Welded frame and Oak bowl

Over the weekend the frame for the teardrop was welded up, big thanks to Dave for teaching / showing me how to weld this and to Matt for putting up with us welding up the frame when we should have been working on fixing his car…

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The frame had to be rotated around a few times to get all the welds complete, initially it was tacked upside down after which all accessible welds were complete.

After that it was flipped and the top was welded (note these welds will need to be ground flush for the wooden floor to sit flat)

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When complete this was loaded back onto the trailer (pretty good two man lift) and transported home where the welds were ground flush with an angle grinder and flappy sanding disc.

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Weld pre grinding

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and then post grinding

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The other project for the weekend was the turning of an Oak bowl. A number of months ago a large tree was removed at my parents place, I managed to save a few sections for turning and also cut one of the larger sections into slabs (still to see how this weathers).

The sections destined for turning had their ends coated with wax to help prevent them from splitting from drying out too quickly. Walking past one of them over the weekend I noticed that some of the wax had started to crack and not wanting the wood to start splitting I decided that it needed to be turned.

I still don’t have the ideal setup for turning bowls, OK for spindle work but the swing over the bed is less than ideal and moving parts from the outside end of the tailstock to the inside is a bit of a pain.

Rough turning was completed on the outside at a fairly low-speed, this is where having the three-phase motor really comes in handy.

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At this point the bowl as just screwed really well onto a faceplate.

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After the outer shape was complete an attachment point for the chuck was cut into the bottom before the blank was shifted to the inboard side for hollowing out.

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Some sanding is still required and I’d like to make the walls a little bit thinner if possible but once again the current lathe setup isn’t conducive to turning bowls, there is only a limited amount of room on the far side of the lathe before hitting the wall which makes it hard to get a bowl gouge in.

Given this was the first turning completed in a while all the chisels were in a bit of a state and so required touching up. Previously I had the Teknatool Nova jig mounted on the bench grinder but to be honest found it less than ideal.

According to the instruction manual for 8 inch grinders you are supposed to mount the jig on a raised block. The issue then was that the jigs slide didn’t fit under the grinding wheel and so there was only a limited range that the slide could move in and out. Another minor annoyance was the method of locking off the slide, basically a small rod inserted through another shorter threaded rod with two small rubber caps (designed to but not really) stopping the rod from sliding out of the threaded piece (picture below missing the rubber caps).

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In practice I found that the rubber caps would fall off and then the smaller rod would constantly slide out of the bottom part when tightening and then roll around the floor. I also found that once you had used the grinder for a while a deposit of ground material would build up on the slide which would then drastically increase the friction between the slide and clamp when moving it in and out.

I also found had a few issues with the top part of the jig. The cast section never seemed to slide that well on the stamped / folded plate (tried oil, grease, silicon spray, graphite powder), also it was slightly annoying to have to disassemble the top section to swap between sharpening with the cast section and sharpening with the guide arm.

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My version didn’t have the black thumbscrews but rather a threaded rod with a 90 degree bend on one end and then on the other a wing nut. Also the angle indicator pieces further down were always a bit of a pain to fit back in. The red folded piece was about 5mm narrower than the silver piece and so had to be pulled out whilst you tried to fit it, all in all a bit too fiddly considering how often it needed to come on and off.

All these things made me look around at other options and in doing so came across the Woodcut Tru-Grind system, very similar to the Teknatool but with a few differences.

  1. Slide does not need to be mounted on a block for 8 inch grinders.
  2. Slide system seems to lock off better (lever at the side as opposed to clamp on top.
  3. Guide arm part has notches which positively locate it at 10 odd fixed angles.
  4. Has two cups allowing you to locate the support arm at two different locations on the arm.

This was fitted to the grinder last night and is looking promising so far, the geometry of the system seems to fit the 8 inch grinder better making it easier to get the correct angle when grinding.

I haven’t sworn off the Teknatool jig yet but for the moment will use the Woodcut one and see how it performs for a bit.

Both of these jigs have one minor issue however and it’s definitely scraping the bottom of the barrel but it would be nice if the markings on the slides were engraved or stamped as the printed labels options that both systems use don’t last long at all.

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