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Beau Hannam Ukuleles
02-04-2015, 12:08 PM
Gluing up heel cap purflings- I like to do enough for 10 or so instruments.

I use 5 min epoxy (or West systems if im mixing up a batch anyway).

Using epoxy makes the sheets dry and stay flat.

If you try making a small batch with Titebond it will curl. Titebond is fine if your going to use it straight away.

Here im using 10 B/ 20 W/ 10B fiber (from RCtonewoods) to match my binding purfling (from stewmac)

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Beau Hannam Ukuleles
02-04-2015, 12:11 PM
glue it to the heel cap

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Moore Bettah Ukuleles
02-04-2015, 01:32 PM
......or you can just buy the sheets from Gurian. Any size and dimension you want.

Beau Hannam Ukuleles
02-04-2015, 04:52 PM
rctonewoods sell 36" x 5 or 6 " for $9 a sheet- pretty good price

Chris_H
02-04-2015, 07:15 PM
That amount of clamping pressure seems on the weak side. The spring clamps really do not do much, when spread out across that much area, especially with 5 minute epoxy, as it will start to gel pretty quickly. No that it probably matters much, though. 30 minute epoxy in a vacuum bag. Then there is minimal glue remaining.

Moore Bettah Ukuleles
02-04-2015, 08:25 PM
rctonewoods sell 36" x 5 or 6 " for $9 a sheet- pretty good price

I mean already laminated.

Beau Hannam Ukuleles
02-05-2015, 03:41 AM
That amount of clamping pressure seems on the weak side. The spring clamps really do not do much, when spread out across that much area, especially with 5 minute epoxy, as it will start to gel pretty quickly. No that it probably matters much, though. 30 minute epoxy in a vacuum bag. Then there is minimal glue remaining.

These are only 6" long x 1" wide- 2 clamps probably would have been fine- they came out super flat

I mean already laminated.

MMMmmm...pre laminated.... (in homer simpson voice)

chuck- do you buy big sheets of pre laminated stuff then cut it it purfling, heel caps etc?? how much is a sheet??

Timbuck
02-05-2015, 04:40 AM
I use thin acetone based adhesive on my BWBWB rosette laminations. :)..Works for me !

sequoia
02-05-2015, 09:10 AM
This is a great post because I did pretty much the same thing and got not so good results. I laminated with CA glue. It looked great until sand out when the lines got ragged and tiny sheets came off. I was very disappointed. I must have done something wrong, but the fiber stuff did not sand well for me at all. See below. Note ragged white line. (please ignore crappy healcap join to body. please)



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Beau Hannam Ukuleles
02-05-2015, 09:35 AM
Fiber is pretty hard stuff- especially when hit with ca glue- i usually chisel, file and sand the excess off

Kekani
02-05-2015, 12:49 PM
30 minute epoxy in a vacuum bag. Then there is minimal glue remaining.
I just sealed up my reservoir for my venturi vacuum yesterday. Making my bridge clamp now. This should be fun when I start doing preshaped braces, on a radius.

Yes, plan on doing some veneering as well. Got some carbon fiber sheets, maybe I'll see what kind of layups can be done.

Beau Hannam Ukuleles
02-05-2015, 02:33 PM
I just sealed up my reservoir for my venturi vacuum yesterday. Making my bridge clamp now. This should be fun when I start doing preshaped braces, on a radius.

Yes, plan on doing some veneering as well. Got some carbon fiber sheets, maybe I'll see what kind of layups can be done.

I was thinking of going to go the vacuum clamping method for bridges on ukes- let us know how it all goes!

Kekani
02-05-2015, 09:13 PM
I was thinking of going to go the vacuum clamping method for bridges on ukes- let us know how it all goes!
When I'm done, I'll call it out of the box. . .

Tested it, with a makeshift clamp - I need to install the fitting in the frame, and not the rubber (the hose is too heavy for that small an area). Clamped a bridge blank to my bandsaw table, holy crap! I was concerned about "atmospheric pressure" not being enough, but I get it now. Is it needed? Probably not. Is it cool? Definitely!

Beau Hannam Ukuleles
02-06-2015, 04:30 AM
How much do you think it would cost to get a cheap vacuum setup going???

Kekani
02-06-2015, 05:00 AM
If you have a good compressor, Joewoodworker.com has the plans. Veneer supplies has the parts (same guy). Less than $200 for the V2plus, unless you want to go with a pump, then less than $400. I should've bought the whole kit from them, instead of trying to piecemeal the fittings (was more $$$ in the end).

Beau Hannam Ukuleles
02-06-2015, 05:48 AM
Did you buy the vacuum bridge clamp from LMI or just make one??? --- https://www.lmii.com/products/tools-services/vacuum-tools/vacuum-bridge-clamp

Im a bit of a dumby when it comes to making jigs n things.

Kekani
02-06-2015, 05:57 AM
I'm making mine. I went with a venturi because I have a compressor, so I didn't need the pump. If I couldn't make the system, I probably wouldn't have bought it and just do without. But, this thing looks to be very cool.

Chris_H
02-06-2015, 06:38 AM
Here is mine. I made it. The hose goes to a nice vacuum unit made by vacupress. https://farm9.staticflickr.com/8492/8308892690_8bea3e3662_o.jpg (https://flic.kr/p/dEefjw)

Beau Hannam Ukuleles
02-06-2015, 07:16 AM
It seems SOOOOOOO much easier then clamping into small instruments- Tenors are just ok witht eh short stw mac clamps but concerts are frustrating.

Is it hard to make a bridge clamp like this ???????- What kind of material is needed on the face that touched the instrument?

Moore Bettah Ukuleles
02-06-2015, 07:41 AM
Seems like a lot of fuss and expense just to clamp a bridge. Then again, I am not a tool freak and I only glue 4 bridges a month. As far as clamping on smaller sized ukes I've made my own cam clamps. Easy peasy.

Kekani
02-06-2015, 08:02 AM
I use Baltic Birch ply for all my jigs. Weatherstripping touches the surface- I need thicker stripping.

It is a lot of fuss, and like I stated, if I had to buy it, I wouldn't.

This is fun for me, with a usable end. The kicker was when I saw my friend press braces on a radiused back. I asked him "30 minutes?" He said he can pull it out in 7. From what I've read on the all knowing internet, 15-20 seems about right. Not that I'm in a rush or anything.

I look at this as something I want to do because I can, not because I have to.

Beau Hannam Ukuleles
02-06-2015, 08:28 AM
yer- i read somewhere that glue sets quicker in a vacuum. Logic would seem to be the opposite, but i'm not very logical.

Chris_H
02-06-2015, 08:42 AM
Glue sets more slowly under vacuum.

Setting up vacuum only for clamping bridges might be a bit excessive. I use my vacuum setup for laminating, and it is an essential tool for me. Making that bridge jig took me a couple of hours of fun. On one of the websites that sells vacuum supplies, the vacuum gasket tape is available, that is the material that contacts the instrument top.

If I were building instruments as a career, I would probably set up with a vacuum clamp setup that holds the body for things like sanding the sides, that gizmo that LMI?? sells.

I still cannot quite wrap my head around clamping all of the bracing on a top in one press of a vacuum frame, but if that could be figured out, it might be a superior method, as the clamping pressure is so much more even than point contact clamping, and stronger too. There would be a learning curve, as with anything, but after that.... simples....

Pete Howlett
02-06-2015, 11:52 AM
One word - clean-up...

Chris_H
02-06-2015, 01:04 PM
Same as it ever was... pop the lid and scrape when the glue is green.

Chris_H
02-06-2015, 01:05 PM
Obviously some skill is required in knowing how much glue is too much.

Michael Smith
02-06-2015, 01:09 PM
I have found the deep throat clamps from Harbor Freight with a small block of wood taped on to clear the traverse brace work fine and only cost a couple of bucks. I have a couple of vacuum pumps but don't use them. I can't wrap my mind around not being able to clean glue up right away or unclamping a vacuum clamp, cleaning up then reclamping. I don't like the idea of that process.

BlackBearUkes
02-06-2015, 02:32 PM
If I had to use any kind of machine or electricity to clamp a bridge, I'd call it quits. To each his own.

Moore Bettah Ukuleles
02-06-2015, 03:38 PM
If I had to use any kind of machine or electricity to clamp a bridge, I'd call it quits. To each his own.

Yeah, it's really not that hard is it? And I've never had a bridge fail using the old tried and true method.

Beau Hannam Ukuleles
02-07-2015, 05:32 AM
Yeah, it's really not that hard is it? And I've never had a bridge fail using the old tried and true method.

No it isn't hard, and I too have never had a bridge fail from clamping with clamps. I always worry about the possibility of denting the top with clamps though (not that I ever have in 12 years of building). It is possible to over clamp though and get crimping on the bridge ends (this would be possible with a vacuum though i suppose).

Moore Bettah Ukuleles
02-07-2015, 05:47 AM
No it isn't hard, and I too have never had a bridge fail from clamping with clamps. I always worry about the possibility of denting the top with clamps though (not that I ever have in 12 years of building). It is possible to over clamp though and get crimping on the bridge ends (this would be possible with a vacuum though i suppose).

Then worry away! ;)

Beau Hannam Ukuleles
02-07-2015, 07:26 AM
HAHAHHA- I like to create a problem so i can buy another piece of kit to fix it :)