And now for something completely different...

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jd2cylman

TRF Supporter
Here's a blast plate for you. A little pricey. ~ $150.00 I looked for 36" blades, but they're all notched. Don't think you'd like that. lots of sharp edges... SMR SMR Entropy Demonstrator Here's a blast plate for you. A little pricey. ~$150.00 I looked for 36" blades, but they're all notched. Don't think you'd like that. lots of sharp edges...
Thanks, a good find... and free shipping for every order over \$2,000.00. Gonna have to coordinate a group order to qualify.

Actually, I think stainless heat diffusers for induction cooktops might work... only they are a little small at 9" to 11" diameter. Ceramic tiles can take quite a bit of heat and come in a variety of larger sizes. I'm planning to have it swing up with the truss, so something maybe 14" to 16" would be ideal.

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teepot

Well-Known Member
TRF Supporter
How about an AR 500 rifle gong. They can be up to1/2" thick and come in a lot of sizes. Not pricy either.

SMR

Entropy Demonstrator
How about an AR 500 rifle gong. They can be up to1/2" thick and come in a lot of sizes. Not pricy either.
Ooooooh... hadn't thought of that but a really good idea. Wouldn't even have to be a new one - can repurpose one after its productive life on the range is spent. Will keep my eyes open for one on Craigslist, preferably a larger size. Thanks.

edit... found this one, but 1 1/4" thick, too heavy for me

A used tillage blade is also an option... hey, they wear out, don't they? Or, next time our farmer leaves his equipment in the field...

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jd2cylman

Still not Carl... ;-)
TRF Supporter
Ooooooh... hadn't thought of that but a really good idea. Wouldn't even have to be a new one - can repurpose one after its productive life on the range is spent. Will keep my eyes open for one on Craigslist, preferably a larger size. Thanks.

edit... found this one, but 1 1/4" thick, too heavy for me

A used tillage blade is also an option... hey, they wear out, don't they? Or, next time our farmer leaves his equipment in the field...
My brother just changed out a bunch, but the reason he changed them is because they wear smaller. I can get one for you, but it’s just about 19”. Flat ones are ~17”. Lemme know. Price is right on them (free). I can bring one tomorrow to QCRC if you get ahold of me tonight

SMR

Entropy Demonstrator
Currently just using a 5/16" bolt to lock the legs in their full forward position, may eventually drill these holes out and use a 1/2" bolt with a wing nut.
Did that today... drilled out the holes on both legs and corresponding stop brackets. They line up perfectly for the 1/2"-13 NC bolts and wing nuts. Using the K.I.S.S. principle, just one easy to install bolt to hold each leg in the 120° position. All drilling and welding on base complete. Ready for cleanup, paint, and decals.

SMR

Entropy Demonstrator
Taking advantage of the warm weather for final paint and photo op. Truss leaning forward slightly because tires not removed, which lowers back end about 6" and brings truss to vertical.

Outstanding work

SMR

dpower

Well-Known Member
That's a work of art, Sather! And looks darn functional too.

SMR

Handeman

Well-Known Member
TRF Supporter
Taking advantage of the warm weather for final paint and photo op. Truss leaning forward slightly because tires not removed, which lowers back end about 6" and brings truss to vertical.

View attachment 467279
How do you adjust the angle of the launch rod to make sure it's away from the flight line and/or up wind?

SMR

SMR

Entropy Demonstrator
How do you adjust the angle of the launch rod to make sure it's away from the flight line and/or up wind?
A few options there, still in the wishy-washy phase..

1) Since the pad gets put in the dirt and I want to keep it from getting muddy (yeah, I know, right?), I plan to follow the time honored midwest tradition of placing boards under the feet. Thicker boards in conjunction with thin ones on opposite feet give "shim" options.

2) Still evaluating adding the Bulldog jacks. This will also help in setup and moving, as I let the weight get a bit on the high side and lifting it to pull off the tires is getting to be an issue.

3) I have a few ideas for a simple adjustable mechanism between the pad bottom and the truss bottom. But I have also seen a lot of big pads that don't have windage adjustments at all.

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SMR

Entropy Demonstrator
I worried about drilling holes in the truss, as getting them exactly straight on the first try was a requirement. I found from the 1010 rail inside my Patriot battery that it is possible to force a slight curve along the length of a rail with bolts a little bit out of alignment. It probably wouldn't matter with just 2 buttons, but I often use 3 to optimize usable rail length (bottom two are close) and minimize torque on them induced from side wind (top one is as high as I can make it). Luckily, I found this tool to help. The bottom is a vee, so it self aligns on a curved surface. Has a bunch of tall holes to keep bits of various sizes aligned perpendicular to the tube. Voila! The top and bottom holes were already present, 3 holes spaced equally between them are added along a chalk line snapped on the masking tape. Using 5/16" stainless carriage bolts in the rail, extending through the tube and secured with locknuts on the backside. Working alone made it difficult to get all 5 bolts aligned to drop in simultaneously, so I ended up using a jack stand to hold one end of the rail up, dropping it one notch at a time was just about perfect to get the bolts in individually. And finally, nothing finished without a test fit - a 5.5" / 54mm Seahawk booster... first rocket to officially use the pad!

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SMR

Entropy Demonstrator
There is a certain amount of danger working with and around something like this, such as the fear that folding metal pieces function as scissors, and one of the obligations as a designer / builder is to minimize the risk AND to placard what should be obvious dangers to others. (Thank you, tort law). Here is one that literally caught me by surprise… when working around the front side of the pad (taking off the hitch, locking the legs forward, etc) with the truss in place, the 90° outside corner of the up-lock bracket really, really hurts when you stand up too quickly. Luckily it stabbed me in the shoulder instead of my cranium. So, while I had it off to paint, I took the opportunity to cut off the corners. And paint it a bright color.

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SMR

Entropy Demonstrator
Happy Father's Day!

Up-lock bracket installed. Added a "coupler grip" as a grab handle, which coincidentally had the right size and spaced holes, so it fit on the existing U-bolts, which have yet to be cut to length.