|
|
mikes-models.com |
mikes-models.com |
hints and tips page |
Hints and tips. 1 How to get away with machining errors and so called scrap! 2 Screw cutting.....and setting the top slide angle 3 Reading the signs of the grades of aluminium 4. Turning to the correct size on a lathe. 1. production of scrap! If you are a relative beginner as I am, then the production of 'scrap' or perhaps mistakes should not be called scrap! Rather they should be called 'items that have been resized' and ready for future use at somewhat of a smaller project. It works for me and I am an expert in such 'resizing'! ---------------------------------------------------------------------------------- 2. Screw cutting and the setting over of the top slide. I have to reinforce the fact that I am a novice and this 'hint' is not for the experienced! I have today tried internal screw cutting (see the Mills 1.3cc crankcase diary entry for 19/02/08). Now reading the books you have to set the top slide over to 29.5 °. So looking at my top slide there the manufacturer has very kindly engraved the degree marks. I set it over to 29.5° and proceeded to cut the threads. I wasn't very impressed with my results really so went back to the books. Re reading them its the angle of 29.5° against the cross slide! A completely different setting! Double Doh!!!! So my hint is not to anticipate that because the nice men engrave degree'son your topslide, that thats what you need. Read and re read is the answer. ---------------------------------------------------------------------------------- 3 Reading the signs of the grades of aluminium The identifiication of the grade of those blocks of aluminium gathered from your local scrap yard would be useful. Ron Chernich very kindly assisted me with an answer published in full on the correspondance page. However, Ron uses mill marks and surface oxidation to help. The photo to the right shows some oxidation which is a good sign! click |
4 Turning down to the correct size on a lathe |
This isn't one for the 'old sweats' more for the like of me 'novices'. Its not even mine but it does work and its so simple! Well it nearly always works and is 200% better than I have achieved before. Get on with it man I here you say....OK, how do you turn down to size every (nearly) time? You take the cuts you would normally make until you get near to size. Then measure the work piece and halve the amount to take off. You keep doing this until you are a thou away when you can either take a light cut or polish off as it were. It seems simple but it does really work! I read it in a recent UK model engineering magazine (don't ask me which, I can't find it !). Anyway, try it and you will be surprised. I was. |