Central heating. Death to nice wood. I have had central heating for the first time in my life these last 2 years and my china cabinet, which my Grandad made in the late 1920s has a crack you can pass a match through in the bow top. Grandad would be furious! But I've cut a diagonal in pear and forced it in under the smaller roof and that's sorted that one and the larger roof is already repaired in three corners with the fourth tomorrow. Already getting the slight droop out of the bigger one and glued with epoxy. I was delighted to find the square connector of the Taycol coupling still there along with the original Mersey Marine bow fender. Also the speed controller of my Proxxon drill, which went home very soon after I got the drill, so I ripped it out and wired straight through, so it's been flat out ever since! I wouldn't be without it though! I shall be pressing my epoxy into use to coat the ply both sides, using an old credit card to press it into the grain. Then this 54 year old baby will be good for another 54. Cheers, Martin
Now the Chine rubbing strakes are fitted, dry and filled and I have attended to the minor lumps and bumps the next job is to give another coat of resin, taking the issues of the first application into account I intend to apply a thin coat, this has the effect of filling in the pattern of the glass cloth. Another two days have passed and it’s time to do some rubbing down. I have found that the surface is very hard, more so than I recall some of the other fibre glass projects I have done but these have been using Polyester resin. It’s a first for epoxy, so is epoxy a better choice than Polyester? According to my mini research – Epoxy is more versatile Epoxy has fewer fumes Epoxy is stronger Epoxy shrinks less Conclusion Epoxy is the better choice for repairing/covering either wooden hulls or repairing fiberglass boats. It has excellent adhesive qualities, wets out fiberglass fabrics and it is tough. It has great thin film cure characteristics, cures in cool temperatures. After the first coat I wasn’t 100 % happy with the finish but I just thought that some dust had landed on the surface before the resin had dried, (this was proved not to be dust but because of the matting pattern still been visible it disguised the real problem) however this was easily sanded out with wet & dry. Now the hull and deck were looking really smooth with very little sign of the matting pattern it was time to give a final coat. I had decided to coat both the deck and the hull in one go so I mixed enough resin to do the lot. Starting with the deck I started to apply the resin but to may horror it started to pin prick all over the deck surface, panic, panic what was causing this? So was it the brush which I had previously washed out with cellulose thinners after applying the last batch of resin. I decided to remove the resin and use a new brush (I had 90 mins cure time to do this) so cleaning of with paper towel and finally with a wipe with thinners I started to apply resin again – but it happened again as I sat in despair I looked into the pot of resin wondering where to go next when I saw a film on the top of the remaining resin It was then I noticed a ridge in the cups side. It was the wax coating that had melted into the resin and subsequently appeared as pin pricks in the newly applied surface. At this realisation I removed all the resin again and took a breather hoping I had found the problem. Another day and a light rub down of the deck to make sure the surface is ready to receive its final coat. Resin weighed (in a glass container this time) and well mixed I started to apply again and fortunately it was OK and all surfaces were coated.
As the hull glass matting is really dry and has had some minor filling done it’s time to fit the chine rubbing strakes. which have been in the jig now for some days and consisted of a two dimensional curvature jig. In order to make sure the strakes were equally balanced on each side I made a cardboard template that followed the Chine stringers line and rested on the Gunwhale rubbing strakes, having drawn a line on the port side I flipped the template over and drew a line on the starboard side giving a perfectly equal curve on each side So now to prepare them for fitting. The jig had made a curve that was a really good fit without much spring. I decided to use some very small brass pins (0.5dia x 10mm long) to hold them whilst the epoxy sets. I pre drilled the whole length of the strake and lightly inserted pins along its length, then applied the epoxy and started to fix from the bow and followed the pencil line back to the stern. This was repeated on the other side, when set there was some minor filling to be done/filling pin holes.
Having used spring bronze, (Thanks Derek) I wish now I had used brass & silver soldered the joints. I will have to epoxy the floats in place now. Don't want them to melt the rest. Can't say I altered the plan because there isn't one. But I dished the inner wheel more than the outer in the end.
Gunwhale rubbing strakes As these pieces will be under stress they need to be steamed into shape prior to fitting so out with the wallpaper stripper and modified tube (1/4 BSP fitting in the bottom of an old piece of IKEA cloths rail).For the gunwhale strakes I used the same former as I used for the stringers so 20 mins in the steamer then into the jig for 2 days drying. The chine rubbing strakes will need a different jig but this time a left and right hand version as not only do they bend round but also up at the bow. I was however disappointed with the quality of the 3/16 square obeche as the grain was nearly at 45 degrees to its length – it snapped before I started to bend it, just pushing it into the jig I bought some better pieces from the local model shop. I temporally fitted the gunwhale rubbing strake slightly proud of the deck level in order to drill all the pin holes then remove and mix up some epoxy, coat the length and hook into the brass bow and start tapping in the pins along the length of the boat, repeat on the port side. Chine rubbing strakes are still in the jig!
Before I do the final coats of epoxy the rubbing stakes need to be fitted but then Robbob pointed out the vulnerability of the bow particularly when transporting through doorways. I decided to take that advice and make a brass bow bumper, this will not be visible when finished but will stop any structural damage if the bow is hit, it was screwed and epoxied in position. The design also incorporates a location for the rubbing strakes holding them in position when fitting. Thanks Robbob
Right chaps, firstly many thanks for your suggestions. I won't be doing LiPos, because the charging is too complicated for me. I can't read the instructions of my fancy charger so it remains in its box. I forgot that I can get NiMhs in sealed packs, so that'll be something I get hold of, although the shop had more out of stock than in! Secretary, I liked the look of that servo you linked me to and will be getting one. Norman, I have today picked up my Spektrum DX5e from my daughter's place where it was in store. I found it whilst looking for something else as always! I already have the Orange Rx and can now try binding it, when I have some batteries for both items. I also have 27meg gear, three different lots and WILL be using it in my classic speedboat models. I waste as little as possible! I have now settled on a continuous loop for the sail control, which doesn't need spring tension, though haven't decided a good way to attach the sheets to the loop or how to tell when the loop has gone as far as it dare before getting a bit mixed up. But I have sorted out the plank system by making one section trap a second, both of which can be removed separately. I found a gear and shaft out of an old printer which I chucked in the lathe and turned a groove in for the loop line. Then I found a use finally for that 6mm ball race I've had in my drill drawer for years! It was an interference fit on the shaft. I had some PTFE plate for another task and in some spare I made a hole that the ball race pushes into a treat, below it an identical plate supports the other end of the shaft, PTFE being very low friction. All this levels the return "pulley" with the servo drum. I only have a limited length of run for the loop line, but it should be enough. It's all I got anyway. About 10" between pulley and drum centres. If I attach the sheet part way down the boom instead of the end I should have enough movement. So, progress. My son-in-law supplied some bike gear cable for the rudder actuation as the rudder stock is at an extreme, typically cutter, angle. A hunt through the supplies (Pringles tins) gave up enough aluminium tube to guide the cable. Alas, I installed with lots of epoxy the rudder tube and it turns out to be 4.5mm bore! Gawd knows where that came from. The tube built into the back of the rudder itself is 4 mm. So that'll be some lathe work ahead. All good fun between the gardening chores. Cheers, Martin
Hi all, a 1/16th scale model of the boat I used to live on at Burnham-on-Crouch. 1/8th" Cuban (yes really!) mahogany from 1920s chairs made by my cabinet maker Grandfather. Covered in J cloth and epoxy. J-cloth is very compliant, but yet very strong when soaked in epoxy (WEST System). Lightweight fillered for the bits where the saw wasn't as accurate ripping the strips as it might have been. Black enamel primer.
Get yourself a small pack of epoxy resin from ebay and seek out all slight delaminations of the plywood frames. Get the epoxy in those split bits and clamp them up. A clothes peg is sufficient if you're short of space. You can put a piece of cling film twixt peg and wood so the peg doesn't stick. Then use the rest of the epoxy to waterproof the insides. Be thorough and methodical. If you sand the model back to wood, use epoxy on that, either through fine model aircraft fibreglass cloth or just squeegee epoxy on all over with an old credit card. It goes much further and gets forced into the grain. It's not necessary to use GRP cloth on everything if it's well built. I have several over-50 year old model boats that are perfectly water tight with decent paint jobs (enamel, of course). Cheers, Martin
I purchased as recommended by Robbob the fibreglass package which consisted of 750g of epoxy resin and 250g of hardener, I also went for the 90min cure as this is the first time I have ever done a boat hull, I’ve done plenty of stranded fibre cowlings/air intakes etc. where you lay a gel coat first then stranded matting which is so different to laying a fine matt on its own. I also ordered some mixing sticks and throw away brushes. First I cut the matting to the slightly oversize for one of the side skins, then loosely taped the matt to the bottom skin and checked the coverage - and checked again then fold over to the opposite side, this then leaves the surface clear to apply the resin. Mixing the resin should be done accurately, so borrow the kitchen scales and here we go. I wasn’t sure how much to mix for a side skin but 25g of resin and 7.5g of hardener looks about right. So mix well and then brush onto the side skin, then I gently lifted over the matting and laid it on the skin and gently brushed the matting down, the matting is almost sucked onto the resin so minimal brushing is required to ensure a smooth surface A previous blog said that “Less is More” how true this is, the temptation to spread the remainder of the resin on to the already adhered matt is something to be avoided, however learn by my mistake as I did just that (only in a small area on one skin) leaving rather a lot of sanding later after the resin had fully cured as it leaves a rather lumpy surface. So onward and upwards the following three surfaces were relatively easy with only minor difficulty keeping the matting in close to the 90 degree angle between the keel and skin and I had to keep going back to it pressing it in with a steel rule until the resin started to go off but minimal resin left a surface that was flat and the weave of the glass matt can be clearly seen and felt but minimal sanding is required if at all. Then a further 2 coats of resin with sanding in between will leave a smooth surface ready for final preparation of painting. The final picture is of the roof that in a previous page I said to add strength the roof would need a coat of glass to reinforce the unsupported edges – To be continued
Ah, cellulose, of blessed memory. I still have some, come to think of it, but forgetfully, I bought black gloss enamel for Vanity and some enamel primer for it also in black First coat on today. But I will definitely experiment with spraying the final coats. I sprayed an old pre-War Marblehead with enamel and it went on well. You can still get cellulose if you can convince the dealer it's for your classic car. My son has a 1951 Renown so I could always quote all IT'S details to get it, but I don't think they'll post it and I'm nowhere near any suppliers geographically. I couldn't see the point in paying for epoxy tissue so I bought a huge bag of J cloths from Poundland and used that with epoxy. Slarred the epoxy on the mahogany hull (made from old chair legs my Grandad had made a dining suite with) and then laid the J-cloth on the tacky epoxy and slarred more on with an old credit card. All my credit cards are old now and a damned site more useful as epoxy squeegees than they ever were before. Got a few ridges where they overlapped, but filler sorted that out. The hull is still very light, so will need all the large lead weights on the end of a long fin keel (removable) as it carries a big rig, (see avatar). Good luck, Martin
Hi jbrcfloats and welcome to the mad house. Yes you are correct in saying that epoxy gives of heat while it cures and can cause damage to some of the more flimsy plastic hulls. The best way to be save when using epoxy with these hulls is to use smaller amounts so not to build up to much heat.
Hi, Great build. I'm in the process of building a Mid West Tug Boat and reached the point of needing to place some ballast in the bottom of the hull. I noticed that you used epoxy. I know that epoxy can get hot when curing and if you using a molded hull how do you control the heat issue so as to not warp the hull? I plan on using shot gun shot and been a bit worried about damaging the hull.😁