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| MadNick:
Evening, Ive had a busy afternoon - after messing around with some designs for the past few weeks I finally made a start. The raw materials - The first step was to drill the mounting holes for the base of the cutter. Unusually my lathe does not have the usual T-Slot arrangement for the cross-slide. Instead I have this - I carefully double checked my measurements, set up the work in the vertical miller and got rolling. Now, im not going to blame the X scale on my DRO but the four holes I ended up drilling were out, way out. After checking over the X scale I realised it seemed to 'stall' halfway along - a quick adjustment and it was working correctly. Just to be sure I thought I would try some test cuts on a piece of scrap rather than using another decent piece of steel. I needed to be certain about the distance between centres on the cross-slide mounting holes. I measured up again, using the diameter of the head of the bolt this time rather than their diameter at the thread and got a slightly different set of numbers - I did a test cut - Offered up to the cross-slide this was a perfect fit so I setup mark 2 of the base and drilled using the measurements proven on the scrap - This was a perfect fit on the cross-slide and I was extremely pleased with my effort. Taking time to THINK, measure and check after the first ballsup had paid off. I need to rework my design as I hadnt factored the diameter of the bolt heads into the diameter for the turret. Ill either countersink these, cut the bolt head back a bit or a combination of both - this is when the T-Slot setup for a cross-slide really helps. Its easy to forget that 80% of this type of thing is measuring, considering and setting up - only 20% is spent actually doing anything. Nick |
| saw:
Good start, this will be an interesting project. :thumbup: |
| Rob.Wilson:
Looks like your off to a good start Nick :thumbup: Nothing better than a satisfying afternoon in the shop :dremel: Rob |
| Divided he ad:
Hi Nick :wave: I've lost count of the times I've miss-calculated things.... Often resulting in a re-design :borg: There are literally hundreds! :lol: I can tell you these tools are fun to use and make all sorts of interesting shapes possible. I use mine for a huge portion of my "styling" work. I quite simply, love the thing! Not having seen your design thread yet, I just thought I'd ask while I'm here. What cutting tip you're fitting? I only ask because I have details about double ended inserts that might fit your requirements? I would always go with a concave and convex cutting toolpost as it opens up the versatility of the tool. As said, not seen your design... I'll look after and you might have already answered that? Looking forward to seeing your progress :thumbup: Ralph. |
| MadNick:
Evening, Not much pysically produced today but my learning has improved tenfold. It was time to countersink the 4 bolt holes on the base. Realising that I didnt have a datum nor two square adjacent edges I was in trouble right from the start and just couldnt get the piece lined back the same position I had it yesterday - needless to say the countersink effort I made using a knackered 3/4" slot drill was unsuccessful and produced a far from concentric result. I tried to recover with a boring bar which worked but by the time the holes were concentric they were too big and looked stupid. I decided to get the hacksaw out, start again and not make the same mistakes. After hacksawing another approximate sized block of steel I clamped and faced one edge in the vertical mill parallel to a 'good' side. Realising that each of the 4 holes was going to need piloting, intermediate and then final drill, intermediate and then full countersink I made sure the piece was square to the milling head on the side I faced earlier and at 90 degrees on both X and Y to the head. Neither hell nor high water was going to make me remove the piece from the clamps until all drill/mill operations were complete. I did my stuff. It needs finishing and squaring off but I have produced exactly what I was after and worked to a level of accuracy I am happy with. The lessons learnt today? 1. Spend as much time as needed to setup the piece 2. Make a note of your datum, preferably a corner of the piece rather than the centre of a hole(!) 3. Work out what operations are needed and try to do them all while the piece is clamped in position 4. Make sure all your tools are in the same place - I used a knackered slot drill when I had a brand new, unused one in another cupboard I know this is probably 'old hat' to some of the pro's out there but i'm sure it will be of use to other beginners. Nick @Ralph, thanks for your comments. I bought a double-ended tip from the local toolshop for £1. It 'looks like' one for use with steel. Either way I intended to use a double ended one because then I can just spin the toolpost round to a cut concave radius and vice versa. |
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