air+dried+beech Wanted - Air Dried Beech

[AndyMiller]

Hi Everyone

 

I am looking for 45 to 50 mm thick air dried beech to make cog teeth, for a gear in a watermill in Herefordshire, see phot attached

The cogs are made out of 115mm x 115 mm blocks that need to clean wood with no shakes, knots, spalting or sap wood.

The grain needs to straight maximum 45 degrees, cogs with cross grain grater than this are liable to split. (see diagram attached below)

I total in need make 170 cogs or 20 meters of usable wood.

 

The cogs look like this:-

 

[trigger_andy]

Hey Andy. I have some 3-4 year air dried Beech available but due to being away for the next 2-3 weeks and being in Scotland I’ll assume you’ll find something closer.

Curious why you prefer/need plain sawn and that quarter sawn is the worst of the bunch?

[AndyMiller]

Hi Tiger Andy

Thanks for replying, 3-4 year old is good the older the better, but your right Scotland is rather a long way, how far north in Scotland are you.

The grain direction is to do with the cog withstanding unexpected impacts better when something accidently dropped into the gearing break a cog.  Once on cog breaks several other will follow and even possibly damage the casting.

[trigger_andy]

Hi Tiger Andy
Thanks for replying, 3-4 year old is good the older the better, but your right Scotland is rather a long way, how far north in Scotland are you.
The grain direction is to do with the cog withstanding unexpected impacts better when something accidently dropped into the gearing break a cog.  Once on cog breaks several other will follow and even possibly damage the casting.

I’m North East Scotland, just outside Forfar.

Interesting points regarding the cogs. As I understand it quarter sawn like the bottom picture is the most stable but the top plain sawn I guess with the more cross section of the grain the cogs are stronger?

[AndyMiller]

16 minutes ago, trigger_andy said:

 

I’m North East Scotland, just outside Forfar.

Interesting points regarding the cogs. As I understand it quarter sawn like the bottom picture is the most stable but the top plain sawn I guess with the more cross section of the grain the cogs are stronger?

 

Forfar is a long way for me 11hours too old for all night driving . If the cogs are operating correctly they smoothly mesh in and out share the load with the adjacent cogs.  The problems arise when there is a shock load by a foreign body or broken cog. Quarter swan wood will split along the grain then they will start work loose and that when then trouble starts.

[trigger_andy]

2 minutes ago, AndyMiller said:

Forfar is a long way for me 11hours too old for all night driving . If the cogs are operating correctly they smoothly mesh in and out share the load with the adjacent cogs.  The problems arise when there is a shock load by a foreign body or broken cog. Quarter swan wood will split along the grain then they will start work loose and that when then trouble starts.

Love the mill though, any more pictures? 

 

Ive toured a few Rum Distilleries in the Caribbean and always take the time to marvel at the engineering thats gone into these old Mills. 

[topchippyles]

5 minutes ago, AndyMiller said:

Forfar is a long way for me 11hours too old for all night driving . If the cogs are operating correctly they smoothly mesh in and out share the load with the adjacent cogs.  The problems arise when there is a shock load by a foreign body or broken cog. Quarter swan wood will split along the grain then they will start work loose and that when then trouble starts.

Gavin may have some down at wentwood timber 

[Stubby]

To be known from this day forth as TIGER ANDY ,....GRRRR😁

Edited April 9, 2021 by Stubby