How to reverse engineer a miniature engine casing

[OMERYOUNOS]

How to reverse engineer a miniature engine casing.I want to model in Pro/e .I ve heard the best solution is either to use CMM or scanner to take the dimensions.Does anyone can explain the scanner or CMM method.By the way it is a single cylinder ,two stroke glow ignition engine.
Thanks.

 

[raminder]

Hello OMERYOUNOS ,
I have lots of experience in Reverse Engineering. My advice to you is not to use Pro-E to reverse engineer. It gives bad results. The best tool to use is IDEA-S Imageware Surfacer Software.
The scanning can be done two different ways. Either by contact probe such as CMM or Faro Arm or by non contact scanning process like Steinbichler or Cognitens.In a non Contact Scanning system you get a dense point cloud with which you can cut section and draw curves and then make surfaces and finally a solid model. I hope that answers your question.

 

[butelja]

There is a magazine devoted to prototying and reverse engineering called Time Compression Technologies. If you work in the field, you can get a free subscription. The web address is:

http://www.time-compression.com/x/user_default.htm

 

[Rentapen]

Use what ever software you have. Coordinate measure machine and Profile numertric scanners is just a lazy way of using a vernier. You dont do much work other then placing you part on a surface and touching each area to record the placement, hard for recording small inside casting radius and the like but basic.
The rentapen

 

[Hush]

I can't remember the name of the compound, but when I was doing alot of R&D work (rip-off & duplicate) we used to use a semi-flexible elastomer that you poured over the sample, allowed to harden, then peeled it or cut it off & sectioned it. The sections could then be easily measured or placed on a grid and scanned.

Hugh

 

Wow!
You guys live hard lives. A glow engine will be very geometricly primitive. The size will allow you to use "addition cure" silicones for casting internal passages etc. PAPER WRAPPED AROUND THE INSIDE OF THE CYLINDER AND SPRAY PAINT misted (not heavy!!!) up the passages will give you an accurate lay-out of the ports... Sure, you can worry about the bend radius being off by 1/2 the thickness of the paper...

Almost all the rest should be easily done in an afternoon with dial calipers! A height gauge might be nice, but seriously, it's going to be circles!!! Port flow paths can be approximated - they were the first time in a glow engine...

Larry

 

[SnowCrash]

Ha! trying to steal some model airplane engine design, eh?
Well, as they say, "rots of ruck, fry boy!" Tolerances and materials will be more of a problem than nominal dimensions.

Be sure you take careful measurements of the bore diameter at several intervals and check for roundness. Surface finish will be important too. And remember, with a 2-cycle, timing is everything.

Crashj 'junior birdman' Johnson