Ye Olde Rocket Forum

Go Back   Ye Olde Rocket Forum > Semroc > SAM - Semroc Astronautic Modeler Team
User Name
Password
Auctions Register FAQ Members List Calendar Today's Posts Search Mark Forums Read


Reply
 
Thread Tools Search this Thread Display Modes
  #11  
Old 12-02-2012, 10:12 AM
Carl@Semroc's Avatar
Carl@Semroc Carl@Semroc is offline
Junior ??? Rocketeer
 
Join Date: Mar 2005
Location: Knightdale, NC
Posts: 1,470
Default

There are several reasons we have not released this designer to the "world". There are no checks to make sure a given cone can even be turned by us. The overall length is limited by the lathe, currently to about 11.7" useful length. The overall diameter limited by balsa, currently 2.84". The most complex check that is not done is whether the tool will hit the balsa on undercuts, knocking the piece out of the lathe.

We use the designer program on all our nose cones, but we wind up trying a questionable piece before releasing it. We don't try it unless we expect to sell enough to cover the loss of balsa and time testing it. This is not feasible for custom cones.

The other part that is missing is a release protocol. Once a design is finalized and is not going to change any more, we lock it and make no further modifications. We have cut several custom parts to find that what we cut was changed after we cut the part, but before it was received by the customer. In other words, we need to add the capability that once a customer designs a cone, "releases" it, and orders it using a particular part number, we can cut that part AND an exact replacement for that part ten years from now or one day from now. There must be an agreement about what a particular part actually looks like.

Another issue is sizing the finished cone. We size each cone with CA reinforced tubes to make sure it is the correct fit. We use the "Series" box to size the cones. So if the box designates BT-70, we expect the shoulder to fit a BT-70 so we know it is correct after we turn it. Several of the nose cones designed do not have matching shoulders and "Series". Some have diameters that do not match standard tubes. We could measure them with calipers, but that is not as good as actually trying them in a tube.

Yet another factor is balsa cost. We used to keep a wide assortment of balsa sizes in inventory, so we could cut any size balsa part on demand. Balsa has gone up 250% since we started back in 2002 (1025% since 1968!), so we do not keep much balsa in stock beyond our immediate needs.

All this said, we do a few custom parts, but on a time available basis. We charge the same for custom and standard parts, so we know we cannot make money doing custom. They are done when and as we can, as a service for our customers, not to make a business of it. BMS and Gordy have much better business models for full custom parts!
__________________
Carl McLawhorn
NAR#4717 L2
semroc.com
Reply With Quote
  #12  
Old 12-02-2012, 12:27 PM
mooshake's Avatar
mooshake mooshake is offline
Senior Rocketeer
 
Join Date: Dec 2011
Location: Lititz, Pa.
Posts: 12
Default

Quote:
Originally Posted by Carl@Semroc
There are several reasons we have not released this designer to the "world". There are no checks to make sure a given cone can even be turned by us. The overall length is limited by the lathe, currently to about 11.7" useful length. The overall diameter limited by balsa, currently 2.84". The most complex check that is not done is whether the tool will hit the balsa on undercuts, knocking the piece out of the lathe.

We use the designer program on all our nose cones, but we wind up trying a questionable piece before releasing it. We don't try it unless we expect to sell enough to cover the loss of balsa and time testing it. This is not feasible for custom cones.

The other part that is missing is a release protocol. Once a design is finalized and is not going to change any more, we lock it and make no further modifications. We have cut several custom parts to find that what we cut was changed after we cut the part, but before it was received by the customer. In other words, we need to add the capability that once a customer designs a cone, "releases" it, and orders it using a particular part number, we can cut that part AND an exact replacement for that part ten years from now or one day from now. There must be an agreement about what a particular part actually looks like.

Another issue is sizing the finished cone. We size each cone with CA reinforced tubes to make sure it is the correct fit. We use the "Series" box to size the cones. So if the box designates BT-70, we expect the shoulder to fit a BT-70 so we know it is correct after we turn it. Several of the nose cones designed do not have matching shoulders and "Series". Some have diameters that do not match standard tubes. We could measure them with calipers, but that is not as good as actually trying them in a tube.

Yet another factor is balsa cost. We used to keep a wide assortment of balsa sizes in inventory, so we could cut any size balsa part on demand. Balsa has gone up 250% since we started back in 2002 (1025% since 1968!), so we do not keep much balsa in stock beyond our immediate needs.

All this said, we do a few custom parts, but on a time available basis. We charge the same for custom and standard parts, so we know we cannot make money doing custom. They are done when and as we can, as a service for our customers, not to make a business of it. BMS and Gordy have much better business models for full custom parts!



So what you're saying is I should stick with the parts you normally offer? If I wanted a TA520 ogive transition instead of a cone transition, unless you find it to be something you will have great demand for you are not interested in turning it for me? Even if I paid extra? Or would that extra be so prohibitively expensive to compensate you for all the time to set up the lathe that I wouldn't be able to afford more then one or two pieces at a time.
I guess I really don't understand how much programing and setting up it takes to turn a part.
Are there any parts of the ones I have on the custom balsa parts list under SAM #0231 that you can and would like to turn for me? If so send me an email as to what I owe and I'll send a check. If there isn't anything you can turn then delete them off the parts list and I will have to go with what you normally have in stock. Thanks.
__________________
Rick Hackman
NAR #36359
SPAAR #503
SAM #0231
Reply With Quote
  #13  
Old 12-02-2012, 01:14 PM
sandman's Avatar
sandman sandman is offline
Custom Cone, Kit & Decal Maker
 
Join Date: Mar 2005
Location: Way North of Detroit
Posts: 4,960
Default

Carl and I are not in any kind of direct competition when it comes to custom parts.

On the contrary we tend to compliment each other on custom work.

Set-up is the problem.

Carl used a CNC set-up for his turnings. That requires a basic CAD vector for the machine.

With the arrangement that Carl has, once the set-up for the lathe is completed he can make a bunch of parts identical. That kinda make it cost effective.

But to ask Carl to do the set-up for a one off custom part well, that's NOT cost effective to him.
He'll do it but he's losing money/time.

I on the other hand, do parts one at a time with a caliper, ruler and pencil marks on the part.

Quite a bit more primitive than Carl's equipment but there is very little "set-up" time involved. Although I always do a CAD drawing.

I also am not constrained by balsa density and selection. Carl's equipment is.

Basically, Carl can do very precise consistent work on part. He can easily make a lot of parts exactly the same. I find it very difficult to get two or three parts made all exactly the same.

I can also use various other materials like hardwoods, exotic woods (if I can get them) even foam/fiberglass.

I know Carl doesn't charge that much to make one custom part but honestly with the set-up time he isn't charging what it cost him to make just one.

I send people to Carl for some work and he send people to me.

Heck, even Bill S. at BMS sends people to me.
__________________
"I'm a sandman. I've never killed anyone. I terminate runners when their time is up." Logan from "Logan's Run"

http://sandmandecals.com/
Reply With Quote
  #14  
Old 12-02-2012, 02:44 PM
RandyT0001's Avatar
RandyT0001 RandyT0001 is offline
NAR Lifetime Member
 
Join Date: Jul 2009
Location: In a state of confidence
Posts: 266
Default

Sandman,

Could you use RocSim generated csv and/or svg files to turn a custom NC?

The whole NC including shoulder is about 48" long and 7.68" in diameter (sized to fit LOC tubing).
__________________
Mid-South Rocket Society

NAR Level 1 - 3/12/11
NAR Level 2 - 4/9/11

Last edited by RandyT0001 : 12-02-2012 at 02:44 PM. Reason: Not sayin' :P
Reply With Quote
  #15  
Old 12-02-2012, 05:01 PM
sandman's Avatar
sandman sandman is offline
Custom Cone, Kit & Decal Maker
 
Join Date: Mar 2005
Location: Way North of Detroit
Posts: 4,960
Default

Quote:
Originally Posted by RandyT0001
Sandman,

Could you use RocSim generated csv and/or svg files to turn a custom NC?

The whole NC including shoulder is about 48" long and 7.68" in diameter (sized to fit LOC tubing).


Yes that will work for me. Or better just send me the rocsim file.

I will have to add an extension arm on my lathe since it has a maximum length of 34" but I've don that before.

The other problem is temperature. My shop isn't heated except for a small space heater. Not for me but for the part.

I assume this will be fiberglass over foam, The epoxy is very temperature sensitive.

The colder it is the longer it takes to cures.
__________________
"I'm a sandman. I've never killed anyone. I terminate runners when their time is up." Logan from "Logan's Run"

http://sandmandecals.com/
Reply With Quote
  #16  
Old 12-20-2012, 06:38 PM
mooshake's Avatar
mooshake mooshake is offline
Senior Rocketeer
 
Join Date: Dec 2011
Location: Lititz, Pa.
Posts: 12
Default

Carl, Sheryl since I have your designing software and you are unable to turn parts for me unless it's a large volume order or you have a lot of sale for it, Gordon Agnello told me he can. If I were to use your software to make the design I want, print it out, scan it and email it to him he could just plug the numbers in his lathe and turn my part/s. Now if I'm using your software should I pay you something for the service? If so how would a percentage/part/s turned, using his price for the basis of that percentage? For example if I paid 5% and I ordered $100.00 in parts from Gordon, I would then send you $5.00 for the use of your software.
__________________
Rick Hackman
NAR #36359
SPAAR #503
SAM #0231
Reply With Quote
  #17  
Old 12-21-2012, 06:08 PM
Carl@Semroc's Avatar
Carl@Semroc Carl@Semroc is offline
Junior ??? Rocketeer
 
Join Date: Mar 2005
Location: Knightdale, NC
Posts: 1,470
Default

Rick,
You do not owe us anything! It's just a program.
__________________
Carl McLawhorn
NAR#4717 L2
semroc.com
Reply With Quote
  #18  
Old 12-22-2012, 01:50 AM
mooshake's Avatar
mooshake mooshake is offline
Senior Rocketeer
 
Join Date: Dec 2011
Location: Lititz, Pa.
Posts: 12
Default

Quote:
Originally Posted by Carl@Semroc
Rick,
You do not owe us anything! It's just a program.


Thanks Carl.
__________________
Rick Hackman
NAR #36359
SPAAR #503
SAM #0231
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump



All times are GMT -5. The time now is 09:58 AM.


Powered by: vBulletin Version 3.0.7
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Ye Olde Rocket Shoppe 1998-2021