Nice and neat, well done.
Cheers Colin.

Just to conclude this thread I finally retro fitted some holes in the bulkheads of my fast patrol boat today to install water cooling.

Below in one picture are the pin drills, reamers and the micro sander used to make some very neat holes for the tubing. I started small with a sharp 1.5mm drill in the pin drill to make the pilot holes. Next I enlarged the holes up to 3mm which allowed me to start using a step reamer which neatly enlarged the holes up to 6mm for the tubing. I highly recommend a set of step reamers if you don’t own some already, the small set shown in the picture were purchased on eBay quite cheaply, they cut holes well as they are very sharp. Finally my newly fabricated electric toothbrush (turned micro sander) tidied things up.

When using the small hand tools I found I needed to take my time, it also gave my fingers and thumbs a good work out. It is was worth it tho as I ended up with some very tidy holes in exactly the right places.😎

I would like to thank all those who contributed some great ideas and solutions to this thread.

ATB JT 😊

Thanks Doug. I'll have a look at the data.
Cheers Colin.

Ooops! Forgot the cable data sheet🤔
Well, it WAS late here!
Cheers, Doug 😎

Thanks Doug. I have spent the last few days with my grandchildren, building with lego. I'm home now so hopefully I'll be able to get on with the refit.
Cheers Colin.

Hi Colin,
Sorry to hear that🤔
My company flogged me to (almost) burn out at 65+.
Mainly to complete my Swan Song project; complete COMMS systems for the 7 new ships ordered by the Qatar Navy from the Fincantieri yard in Italy.
A project I'd worked on for over three years from concept to negotiations with navy and yard.
Nothing succeeds like success they say! 🤔🙄
Believe me, at the end I was happy to go and about a year later I turned down some consultant work. I read through the proposal and suddenly realised - I wasn't interested anymore! I WAS FREE!😊

Ref cables; it's 2.5mm² and good for 32Amps 😉 Type SILI-1V 2,5.
Data sheet attached. You can brush up on your German😁
BTW: The fuses fitted are the red 10A. If you reckon she'll drink more than 10A fit the yellow 20A fuses. Not sure now but I think I put a pair in your package!? Pesky memory!☹️
Glad to see I fitted the heat sink. I only have pics and video of the tests without it!
Cheers, Doug 😎

Still here but no boat construction recently, however here's my solution for drilling holes in bulkheads, note that some "bits" are made from screwdriver bits which are ground into drill bits, there is also an adaptor for the commonly available mini screwdriver sets /blades often screws end up in the most inaccessible places as I have found during the crash tender build, not everything can be planned. The main angle adaptor is driven by a cordless drill

Hi there Doug, I was put on the work scrapheap in 2005.
Medically retired due to health and safety issues with my arthritis.
Even though I was works manager and could have delegated any physical jobs.
As a protype engineer I found it hard to be so cruelly dumped. But it has given me the time for this lovely hobby.
And I'm still learning.
There is a piece of aluminium sticking out of the converter box.
Just a query Doug, what is the grade and rating of the wires you used as I need to extend.
Cheers Colin

Re - It was last reported that he has been seen with an accomplice Known as 'Lizard'.

Probably that ex G.O.T dragon,- breathes fire Martin😁 possibly used to heat the boat 'torchering' prong😂
JB

Re - You'll have to walk slowly to catch me.

Didn't someone say once, "Walk softly (and carry a big extinguisher) when in Hereford"?😁
JB

Re - Have you thought about putting a universal joint part way down then you could get a straighter angle.

Had thought of using one of the universals I have Martin (was going to use them in the ST but they were rubbish) but haven't needed to drill any more holes yet. One thought I had was, if you let go while drilling you'd be likely to have a nasty helicopter inside your boat😮, I thought the straight shaft was safer, (saw and apprentice lacerate his fingers years ago with a die grinder (didn't put the grinding bit fully in, got a right angle on the shaft and it was instant mincey fingers time)😭 Always kept that in mind😀.
JB

Thanks all for some great ideas.

JACOBS CHUCK

I liked Joes Jacobs Chucks Idea so much that I fabricated my own. 👍

See the picture below. The Chuck was originally fitted to a old Expo 12v miniature drill (Many years ago I replaced it with a bigger more versatile chuck). For the thumb turn knob I cut down a plastic glue spout, I also found some plastic pipe that had the right diameter to rotate the drill in while holding it in position. It’s great to make the old chuck useful once again turning it into a handy compact hand drill.

I will use the miniature drill to drill small pilot holes in the bulkheads. Once the pilot holes are drilled the holes will be enlarged to the correct diameter with a Step Reamer which should produce a nice neat hole. Thanks Robbob you gave me the idea of using a reamer 😎

MICRO ORBITAL SANDER. (see picture below)

Returning to the dental theme of my earlier Post (thanks to the idea on YouTube) I have repurposed this old electric toothbrush head into a miniature orbital sander. The sanding disk were easy to make with a hole punch. Velcro is also cut with the punch then glued with CA onto the back of the industrial abrasive paper disk.

If you fancy making one yourself don’t try cutting of the brush material, I found it easier to pull it out of the brush head with some pliers. A velcro hook disk can then be glued with CA onto the head.

I luckily have a old unused Braun toothbrush, but as another option you could always purchase a cheep battery powered alternative. 🤔

Should make it easy to sand in tight spaces.

JT 😊

"15 years ... retirement gift" !?
Hmm! Someone been tellin' porkies about their age eh Colin!😁

Ref water cooled ESC!
If you are still intending to run the Supermarine in your Commander, at max 12V SLA I assume, it shouldn't draw more than 10A or so.
So a 20 to 30Amp continuous rated ESC should cope with that without sweating.
More likely to get warm is the bridge rectifier in the converter board I made for it, which BTW is rated for 20A.
Remind me please! Did I bolt a chunk of alu to it?
If not and it gets hot - do it!😉
Cheers, Doug 😎

Now why didn't I think of that, I have one of those in my toolbox, never used it in 15 years. Part of a set given as a retirement gift from work.
I'll have to try it as my current project needs some holes in awkward places. As I'm retro fitting a water cooled esc. In my sea commander.
Cheers Colin.

Here's my solution for this problem, it's a flexible drive that I picked up at the London Model Show a few years ago. I can use hex drill bits or put a hex chuck on the end and use step drills as well.
I used it recently to make holes at low level through bulkheads of my Pilot Boat for the water cooling tubes. I will work even when bent 180 degrees 😀
Simples......

Sorry XC, we've drifted off topic😔
Hope you're not going to shoot us with your ivory handled Colt 45 M1872 General Patton Sir.
😁😎

"Great for drill and tapping small diameters. "
Great minds Joe👍😉
😎

It was last reported that he has been seen with an accomplice Known as 'Lizard'.

Martin555.

You'll have to walk slowly to catch me.
Cheers Colin.

Doug,
The little Jacob's chuck was such a bargain at $5 each that I bought several and used a Morse Taper 2 shank for my lathe tailstock. Great for drill and tapping small diameters.
Joe😎

Joe,
Now i see why you don't like to use power tools. LOL!!!

Martin555.

Doug,

I have been using those little razor saws as well lately. Last week one of them reminded me how sharp they are, a nice gash to the finger. They are sharp!
Joe🤕

Martin,
I agree, try all options.
Joe

Heartily agree Joe👍
I also use pin-vices and a mini 3 jaw chuck, a spare for my mini milling machine.
I also find small razor saw blades very useful for opening out and shaping the initial pilot hole in awkward places.
Cheers, Doug 😎

Is there a reward for information leading to his arrest. LOL!!

Martin555.

"then heat the tip till cherry red then gently press the hot end against the bulkheads ..."
WANTED!! HAVE YOU SEEN THIS MAN?
COLIN H; AKA 'THE HEREFORD PYROMANIAC'.
If seen DO NOT approach him but call Hereford Central Police on .....

😁😎

Hi Joe,
It is very rare that i use any power tools when making my models.

But when trying to drill holes in bulkheads when the deck is already stuck on you don't always have the room for the tool and fingers so it is anything goes at this point LOL!!

Martin555.

JT,

One more comment, over the past few years I have gotten away from thinking about power tools as the first solution to doing something. Now I focus more on hand tools first and a I find my build quality has improved. It easier to make a mistake when using a buzzsaw, sf o my hand tools are more forgiving and enjoyable to use as well.

I attached a photo of some of my pin vices that use, starting with the smallest first. I find that the hex head drill bits intended for power drills are very easy to hold in the fingers and twist. They are usually shorter than any pin vice.

My largest one is a Jaobs chuck with a 0.7mm to 6.5mm capacity. I bought several chucks off of ebay for less than $15usd. I made the handle from aluminum on my small lathe. Works great to get into areas that a power drill won't reach. I use it on wood, fiberglass, plastic and even metal.
Good luck with your drilling adventure.
Joe 😎

Colin,
Now that is one I haven't tried yet, a hot poker! Good idea but I'll have to match your courage first and keep a bucket of water handy. 😊😊
Joe 😎

As most of the models in my collection are ancient this problem is quite a challenge. One of the methods I have used is to get a metal skewer and bend it at an angle to suit the needs of the job, then heat the tip till cherry red then gently press the hot end against the bulkheads, most times it will go through without much effort, BUT BEWARE, YOU MAY GET A SMALL FIRE SO HAVE A WET CLOTH HANDY.
Cheers Colin.

JB,
You hit the nail on the head! I do the same, stay away from power tools and just use small pin vices. Start with 1mm and work my way up in size.... The round file trick is also used, in a reverse twist as you quickly learn.

Great write up. 👍👍👍
Joe

Hi Jb,
I like that idea.
Have you thought about putting a universal joint part way down then you could get a straighter angle.

Martin555,

It always seems to be the chuck that limits how shallow an angle you can use, so I use a 12" long piece of 4mm straight hard piano wire (like you might use on aircraft landing gear) with some teeth filed in the end of it. You just hold it as close as possible to the drilling end firmly between your thumb and forefinger, and run your drill slowly while slowly moving forward, and guiding it where you want the hole (use a leather glove if you don't have asbestos fingers😁) Start slowly and gently, and once the hole has started you can speed up. Works really well for a starter hole which you can then enlarge with needle files etc. May not be pretty but it can save chuck teeth ripping your work to bits.😁 Takes a bit of practice.

I have also used needle files and chainsaw files run in reverse in the drill for enlarging these holes as well. A tip for starting drills in wood so as not to run off, is to start the hole by drilling in reverse to make a countersink, then when that's deep enough, reverse the drill to the forward rotation. Works well on balsa, ply etc, - usually prevents chipping out the surface. You can even drill through ply and balsa completely in reverse which makes a slightly smaller hole. Drilling normally in balsa usually makes the hole larger than the drill used.
JB

Interestingly Ian Looking on eBay the Chinese dental drills, hoses and diamond bits are quite cheep. They run on just 30 psi.

This guy has modified one to run at home of his workshop compressor. 🤔

See video below 😎 JT

Could be a lot of expense to drill some holes unless you thought it would be useful for a lot of jobs. I think I would bodge it the best I could and make it look neat afterwards, but that may be just me! The thickness and type of ply would make a difference. Birch ply can be tough stuff but liteply would be easier to poke through.

Looking again at Martin's idea it seems to have distinct possibilities but would depend on availability of pulleys or the facility to make them.

It is galling when you realise you have to go back in and do something like this, but it happens.

Ian

Yes Ian very much like working through a letterbox. 😁

You got me thinking tho dentist work in very small spaces drilling precision holes with yes a right angle drill. Looking at their drills they seem to be pneumatically powered by compressed air. 😎 JT

I was reading a thread on another site and a chap described a situation like this as trying to wallpaper the front hall through the letterbox. No help I'm afraid but it made me chuckle!

Could you get a pin vice in with a short drill and make a pilot hole to be enlarged? I have done this type of job with a Permagrit type grinding tool with a Dremel right angle, but obviously in a bigger space. As Graham said, whatever you do it may not be very pretty but you could always stick overlays with a neater hole over any messy work.

Good luck,

Ian

Hi JT,
Just a suggestion.

If you can make a pulley wheel a very tight fit on the drill bit.
Make a drill support handle with a blind hole to take the drill bit.

Add a pulley to your drill then using an 'O' ring between the drill and drill bit you should be able to drill the hole.

The length of the drill bit can be cut down if required.

I hope this helps.

Martin555.

Hi Martin,

this is a problem that many boat modellers must face. In my case I am planning to make 4 holes of approx 4mm dia for the water cooling silicon tubing. The cabin is just over 12cm long and the holes will be drilled 9cm down just above the floor the cabin.

JT 👍

I have also struggled with this when refurbishing my Crash Tender. I’ll be very interested to hear any workable solutions.

On a new build, hopefully you can plan ahead and put in any holes before the hull is assembled, plus a few spares, but that isn’t possible with a refurbishment.

I have had to drill holes at the best angle I could get at and then enlarge them and square them up with a file. Difficult and not very satisfactory.

Graham93

Can you post a photo of the situation.
And what size holes ?
What is the distance that has to be reached?
How much room do you have to get anything in?

Martin555.