring the hole perfectly straight thru, once that is done, I have to drill a hole thru the prop and shaft that is straight thru..not easy to do these things with a hand drill. Another idea was to put a threaded bolt thru the shaft hole in the prop that fits snug, put a nut at each end of the prop, tighten. Then somehow attach the bolt to the shaft so that it is straight and level-thats the problem, if its even a bit off and the prop shaft is spinning at 2000 or more rpm its going to vibrate and wobble big time. Ideas?
Hmm, lets see here.. about the hindge deal,, How about bolting matching steel to the hindge then weld to your pipe. or perhaps figure a way to get a U-Bolt on it there. One other lesser Idea would be to incorperate some Bunge cords. tied in the middle to yourlower unit shaft, and connected at both ends to the transom of the boat. It will add some stabilization, yet still alow for tilt.
I am a little unclear as to what you described for the PVC pipes but I am aware of the general disign you intend.. I would not greese them in order to hammer them together. try something like soapy water first.. if I am not mistaken, both ABC and PVC do not respond well to hamering, So try to be gentel. I would try to compress it together with Like a car jack, if you can find someplace to prop the jack and the pipe together and get compresion. Now, getting it off again. a bolt mounted and sealed in place might allow you to dissasemble it. I would definitly use as large a washer as possible on the inside.
Dont worry about working with the fiberglass, Its almost like doing paper machea. If you require help on that issue Ill get into it in more detail. Fiberglass is wonderouse stuff.
On too mounting the prop.. I would strongly suggest you mount it exactly the way a standart outboard would mount. Reduce the size of the shaft and thread it with a tap and dye set Drill a hole in the shaft before and after the prop.The hole before the prop is to lock the nut with a cotter pin, the hole after is for the shear pin that will grip the prop. Drilling that shaft could be a problem, But it really is the only accepted way to do that.. as far as reducing the diamerter of the prop. let your motor turn it and put a metal file or grinder to it.( make sure you brace the shaft so it dosent warp ) Using the motor to turn the shaft will insure a even reduction, You will probably have to grind 3 too 4 inches down the length of the prop and then Dye it that far down the shaft. I would drill before I dyed. You definitly do not want to use welding in any way shape or form to mount your prop. I would not drill out the prop. If I am not mistaken ,, your prop should have a rubber bushing inside of it. It best not to mess with it. ow yeah, If you have a choice, use a fine thread dye as oposed to a course thread one. I dont think there is really a junkyard methoid to attach the prop that I would trust. Not if I wanted it to last more then a hour or so. If yo do decide to drill your prop, I dont think drilling it straight is really a concern, the prop already has a hole, and that will asct as a pilot hole and pretty much guide the drill bit in straight. Just take your time and drill slow.
Got a little bit of work done tonight. Had to work late on my job so I will not comment so much tonight. I will probably go with your idea about using a file to reduce the shaft diameter. Does this work well, have you done it?
Updated photos below.
Yes, I have done the shaft reduction in a similure manor. I have used both a file, and a hand power grinder, as well as once with some wet sandpaper when I got down to the end when I just needed a little more.. Getting it to the exact diameter might be a touch tricky but not impossible. DOnt overgrind, remember you need to leave materiel for the threads to be cut into. I would use some scrap wood with a hole in it the size it needs to be and use that for a guide.
Looking at your latest pictures, My only real concern is the shell moving and binding your shaft. Getting all that mounted together solid might be a bit tricky. Im not sure I have any valid sugestions for that. perhaps you can utilize a couple of hose clamps passed through slots on the horizontal pipe obove the waterline to secure it, A bolt or 2 like in my pictured wooden design would also work, But I think you really, ( and I mean really really ) need a secure mount on the botom. I supose the stuffing box is a anchor point, However something is naggin at me saying ya need a bit more. Maybe not,, Like I said,, I usualy design things much stronger then they really need to be.. Probably becuse I am rather hard equipment sometimes hehehe.
I have 3 5/8" rods (shafts) to work with so I will have some room for error with trying to reduce the diameter. Lets say the prop hole is 1/2", do I grind the shaft down to 1/2" then thread it or do I grind it down to a bit above 1/2" then thread. Also, the cotter pins that you mentioned, do these cotter pins go thru the shaft so I will have to drill through it? Lastly, what is that thing that is inside the prop, I can take it out, it looks like it might spin inside of the prop, cant think of what purpose it serves.
Not sure how I will attach the housing. I am hoping bolt middle vertical pipe that goes down to the T directly to the metal inside pipe. Then thread the T to that pipe, once threaded in place it might be stiff enough to hold the lowerend in place without having to anchor it. I will have to assemble the outbourd and look at this to see if it will fit together nicely. If the ABS pipe runs along the upper galvanized pipe, its will would lie flush if it were not for the reducer halfway down. I am thinking that I might use washers at the connection points to make up the the small gap that the reducer creates. I dont know if this arrangement is going to fit or work, just kind of doing it by the seat of pants. I have not been able to get any work done on the project lately and it will probably be a day or two before I can work on it again. I really look forward to the "garbage can" water test to see what happens.
That thing inside, If I am not mistaken, is round chunk of kinda hard rubber. ( at least on the props I have seen ) as far as I understand, it helps absorb shock and allows for it to wobble minutely without comming all apart or vibrating. I believe it is called a bushing. Yes, the shear pin or post behind the prop and the coter poin hole in front both need to be drilled through the shaft. In the back you need a strong Pin, this is what will have to stand up to you torking down the shaft nut
About your grinding to size. I would determin the size bolt that fits through the hole of the prop, then drill your guide to that size. I would make a note of how snugly the bolt fits in the hole, and keep that in mind when checking the shaft. Personaly, I would want the shaft fitting in the guide hole just a smigeon snugger then the bolt does, seams to work for me when I use the dye.
Did not get alot done on actual construction tonight, I went to home depot with the lower end trying to figure out a way to connect the ABS to the steel tube. I am going to try to use a u-bolt at the upper ABS pipe to hold it in place, and then use your idea about taking advantage of the exising bearing bolts to hold the lower end in place. To do that I bought some longer 1/4" bolts that go thru the bearings. I forgot to buy the smaller motor mount bolts while I was there. Maybe I will get by with the bolts that I have although they bind big time. Hopefully being bolted in those two places will be enough to hold the abs in place adequatly. I will have to wait on the prop until I get the rest of this finished, the more I think about attaching that prop correctly the more I worry about it. Updated photos below
I am sure if you use the bearing bolts to secure the ABS in the prescribed manor that it will hold it. I didnt make a special design note but I hope you are intending using many nuts on each beering bolt, 1 or 2 to tighten the bearing to the plate, then other nuts further up the shaft to hold the abs Id probably use 2 to lock them together at the right hight. Might be a bit tricky working in that tight area..
Acared of the prop huh? I wouldnt worry too much about it.Although ita an important thing, It is not a difficult one.. If the shaft is actualy thick enough to bore and tape out to the prop hole size that might be another way to go, However the exsisting method I recomendid I still see as best.
I have to apoligize for the very slow progress of this project. I have had my taxes to do plus the war on CNN plus my lack of know how which have resulted in delays hehe. I have learned a huge amount doing this project though, a little bit about everything,much thanks to your input, if I did it again it would not take nearly as long. Regarding the bearing bolts, I have a bag of nuts and washers to use up so it should be no trouble to use many to hold it in place. I bought some neoprene washers to use to waterproof it, not sure that they will work-I can always caulk it or something. The problem is that the existing 1/4" bolts are too short and the only longer ones I can find are like 5 inches long (I want them threaded from top to bottem-Ihave to keep the 1/2" motor mount bolts because I cant find anything slightly smaller threaded all the way up). I will cut them down with the grinder/saw but I worry that I will be unable to thread a nut on it afterwards. All I was able to do tonight was drill a couple of holes thru the abs to the bearing plates then it occured to me that I will be placing a flat nut head and washer on a round curve, wont be pretty looking. I will be trying to grind the shaft down with a file first but what did you mean about boring out the shaft and and the tape out in your last post? No updated photos, hopefully will get something done tomarrow.
One must work at ones own pace, so dont feel preusured to complete on my or anyone elses account ;p
Personaly, I would use a hacksaw to cut the bolts down to size, then a fine tooth file to smooth it all up pretty like. You can also taper the end of the bolt a little wile cleaning it up with the file, wont hurt anything, and is easy with a large margin for error.
About the flat nut on the round ABS thing. It shouldnt look too bad, I think you will have to resort to RTV silicone or something similure for a seal. If you are really concerned with a flush meeting of nut to abs there you can always cut yourself some custom spacers flat on top for the nut, and slightly curved on bottom for the ABS out of wood or some other available materiel.
On to the taping of the shaft.. Small typo here, that should be TAP not tape hehehe.. I am not sure of the diamerters you are dealing with. But what I was trying to say was If the shaft is suficiently larger then the hole on your prop. You might be able to drill the shaft and tap it out to recieve your bolt through the prop into the shaft. One drawback to using this method, You will not be able to lock the bolt in place, you will be relying solely on 1 bolt without a cotter pin. a locking washer or 2 might help.. it is possible to drill through the shaft & bolt and put a cotter pin in behind the prop but still through the shaft and bolt if this method is employed, But this is not a recomended way, Just an alternate way. Something that would work if it had too. ( if the shaft is big enough. In my experience, as long as you have 1/16th of a inch sidewall after taping, you will be alright, if it is less, the sidewall might giveway under load ). Personly I think reducing the shaft diamerter and using s dye on it is the best method, it allows for you to be able to lock the prop on with a pin. Hmmmm... It occures to me here that you can always tap the hole smaller then the prop hole if need be, and use spacers on the bolt build it up to the prop hole thickness. but as stated, this is not the best way, Just A way. If I have failed to decribe this good enough I can knock you a picture together
I was just sitting here thinking I feel just like my old shop teacher here, He used to present several ways to do something but let us decide which was to be used.
Sidenote here. buddy of mine, also adept in making adatchments. ( no typo there) an Adatchment is a term we coined a few years ago wile creating animitronics for a haunted house. An Adatchment is a part, usualy an handmade custom adapter that connects 2 or more things that dont go together, In order to make them do what You want them too, reguardless of what the parts were originaly designed for.
Anyway, after discusing this prodject with him a few different times as we have progressed here, He is now looking at making a Jet water drive for his rubber raft. That should be a challenge. weight is a real issue in a rubber raft. Im thinking weed eater here as a powerplant, but I am still undecided. Either that or a chain saw. but thats another story. If he persues it this summer Ill start a new thread for its discusion.
Finally got some time to spend on the project but accomplished little other than learning some stuff. After I put the bearing bolts in place with the longer bolts(got to warn you, not a pretty site hehe), the lower T and pipe houseing would not align properly (probably because I did not drill the holes properly alinged-its harder than it looks). Finally I took out my rotozip cutting cool and cut out some of the upper portion of the pipe and an access hole in the lower portion of the T to allow the lower shaft assembly more room to move. The assembly alinged barely ok after that, not nearly as clean as I hoped it would be. I assembled the outboard and started it up and it ran ok without too much belt interference or vibration. But I am overall disapointed with it, its just not as clean and simple as I wanted, I am having to "Macyver" everything now and it is making the project too custom and complicated. My goal was a simple assemly that could be easily replicated again. Starting to lean towards your plywood/figergalss idea but not quite ready to abandon this idea yet. Anyways.. Will have to patch that bottom access hole and upper cut, I think fiberglass might work for that, where do you get that stuff by the way? I have never worked with fiberglass but know of it and the way I envision it is that you lay some type of fabric then paint the fiberglass glue on top? Lol on the adatchments, that is a perfect term for what is gong on here.
I hope that your friend goes ahead with his project and cant wait to see the photos and progress. Update photos below.
hehe yeah your end product is starting to look a little Uhh,, Rough. Pretty standart for a prototype. hehehe
fibergalss can be purchased at any mareine supply store, Walmart, and your better hardware stores. at least around here. Auto parts stores like napa also carry it.Make sure you get resin,hardener and mesh cloth. DO NOT buy tigerhair fiberglass for this.
Here is a quick fiberglssing lesson, at least,, this is how I do it, and My glass jobs have never failed.
A- clean area to be glassed.
B-rough up the area to be glassed with a med to course sandpaper.
C- Lay a clean empty 2 litre plastic bottle on its side and cut a large Oval hole in to serve as a disposable mixing containter.
D- Wear rubber gloves
E Cut your mesh at least 2 inches wider and longer then you need to cover the area.
F-mix resin and hardener in the cut open bottle, drop the cloth in and stire and kneed it til it is fully saturated. ( be fast, speed counts )
G- wrap soaked mesh around the pipe and smooth out as best you can. Speed is more important than neetness. You can always sand for neatness. Try to work neat, but speed is really the key.
H - Let dry a few hours then sand.
Some notes here. Once the mesh is laid, do not peel it back up. You can slide it a little but its best to place it where you need it first shot. It would probably be a good idea to put the piece you cut away back in place before fiberglassing. how much hardener you use determines how fast it will set. too much it will set super fast, Too little and it wont set at all. it is better too use a little more then not enough if unsure when mixing. for your aplication 1 layer should be enough, 2 would be better, 3 should be stronger then the pipe itself. I think after you use fiberglass once, it will become part of your standart bag of construction tricks.
One other note about working with fiberglass, it will produce a certain amount of heat due to the cemical reaction to the hardener. this is normal, and sometimes feels very warm, but not enough to burn you.
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