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ULLAPOOL WOODTURNING CENTRE. |
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F.A.Q.s. |
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Tel/Fax...01854 655334 |
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F.A.Q.s. Frequently Asked Questions |
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Above, Fire Screen. Made in Mahogany, With a glass front. Customers own Tapestry. By Alec Mutch. For more details and enlargement, Click image. |
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Above, a very elegant carving of an abstract bird form. Made in lime. By Stephen Hayward. |
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Above, a jewellery stand, Made in beech, By Alec Mutch. |
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Question (1) From, Mr R Sutherland, Inverness, Scotland. What type of glue is best suited for making laminated bowls, and also for making laminated tops for tables, furniture etc. Answer (1) The type of glue we use for this needs to be one where movement after completion is practically non existent, or at least kept to an absolute minimum. For this we recommend Extramite or Resintite, Both are mineral glues that are simply mixed with water to a smooth paste. Extramite has a slightly longer working period, (by that I mean the time it stays active whilst applying, before it starts to set). This is useful when you have multiple assemblies to do at the same time. Resintite also works well, but with a shorter working time, so use this when fewer joints are being glued. What about P.V.A. I hear you ask? (Poly Vinyl Adhesive) by its mere description Poly Vinyl, means its flexible, and can move after use, not a good thing in a laminated bowl or table top, however its very useful in all sorts of other joints, such as chair legs, table legs and all sorts of carcase joints where a little movement is less critical. See insert pictures (left) and click the link to our Glues page. This reply was compiled by Alec Mutch, on behalf of A & R MUTCH (Woodcrafts). |
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Click either picture Above & below For our glues page. |
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Question (2) From, Mr P Byrne, Inverness, Scotland. Hi Alec, hope you dont mind me asking your advice again with regard to the PEG solution ? Im wanting to try out a style of vase using green hardwoods (12 high x 4 dia. at base) to hold fresh flowers. So far have been unable to find suitable 8 high glass inserts, and Im wondering if the PEG was poured into the hollowed out area would this form a permanent barrier to hold the water inside. Answer (2). Your idea with the PEG (Polyethylene Glycol) may not work, its main use is to stabilize wet or green timber whereby it merely replaces the moisture in the wood, with a polymer by a process known as osmosis, but this alone will not be enough to hold water, I dont think. What you would also need is a product called Rustins Plastic Coating, but this may also be a bit hit and miss because of the width and depth of the holes, i.e. difficult to see what you have actually done, and you may not cover everywhere, and you need to cover everywhere. Far better to use a liner, you mentioned that you could not find anything suitable, well we stock a range of these liners in our shop, the measure from 190mm high to 287mm high, with a diameter ranging from 37mm to 97mm. See inset picture, (left) and click the link to our Sundries page. If you do decide to use a liner, remember to drill the hole approx 6mm bigger in diameter than the insert, this will allow for contraction in the wood, all holes drilled into wood shrink, remember that, if not you will crush the glass. This reply was compiled by Alec Mutch on behalf of A & R MUTCH (Woodcrafts). If anyone reading this has actually tried sealing wood with PEG in order to hold water, successfully, please let us know, we would all be very interested. Please use the link below, we will publish your findings.
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Question 3. From, Mr P Byrne, Inverness, Scotland. Have just finished turning two wine goblets in walnut and I bought a tin of Chestnut Ltd Food Safe Finish oil to coat onto the goblets, Sent an e-mail to them to check if it was suitable to use on the goblets. Their reply was Not Advisedleave the wood untreated Try and use a much denser timber. Would Oak or Cherry be suitable to make goblets for drinking from? Answer 3. Your wine goblets that you want to be useable, i.e. drink from them! Whilst your Food Safe Finish oil may be ok for most things like salad bowls, servers etc, its not suitable for liquids because it does not seal to a waterproof finish. The advice you were given via Chestnut Ltd, to use a denser timber, is on the whole good advice, provided you know what timber is denser than another? You ask if Oak or Cherry may be more suitable? The Oak is a definite no no, it contains some toxic acids, namely tannic acid. As for the Cherry it is no more dense than the Walnut you have at present, Walnut having an SG (Specific Gravity) of .64 and Cherry an SG of .61. What you would be looking for is a timber with an SG of .80 or above, 3, that fit the bill would be Purpleheart, SG.86, Box SG.91, and Bubinga SG.88. There are numerous others, but these may be the easier to source, having made the goblets I would then treat them with at least 2 coats of Rustins Plastic Coating, it comes as a 2 part cold cure lacquer. See inset picture left, or click the link to our Finishing Materials page. If you use this method of finishing, it is completely waterproof, when properly applied and it does not matter what the SG rating of the timber is. This reply was compiled by Alec Mutch on behalf of A & R MUTCH (Woodcrafts). |
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Above, abstract carving in lime. By Stephen Hayward. |
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Above, some examples of Rams horn handles on our walking sticks, shanks are Chestnut, with collars of Buffalo horn and Purpleheart. By Ian Robertson. |
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(A) 37mm dia x 200mm high (B) 55mm dia x 285mm high. (C) 70mm dia x 215mmhigh. (D) 97mm dia x 185mm high. Click image for sundries page. |
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Question 4 From, Mr Mike Rowlands, Weston-Super-Mare, UK. Being new to Woodturning I am finding a problem with bowls splitting. It has happened to me on three occasions with Cherry, English Oak and Mahogany. All seem fine during the turning of the outside of the bowl but things seem to go wrong when I am finishing it off during the hand sanding stage. I have tried using power sanding, and using a bowl sander with pads but prefer sanding by hand as I seem to have more control. Am I sanding too much? or am I getting the wood too hot whilst doing it!. Most of these blanks were kiln dried, does that make a difference? Also does it matter the speed I have my lathe at, I usually have it at about 1000rpm?. Answer 4. Your problem with the bowls splitting, this could be attributed to several factors, not least of which could be the method and amount you appear to be adopting. Yes, you could be over sanding, and yes again, that you could be over heating the wood in the process. To hand sand successfully you need to keep the sanding medium constantly on the move, never dally in any one place for more than a second or two. Go down through your grades, and if it appears to be hot after any one grade, let it cool for a short while before you proceed to the next grade, also remember very slight pressure is preferred whilst sanding, a heavy hand will not produce good work. As for power sanding and its control, I have to say that this would be my preferred way, but it does need some practice to perfect. I use the Powerlock System, see inset picture left, or click the link to our Sanding Page. This is used with a power drill and both the drill and the work are running at the same time, but in opposite directions, that coupled with the lightest of pressure on the disc will produce an excellent finish, and again go through the grades, I only use 3 grades, 120, 180 and 240 grit, a final rub with 0000 grade steel wool and the jobs done, ready to seal and polish, for this I would use a Cellulose Sealer followed by Melamine Lacquer. You ask if kiln dried wood could be a factor, well in my experience I have never found it so, although I will say that I much prefer an air dried blank to a kiln dried one, I find all its working qualities are much better. As for the speed, that should be ok also. One cautionary word on the splitting, Oak is notorious for having short with the grain cracks, Cherry can also be prone to this too, Mahogany on the other hand is usually quite well behaved, so I do suspect its what you are doing that needs to be worked on. One last thing, I am assuming that a reasonable to good finish is being produced off the tool, (you failed to mention what that was, i.e. gouge or scraper), remember you will not sand a good finish into a piece of wood that has a poor finish to start with. This reply was compiled by Alec Mutch on behalf of A & R MUTCH (Woodcrafts). |
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Above, A Sycamore bowl. By Mike Rowlands. |
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Cellulose Sealer. Click the picture for Finishing Page. |
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Powerlock Sanding System. Click the picture for Sanding page. |
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Question 5. From Mr Mike Rowlands, Weston-Super-Mare, UK. A question for you Alec! Recently I was given some branches of Willow from a tree that was felled near my home. There are about 8-10 lovely straight pieces about 5thick and 10-12 long. There may be the possibility of some more in the future, in a variety of woods. I have put a good coating of melted Paraffin Wax on the ends of these. Now my question, firstly have I done the right thing waxing them? and secondly, do I store these in my fairly dry, dark garage? or is it best to dry them outdoors.? Since they arrived I have noticed that they are still producing new shoots, what if anything do I do about those? Answer 5. Yes you did the right thing waxing the ends. My only concern is that each piece is very short in the first place, 10-12 long will not give you a lot to work with after they are dry, you will have some end grain splitting, even although you have waxed the ends. As for the drying of these, what you are looking for is a place that gets no sun, kept dry and very draughty. A north facing wall would do just fine with some sort of cover above to keep off the rain, in addition the logs/branches should not be in contact with the ground, a pallet or something similar would do just fine. Lastly try to dry them standing on end, and if possible the right way up, i.e. as they were growing. They will take about 12 months for every inch of thickness to dry fully. Dont concern yourself too much about the new growth on your logs, they can never come to anything, they will eventually wither and die as the logs dry out, and indeed might be of marginal benefit, in drawing moisture out of the logs, so just ignore them. You mentioned that you may get some more in the future, let the person cutting the logs/branches know to leave them in as long a length as possible, provided you can still carry it, I like to cut all mine to around 6-8 feet long, this eliminates the majority of the splitting problems as I just remove about 4 inches from either end, taking all the splits away with that. You can use material a lot smaller than that you have taken, I use smaller branches, say 2-4 dia for making mushrooms, I also use bigger logs 6-10 dia for natural edged bowls, all are cut in long lengths and dried standing up, only cut into their useable lengths as and when required. The picture of the logs above, left, and in our Timber page, shows them ready to be turned, these are only cut to size after the drying process, not before. This reply was compiled by Alec Mutch on behalf of A & R MUTCH (Woodcrafts). |
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Some mushroom blanks, ready to be turned. |
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The finished mushrooms. |
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A natural edged bowl made from a whole Laburnum log approx 7 dia and cut at 9 long, |