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#34229 - 08/16/17 09:19 PM Re: historic hewing questionnaire ***** [Re: northern hewer]
northern hewer Offline
Member

Registered: 03/17/02
Posts: 1098
hello everyone tonight

Its been a while sorry-----but lets try and continue a little further--

You know, this old crude mill is pretty interesting, don't you think?, even now as I ponder its intricate parts, it seems even more complicated than when I operated and maintained it--

Well we were talking about the moveable bunk lets continue--

Now we have a general idea about its shape there is one more important aspect, which is the replaceable inserts, on the upper leading edge of the bunk, on which the log to be sawn will rest.

There are 2 of them one on each side of the slot, they are in dimension 4 by 6 inches, bolted and well secured in position, their position being approx. 1.5" apart

These inserts are cut into the upper surface of the bunk allowing enough depth to accommodate wedges for levelling their upper surfaces

Now I say levelling well that is misleading, because a good millwright will understand that under the weight of the log, when one is eventually loaded, the bunk will deflect down slightly, causing a vertical cutting error, so to compensate one must slightly elevate the end of the insert closest to the blade

To facilitate this measurement of squareness pull the moveable bunk ahead until it is abreast of the vertical blade and is situated between the two replaceable inserts

Now placing a square against the blade and on top of the insert, one should observe that the top of the insert is out of level slightly by about 1/8" on the 24" blade of the square

Now this will work for most ordinary logs, but might not be enough for very heavy logs that may cause more deflection in the bunk

well have to go for now

enjoy--like to hear some comments if you are enjoying--

NH

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#34230 - 08/17/17 09:13 PM Re: historic hewing questionnaire [Re: northern hewer]
northern hewer Offline
Member

Registered: 03/17/02
Posts: 1098
hello everyone tonight

To round out a complete picture of this bunk, ready to work will consist of the hardware items, that are quite massive and heavy--2 separate cast iron dogs, that are fastened to the moveable bunk, on each side of the slot in the bunk, so that they can be hammered into the end of the log with a wooden commander--the dogs are not easy to describe but I will try--they are shaped in a mirror image of each other--each one shaped like an upside down "u"--the "u", with a spur on the leading top edge closest to the blade--this spur is 2" in height and 1\2" thick of steel and sharpened along its full length using one bevel, the "u" is about 14" in height, with a spread of its legs about 10", and constructed using 1.5" wrought iron stock in the 1800's by a good blacksmith.

The bottom of each leg has an eye with an associated eye and bolt intertwined together for fastening to the bunk, here again there is usually not a thread and nut but rather a slot with a tapered key fashioned into the end of the bolt

Well have to go now

hope you are enjoying
any questions just ask
NH---Richard Casselman UE
14572


Edited by northern hewer (08/17/17 09:16 PM)

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