Anyone ever built a pad made completely of 1515 extrusions? SomeThing like: https://www.jcrocket.com/prorailbase.shtml
Chuck
Chuck
Design wanted: 1515 pad
- Thread starter cwbullet
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Chuck,
Have you seen this one?
https://www.vernk.com/Construction/8020_pad/TRF_8020_Pad_ArchivedPage.htm
Have you seen this one?
https://www.vernk.com/Construction/8020_pad/TRF_8020_Pad_ArchivedPage.htm
Yes. It is ok, but I am thinking of a pad that sits on the ground without legs. This might allow it to take level 3 birds better.
Both work for me.
xenon
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Snapped the legs off one of those with an M2250 once.
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My ProRail base isn't all 1515 channel, but might provide some inspiration.
That is why I am looking for something with less of a fulcrum to snap.
bobkrech
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John's design, or variants thereof, are the stiffest lightweight, L3 launcher design, and are only surpassed by a full-blown tower.
If you implement a 15/15 (or 10/10 or 10/x0 or 15/x0 launcher design, you can purchase accessory plates from 80/20 or fabricate your own. If you fabricate your own, I strongly suggest you get all the aluminum parts Type 2 anodized (pick your color or clear) in one batch. The batch cost will be between $50-$100 depending on where you live and your negotiating skills. Just make sure you have done all the machining ahead of time and the you add 6 mils for clearances as each surface will grow ~ 1.5 mils (a drilled or tapped hole will shrink by ~3 mils ID and an round part will expand by about 3 mils OD.) so you don't want or need to have overly tight fits/clearances.
The on-line 80/20 catalog is huge. Spend time reading and understanding the system. Additionally if you make a sketch of your design and send it to the local 80/20 distributor, they will generate a detailed mechanical drawing with all suggested components, a detailed parts list and a quotation, and you can iterate several times to get what you need.
My local 80/20 distributor will cut all parts, assemble it and deliver it to me for 50% above the parts costs. This is really a good deal, especially if you do not live close to the dealer.
The base can either be a T or a Y design. If you use a T you can put wheels on the cross-piece and a hitch on the other end and pull it with an ATV or a person. One would usually have outriggers that Y off the short ends of the T to make a triangle for stability. If there is a 4' high vertical post at intersection of the 3 legs and another 3' vertical post at the other end of the T or Y, you can add a 12 volt DC winch to erect and lower the launch rod making a mini-tower. (Harbor Freight has a $59 dollar unit (sale price) that works well.
The Y or T components may be constructed with 10/x0 or 15/x0 components with the longer side in the vertical direction to make it significantly stiffer.
Do not have aluminum in direct contact with copper or brass . If possible use stainless steel screws, bolts, washers and nuts or if you can't use black oxide or plated steel fasteners. Do not use brass or copper screws, bolts, washers or nuts because it makes a battery and causes corrosion.
Find a local 80/20 supplier, or go to Grainger, Tractor Supply or other industrial supply house to get a quote for you aluminum extrusions and other parts and compare it to the on-line prices. Shipping long parts is expensive and there are no shipping charges from your local supply house even if they have to special order the parts. If you order your parts on-line, order all the parts at once to get the lowest shipping costs. Plan ahead and specify lowest cost delivery. This may take up to a week or 2 but it may be substantially cheaper than UPS or FEDEX ground.
You will want height adjusters the 3 arms. On the long arm use a trailer leveler post. You could probably use these on the 2 shorter legs as well. You also want to make provision to stake the arms to the ground which will greatly increase the launch weight capacity.
You could eaxily spend $500 to $1000 for a really nice 80/20 launcher, but if you design it right it will be easy to use and will launch 200+ pound rockets if made with the proper sized components.
Bob
If you implement a 15/15 (or 10/10 or 10/x0 or 15/x0 launcher design, you can purchase accessory plates from 80/20 or fabricate your own. If you fabricate your own, I strongly suggest you get all the aluminum parts Type 2 anodized (pick your color or clear) in one batch. The batch cost will be between $50-$100 depending on where you live and your negotiating skills. Just make sure you have done all the machining ahead of time and the you add 6 mils for clearances as each surface will grow ~ 1.5 mils (a drilled or tapped hole will shrink by ~3 mils ID and an round part will expand by about 3 mils OD.) so you don't want or need to have overly tight fits/clearances.
The on-line 80/20 catalog is huge. Spend time reading and understanding the system. Additionally if you make a sketch of your design and send it to the local 80/20 distributor, they will generate a detailed mechanical drawing with all suggested components, a detailed parts list and a quotation, and you can iterate several times to get what you need.
My local 80/20 distributor will cut all parts, assemble it and deliver it to me for 50% above the parts costs. This is really a good deal, especially if you do not live close to the dealer.
The base can either be a T or a Y design. If you use a T you can put wheels on the cross-piece and a hitch on the other end and pull it with an ATV or a person. One would usually have outriggers that Y off the short ends of the T to make a triangle for stability. If there is a 4' high vertical post at intersection of the 3 legs and another 3' vertical post at the other end of the T or Y, you can add a 12 volt DC winch to erect and lower the launch rod making a mini-tower. (Harbor Freight has a $59 dollar unit (sale price) that works well.
The Y or T components may be constructed with 10/x0 or 15/x0 components with the longer side in the vertical direction to make it significantly stiffer.
Do not have aluminum in direct contact with copper or brass . If possible use stainless steel screws, bolts, washers and nuts or if you can't use black oxide or plated steel fasteners. Do not use brass or copper screws, bolts, washers or nuts because it makes a battery and causes corrosion.
Find a local 80/20 supplier, or go to Grainger, Tractor Supply or other industrial supply house to get a quote for you aluminum extrusions and other parts and compare it to the on-line prices. Shipping long parts is expensive and there are no shipping charges from your local supply house even if they have to special order the parts. If you order your parts on-line, order all the parts at once to get the lowest shipping costs. Plan ahead and specify lowest cost delivery. This may take up to a week or 2 but it may be substantially cheaper than UPS or FEDEX ground.
You will want height adjusters the 3 arms. On the long arm use a trailer leveler post. You could probably use these on the 2 shorter legs as well. You also want to make provision to stake the arms to the ground which will greatly increase the launch weight capacity.
You could eaxily spend $500 to $1000 for a really nice 80/20 launcher, but if you design it right it will be easy to use and will launch 200+ pound rockets if made with the proper sized components.
Bob
Here's some pics of our 1010 pads, but we have 1515 pads built the same way.
The issue is how long the rail is and how much flex you get. It isn't rod whip, but it's not as steady with large rockets as a 4lb rocket on the 1010 pad.
A stiffer blast shield would probably help a lot since that is the brace for the rail or braces between the base and the twin verticals that hold the rail might stiffen things too.
BTW, this pad is about 7 years old and has spent the whole season (Oct to June) sitting out in the field. They are stored outside in the off season too. Very durable!
The issue is how long the rail is and how much flex you get. It isn't rod whip, but it's not as steady with large rockets as a 4lb rocket on the 1010 pad.
A stiffer blast shield would probably help a lot since that is the brace for the rail or braces between the base and the twin verticals that hold the rail might stiffen things too.
BTW, this pad is about 7 years old and has spent the whole season (Oct to June) sitting out in the field. They are stored outside in the off season too. Very durable!
Handeman,
How did you make the blast deflector?
How did you make the blast deflector?
Do you have any pictures in the loading position?
There are two pins which hold the rail in the vertical position. You remove the top pin and the rail pivots down to rest on back up right support. The rocket is loaded from this position. The rail is then brought to the vertical and the top pin reinserted.
This might help
https://www.rocketbattle.org/photos2015/108.html
Ben
Ben
This might help
https://www.rocketbattle.org/photos2015/108.html
Ben
Ben
Thanks. How long are you rails?
