Murphy's Law

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Hippety Hop
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Murphy's Law

Post by Hippety Hop » Fri Mar 20, 2009 11:21 am

Things that go wrong.

Image

Clamped it up like this last night with no glue just to try it out. I was getting a bit tired, so I went to bed and left it. Un-clamped it this morning, then glued and clamped it up exactly the same way, and after a good inspection, left it. A couple of minutes later I looked and it was sagging down toward the bench. I reached out and grabbed it just as it dropped into my hand.

Image

The cork pad on the cam clamp had slipped. That's one of the cam clamps from Timbecon. Should have known. A couple of them cork pads have slipped before, and I've stuck them back with titebond. I'd better do them all. Luckily I didn't do any damage. It most certainly would have bounced off the edge of the bench, and crashed to the floor.

Hip.
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Post by kiwigeo » Fri Mar 20, 2009 11:26 am

Hey Hip those cam clamps from Timbecon are a pain. Every clamp Ive got from them has had the cork poorly secured. The cork is also paper thin. Ive gone through and reglued thicker pieces of cork on my clamps. I get cheap cork sanding blocks from Mitre 10 and slice them up on the bandsaw.

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Post by Rick Turner » Fri Mar 20, 2009 12:07 pm

I would highly recommend gluing up on a workboard at least; easier yet is to put the body in a mold and glue up the top and then the back in a go-bar deck. Asking a clamp to do double duty...suspend the instrument AND be part of the top to sides glue up is sending out a big invite to our pal Murphy. That's a lot of weight to be hanging off of a cam clamp. If I were the cork, I'd have slipped too.
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Post by Kim » Fri Mar 20, 2009 1:11 pm

I am with Rick, use a work board.

The affect of all that weight focused at just one point during glue up is just asking for trouble. It is not just the fact that the cork could slip as it did or that clamp held in the vice could otherwise fail leading to the whole lot falling to the ground, but my concern is that all that weight hanging from one point creates a cantilever affect loading tension into the sides that will eventually transfer into the back or top once the glue dries.

This may not seem too much of an issue upon first thoughts, but why invite anything into the process that has the potential to lead to problems down the track.

Cheers

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Post by DarwinStrings » Fri Mar 20, 2009 6:18 pm

Nice catch Hip

Jim

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Kim
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Post by Kim » Fri Mar 20, 2009 6:45 pm

Yes indeed, nice catch Hip :wink: Sorry if I came across a bit blunt in my earlier reply, I was in a hurry tis all.

Anyhow here's safe-T-tip No73 from Kim's school of sharp things and beer. Always try to maintain the saw dust and shavings at least ankle deep on the shop floor while you work. Doing so is not only very comfortable under your bare feet, it will ensure a soft landing for both you and your work piece every time you fall over.

As an added bonus, the shavings also double as a comfy mattress when ever the missus won't let you back in the house for being an idiot :D

Cheers

Kim

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Post by Hesh1956 » Fri Mar 20, 2009 9:18 pm

Kim wrote:Yes indeed, nice catch Hip :wink: Sorry if I came across a bit blunt in my earlier reply, I was in a hurry tis all.

Anyhow here's safe-T-tip No73 from Kim's school of sharp things and beer. Always try to maintain the saw dust and shavings at least ankle deep on the shop floor while you work. Doing so is not only very comfortable under your bare feet, it will ensure a soft landing for both you and your work piece every time you fall over.

As an added bonus, the shavings also double as a comfy mattress when ever the missus won't let you back in the house for being an idiot :D

Cheers

Kim
Kim my friend if I had that much dirt in my shop I would stroke out..... :D

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Post by Rick Turner » Sat Mar 21, 2009 2:08 am

I've seen shops where the chips and sawdust were literally above ankle deep...one was a tiny subcontracting shop about 30 miles outside of Pusan, Korea in which there was a large pin router, a dangling 60 Watt light bulb, and a guy cranking out bodies for electric guitars that would eventually have little loudspeakers and amplifiers built in. The other shop was a hole in the wall...almost literally, in Santo Domingo, Dominican Republic. It was in the lumber yard district, and there was one guy and a lathe, and he was knee deep in shavings. He was making turned spindles...balusters...for railings, and he was duplicating a pattern by eye and doing pretty amazing work. I got the impression that he wouldn't bother sweeping the shavings out until they got up to the level of his lathe tool rest!
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Post by kiwigeo » Sat Mar 21, 2009 10:32 am

Amazing stuff Rick.....what a contrast to Hesh's workshop. Word is when the local hospital had an outbreak of golden staph and were forced to use Hesh's workshop as a temporary operating theatre. :shock:

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Post by sebastiaan56 » Sat Mar 21, 2009 5:05 pm

Yeh, Ive been in food factories like that Rick,
make mine fifths........

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Post by Hippety Hop » Mon Apr 13, 2009 11:51 am

I'll be buggered...

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Just spent at least an hour sweating outside in the sun with the mask and apron on, and then just on the last little bit and the glue gave way.
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Post by DarwinStrings » Mon Apr 13, 2009 11:32 pm

What happened Hip. I'm not sure what you've done? Nice looking bit of wood and binding work though.

Jim

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Post by Hippety Hop » Tue Apr 14, 2009 12:04 am

Jim, the plastic binding strip virtually fell off. The end bit flipped up as I was sanding it, so then I hooked my finger under it and it peeled off far too easy for my liking.

I got another strip and scratched one side of it with a saw blade. Should grip better this time.

Hip.
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Post by Allen » Tue Apr 14, 2009 6:00 am

Has the binding let go?

Oops, you were posting as I was.
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Post by DarwinStrings » Tue Apr 14, 2009 9:37 am

Ok I can see the binding in the pic now and didn't notice it before. I am curious about which glue you used.

When I said nice binding work I meant that rosette and the inlay around the rim.

Jim

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Post by Nick » Tue Apr 14, 2009 11:19 am

I'm with Jim, what sort of glue you using there Hip? doesn't appear to have keyed to anything, the wood or the plastic!
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Post by Hippety Hop » Tue Apr 14, 2009 4:56 pm

Titebond alright? I hope so - I've used it again...

Image
Image

Looks exactly the same as before. I think the plastic was just too smooth so the glue couldn't grip.

Just bought this thing to help clean it up. It should arrive just after the binding on the back is dry.

Oh yeah, the top is Tim's streaky myrtle, and the rope purfling is Tim's as well. The back and sides are zebra wood from RC. Both the rope and the zebra are mongrels to bend.

Cheers Hip.
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Post by Allen » Tue Apr 14, 2009 5:15 pm

What the heck are you going to do with that belt sander Hip? Looks OH SO DANGEROUS to me for any sanding on a uke.

Plastic linings aren't going to like the heat that is generated from a high speed sanding belt, so if you're determined to give it a go, just be careful.
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Post by kiwigeo » Tue Apr 14, 2009 5:33 pm

Hey Hip dont let that belt sander anywhere near that uke. Cabinet scrapers and/or sandpaper on a block are the go.

Titebond is for wood....its not going to work to well with plastic. I think a solvent based glue is the go....dont know what other people use as I dont let any plastic bindings near my babies.

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Post by Hippety Hop » Tue Apr 14, 2009 7:11 pm

I'll be gentle.

Perhaps I was a bit hasty. Oh well - just another cheap power tool to throw on the pile.

Suppose I can use it on my eczema. Image
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Post by DarwinStrings » Tue Apr 14, 2009 7:11 pm

I'm with Martin Hip check this thread out it has some suggestions http://www.mcguitars.com.au/forum/viewtopic.php?t=1286

Jim

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Post by Hippety Hop » Tue Apr 14, 2009 10:33 pm

I was tempted to try the "Great Planes" 6 minute epoxy on the back, but I had a good pick at the ends of the top binding with my pocket knife and it seems firm enough now, so I glued the back binding on the same way.

Now my rhubarb & apple crumble smells like it's ready.

Image

Cheers Hip.
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Post by Nick » Wed Apr 15, 2009 5:58 am

Glad the Titebond seems to have worked. I usually get acrylic glue from a plastics supplier, it works by melting the surface layer of the plastic and soaks into the wood thereby keying the two together. I'm with Martin, level using only scrapers, anything else generates too much heat and I think you'll find the binding pops off again.
Nice crumble by the way 8)
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Post by kiwigeo » Wed Apr 15, 2009 7:01 am

Hippety Hop wrote:I'll be gentle.

Perhaps I was a bit hasty. Oh well - just another cheap power tool to throw on the pile.

Suppose I can use it on my eczema. Image
Hey Hip......that belt sanders a GMC? I doubt youd get the skin off a milk custard with that piece of rubbish. Flog it and use the money to buy yourself a set of decent cabinet scrapers and some garnet paper.

*****ng nice looking pie

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