Jump to content
Maestronet Forums

Sanding block ( c bout and corners )


Arsalan
 Share

Recommended Posts

Hello everyone 

In the past there has been a few useful sanding block specially used for c bout and corners , I have attached a pic from one of them ( David sora use ;) ) ... it’s more than three months I keep looking for them but can’t find them ... I would rather buy them, as it’s very time consuming to make them and still won’t be as accurate as CNC ... 

I appreciate if someone can tell me where I can get them from ... 

thank 01382962-C08B-4486-B13C-5FEBCEF44BD1.thumb.png.4f153d998000eeeaf1fee4b6398c4c63.pngyou 

Link to comment
Share on other sites

Well, CNC accuracy is way, way, way beyond what you need for this, and making such doohickeys yourself provides a good opportunity to improve tool skills.

At the risk of outing myself as a total neanderthal, I do most of whatever sanding I need to do to an outline with sandpaper wrapped around chisel handles of appropriate diameter...

Link to comment
Share on other sites

5 hours ago, Arsalan said:

Hello everyone 

In the past there has been a few useful sanding block specially used for c bout and corners , I have attached a pic from one of them ( David sora use ;) ) ... it’s more than three months I keep looking for them but can’t find them ... I would rather buy them, as it’s very time consuming to make them and still won’t be as accurate as CNC ... 

I appreciate if someone can tell me where I can get them from ... 

thank you 

I don't think you will ever find them for sale, probably no one would buy them because they are too easy to make.;)

You can use the flat one to make curved ones, in the same way as you do for violin edges, eliminating the annoying problem to keep the squareness with a file used freehand.

Shapes don't need to be exactly the same as mine, as long as they fit your C's, keeping in mind that sandblock curves must be a bit tighter than C's to work.

But if you are so lazy to design them, this is the shape of mine:

1148105392_Attrezzobordicurvomisure.JPG.024158736c73e163da929371a788dc82.JPG1320678939_Attrezziperbordi2.thumb.JPG.d7109a40e18a53327a1bf17819caea0f.JPG1990682946_Attrezziperbordi1.thumb.JPG.02dc8459535e9a0d02bc1225b6a5d940.JPG156150714_Attrezziperbordi3.thumb.JPG.f7eaca48e19ebde30cc276f331235994.JPG800943235_Attrezziperbordi4.thumb.JPG.250f8fb3208927037209c72ec6faa2a5.JPG

Link to comment
Share on other sites

11 minutes ago, MikeC said:

Davide what is the sanding material that you attach to the block and where can I get some?  

They must have asked me a million times, so I kept the answer ready to copy and paste:)

Here it is:

Sandplates

The coarser (the black ones) I use are old Sandvik Sandplate (Swedish), but the production was interrupted many years ago (I bought a small supply then)

The finer ones (the silver ones you show in the photo) are NT Dressers that can be found on the market in small adhesive sheets :

https://www.cremonatools.com/nt-dresser-ps-11p-fine-0-2x54x80mm.html

 

The same company (NT Dresser) also produces coarse-grain ones as spare parts for their line of tools, they also produce simple flat sheets but they are not easy to find, the more available spare parts have bent edges and screw holes and need some adjustments to make them work  :

https://www.amazon.com/NT-Dresser-Sander-replaceable-M-20GP/dp/B0034YQWT2

A recent alternative is this "sharkskin" from StewMac, I've never tried it but seems promising, a little coarse perhaps :

https://www.stewmac.com/Luthier_Tools/Tools_by_Job/Tools_for_Sanding/StewMac_Sharkskin_Abrasive.html

I remember that there were some discussions on the forum on this subject, but I do not recall when.

To adapt them to the curved tools it is necessary to pre-bend them as much as possible with the help of a steel rod (I use the scrapers burnisher) carefully without causing angled folds, then I glue them with cyanoacrylate keeping them clamped for a long time with strong and tight adhesive tape, otherwise with the spring effect of steel it is difficult to keep them glued.


PS You can also find some useful information on this topic on Maestronet forum : https://maestronet.com/forum/index.php?/topic/339885-sandvik-sandplate-substitute/

Link to comment
Share on other sites

Before anyone asks, I also copy and paste the instructions for gluing the sanding sheets to the blocks. I have kept these too to save time to answer endless requests...:lol:

How to glue sandplates sheets to sanding blocks

Regarding the way to glue the abrasive sheets, the double-sided tape does not have the sufficient strength to hold the spring effect they will have on the curved blocks, and even for the flat ones it is preferable not to use it because it will not last long (the sheets last practically forever). I use CA (cyanoacrylate) glue which works great and reapplies easily in case some parts lift-off, which can happen especially at the ends. To glue them on flat blocks there are no problems, but for curved ones, things are a bit more tricky. It would be better to try to give a pre-bending being careful not to cause creases, to reduce at least a little the spring effect, by sliding them on a steel rod (I use the burnisher for scrapers). It will not be possible to give it the shape you want, but at least a slight curvature of the ends will help to obtain a snug fit and prevent them from lifting. I start by gluing one end and when it is dry I apply several dots of glue along the entire length, then I carefully make adhere the sheet till the opposite end, where I apply the glue evenly for at least 1 cm to reinforce this critical point. At the same time, I overlap a few turns of very strong tape (duct tape) pulling it in the same direction in which the strip was adhered, tightening it well to maintain the pressure, because although the CA glue should be almost instantaneous, due to the spring effect it is actually necessary to keep the clamping for at least a couple of hours to make sure it holds. Another trick to keep the ends glued is to insert one of them in a cut made in the block (see attached photos) and plan to glue the other end in a not too curved area in order to reduce the spring effect which could cause it to lift. You will need to do some dry tests to make sure the alignment is good and avoid sticking them crooked. Keeping the block resting on flat glass to do this helps. Sounds complicated? In reality it is not, you will just have to do a few tests, and if it does not work well on the first try you can always unglue the sheet and start over, not a big deal. To cut them will depend on the thickness of the sheets, I use simple scissors for the thinner ones and tinsmith scissors (see attached photo) for the thicker ones. As a finish touch when you have them glued, you will have to make a light pass on the grinding wheel to clean the edges of the sheet, so that they remain raised by a few tenths of a millimeter from the flat glass surface on which you will have to slide the blocks during working, removing any irregularities caused by the cutting with the scissors that will tend to slightly bend the edge.

Link to comment
Share on other sites

16 hours ago, Davide Sora said:

I don't think you will ever find them for sale, probably no one would buy them because they are too easy to make.;)

You can use the flat one to make curved ones, in the same way as you do for violin edges, eliminating the annoying problem to keep the squareness with a file used freehand.

Shapes don't need to be exactly the same as mine, as long as they fit your C's, keeping in mind that sandblock curves must be a bit tighter than C's to work.

But if you are so lazy to design them, this is the shape of mine:

1148105392_Attrezzobordicurvomisure.JPG.024158736c73e163da929371a788dc82.JPG1320678939_Attrezziperbordi2.thumb.JPG.d7109a40e18a53327a1bf17819caea0f.JPG1990682946_Attrezziperbordi1.thumb.JPG.02dc8459535e9a0d02bc1225b6a5d940.JPG156150714_Attrezziperbordi3.thumb.JPG.f7eaca48e19ebde30cc276f331235994.JPG800943235_Attrezziperbordi4.thumb.JPG.250f8fb3208927037209c72ec6faa2a5.JPG

Thank you very much David ... 

I don’t know if you read my massage 

but your hand works and arts , was what made me starting making a violin ... I made the first one ( spent maybe 700 to 1000 hours on it or maybe more 

but it sounds good ... I watched most of your videos and like them ... 

my first violin is here ... 

BEF96F9B-CCEA-4211-BB30-E584483E196B.jpeg

B7AF55DE-143B-4F6B-9CF6-85ABD7B475CF.jpeg

D9920FED-A47B-4A4E-9E53-F8719F6F5299.jpeg

Link to comment
Share on other sites

1 hour ago, Arsalan said:

Thank you very much David ... 

I don’t know if you read my massage 

but your hand works and arts , was what made me starting making a violin ... I made the first one ( spent maybe 700 to 1000 hours on it or maybe more 

but it sounds good ... I watched most of your videos and like them ... 

my first violin is here ...

Thanks to you for your patience in watching my videos, I realize it takes a lot of determination to watch them all to the end, I suspect many will consider them a bit boring...:D  I always try to read all messages in the comments section of my videos, and I try to answer all questions if asked. I remember a Yanal Arslan in the comments, the name is similar to yours, is that you?

Link to comment
Share on other sites

On 6/6/2022 at 2:18 PM, GerardM said:

FAR from boring David a valuable source of information for violin making hacks like myself.

 

7 hours ago, David Rosales said:

Agreed. The bridge video was mesmerizing. Love the content. 

Thanks, I'm glad they can be of some use to someone:)

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.


×
×
  • Create New...