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Who here is utilizing a vacuum for sides? I need to develop a vacuum system after breaking a few maple super curly sides for Ukulele.I have a Please share your system. I'm wondering if it's just because of the severe runout in the maple.

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I started playing with vacuum bagging sides about 18 months ago. All of the tools and supplies were sourced from Veneersupplies.com . I uses the 4x4’ 30mil bag.

I like the Unibond-one for the lamination glue - long open time and it dries hard.

M

I’m using the Veneer Supplies setup for the bag and pump. It’s a great system and the pump only cycles once every few hours.

https://www.veneersupplies.com/products ... s-Kit.html

For glue I’m using the Unibond 800 with a bunch of coaching from James Orr over the years. It goes on quickly with a foam brush and has plenty of open time using the slow set mixture of hardener to resin. Someone shared here a while back this link which is the only place I’ve found it in quarts. Much easier to use before it goes bad.

https://nelsonpaint.com/unibond-800-ure ... ive-quart/

I have used this setup for solid lining for years and it works great and just did my first set of double sides using dyed black veneer from Dyed Veneer. Don Parker recommended them and they are great.

https://www.dyed-veneer.com/Dyed-Wood-Veneer-s/139.htm






Brad


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Awesome tip on the quart-sized resin!

Another vote for bags (“build-a-bag” - I like the polyurethane material) and pump tech from Veneer Supplies. I’ve been using gorilla poly glue for laminating and once I got a proper handle on the amount of glue to use it’s been great but I think I’d like to try the Unibond. Be sure to buy the breather mesh.

I recently started vacuum bagging ukulele sides after years of laminating them with clamps and cauls. With either method, the sides have to be pre-bent in the usual way on an iron or bending machine, although less precision in the bending is required. My laminations are two pieces of material at .040" to .050".

I tried UniBond 800 after long using red Titebond and quickly went back to Titebond. I found that the UniBond was nasty stuff, expensive, and didn't do the job any better than Titebond. Having done dozens of instruments that way, I decided to stick with Titebond. I roll it on the parts very thinly with 3 inch wide paint rollers cut from the standard 9" lengths. I use rollers that have plastic tubes covered with foam that is about 1/8 inch thick. These are easily washed in water and can be reused many times before they give out.

I built a vacuum pump 9 or 10 years ago from the plans and parts from Veneer Supplies. I've used this set-up quite a bit for not only bagging sides, but also for doing top and back laminations in radius disks and clamping assembled bodies so they can be worked on easily. I've lately been using a vacuum clamp to glue bridges and I can't figure out why I didn't start doing it years ago.

The pump system has worked flawlessly except for the failure of one small control part. Joe at Veneer Supplies quickly diagnosed the problem by email and sent me a new part. Just about every element in the system came from Veneer Supplies, and I can't speak too highly of the quality and service.

For photographs, check the blog section of my website at onoukes.com

I’ve been doing double sides with Unibond 800 and cauls for years. You guys have thinking about vacuum again. Any pitfalls?

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The only issue I’ve had, if you want to call it that, is that I needed to make a shim for my bending form to take up the extra .020” thickness of the bending slat. It was either that, or make yet another form that was exactly offset to .100” which is the thickness of my sides (.06 outer, .04 inner).

What I did was take a sheet of fiber that was .010” and layered packing tape to get to .020”. This made it the right thickness but also protected it from the glue.



Hope that is clear, let me know if not. It’s a great setup with predictable results.

Brad


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David,

Per our conversation last night - here are the links to the bag, fitting and breather mesh:

Bag - https://www.veneersupplies.com/products ... 2-x-4.html
Fitting - https://www.veneersupplies.com/products ... ector.html
Breather mesh - https://www.veneersupplies.com/products ... shNet.html

Brad

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I use bags from Amazon used for storing blankets. Less than $2.50 per bag. I use it for laminating both sides, then throw it away. I also got the vacuum connector from Amazon. I put a little poly fill (like the use in cheap pillows) between the connector and the mold so all of the air gets sucked out.

For the sides, I use either EIR or mahogany on the inner layer, depending on the guitar I'm making. I've been using LMI practice sides for the EIR, but I need to find a new source for that now. For the mahogany, I bought a bunch of 'B' grade sides that work well.

I'm using System Three T-88 epoxy, because it has a 45 minute working time.

I thicken the epoxy with silica so it doesn't squeeze through the wood as much.

Cleanup is a pain. I use the Stewmac ultimate scraper and sharpen it about 10 times through the process. The mini grinder they sell sharpens it in about 10 seconds, though.

I use spanish cedar bent to the shape of the guitar instead of standard kerfing to give me the last little bit needed to support the binding cuts. It's a lot thinner than kerfing because of the extra side thickness. Also, I'm not using side braces now, because I have laminated sides.

https://www.amazon.com/Vacuum-Bagging-Connector-Carbon-Fiber/dp/B07H8PNHRC/ref=asc_df_B07H8PNHRC?tag=bingshoppinga-20&linkCode=df0&hvadid=80264400674211&hvnetw=o&hvqmt=e&hvbmt=be&hvdev=c&hvlocint=&hvlocphy=&hvtargid=pla-4583863979582247&psc=1

https://www.amazon.com/gp/product/B07MKQY3FS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B005H1PLOM/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B002K9R51Q/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

https://www.stewmac.com/luthier-tools-and-supplies/types-of-tools/scrapers/stewmac-ultimate-scraper/?queryid=b9fc0b21c51e6b140d3a8ecbe6da0628

https://www.stewmac.com/luthier-tools-and-supplies/types-of-tools/scrapers/mini-grinder-for-ultimate-scrapers/?queryid=32872ee552c648f2283395fcca33ec9e

I’ve made 5 instruments with lam sides and backs but I use the reverse mold. In other words the veneer that shows is against the mold. Yes on the breather mesh . I’ve used the titebond extend for the backs and unibond for sides,
I buy off the shelf veneers from certainly wood


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Mike McNerney

Interesting! I have put the sides in the bag first and then pressed the whole thing onto a mold. I didn’t think the bag (I have exactly the same setup from Veneer Supplies) would stretch and conform if I put the whole shebang with the mold into the bag. Wish I’d had the cojones to try.

Also, has anyone tried foam or Nomex cores to thicken the sides to 1/4”? I always wanted to try for supper ridged sides (and possibly no need for linings).

In a related note, is there anywhere to source 1/16” or 1/20” curly maple veneers? 1/42” is just too thin, and putting two consecutive sheets together can sometimes leave sand though witness lines.


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Per Mike McNerney's post just above yours try Certainly Wood. That's where I purchased 1/16" curly maple veneer for my vacuum molded ES-335 style top and back plates.

I don’t doubt you, but I guess I just need to get better at searching because all I found was plain maple at Certainly in that thickness.


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at the moment they only have 4 to 6 wide curly maple. Sign up for their newsletter. they get stuff regularly. They have some great monkeypod and some new kind of qtrd ebony right now.
you might have to build up 3 layers to get the finished thickness you want

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Mike McNerney