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TheHappyWombat
02-06-2018, 04:25 AM
Hi, i'm currently on my first ukulele build, i had jointed and joined the backplate and top plate together before doing thicknessing (they were about 3mm thick at the time) and was planning on thicknessing (using a hand plane) after they were joined. There were a few scratches and dings on the "show" side of the walnut back so i decided to do the thicknessing on that side of the back plate. It was when i was planing around the centre when my plane dug into the grain and ripped Out a few substantial chunks out of the centre of the board. I realised that the grain of the 2 halves of the plate were running in opposite directions, making it incredibly difficult for me to thickness with a hand plane. Or at least in the way i'm using it.

I'll be tossing the back and starting again but i would like to know of any way to avoid this problem. Do i thickness the plates before joining them? Or am i limited to sandpaper after joining? Or did i just screw up somehow since i can't seem to find anyone with the same problems as me on this or other forums and discussions.

Any and all input is greatly appreciated, thanks guys.

printer2
02-06-2018, 05:22 AM
You might try planing across the grain.

Sven
02-06-2018, 08:35 AM
The problem will increase if the runout is too great. Some runout can be handled by planing across but most important is an extremely sharp plane iron. Are you good with a scraper?

TheHappyWombat
02-06-2018, 03:26 PM
I do have a scraper but i'm having difficulty sharpening it to an acceptable degree, i usually just take out dust and the occasional shaving. Any tips for getting a good edge on a scraper? Thanks

resoman
02-06-2018, 03:59 PM
There are a bunch of sharpening videos on Youtube. I think Stewmac has one too.

DPO
02-06-2018, 04:02 PM
I do have a scraper but i'm having difficulty sharpening it to an acceptable degree, i usually just take out dust and the occasional shaving. Any tips for getting a good edge on a scraper? Thanks

I file the edge flat then burnish it with a tungsten burnisher ( a nail punch works just as well ) to turn the edge over forming a hook which does the cutting. Lots of vids on Utube. Once you get the hang of it it is a quick and simple process.

dofthesea
02-06-2018, 06:00 PM
Try planing on a 45 degree angle off the grin you will have much better luck. And start saving your quarters for a thickness sander you can get a small 10-20 for $300 used.

sequoia
02-06-2018, 07:48 PM
[QUOTE=TheHappyWombat;2039384 i can't seem to find anyone with the same problems as me on this or other forums and discussions.[/QUOTE]

What you are encountering is the perennial problem of thicknessing your timber. In my opinion, this is the most difficult part of the building process. Yes you can plane the plates and yes they are going to chip and tear out. My advice: get it reasonable close with a smoothing plane and take it down to final with a hand held orbital sander. Your aining for about 0.80 inch or so. Good luck

Wildestcat
02-06-2018, 09:31 PM
As mentioned by others above, many years ago my first guitars were made using the technique outlined in William Cumpianos book: Plane at 90 degrees and 45 degrees across the grain from both directions and follow up with planing with the grain runout in opposite directions for the two halves of the board, taking great care near the centre line not to run over it. Repeat the sequence as required. As you approach final thickness a sharp, well adjusted plane is ever more essential and I always skewed the cut (angle the plane across the direction of travel). Even then chipout was an ever present issue and I eventually bought a No.112 scraper plane for finishing rosewood.

Thankfully an investment in a thickness sander means all this is now history! :)

Just remembered the other Cumpiano tip - use a toothed blade for the cross grain cuts in particular. Then take off the ridges with the standard blade. This also helps maintain an even thickness. I had an old Stanley No 4 that was pretty useless in the conventional sense, so I ground teeth into the blade and kept it for that purpose. If you only have one plane it might be a tad wearying changing out the blade though! I never had to try hand thicknessing a ukulele top/back/sides set and since there will hardly be any room for clamping down, it doesn't sound like much fun! I suppose a vacuum clamping system is the answer?

Jardin
02-07-2018, 04:30 AM
First off make sure you have plane that is true, sharp & well tuned...I cannot stress how important this is!
There are lots of youtube videos to help you do this. If you are just picking up a plane that you bought at a garage sale or even some of the cheaper brand new handplanes out there, they may not be flat enough. So if you have not seen to all that start there. You want it to be really sharp, the blade to be making a very light cut and even from side to side. Take the time and set it up right after each sharpening.

I made a simple bench hook with a 1.8mm strip to hold my plate in place while thicknessing. I would then thickness each half in rotation until I was getting close to my target. Then I joined and finished with a scraper (or orbital sander if you cannot get a proper burr). Of course you have to be more precise with your join so as to make certain there is not a whole lot to take off. In other words make sure your join is flat and that there is enough meat to clean everything up.

I did just fine thicknessing across the grain exclusively but I also am careful about not dipping towards the end and being very methodically even about everything. Take your passes with the plane at a slight angle across the grain, rotate, take your passes again and then do the same to the other half. Even strokes, take your time, check thickness often. I also found that I had better results by planing some off the other side as well as it help with the wood drying at an even rate and therefore not cup (but I live in the desert and things react quickly here). After you get it all done keep weight evenly across it to allow it to dry straight.....This is especially important if you have humidity swings. I sticker all my wood and place weights on them just to be sure.

It is hard to describe all this in words but it is very doable and even enjoyable if you like this sort of thing. I just love the curls of wood coming off. It is so satisfying. Hardwoods are actually pretty easy.

I sure hope this helps....Don't give up!

sequoia
02-07-2018, 04:57 PM
I made a simple bench hook with a 1.8mm strip to hold my plate in place while thicknessing.

A lot of times in woodworking, just holding the wood in place can be half the challenge. I would be interested in pictures and/or descriptions of your simple bench hook. Thanks.

Jardin
02-08-2018, 08:46 AM
106544
106545

Here you go Sequoia.....Pretty simple but very effective....

A whole lot faster and easier than clamping....Unless you have vacuum clamping capabilities.....but that is above my paygrade.
I have never had a problem with it and all I have to do is pick it up and rotate or flip depending on what my next move is. Notice that this only fits an oversized board of half a top or back, yet long enough to do sides as well. Nothing like simple & cheap.

Friesen5
02-08-2018, 12:14 PM
I posted this on another thread. This is a cheap way that I used to make an effective vacuum clamp.

http://forum.ukuleleunderground.com/showthread.php?130880-No-Drum-Sander-Use-this&p=2031906#post2031906

Mervin Friesen

sequoia
02-08-2018, 05:58 PM
106544
106545

Here you go Sequoia.....Pretty simple but very effective....

A whole lot faster and easier than clamping....Unless you have vacuum clamping capabilities.....but that is above my paygrade.
I have never had a problem with it and all I have to do is pick it up and rotate or flip depending on what my next move is. Notice that this only fits an oversized board of half a top or back, yet long enough to do sides as well. Nothing like simple & cheap.

Thanks for the pic. Yes, that is the way to go. Maybe the only way to go... Here we just call them cleats. Also a little piece of double sided sticky tape under the plates helps hold everything in place. Holding things in place with your hand as you try to thickness with a plane just doesn't cut it. (Ha!)

Michael N.
02-08-2018, 09:14 PM
I don't think it's been mentioned yet but learn to fit and set the blades cap iron very close to the edge of the blade. That really does help in reducing tearout - along with all the other advice, like SHARP!!! You may have to do some work on your cap iron dependent on what plane you have. There's probably some u-tube video that addresses the cap iron, it's fit and the use of it.
As for that thicknessing back/side holder. You don't necessarily need to tape the sides or back down providing you plane across the grain - which you have to otherwise you are in danger of them bucking and cracking. Using a long plane helps because it's the front part of the plane that becomes the clamp.

printer2
02-09-2018, 02:49 AM
Just as an alternative, I bet a vacuum cleaner could give enough negative to hold a plate.