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Post by Shipshape on Jul 23, 2014 9:20:58 GMT
The builders here at the Bristol boat would be interested in any input on creating tapered holes for the thole pins . By the time we have finished the gunwhales and put the tholes in place we will have about 70mm of oak to drill into. Advice I recieved at Portsoy was that a tapered hole was essential to stop the pins jamming permanently. I didn't think to ask at the time how this was achieved.
I am aware that chairmakers often make their own tapered reamer and was proposing to do this. I assume that the hole is then drilled progressively deeper with decreasing diameter drills and then reamed out.
The degree of taper must be critical to theretention of the pins so would welcome any advice on this or how to create the holes. We will turn our own pins.
Thanks to all those skiffies at Portsoy who allowed their boats to be repeatedly photographed and answered patiently many questions.
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Post by Gareth on Jul 25, 2014 21:26:20 GMT
Boatie Blest use pins of a fairly small diameter, using a very hard timber. Neither the holes nor the pins are tapered although we did toy with the idea of turning the pins with a slight taper. The timber we use does swell very slightly and it has to be well oiled but we haven't (yet) got one stuck. There is however a lot of judicial use of the mallet. A tight fit is essential as any movement will soon cause wear and the pin will work loose. The whole wooden pin thing came about with us after we were banned from using metal pins and was really intended as a stop-gap until something better came along. But it hasn't. So until we manage to work out how to create a threaded wooden pin and wooden nut to go with it or somebody comes up with a better solution we will stick with the straight pins. Good luck!
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Post by seanie on Jul 25, 2014 21:30:16 GMT
Having gone through various combinations of pins, kabes etc., including tapered removeable pins through routh/gunwale, I wouldn't recommend removeable pins whatever version your going for. I'd go for pins glued into a routh.
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Post by Admin on Jul 25, 2014 21:45:33 GMT
Hi Shipshape. A couple of clubs have tried thole pins to my knowledge, Portobello and North Berwick, but most have gravitated toward a single pin system using a simple drilled wooden receiver plate on the oar, or a more complicated wooden rowlock system as in North Berwick's latest system or Ullapool's well established system. I imagine this is because with a limited open development class as the St Ayles Thole pins have been found wanting, whereas in Cornish Gig rowing they are part of the one design and provide a level if not optimal playing field. A number of boats I have seen recently built have twin Kabes or rectangular pins which fulfill the same purpose possibly less efficiently than thole pins, but most competitive boats are using better systems. A single pin reduces slack, gives maximum arc and needs no attention from the crew to the angle of the blade or gearing. However I am sure there are still some crew from Portobello who look back on their days of feathering and the distinctive clank of their oars with fondness. I have punted your question over to the St Ayles Facebook page so you may get more replies, I am intrigued myself as to how to make a good tapered receiving hole for pins, I have seen tapered reamers for sale but they are generally of too steep an angle to be of any use for this purpose.
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max
New Member
WSV Woudrichem @ www.wsv-roeien.nl
Posts: 3
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Post by max on Jul 26, 2014 6:48:08 GMT
We at Woudrichem have been a laughing stock with our 'shark-fin'-style oarlock system and wanted to upgrade to the much simpler thole pin. It has been a challenge of indeed creating the tapered hole, but we managed by making a conical drill ouraelves ( much cheaper then the commercial things available ). We first drill a hole 22 mm into the block at the gunwhale and subsequently ream this with the reamer, a 3 min job. Have a look at our website for a video of this and I can post an image of the reamer for a more detailed view, www.wsv-roeien.nl/ct-menu-item-11/groot-grut-2Happy reaming!
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max
New Member
WSV Woudrichem @ www.wsv-roeien.nl
Posts: 3
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Post by max on Jul 26, 2014 7:58:59 GMT
Here a picture of the reamer Sent from my iPhone using Tapatalk Attachments:
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Post by David Kirby on Jul 26, 2014 9:59:20 GMT
Stepped drill bits may help, these are cheaper than taper then clean out with 60 grit around a tapered dowel. Or approach the problem in a different way and turn a hole in a square blank to insert into gunwale, these can be of a contrasting harder timber and can be replaced. You can if needed get tapered Oak Pins fairly easily.
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Post by topher dawson on Jul 26, 2014 10:26:41 GMT
Hi all,
In Ullapool we have hardwood pins parallel 28mm diameter above the gunwale and 5 degree taper, that is 2.5 degrees either side of central, on the bit which goes in the gunwale. We made a taper reamer with a bit of saw blade ground to the taper inserted in a sawcut in a wooden body which we turned in a parallel hole. But in the end the pins became loose so we found a much better way which is, you make the pin tapered, wrap it carefully in one layer of brown parcel tape, and put it in an oversize hole with a lot of epoxy. You need tape under the hole to stop the epoxy drooling out.
Makes a really accurate strong hole, seals the wood in the gunwale, no machining needed. The pins always come out with a couple of blows of the hand, don't rattle, don't need a mallet.
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Post by R Brown on Jul 27, 2014 13:34:11 GMT
Hi, we've built our second skiff in Wick and like you wrestled with the problem of tapered holes. We started with a series of stepped holes and then made a wooden reamer with three slots into which we slid junior hacksaw blades. It worked but clogged up quickly so we shaved off the wood in front of the blades to allow a little room for dust build up. That got us our first boat up and running. On the second boat Geordie, our "all things metal" expert made a steel reamer, again with three cutting edges,which worked much better and faster. The combined angle of the taper was 5 degrees (2.5 either side of centre line) which was as near to a morse taper as we could get without running into major problems. You might be able to reduce this angle if you worked with narrower pins. Ours start of at 38mm which is perhaps a bit "belt and braces" but we decided to stick with it to keep both boats the same. The critical thing for us was that we didn't want the pins to stick out at too big an angle and so we made up a jig to bore the original holes so that the taper would in effect run down the inside face of the top plywood stroke or board. You could argue all day if this is technically correct or not but cosmetically we thought that if the pins are bored at right angles to the top of the gun'l they didn't look so good. We wasted a lot of time boring our first boat by giving the reamer far too much to do. It doesn't really matter if , halfway down, the hole is slightly oversize. And to finish off and make sure the holes fitted well we wrapped our pins in clear food wrapping, "clarted," as we say in Scotland, the sides of the holes with a mix of slightly thickened epoxy and then pushed in the pins. The result was a very good tight fit. We,ve now added a final touch to our new ones by drilling a hole in the pins, just where they clear the underside of the gun'l and fitting a wooden retaining wedge.
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Post by frank wood on Jul 27, 2014 19:16:41 GMT
I made a reamer out of an old file , just ground the edges enough to make them cut . The files taper looked about right to me and we have had no problems with them North Queensferry boats
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Post by shipshape on Jul 28, 2014 8:56:19 GMT
Many thanks for all the information. lots of food for thought to digest. Will report back at some stage on which solution we opt for and its success or otherwise.
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AP
New Member
I should never have listened to Mark Irvine
Posts: 39
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Post by AP on Jul 28, 2014 9:14:13 GMT
We use 38mm oak pins, glued in place. They are on their 3rd season of hard use and will last at least another season, then we will cut them off, drill out and replace. They will never break and wear slowly so no need to make them removable.
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Post by wkskiffer on Aug 3, 2015 20:31:00 GMT
One reason we decided to make them removable on our boats in Wick was that when man handling the boat they were the first thing that people took a hold of and we were concerned that there was potential to split the gunwale if enough lateral pressure was applied.
Looking back, is it more trouble than it is worth?
Well it looks fancy but is probable not worth the trouble..
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