rcktnut
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Yes they are!! Get rid of any burrs you might have after drilling. They'll bite you otherwise.
D12 Blast Destroyed My Flower Pot Blast Deflector
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As I like to think while I'm doing the job, the skin you save by deburring your edges is likely to be your own.
Put the blast deflector ON TOP of the adeptor. Not only does it fit, but it keeps the adeptor from deteriorating from the blast and corrosive BP residue.
Hans.
Notice that I just “liked” this post and did not also reply to it and say, “Oh my God, I am so dumb”. Oops. ;-)
Been there, done that. Hate wearing the T-shirt...
Well, if you want to see REALLY stupid tripod errors, look at this photo. I didn't realize that the tripod legs could be spread out wider. So I launched a fairly large rocket on an F52 with the tripod base too narrow. The rocket flew fine, but the blast from that F52 knocked the tripod over. This was on video, the tripod didn't even start tipping until the rocket was some 5 feet above the rod.
Hans,
Double blast deflector on that pad! Nice!
Can't remember why I did that..... ????
I put a clothes pin on the rod to hold the rocket up and off of the blast deflector. That only works with light to medium weight rockets. Maybe your second, smaller blast deflector was something expendable like that?
I also don’t like putting the rocket all the way down the rod onto the blast deflector as I fear the deflected flame will scorch the bottom of the rocket and the fins
Looks like another vote for my pad design!
What do you make the top plates out of?
What holds the rod in an upright position?
You must divulge your secrets! ;-)
The top plates are just a good 1/4" plywood, hole to suit.
For the rod, I put the thing on my drill press and used a Forstner bit to make a flat bottom hole about an inch down the 45° ramp.
The bit leaves a center mark and you use that to drill through to suit a "metal threads in wood" T nut. Pound that in, thread the end of your rod and thread a nut on to it. Thread the rod into the "T" nut and tighten the jam nut to hold everything nice and tight.
For a 1/8 rod, I think they are 10-24 threads and nuts. And that reminds me: I need to steel wool and wax that rod, that's nasty looking!
It's more trouble to build, to be sure, but it has a long history in the family and we like it.
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Those super cheap sets are usually dubious in the hss used and if you look at the sharpening angles on the tips they are all over the place. They are titanium coated hss drills by the very minimum of not being sued......
Of course you might have found a good set....
I'm still using most of the same drill bits I got in a Dormer jobber drill set in 1985..... ( a jobber drill bit is slightly shorter and less likely to break). Sign up to the engineering suppliers catalog and wait till a reasonable set is on special.
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I've bought some of these supposed high end drill bits. They are not industrial quality, but for a hobbyist, they are OK. Expect better than average, be pleased if they are better than that.
Hans.
If you're drilling a hole in wood they'll be fine. But I wouldn't expect great results in stainless. And you should be able to make a hole in wood with a rusty nail in your drill chuck. Usually.....
Don't know about that. I bought a pair of 1/8" el cheapo cobalt bits and drilled nearly 1000 holes through 1/8" mild steel to attached some body panels on a kit car. They work fine.
Hans.
I am waiting for my el cheapo cobalt bits to arrive on Tuesday.
COMOWARE Cobalt Drill Bit Set- 13Pcs M35 High Speed Steel, Twist Jobber Length for Metal, Cast Iron and Wood Plastic with Metal Indexed Storage Case, 1/16"-1/4" https://a.co/d/2wds8J7
I find, however, that one can simply punch a hole in the bottom of the bowl with a nail and a hammer.
I need to remember KISS: Keep it simple, stupid
I overthink everything.
SharkWhisperer
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To be nitpicky, that's smokeless (NC +/-NG) not blackpowder, and a .22LR takes (maximally) 2 grains, not grams. Typical loads top out around 1.5 grains, or around 0.1 grams, not 2 grams.
That said, a 30 grain (2 gram) BP load in a musket is considered pretty light. And a D12 contains >24g BP and that's not trivial--your point stands.
Ok. The replacement flower pot (plus a washer and a nut) did the trick as a blast deflector today.
The stainless steel bowl with 1/8” hole and the (steel?) black olives can with 3/16” hole are backups.
The stainless steel bowl with 1/8” hole and the (steel?) black olives can with 3/16” hole are backups.
Ok, cool, but drilling is boring.
I am waiting for my el cheapo cobalt bits to arrive on Tuesday.
COMOWARE Cobalt Drill Bit Set- 13Pcs M35 High Speed Steel, Twist Jobber Length for Metal, Cast Iron and Wood Plastic with Metal Indexed Storage Case, 1/16"-1/4" https://a.co/d/2wds8J7
I find, however, that one can simply punch a hole in the bottom of the bowl with a nail and a hammer.
I need to remember KISS: Keep it simple, stupid
I overthink everything.
Unboxing the cobalt drill bits.
Nicely packed in metal case. Not bad for $11.99.
Is there any way to tell if they are really cobalt drill bits?
I just hammered a hole into the bowl and can using a hammer and a couple of pointy wood screws of the correct diameter.
. But I now have a set of fancy cobalt drill bits to show off. .
Like this?
Seems wobbly. I think it is just a cheap tripod.
There we go. Big blast deflector.
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Cobalt drill bits are good but brittle. They are best used in a drill press where the load put on them is vertical. In hand drills, it's difficult to not put a side load due to the handle being off center. This usually causes them to break more frequently in hand held drills.
They look to be reasonably ground.
My tripod's legs are able to spread out horizontally, making a very stable platform. Handles G64 well.
Hans.
I need a better tripod.
goose_in_co
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Are all of the adjustment points for the head tight?
Did you separate the legs once they were extended?
I see that the tripod has a spreader bar at the end of the first section, Try only extending the upper leg, and not the upper and lower leg sections, that will make it more stable as well.
Goose
Don’t feel too bad. SpaceX had a similar problem.
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