November Saturday 14th meeting will be a club day. As usual please bring any problems with woodturning to the members who may be able to help or advise.
If you have not paid for your Carvery with Paul or made your menu selection known to Fred, please do so as the Carvery is on the 22nd Sunday and the tudor rose need confirmation a week before.
Greg Moreton returned to the club for the October demonstration. Greg started turning around 30 years ago and is a well known and accomplished turner. He started the days demonstration with a wet blank cut from an Ash log to create a bowl. The purpose of this piece was to take the members through the process of rough turning, drying and ultimately finishing a piece turned from Green wood.
Starting with a screw chuck and tailstock support, Greg found the centres and then started turning at a low speed until the wood became more balanced and the speed could be increased.
A chucking point was created on blank, ensuring that the centre was well marked for future re-turning once the piece had dried and was mis-shaped. The basic shape of the outside of the bowl is cut to the rough shape, but you don’t need to focus on the final form, although smooth cuts are best to help the wood dry evenly.
The blank is then reversed onto the chucking point to begin rough hollowing, Greg explained that when mounting wood, particularly wet wood, it’s best to hold it in the chuck by pressing in the centre rather than around the rim before tightening. This ensures that the wood is centred in the chuck before it is tightened. As we’re turning wet wood, it’s important to check the chuck for tightness from time to time because wet wood shrinks as it dried. Greg uses a 40/40 straight across Grind on most of his gouges with the bottom of the bevel removed to help[ reduce the heel of the tool compressing the wood during it’s traverse across the work. Once the sides have been turned down, Greg uses a much shorter grind to work across the bottom of the bowl to avoid fouling the side and ruining the rim of the bowl.
Once the rough turning was complete, Greg showed how he seals just the end grain of the bowl blank using End Seal from Chestnut. This ensures that the bowl drives more evenly by stopping the evaporation of loose water from the end grain whilst allowing the side grain to breathe.
The next piece was a natural edge bowl from a log of Tulip wood. This started with a split tulip wood blank, which Greg had rounded the ends on the bandsaw to save time. Starting between centres to being shaping and to create the chucking point, Greg showed how he uses a ring centre to reduce the risk of the standard live centre driving itself into the wood and splitting the blank.
As he started to shape the bowl, Greg showed how he cuts against the grain onto the natural edge. Doing this ensures that the natural edge doesn’t get pulled off by the gouge motion and provides more chance of the natural edge remaining on the bowl. Once the edge is defined and set, the bowl can be cut with the grain in the normal manner, up to the set edge. Greg began to shape the bowl, aiming for a tulip shape on the outside.
Now turned and mounted in the chuck the centre is removed to a rough finish, ensuring that the wings are set before removing the weight of the bowl. Once complete this is then sealed in the same manner as the previous bowl before leaving to dry for 5-6 months. These bowls are typically stored upside down in a stack to allow airflow. By drying upside down it prevents the moisture being trapped in the centre of the bowl.
Once dry, a drive pad made from a wood blank and neoprene or similar material is used to re-centre the blank and allow the chucking point to be re-cut before tidying the outside of the bowl and then sanding to a finish. Greg does this using a 3 inch sanding disc, with the lathe stationary to protect the edges of the bowl once he needs to work on the natural edge.
Once complete, the piece is mounted in the chuck and the centre of the bowl re-cut to an even balanced shape before the finishing cuts are made. If the bark comes off during this process, it is best to remove it rather than try and glue it back, as glue is never as strong as the cambion layer for this purpose.
Again the piece is sanded with a 3 inch disc on a soft pad, sanding stationary when doing the wings to protect the natural edge. This would then be finished using 3 coats of Danish oil, with 24 hours in between each coat.
Once oiled, the spigot is then removed using very small cuts to avoid catches before sanding away the final remains and finishing to the same standard.
The afternoon piece started using very dry Oilve Wood to create a pepper grinder, however this piece proved to dry for what Greg needed, so he switched to a walnut blank. The intent ion was to create a Pepper Grinder to match his existing one.
The base was mounted roughly in the chuck and the main body hole was drilled 16mm deep to a diameter of 38mm. The body is then reversed so that the bottom holes can be cut. Greg highlighted the importance of flattening the face before drilling.
The first hole is 45mm drilled to a depth of 19mm, then 38mm to a depth of 53mm. Once this is completed, the centre is drilled all of the way through the blank until it meets the other hole. This was drilled using a 25mm awl bit.
Once completed, the notch was cut at the back of the 38mm section for the pepper grinder lugs to be seated in. This was a home made tool from an old chisel, cut carefully so that only the Lug blade that cuts the recess was sharpened with the rest of the blade rounded to prevent opening up the 38mm hole.
The blank is then mounted on carefully cut jam chucks inserted into the drilled holes. This ensures that the pepper mill body is centred carefully around the drilled holes. The design is then laid out on the body and the basic shape cut to a finish. Sanding was done through the grits to 320 grit before finishing with sanding sealer thinned to 50/50 to seal the wood.
The body was removed and then the top blank mounted so that the top of the top could be levelled so that it sits flat in the chuck. This was then reversed in the chuck so that the recess in the bottom of the top could be drilled. This was trimmed flat before a 22mm hole was drilled to accept the drive centre from the pepper Mill kit. This hole needs to be 40mm deep with a slight hole in the centre of this hole to receive the drive rod if the body is slightly too short.
A recess is then formed using the same tool as before to accept the lugs from the drive piece. The top is then sized to match the base, ensuring that the top rotates smoothly on the body with a 38 mm spigot to match the 38mm hole. A bead was formed to match the body and to disguise the join.
The top is then reversed onto a jam chuck to centre on the hole before the top can be finished. The mechanism is then fitted and the grinder assembled. If the drive rod is still slightly too long and the top doesn’t sit all the way down, the rod can be trimmed using a Dremel with a metal cutting dish.
The final piece of the day was an offset Bud vase out of Yew. This was mounted well out of true between centres, before forming a chucking point on the bottom. This is then mounted in the chuck and the top is shaped to resemble a lily shaped flower on the top of the vase. Speed helps here due to the amount of negative space whilst cutting the out of true blank, and a white sheet of paper laid on the lathe bed helps to make the ‘ghost’ more visible during turning.
The centre is then drilled out using a 3/8” spindle gouge whilst the opening is then widened using a bowl gouge. The body pof the leaf shape is then sanded before the rest of the shaping is done. The body is formed, aiming for a thin wall thickness on the stem of the bud vase. Cuts are made carefully working towards the headstock to reduce vibration. A bulb shaped base is formed before sanding and then parting from the lathe.
Paul/Fred
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