[Public-List] track car slides

[Don Campbell]

As always, choose your wood carefully for the job at hand and really 
look for the piece that won't splinter . I suggest the variety of teak 
or oak will make a difference as well. (It won't be cheap, either!) The 
thing is that there is a great amount of stress and strain on the track 
bases and they move or at least flex with these forces. Not only is 
there the lift from the sheet in the block (at more than 100% of the 
load), but also there is  the torque or resolved force from the sheeting 
angle from outboard that occurs on any point of sail more than close 
hauled.
    Generally, the best material that we have to go back to its original 
shape is wood. Life with boats is always a compromise and choices need 
to be well thought out. If you torque the fasteners in the original 
installation so that the wood is distressed to begin with, you have 
already increased the probability of splitting and splintering without 
any of the intended load applications being applied. Backing plates and 
balancing of these forces matter in places like these.
    Once again, I suggest that your research include work by the Gougeon 
Brothers as they have been at the fore of maximizing the combining of  
old and new technologies  and  for using testing methods to determine 
strength and breaking strengths that show results in real numbers.
Don

George Dinwiddie wrote:
> Don Campbell wrote:
>   
>> Seems tome there is one thing missed here. If the original product used 
>> lasted for 44 years, then if you use the same product equally well, it 
>> just might last for another 44 years and that is not a bad track record. 
>> The newer caulking materials might outlast the old as well and if you 
>> are still sailing this boat in 44 years, then more power to you.
>>     
>
> Don, in many cases the original product (talking here about the teak 
> strip under the flat track on the older boats) did /not/ last.  I've 
> known boats to sail for decades with bits of teak splintering out from 
> under, and with spots where the track car hangs up.  So, while I 
> generally agree with the sentiment of what you said, for this one 
> application I generally think that replacing with plastic is a better 
> choice--cheaper and more durable with no loss of functionality or looks.
>
> That said, if you've got a strip of teak, there's no harm in using it.
>
>   - George
>
>   

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