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Revision as of 19:22, 12 May 2008 by Frank (talk | contribs) (New Drills)
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Current Club Drill

Location Currently the old Bosch drills and batteries are at my house (Frank) in Bristol, Generally so as they can be tested and generally fettled.

Drills Two of the drills are not hitting very hard and are taking lots of current, this may be due to previous fettling of the hammer action component. Rumour has it they are somewhat intolerant of the wrong amount of grease in this component. I have sent an email to a contact Wookey gave me regarding sorting this. So watch this space. However does anyone know about this or know a man who does?

This weekend I should have a better idea of the status of all these drills.

Batteries Last year I made three new batteries for the drills using NiCad’s. Only two survive now... These should be OK, mainly because they have not been used a lot. I also have a fair number of NiCad ‘D’ 4Ah cells they were free, I was going to fettle two packs of these to see how they last. (They’re not designed for power applications so I suspect will not live long)

The batteries I have will be fettled with the drills.

We probably do not need additional battery packs for the old Bosch drills, especially as we have two new reliable drills.

Battery chargers base camp We have two mains chargers for base camp . One is an old Bosch charger, the other is a trickel charger.

Battery chargers top camp Last year after the demise of first battery I used my lamp trickel charger to regulate the battery charging current, This works but uses two solar panels in series to get the 24V. It is therefore not much use in the dark. (It means I can charge my lamp batteries overnight then)

With the new drills we may not need any more than this?

New Drills

Makita are very kindly giving us 2 new BHR180 rotary hammer drills. These use 18V battery packs:

Modifications

  • Do we want to mod them so battery packs aren't attached to the drill but can stay in a tacklesack?
    • As the drills use lightweight Li-Ion packs, there may be little advantage in shifting the battery packs from the drill to a tacklesack. Apparently the drill+battery weighs 3kg, compared with around 4kg for a Bosch GBH24VRE. Duncan.collis 14:06, 9 May 2008 (BST)
    • Looking at a picture of these drills, it appears that most of the weight of the machine is out in front, with the battery pack directly below the handle. The battery in this position may provide some balance to the drill, preventing it from being too front-heavy. Duncan.collis 14:06, 9 May 2008 (BST)

Tackel sacs for the new drills

  • We need to make some padded tacklesacks for transporting them underground.
    • The main purpose of padding is to protect the dry bag the drill is in. First choose good tacklesacks that don't have holes in them! Use some old karrimat, foam floor tiles or knackered wetsuit to make the packing. Pad both inside and outside the drybag. Duncan.collis 14:06, 9 May 2008 (BST)

Charging of the new drills

  • Someone needs to contact Makita to see if they make a car charger for their 18V LiIon cells. They do make a car charger for NiMH/NiCad (DC1822) This will not work.
    • Probably best if the same contact is used as with the sponsorship. It would definatly be worth 'buying' a car charger. --Frank 20:22, 12 May 2008 (BST)
  • The next best option is to use a mains charger with the inverter at top camp.
  • Charging: am I right in thinking solar panels at top camp can only charge 12V or 24V? We can either try to make a transforer, bring a mains adaptor up, or take battery packs down to basecamp for charging. Thoughts?
    • If you're using the manufacturer's Li-Ion packs, it goes without saying that you shouldn't try charging them on a home-made charger unless it was designed for the purpose by someone who knew what they were doing. Duncan.collis 14:06, 9 May 2008 (BST)

Note: The new Drill batteries cannot be charged with the Bosch drill chargers. LiIon cells can be harder to charge than NiMH, they are much less tollerant of overcharging. --Frank 20:22, 12 May 2008 (BST)

Aditional batteries

  • We can make spare battery packs using some cells from gp batteries?
    • It is probably not a good idea to modify the existing drills/batteries this year, we want to run them as is for as long as possible. --Frank 20:22, 12 May 2008 (BST)
    • The batteries should be as far as possible be of the same technology as the drill batteries. Because in the future confusion will cause the chargers to be mixed up and problems will occur. --Frank 20:22, 12 May 2008 (BST)


Use of the inverter at top camp We do have an inverter at top camp. These items are very inefficient and we do have very limited power. The danger of mains at top camp is the main issue, getting a 240V electric shock is a numbers game, 19 times out of 20 you will get away with it.

Try not to bring lamp battery chargers that need to use the mains. For most all lamps there are 12V chargers that will work off the battery directly. The same goes for mobile phone chargers.

    • Think very carefully about the safety issues surrounding the use of an inverter to provide mains at the bivi. Duncan.collis 14:06, 9 May 2008 (BST)
    • As part of the Bivi fettling this year I was intending to move teh battery and gubbins into the Bivi, Not being in the rain/Sun will make it safer but a mains inverter is very dangerous in the damp!!!


Drill Bits Do we need some new drill bits?