Ye Olde Rocket Forum - Motor manufacturing equipment

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Motor manufacturing equipment

Here's a topic I think we're all interested in to one degree or another. We've all heard about the famous (or infamous) MABEL and her siblings and decendants. Reading Carl's interview in LAUNCH, we get another glimpse into the background of the equipment itself, when he describes SEMROC's first machine. The mechanism is air-driven, one supposes due to the need to eliminate sparks that might otherwise be created from electric motors.

What else is involved? For example: How do the separate powders get put into the paper cylinder? How do the cylinders move from one step to the next? How are the cylinders fed into the machine? How are the pressing rams powered? Pneumatic or hydraulic? How do you print the various nomenclatures onto the cylinders?

I, for one, would be very interested in knowing this, just for the sake of having a better understanding...

That is a lot of questions!

To listen to Vern (and Gleda) describe the original Mabel was very exciting for me. It was so different from our machine. Vern was a master of fluid logic design. The original and probably its siblings used no electricity at all. It was all hydralic rams and valves. Even the switches were valves.

We started with hydralic and quickly moved to air. The red hydralic stains were a real nuisance, but the real problem was with speed. Air moves much faster than hydralic fluid. When I asked Vern how he moved the ram so fast (to complete one cycle in 5.5 seconds), he almost matter-of-fact said he moved it down until it hit resistance with a high volume, low pressure supply, then switched it over to a low volume, high pressure supply to do the final pack. Once it hit the pre-set pressure, it switched back over to a high volume, low pressure to move the ram back out of the way. THAT is something that I did not think of. Vern was a genius!

I am not sure what the level of interest in actual engine machine design is.

Quote:

Originally Posted by CPMcGraw

Here's a topic I think we're all interested in to one degree or another. We've all heard about the famous (or infamous) MABEL and her siblings and decendants. Reading Carl's interview in LAUNCH,...

STOP! When did the new Launch magazine go out? I havn't rceived mine yet. 'Course it'll probably show up today now that I've asked, buit JIC....

Sean

Quote:

Originally Posted by Carl@Semroc

I've always had an interest in mechanical design, even as a kid. When I first heard about MABEL it struck a chord, and I have wanted to learn more about how it worked ever since. Now I've learned something about two different machines. Yours was pneumatic, and Vern's was hydraulic.

One day I might surprise you; I might even surprise myself...:eek: :cool: :rolleyes:

Sorry for my ignorance but what brand engines are the Semroc engines?

Quote:

Originally Posted by CQBArms

Sorry for my ignorance but what brand engines are the Semroc engines?

They will be Semroc brand. We have been out of production for 36 years.

Ohhh very cool. I learn something new every day. If I might ask, all of these are going to be A-E? hobby motors? Also will there be the "chance" if hobby motors, to get some different colored smoke in either the boost or delay charge?

I'll go ahead and ask first. :D

What engine sizes are you looking to make (13mm, 18mm, 24mm, etc)?

Composite, BP, or both?

Core burners?

Will the emphesis be to fill gaps in existing motor lines or make a complete line?

Some motors that are no longer around that I really miss...

MPC 13mm B4 (awesome awesome little motor!)
Estes 18mm B4-6 (much better sustainer motor than the B6-6)
Estes 24mm D11-9 (another nice sutainer or min dia motor)
and of course......
Estes 18mm B14-anything :)

Here is a preliminary lineup of the sizes we are looking at:Engine Family Portrait This list is tentative and will be made more final over the next month so we can apply for EX-numbers. This is confidential, but your input is needed so we don't overlook something.

The propellant for all this batch is BP, but we are looking at "steam generators" later for contests.

The DECAP's will be a welcome addition for some. They will be available in 2-9 seconds in standard .5g load and -X with 1.2g load. A plugged version will be included as well as an Ejection Charge only version that takes standard igniters and will come in .5g, 1.2g, and 2.0g versions.

The order of release will be based on discussions here. The smaller 18mm and under machine is being built first. Engines over 70mm long or over 18mm in diameter will be done on the larger machine.

Too cool Carl!!!! I thought 29mm BP engines might be too much to ask for. The old Rocketflite 29mm's were a blast. This will make staging MPR a lot of fun!