Sign in to follow this  
skiingfiddler

Suspension systems in violin cases

Recommended Posts

If I look at the suspension systems that occur in 3 of the better, mid range cases on the market (cases at about $500), I see 3 different approaches, or philosophies, to suspending the instrument, ie, to the idea that the back of the instrument should be elevated above the bottom of the case. These 3 different approaches are realized in the materials used for the case suspension blocks which lie under the top block (and neck button) and bottom block of the fiddle.

These three approaches are (specific for the cases I'm looking at, with all measurements being approximate):

1. Non-collapsible block types: The top block in the case (the suspension block under the neck button and top back of the fiddle) has two layers, a 27 mm hard block with no give in it (probably made of solid wood), with an 11 mm fairly soft, spongy layer on top of the hard block for a total of 38mm of elevation above the case bottom. The bottom block in the case is a 10 mm hard block with 3 mm of fairly soft spongy layer on top of the hard block.

With this type of suspension blocks, there's no way, short of an impact that destroys the case and fiddle totally, that the back of the instrument will ever get close to touching the bottom of the case. The hard block components of the suspending blocks will not allow for top and bottom suspending blocks being compressed to less than 27 and 10 mm, respectively.

This absolute limit to compression, which keeps the fiddle at a considerable distance above the bottom of the case, no matter what, may be the primary advantage in this type of suspension.

2. Collapsible block types: The top and bottom blocks have a very thin (2 to 3 mm) hard, non-compressible layer at the bottom of the blocks while most of the block is a single layer of fairly soft, spongy material, that compresses almost completely if enough finger pressure is put on it. The top block is 27 mm high, in total; the bottom block, 17 mm.

This type of suspension would, I think, allow for more travel, up and down, of the instrument within the case than Type 1 above would, and thus Type 2 might be gentler on the fiddle in terms of the everyday bumps and jostiling a fiddle case might encounter.

It might be, however, that Type 1 would be more protective in that seldom-encountered, near catastrophic, really hard crash.

3. Semi-collapsible block types: The top and bottom blocks are made of one uniform material, a very dense, somewhat pliant foam. This foam is not as pliant as the foam in Type 2, but it is not a solid block as occurs in Type 1. The blocks in a specific case measure 27 mm and 25 mm in height, top and bottom blocks, respectively.

This type of block cannot be compressed to near flat. With very firm finger pressure, I was able to compress the top block to 18 mm from its original 27 mm, and thus this Type 3 block has that advantage over Type 2 of not being fully collapsible. At the same time this block type does not abruptly change from an area of soft travel to a area of no further travel, as Type 1 does. Its resistance to further compression would build gradually as compression occurred.

If this block (Type 3) has a disadvantage, I don't know what it is.

I'd be interested in posters' thoughts about suspension systems.

Share this post


Link to post
Share on other sites

Excellent topic and you pose a very interesting question!

Am anxious to hear the responses.

Sadly, I have no answer --just more questions:

1) How does the clearance of the back of the scroll to the inside of the case backs compare under full compression of the upper cushion? Particularily on No. 2 "Collapsible" suspension cushion.?

(Hopefully all three provide substantial and adequate clearances---- whatever "adequate" is. )

2) Besides protecting the neck, what other major benefits does full suspension provide to the violin?

Share this post


Link to post
Share on other sites

Jimbow,

Concerning clearance of scroll, it so happens that in the specific Type 2 case I have in front of me the scroll clears the bottom of the case by only a little bit, maybe 4 mm, when the suspension system is not stressed, not compressed. In the other 2 cases I have in front of me (Type 1 and 3) the scroll, in the unstressed position, is considerably higher off the bottom of the case.

If the suspension blocks in my specific Type 2 case were stressed and compressed, that would only make the danger to the scroll and neck worse. (I assume that the danger here is that the scroll, receiving a strong bump, would act as the end of a lever (the neck), breaking neck off from fiddle back.)

As you suggest, the type of suspension block and the elevation of the scroll in an unstressed suspension system are independent. You could have very high Type 2 blocks which, when not stressed (not compressed) would elevate the scroll quite a bit, while very low Type 1 blocks would elevate the scroll not as much, but the low Type 1 blocks would never allow the scroll to contact the bottom of the case, when stressed, while the very high Type 2 might.

Concerning your second question, the area that suspension protects is the sound-post area of the back. In an unsuspended case the back of the fiddle, and thus the end of sound post, rests on the bottom of the fiddle case. If the bottom of the fiddle case were to receive a hard knock near the sound post area, that force would be directed to the sound post which could push upward with enough force to split the top at the sound post.

In a suspended case, any blow to the bottom of the case at the sound-post area would not be directed at the sound post but would be directed, in a cushioned manner, by the suspension blocks to the upper and lower blocks of the fiddle, the sturdier areas of the fiddle.

Share this post


Link to post
Share on other sites

I'd be most concerned about those wimpy pads on the top of the case. Most are very compliant, allowing the bridge to hit the top of the case with a fairly low impact. I consider this to be most vulnerable area of the instrument.

On my shipping cases, I always replace this with something much firmer, but also with more accurate dimensions so it won't push down too hard on the tailiece area. Still, the lid requires pressure to close.

Share this post


Link to post
Share on other sites

I am no expert on cases but do have some opinions and want to learn more.

My absolute favorite case is my FEL Chambord which has a padded neck support along with conventional soft pads under the upper and lower block areas. I cannot find a current source.

This is a closeup view of the neck support.

dscn0868hq7.jpg

This is a view of the pads.

dscn0866wd1.jpg

I also have a number of Shar cases which I like very much. This Passport case, however, has an upper block support but no padded neck support. I am not sure this is a problem but the FEL does seem to provide superior neck support.

dscn0869qf3.jpg

Any opinions?

Anyone know where I can obtain another FEL Chambord?

Jimbow

Share this post


Link to post
Share on other sites

I like the look of the Chambord a lot. I've never heard of them. Is this vintage? Are they still being made?

The biggest problem I've seen in cases with suspension is where the neck block holder is actually so firm and so high that the button suspension is not giving any support at all. Seems to me the bottom pad should be firm, the top pad should be higher, but more flexible, and the neck rest should be completely soft.

From the looks of the Chambord, there's an interesting cantilever action. There are two pads (most cases only have one) on the lid. One presses down on the chin rest. The other on the top of the scroll. If this is properly dimensioned it should result in completely immobile violin. Without the neck ties that most cases now use.

Share this post


Link to post
Share on other sites

Expanding the discussion of suspension to the padding that pushes down on the fiddle as well as the blocks that hold the fiddle off the bottom of the case is a sensible step forward.

While I understand David's complaint about wimpy pads in the case lid which aren't doing their job of holding the violin down, I most often have just the opposite problem. In most of the less expensive cases I've tried ($200 or less), that pad in the case lid that would press down on the part of the chinrest directly over the tailpiece is too stiff for my rather high chinrest. The pad would not have enough give.

My chinrest, a medium high SAS, has its cup above the tailpiece at about 34 mm above the violin table edge. That's about 10 mm higher than the hump over the tailpiece of a Guarneri style chinrest is. Usually, on cheaper cases, closing the lid with a stiff pad onto my high chinrest requires more force than I want to put on the fiddle. (The overall effect is the same as overtightening a chinrest.) So, I have pulled out of a case one such very stiff pad and replaced it with a mushier piece of foam.

Given David's warning, I'll be careful that the foam isn't too mushy.

I really haven't had the problem of an overly stiff lid pad occurring in better cases (around $500). The pads haven't been overly wimpy either, but then I have those very high chinrests taking up a lot of vertical room.

If Falstaff hadn't pointed out that there are two lid pads in Jimbow's case, I wouldn't have seen them, but there they are, and I've never seen anything like it. Looks like a good idea for those people who might forget to fasten neck straps.

I agree with Falstaff's warning against having the neck perched on a block which is so high that the upper block area of the fiddle is elevated above the padding it's supposed to sit on. Given that warning, I would think Jimbow need not worry about the lack of support for the neck in his Passport case. If you have to choose between the fiddle being supported only at the upper block area of the fiddle or being supported only somewhere along the neck, instead, I'd choose support at the upper block area.

Ideally, you might get a support arrangement where the fiddle upper block area, neck button, and neck at its curve down to the neck root are all supported with equal force, by one continuous block formed to match those varying heights and contours. The Type 3 block I mentioned in the original post does that, from what I can see.

Share this post


Link to post
Share on other sites

I was involved with a case manufacturer in the design of some of the first suspension cases. We came up with things that worked very well, but many things were ultimately changed for production and mass marketing reasons. For example, less compliant instrument supports at the upper and lower blocks on the back protected the instrument much better, but customers prefered a more cushy feel.

The biggest compromise was the support in the lid, and it was partly done so it would fit a large variety of instrument and chinrest combinations. It's still the weakest link in most cases, and I'm saying this having done the tests to back it up.

The best thing might be to replace this pad with a dual density one that's custom made. Use a high durometer (stiff) foam (even styrofoam) cut to a size so that it almost touches the tailpiece or chinrest. Take up the remaining space with a much more compliant foam. This will prevent the instrument from moving much, even with a severe impact, but also won't put significant pressure on it when the lid is closed. If you want it to look good, often you can find similar fabric at a fabric store to cover it with, or you can order a spare blanket and use the material from that.

Sorry, but beyond a certain point, cases must be customized for best protection.

The best intentioned case maker can't cover all scenarios because the chinrest, neck angle and scroll dimensions vary from one violin to the next. Violas are even more problematic.

Another potential area of concern is whether the scroll can come in contact with the back of the case. If you can push down mildly on the upper block area and have the support compress enough that the scroll hits, the instrument is at risk of the neck breaking out of the instrument, often taking the button with it. Sometimes this upper block pad can be separated from the case easily with a table knife. A cardboard or wooden shim can be placed underneath, and everything glued back together. If the shim isn't very thick and is recessed somewhat, it won't even show.

Share this post


Link to post
Share on other sites

Hi Skiingfiddler,

I'm not sure whether your "Type 2" or "Type 3" foam descriptions employ a viscoelastic foam.

For my next violin case, I'm looking for a hardshell case with a minimum 1-inch thick high-density "viscoelastic foam" [also known as 'memory foam' as in Tempur-Pedic mattresses] used at the critical suspension locations [scroll, neck-button, bottom, endpin, chinrest].

The case may employ "harder" polyurethane foam elsewhere, but 'thick' viscoelastic foam at the critical suspension locations is a "must".

Just my $0.02 worth.

Best wishes,

Jim

Share this post


Link to post
Share on other sites

quote:


Originally posted by:
JimMurphy

I'm not sure whether your "Type 2" foam description is a viscoelastic foam. If so, 2 to 3 mm would be much too thin to serve as suitable suspension.

Jim

Hi Jim,

That 2 or 3 mm at the bottom of the Type 2 suspension pads isn't foam at all. It's some kind of very thin material, maybe cardboard, wood, or hard plastic, that is there, I think, more to give a base to glue the pad to case, rather than contribute to the mechanics of the vertical compression of the pads.

The Type 2 pad is a rather thick pad (27 mm thick at the upper block area in the case I'm using as a Type 2 example) made up of fairly spongy foam (don't know whether that's viscoelastic foam). The resting weight of the violin itself will not noticably compress that pad, but finger pressure applied directly to the pad will compress it rather easily. And very firm finger pressure will compress it down to a few mm. (Now that I think of it, maybe that's the 2 or 3 mm of foam you had in mind.)

Share this post


Link to post
Share on other sites

Hi skiingfiddler,

You can usually identify viscoelastic foam by applying direct finger pressure. The spongy viscoelastic foam will compress easily, then springback to its normal uncompressed thickness moments after finger

pressure is released.

Viscoelastic foam is manufactured in many thicknesses although only in large standard sized sheets which means a violin case manufacturer needs to cut the foam down to size/shape.

Jim

Share this post


Link to post
Share on other sites

As skiingfiddler and some other members know I have spent the last 3 years developing a range of carbon fibre cases for guitars and violins.

Here is a photograph of a test rig which gives you a rough idea of the basics of our suspension system

For the two base suspension pads shown we have opted for what skiingfiddler calls type 3 foam. This is high quality closed cell foam called Alveolit - technically it is a physically crosslinked, closed cell polyolefin foam. We have chosen this for exactly the reasons skiingfiddler describes in his original post.

You can see from the photograph that the size and layout of the pads means there is plenty of room below the scroll and no amount of pushing would bring it into contact with the case. The clearance below the case is a minimum of approximately 10mm, the clearance above the bridge is the same.

Because of the great rigidity of the case's carbon fibre shell we are confident of the level of protection this will provide. We shall be testing the cases at the University of Plymouth here in the UK to measure the weight that the case will bear before the carbon deflects enough to touch the bridge.

We considered the viscoelastic 'memory foam' mentioned by Jim Murphy and decided that it is an expensive route which does not seem to offer the same level of protection. Memory foam was developed for pillows and mattresses so is designer to mould to a shape and was not intended as a shock/impact absorbtion material. Closed cell foam of the type we use is designed more for the purpose of protection.

David Burgess I was very interested to read of your case design experience and your points about needing to tailor make the pad in the lid fit with my conclusions. Although it is tricky to take exact measurements of the thickness of the neckrest we will ask our clients to send us the best measurement they can. We will make up the lid pads in a way similar to your description - with our closed cell foam forming the main body of the pad and a much softer more compliant foam forming the last 10mm or so.

Our design for the suspension pad under the upper block is a very simplified verion of the one shown in the Chambord case - combining support for the block with a shaped piece which will prevent side to side movement of the violin body. The only contact between the suspension and the neck will be immediately around the block where there is greatest strength.

I hope this adds to the debate - I'd welcome any comments or feedback about the system I have described.

Nick

For those that are curious you can read more about our cases on our blog

Share this post


Link to post
Share on other sites

quote:


Originally posted by:
David Burgess

I was involved with a case manufacturer in the design of some of the first suspension cases. We came up with things that worked very well, but many things were ultimately changed for production and mass marketing reasons. For example, less compliant instrument supports at the upper and lower blocks on the back protected the instrument much better, but customers prefered a more cushy feel.


Another compromise (witnessed within the same company as David is referring to), which results in what I feel is a weak link, is the flat bottom (back) side of most cases. An arch (as is usual in the lid) is much stronger than a flat panel, and we designed one with this feature (testing was fun... we jumped all over the thing; strong as heck). It's, unfortunbately, also a little more expensive to produce. Another advantage (besides strength) was that it allowed plenty of clearance for the fiddle in the bridge area while it yielded lower (thinner) sides... so the look was sleek. A downside was that many players found that an arched back case wasn't as stable when open on a flat surface (especially when the lid is crammed with music). It tended to tilt backwards. The suspension system relied in a neck tie-down and endblock pad. The case was in production for a few years, but is no longer made. I have one of the prototypes that I'm very comfortable shipping instruments in.

Share this post


Link to post
Share on other sites

Nick, the photo looks good, except maybe for the "lid" support coming down onto the fingerboard.

Potential problems:

The button area (the lowest point where the neck attaches) is already under tension due to the strings. The fingerboard is a pretty long lever, and and if the case were dropped on the top, it might apply quite a bit of force at this joint.

Also, if the pad on the top applys any downward force when the lid is shut, it might eventually warp the fingerboard.

How about two pads instead, one over the heel of the neck, and the other over the lower block area?

I like the idea of a pad(s) keeping the entire instrument away from the top of the case though, in case someone forgets to fasten a neck restraint. I've had people forget when shipping violins, so most of my shipping cases are set up this way.

Share this post


Link to post
Share on other sites

quote:


Originally posted by:
David Burgess

Nick, the photo looks good, except maybe for the "lid" support coming down onto the fingerboard.


Agreed.

Seems to me I've seen a system (Gewa/Jaeger?) that uses a crescent shaped pad that sits closer to the upper block and a lower pad at the chinrest... I think some of their cases may have no tie-in at all...

Share this post


Link to post
Share on other sites

Thanks for that link, a little.

Surely there's more information somewhere about these cases. Who is FEL? Where are they made? Surely someone else besides Zoller-Levy distributes... I'm interested.

Jimbow, can you tell us any more about your case? More photos?

Share this post


Link to post
Share on other sites

Hi falstaff,

I am pleased you like my Chambord case as I admire your well established good taste from following your posts.

In checking my (random filed) records, I bought the case in 1994 from Discount String Center in South Bend, Indiana. It was offered at a catalog discount sale since they were discontinuing as I recall.

The invoice description is "CS Chambord VI case brown/olive".

This photo shows the bottom block pad which is about 1/4 inch thick.

dscn0873iv7.jpg

The top block pad is about 1 inch thick as shown here.

The neck support cradle has about 1/4 inch pad. Notice also the soft padding surrounding the ribs.

dscn0871qi2.jpg

Both upper (lid) pads are about 2 inches thick and are very soft foam (as are all the pads)

There is one over the bottom block and one over the scroll, as you detected on the previous set of photos.

dscn0872uf4.jpg

The silk plush lining is padded on the bottom with about 1/8 inch soft foam.Overall the effect is pillow soft luxury completely surrounding and protecting the violin. Ah, those French!

The case exterior is of modern design, not 'vintage', with Cordura cover, zippered top music pocket, etc. It was moderately priced.

I cannot comment on the protection provided as it has never been out of my shop and certainly not dropped or abused.

Hopefully someone here can find out more about this French FEL company and their products.

Jimbow

Share this post


Link to post
Share on other sites

Hi David Burgess

The photograph is misleading you into thinking there is a top suspension pad coming onto the finger board - there is NOT a pad there - what you see is a piece of white material that is in the bottom of the test rig.

I am still debating on whether to have a double top block which goes on either side of finger board just at the heel of neck - or a neck strap. Clearly the former has the advantage that hold the violin securely and does not depend upon the owner having to do anything except close the case. The disadvantage is that it introduces two more points of contact between case and instrument.

My inclination is towards the neck strap as I believe that offers better protection.

We looked at building our cases with slightly concave top and bottom for better strength. In the end we opted for straight sided cases as the carbon fibre gives us so much rigidity and a straight sided case is just that bit more compact and easier to pack.

Share this post


Link to post
Share on other sites

To find the products from FEL (France Europe Lutherie) or the

distributors you may try to contact them directly. The company

don't seems to be always really professionnal in the way they are

doing business, but they offer nice cases.  They also sells

violins, accesories, tools, etc...  I think that they only

sell to violin maker shops or distributors and not directly to

the customers.

France Europe Lutherie

B.P. 5

1, Route du Peu

41400 Monthou sur Cher

France

Gesch. 33 254 /714326

Fax geschäftl.: 33 254 /713067

E-Mail: france-europe@wanadoo.fr

Share this post


Link to post
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...
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.