p.s.
all this talk about making a cutter, why can't someone make a stereo head that will fit a 6N?!
i love the thought of someone re-inventing the lathe. if i knew more about building one, i'd totally love to help out, unfortunately my knowledge lies in cutting a good record and my 6N only at the moment. keep the ideas flowing fellas! this thread is awesome!
p.s.
all this talk about making a cutter, why can't someone make a stereo head that will fit a 6N?!
p.s.
all this talk about making a cutter, why can't someone make a stereo head that will fit a 6N?!
all the best!
- tommie 'plan 9' emmi
poly-cut lathe cuts / cymbalism recordings
- tommie 'plan 9' emmi
poly-cut lathe cuts / cymbalism recordings
Hey Fragglefraggle wrote:mate if we really get this thing up and running than why not. Can't be that hard who wants to send me an old broken neumann head?
Neumann Head Broken send it to you? Righto! Have you seen hens teeth No!
Well they are not around mate
A broken head is repairable at an extravagant price I must say No one around has "spares" Sean and Robbie do the rewinds in Europe and a couple of fellows in the USA at around the $5-7,000 each so who is going to send you one?
The last 3 of SX 74 heads that where up for sale about 12 months ago where averaged around the $20,000 This was from a guy in New York offering two New sx 74 heads in the box and a fully refurbished one from Neumann
About a year ago a cooked sx 68 head went for $1500 US ex Deroy from Florida
Current ask for an sx 68/74 is around the $4-5,000 USD condition unknown But with cont reading of the coils, so dont hold your breath on this one
Besides if you do get one I would have thought that by the time you figured out it's construction as well as the materials used as well as sourced it would be a long long time
Talking to Robbie in Italy he suggested that it took him a couple of years to source the right flat wire that Neumann uses for the coils The adhesives so as to keep them together another long stretch
I am not suggesting that it cannot be done what I am trying to point out is that this was a process involving a very long time of research as well as development including feedback from the field so as to finish up with the likes of an sx 68 or 74 head on the part of Neumann or any one else that made a worthwhile cutter head for that matter
Vestax invested a few million for the ill fated cutter they produced The biggest head ache was the cutting head that was good for around the 100 cuts before it gave out
Which brings me to a point
If all the aspirants here put up a collective effort
(read dollars) in obtaining the manufacturing rights as well as the gear used to make this machine it will go a long way in having a very good basis for a cutting lathe with the collective effort pointed towards a good cutting head for it, as it has just about everything else sorted out within reason
Just a thought
Cheers
"The Vinyl Truth"
Chris
Chris
@ mossboss
Sometimes I like the way you say things
Straight to the point must be an Aussie thing hehe
well I cannot say you are not right.
It would be hard without proper connections anyway.
You are probably also right with the Linear motion systems.
I can imagine skf get back to me with a price of 12000 dollars or so.
But I contacted 6 different manufacturer in Europe.
Another possibility could be to buy a linear system from ebay.
I found heaps of them pretty cheap.
Than I saw the prices of new servo motors and I couldn't believe how fuc.... expensive they are but there are cheaper ones on ebay too.
One more issue would be you can't control a servo motor without a servocontroler which is bloody expensive too. ( correct me if I'm wrong)
I will have to wait untill I actually get some prices.
Can I drop in any time next week or should I give you a ring first?
Cheers mate
Sometimes I like the way you say things
Straight to the point must be an Aussie thing hehe
well I cannot say you are not right.
It would be hard without proper connections anyway.
You are probably also right with the Linear motion systems.
I can imagine skf get back to me with a price of 12000 dollars or so.
But I contacted 6 different manufacturer in Europe.
Another possibility could be to buy a linear system from ebay.
I found heaps of them pretty cheap.
Than I saw the prices of new servo motors and I couldn't believe how fuc.... expensive they are but there are cheaper ones on ebay too.
One more issue would be you can't control a servo motor without a servocontroler which is bloody expensive too. ( correct me if I'm wrong)
I will have to wait untill I actually get some prices.
Can I drop in any time next week or should I give you a ring first?
Cheers mate
just to give you some more infos.
vinylium has ,i think , all necessary spare parts for sx74 rebuilt in stock . new made.
even the torque tube, all springs, feedback coils....
they have the machine for making the EXACTLY flat wire as neumann specified.
also all the original glues, adhesives as neumann specified.
I have the original neumann spring forming tools (one of the key elements for do a rebuilt) which are used now at vinylium. these tools i recievied during my work for Richter (ex neumann) about 10 years ago.
f.
vinylium has ,i think , all necessary spare parts for sx74 rebuilt in stock . new made.
even the torque tube, all springs, feedback coils....
they have the machine for making the EXACTLY flat wire as neumann specified.
also all the original glues, adhesives as neumann specified.
I have the original neumann spring forming tools (one of the key elements for do a rebuilt) which are used now at vinylium. these tools i recievied during my work for Richter (ex neumann) about 10 years ago.
f.
Flo
Hey Flo
This is very insightful
You and Vinilium have access to the most important parts that are needed in the making of the sx heads
Thank you for the heads up
I did know that you where instrumental in making the head as it is sold today by these people also they do repairs something I failed to mention in my last post
The question I have is this, what does it cost for say an SX 74 "replica" today
Are they prepared to sell heads to suit the VMS series of lathes?
It would be good to know
But I guess if the repair cost is as high as it is why would they sell a new head at less than repair cost if at all Am I right in this?
I would have thought that at a reasonable price there would be quite a few people who would pay so as to have a spare head just in case
As an educated guess I would place a figure of around 12-15 heads world wide just as spares from people who rely on a lathe with a working head for their living
At least I would have one or two given that I do not have to Mortgage my first born or myself to pay for them
On another front Assuming that the people in this thread get their act together it seems that another 10-15 heads would be required so all up there is a real possibility for around 30-40 cutting heads which seems to me as a reasonable number for you and your friends at vynilium to mull over
What is your view Flo? Am I somewhat near the mark on Numbers? or just completely wrong or uninformed.
On another point
If this is to get any further without someone putting their hands up so as to collect prelim specs in point form it will just get very messy with repeated posts on subjects/areas that have already being covered or discussed
Also a pole on numbers by people registering their interest may be a wise move so as to asses the viability of such a project
Cheers
This is very insightful
You and Vinilium have access to the most important parts that are needed in the making of the sx heads
Thank you for the heads up
I did know that you where instrumental in making the head as it is sold today by these people also they do repairs something I failed to mention in my last post
The question I have is this, what does it cost for say an SX 74 "replica" today
Are they prepared to sell heads to suit the VMS series of lathes?
It would be good to know
But I guess if the repair cost is as high as it is why would they sell a new head at less than repair cost if at all Am I right in this?
I would have thought that at a reasonable price there would be quite a few people who would pay so as to have a spare head just in case
As an educated guess I would place a figure of around 12-15 heads world wide just as spares from people who rely on a lathe with a working head for their living
At least I would have one or two given that I do not have to Mortgage my first born or myself to pay for them
On another front Assuming that the people in this thread get their act together it seems that another 10-15 heads would be required so all up there is a real possibility for around 30-40 cutting heads which seems to me as a reasonable number for you and your friends at vynilium to mull over
What is your view Flo? Am I somewhat near the mark on Numbers? or just completely wrong or uninformed.
On another point
If this is to get any further without someone putting their hands up so as to collect prelim specs in point form it will just get very messy with repeated posts on subjects/areas that have already being covered or discussed
Also a pole on numbers by people registering their interest may be a wise move so as to asses the viability of such a project
Cheers
"The Vinyl Truth"
Chris
Chris
introducing the caruso stereo cutter head
well
this is a little bit too early. but anyway it answers most of your question.
i didnt wanted to bring it up until i have a real piece in my hands.in topics about cutterheads normally there is 95 percent rumours and 5 percent reality.... but as there is the topic actual i give a little infos.
and a preliminary render. yes it looks ugly.but it gives an idea.and it is not the most recent one...wait for the real one.and dont watch for deep details. it is not the actual cad rendering.
it is 10 years now i developped the sc-99 head. this was for kingston dubplatecutter. and later we found the quality way good enough to cut also highend records with that setup.
but time passes and now after 10 years it is time to introduce a new generation of cutterheads.
i decided to develope a new head around one year ago to bring a new generation of stereo cutting heads.. again with state of the art technology (in developement and also in used materials)
mainly because i saw people buying used grampian heads and other historcal material for $1000-1500. and sx74 going into ranges where it becomes just not affordable anymore for hobbiists.
it will be a 100 pcs edition. with an early bird series of 10-15 pcs on a preorder basis. i hope that i can produce the first 10 pcs run for us$1500 a piece. including an (opensource) pre-amp encoder- feedback pcb-board for best matching....
if i can do it for $1500 (i guess i can). will be clear in about 3-4 weeks...
here the facts so far which i can communicate.
- the caruso head is a full stereo feedback head. comparable to neumann sx74 and sc-99. the main idea is a cheap, solid and high quality head for the semi-pro user.
a selected material, professional (and sure more expensive) head on the caruso basis is in mind. but is not priority.
-parts for the prototype where ordered last week.
-in contradiction to the sc-99 head, the drive coil dimension is not neumann compatible. neumann coil is around 9mm and the caruso-head will be approx. 13mm diameter.
- thanks to a bigger drivecoil diameter i can have vented magnetic pole pieces. air compression as in westrex, neumann, or sc-99 will not occur.
-the feedbacksystem is independant to the drivecoil. that means the feedack information is taken from the torque tube. that means from the closest point to the stylus
- the heads weight is around 550-600 Gramm.solid brass body. so almost same as Neumann head. for Presto or other semi pro lathes there is an aluminum leightweight version. around 250 gramm. but for optimal bbass response a heavier head is always better.
- drivecoil nominal resistance: is 4.6 ohm
- all magnetic drive is optimised with FEM software.
- the important parts are FEM calculated for self resonances.
- du the fact that the feedbackcoil is not part of the driver system, it is planned that you can buy additional driver systems. so in an emergency you can exchange it by yourself. similar to PA HF-tweeters.
- helium cooling is possible
- the head dimensions are compatible to neumann head. approx. 72mm with. so no problem to fit on any neumann machine.
- the drive coil center springs are totally new designed. better material. different shape. therefore i can give better mechanical robustness.
- the stylusholder has neumann 1:20 shank. there will be 2 versions of cutting angle 15 degree standard laquer and 0 degree polycarbonate and DMM.
- max drivecoil excursion is +/- 200um.
- connector will be DB15
thats it for the moment.
i havent asked for a eraly-bird registration, reservation or preorders yet. i want to have the prototype in my hands. and cut first.
but if you are interested. send me a pm. i can put you on the waiting list.
in about a 45 days it becomes serious and i send details and order infos to the interested people. then i start the pre series.
f.
this is a little bit too early. but anyway it answers most of your question.
i didnt wanted to bring it up until i have a real piece in my hands.in topics about cutterheads normally there is 95 percent rumours and 5 percent reality.... but as there is the topic actual i give a little infos.
and a preliminary render. yes it looks ugly.but it gives an idea.and it is not the most recent one...wait for the real one.and dont watch for deep details. it is not the actual cad rendering.
it is 10 years now i developped the sc-99 head. this was for kingston dubplatecutter. and later we found the quality way good enough to cut also highend records with that setup.
but time passes and now after 10 years it is time to introduce a new generation of cutterheads.
i decided to develope a new head around one year ago to bring a new generation of stereo cutting heads.. again with state of the art technology (in developement and also in used materials)
mainly because i saw people buying used grampian heads and other historcal material for $1000-1500. and sx74 going into ranges where it becomes just not affordable anymore for hobbiists.
it will be a 100 pcs edition. with an early bird series of 10-15 pcs on a preorder basis. i hope that i can produce the first 10 pcs run for us$1500 a piece. including an (opensource) pre-amp encoder- feedback pcb-board for best matching....
if i can do it for $1500 (i guess i can). will be clear in about 3-4 weeks...
here the facts so far which i can communicate.
- the caruso head is a full stereo feedback head. comparable to neumann sx74 and sc-99. the main idea is a cheap, solid and high quality head for the semi-pro user.
a selected material, professional (and sure more expensive) head on the caruso basis is in mind. but is not priority.
-parts for the prototype where ordered last week.
-in contradiction to the sc-99 head, the drive coil dimension is not neumann compatible. neumann coil is around 9mm and the caruso-head will be approx. 13mm diameter.
- thanks to a bigger drivecoil diameter i can have vented magnetic pole pieces. air compression as in westrex, neumann, or sc-99 will not occur.
-the feedbacksystem is independant to the drivecoil. that means the feedack information is taken from the torque tube. that means from the closest point to the stylus
- the heads weight is around 550-600 Gramm.solid brass body. so almost same as Neumann head. for Presto or other semi pro lathes there is an aluminum leightweight version. around 250 gramm. but for optimal bbass response a heavier head is always better.
- drivecoil nominal resistance: is 4.6 ohm
- all magnetic drive is optimised with FEM software.
- the important parts are FEM calculated for self resonances.
- du the fact that the feedbackcoil is not part of the driver system, it is planned that you can buy additional driver systems. so in an emergency you can exchange it by yourself. similar to PA HF-tweeters.
- helium cooling is possible
- the head dimensions are compatible to neumann head. approx. 72mm with. so no problem to fit on any neumann machine.
- the drive coil center springs are totally new designed. better material. different shape. therefore i can give better mechanical robustness.
- the stylusholder has neumann 1:20 shank. there will be 2 versions of cutting angle 15 degree standard laquer and 0 degree polycarbonate and DMM.
- max drivecoil excursion is +/- 200um.
- connector will be DB15
thats it for the moment.
i havent asked for a eraly-bird registration, reservation or preorders yet. i want to have the prototype in my hands. and cut first.
but if you are interested. send me a pm. i can put you on the waiting list.
in about a 45 days it becomes serious and i send details and order infos to the interested people. then i start the pre series.
f.
cost of a replica sx74
chris: forgot to answer that.
sx74 has at least 200 parts.maybe more.
imagine to make exact drawings from that....that keeps you busy for a while. and even thn you are not sure to have a 100percent copy of the part.
all parts are high precision, mostly done on a lathe (decolletages) or milling machine.so your minimum order is 100-300 parts to get an intersting price..
a lot of parts are done in a way you need lot of manual work.
even material will exceed i think $5000 if you make only one or a few. plus all the work. and then if you do it the first time..experience is missing... would be a long and expensive work.
sure you can do only small numbers. but then the parts become ridiculous expensive...
so i guess this is the reason a neumann clone would come to the price of a 2nd hand head......
neumann made almost exactly 1000 heads. some more. sx74&sx68 together...a lot of sx68 heads have been converted internally to sx74 already through neumann. then all the developping time.
so they had to get back the money with repair.....
official lifetime for a sx74 was around 1-1.5 years...sometimes two years. but in a professional studio after 2 years most had to send in for service.
i also know heads not been serviced for more than 10 years..but to keep quality standart of a big record company (e.g. polygram) back in the days it was maybe 1.5-2 yeears of lifetime..
*******
about your estimations.
and the market is limited.
maybe yes 40 professional heads.
maybe 50-100 semi pro... but thats it....
an estimation of
the actual number of heads produced:
westrex heads? maybe 400-500? who can sy more to that?
neumann sx68,74: approx 1000
sc99: i guess 60-100 max
haeco sc-2 westrex clone: approx 200
ortofon heads? no idea... but max 500 i guess and up and running maybe 20
f.
sx74 has at least 200 parts.maybe more.
imagine to make exact drawings from that....that keeps you busy for a while. and even thn you are not sure to have a 100percent copy of the part.
all parts are high precision, mostly done on a lathe (decolletages) or milling machine.so your minimum order is 100-300 parts to get an intersting price..
a lot of parts are done in a way you need lot of manual work.
even material will exceed i think $5000 if you make only one or a few. plus all the work. and then if you do it the first time..experience is missing... would be a long and expensive work.
sure you can do only small numbers. but then the parts become ridiculous expensive...
so i guess this is the reason a neumann clone would come to the price of a 2nd hand head......
neumann made almost exactly 1000 heads. some more. sx74&sx68 together...a lot of sx68 heads have been converted internally to sx74 already through neumann. then all the developping time.
so they had to get back the money with repair.....
official lifetime for a sx74 was around 1-1.5 years...sometimes two years. but in a professional studio after 2 years most had to send in for service.
i also know heads not been serviced for more than 10 years..but to keep quality standart of a big record company (e.g. polygram) back in the days it was maybe 1.5-2 yeears of lifetime..
*******
about your estimations.
and the market is limited.
maybe yes 40 professional heads.
maybe 50-100 semi pro... but thats it....
an estimation of
the actual number of heads produced:
westrex heads? maybe 400-500? who can sy more to that?
neumann sx68,74: approx 1000
sc99: i guess 60-100 max
haeco sc-2 westrex clone: approx 200
ortofon heads? no idea... but max 500 i guess and up and running maybe 20
f.
Flo's Response
I thank you for that very good
Your estimates are pretty close to the mark I agree with you
Yes Neumann never made money, so the story goes out, of that division
A price of around the $20-25 K per head than seems about right given that only 1000 odd where ever made Mine is number 672 and another I have is 741 so they must be around 3/4 of the way in production
However given the length of time they where in production it is not a lot of heads on a per year basis From 1968 to around the year of 1980-81, That is 12 odd years around the 70-80 heads per year Not many than is it!
I happen to have an SX 45 head with a serial no in the 200's not many of these where made either by the sound of it
I am curious to know how many lathes where ever made by them
It has always been my view that no more than 300-400 lathes where ever produced by them any Ideas any one? Flo?
Thanks again for the input Flozki very good indeed
Cheers
Your estimates are pretty close to the mark I agree with you
Yes Neumann never made money, so the story goes out, of that division
A price of around the $20-25 K per head than seems about right given that only 1000 odd where ever made Mine is number 672 and another I have is 741 so they must be around 3/4 of the way in production
However given the length of time they where in production it is not a lot of heads on a per year basis From 1968 to around the year of 1980-81, That is 12 odd years around the 70-80 heads per year Not many than is it!
I happen to have an SX 45 head with a serial no in the 200's not many of these where made either by the sound of it
I am curious to know how many lathes where ever made by them
It has always been my view that no more than 300-400 lathes where ever produced by them any Ideas any one? Flo?
Thanks again for the input Flozki very good indeed
Cheers
"The Vinyl Truth"
Chris
Chris
-
subkontrabob
- Posts: 284
- Joined: Fri Oct 30, 2009 5:40 am
- Location: Helsinki, Finland
Re: Flo's Response
the serial number of the AM31 I've used is 234, if that helps in any way.........mossboss wrote:It has always been my view that no more than 300-400 lathes where ever produced by them any Ideas any one? Flo?
quote from orientalmotor
2 x Linerar guide with step motor and controller
1 x step motor with controler
1 x control software
6300 usd
This guy told me this would be a high precision system.
Tolerances are 0.002 mm for guides and he said the motors can be driven 0.001 mm a second.
He also said step motors are be better & cheaper than servo motors for this purpose.
Out of my price range at the moment...
1 x step motor with controler
1 x control software
6300 usd
This guy told me this would be a high precision system.
Tolerances are 0.002 mm for guides and he said the motors can be driven 0.001 mm a second.
He also said step motors are be better & cheaper than servo motors for this purpose.
Out of my price range at the moment...
@fraggle. .002mm=80 millionths inch, which is way beyond the precision needed for record-cuttting, but also it's the wrong application since it's for positioning, not feeding a linear stage at a given velocity. I think you can do for 1/10th that price or less with purchased leadscrew with engineered plastic linear bearings and dc motor with encoder. I will try to back my claim within a couple of weeks, "real" job schedule permitting...
-
dvandervort
- Posts: 3
- Joined: Sun Jun 13, 2010 12:02 pm
- Location: portland, or
- Contact:
Motor Controllers
Hello,
A friend of mine asked me about using a motor controller I developed for a different purpose for use with a record lathe. I am constantly looking for more uses for it and thought it was a cool idea. So I sketched what I see a record lathe being:
http://opencapitalist.org/content/record-cutting-lathe
(the above rendering is minus the motors, lead screw, and belt.)
This isn't really my realm, but I don't see why the cutter head isn't supported on both ends to limit deflection.
One other point - I have used ground granite as a flat surface for calibration, why not use it for the plater? Its cheap, stable, good mass, and can be ground extremely flat.
One last thing. I have used crystal positioning systems in the past. I don't think any of the cutter heads used them for modulation, but it was the first thing I thought about when someone broached this topic. I did see one blurb about why they were not suitable for this purpose but one thing that has become apparent in the very limited research I have done is that there hasn't been a lot of development in this field for a very long time. Maybe the control mechanisms weren't in place the last time someone tried to design a crystal cutter head?
Regards,
Darren
A friend of mine asked me about using a motor controller I developed for a different purpose for use with a record lathe. I am constantly looking for more uses for it and thought it was a cool idea. So I sketched what I see a record lathe being:
http://opencapitalist.org/content/record-cutting-lathe
(the above rendering is minus the motors, lead screw, and belt.)
This isn't really my realm, but I don't see why the cutter head isn't supported on both ends to limit deflection.
One other point - I have used ground granite as a flat surface for calibration, why not use it for the plater? Its cheap, stable, good mass, and can be ground extremely flat.
One last thing. I have used crystal positioning systems in the past. I don't think any of the cutter heads used them for modulation, but it was the first thing I thought about when someone broached this topic. I did see one blurb about why they were not suitable for this purpose but one thing that has become apparent in the very limited research I have done is that there hasn't been a lot of development in this field for a very long time. Maybe the control mechanisms weren't in place the last time someone tried to design a crystal cutter head?
Regards,
Darren
better living through open source.
dvandervort
Hey welcome on board, by the way enjoy the good stuff
Ok first things I followed the link but got no where it is asking me to log in with user ID or open ID is this right?
On another point There was a lot of crystal cutter heads made in the past for lower cost machines
Astatic made a whole lot of them which where used by manufacturers of lathes as an OEM part
It seems as you say that no development has taken place for many years now around the 35 if I take a guess
May be you are right on the development front about crystal as a transducer it is not a new idea however there was never in to my knoweledge any crystal cutting heads used by the respected cutting houses although I have heard records which no doubt where cut on a very low quality lathe and most likely a crystal head
Agree on the granite stuff good idea a lot of audiophiles use them on their turntables
Keep in mind that it has to have some vacuum so as to suck down the lacquer as its been cut so a bit of drilling would be required
No big deal really and the adhesives to day are fantastic
So one can do all the machining on a steel plate and glue the lump of granite on top or better still make a sandwich with an alluminium top
May be also incorporate a heating element steel bottom for bearings etc as well as a couple of brushes so as to supply low current to the heater
The concept sits good with me any way
Keep posting man it sounds good
BY the way if you where to concentrate on anything do it for the T/T and head transport mechanism
There is a member here who would provide cutting heads shortly
He goes by the name of Flo so check it out
Cheers
Ok first things I followed the link but got no where it is asking me to log in with user ID or open ID is this right?
On another point There was a lot of crystal cutter heads made in the past for lower cost machines
Astatic made a whole lot of them which where used by manufacturers of lathes as an OEM part
It seems as you say that no development has taken place for many years now around the 35 if I take a guess
May be you are right on the development front about crystal as a transducer it is not a new idea however there was never in to my knoweledge any crystal cutting heads used by the respected cutting houses although I have heard records which no doubt where cut on a very low quality lathe and most likely a crystal head
Agree on the granite stuff good idea a lot of audiophiles use them on their turntables
Keep in mind that it has to have some vacuum so as to suck down the lacquer as its been cut so a bit of drilling would be required
No big deal really and the adhesives to day are fantastic
So one can do all the machining on a steel plate and glue the lump of granite on top or better still make a sandwich with an alluminium top
May be also incorporate a heating element steel bottom for bearings etc as well as a couple of brushes so as to supply low current to the heater
The concept sits good with me any way
Keep posting man it sounds good
BY the way if you where to concentrate on anything do it for the T/T and head transport mechanism
There is a member here who would provide cutting heads shortly
He goes by the name of Flo so check it out
Cheers
"The Vinyl Truth"
Chris
Chris
Re: Motor Controllers
Hi Darren,dvandervort wrote:Hello,
One last thing. I have used crystal positioning systems in the past. I don't think any of the cutter heads used them for modulation, but it was the first thing I thought about when someone broached this topic. I did see one blurb about why they were not suitable for this purpose but one thing that has become apparent in the very limited research I have done is that there hasn't been a lot of development in this field for a very long time. Maybe the control mechanisms weren't in place the last time someone tried to design a crystal cutter head?
Regards,
Darren
I've been thinking about experimenting with a PZT element head design. How hard would it be to get deflections of up to +/- .003" with a PZT element? I suspect you would have to couple the PZT to a lever of some sort to increase defection. Would this end up lowering the mechanical impedance as seen at the stylus and lower the system resonsance? As I understand, piezo positioning systems are used for very small deflections.
Mark