Drill Press Motor Mounting

[Nick PassmoreParticipant @nickpassmore75850]

I have a Record drill press that I bought about 25 years ago. Its motor is mounted on a plate that has two steel rods that slide in holes in the back of the head casting. The motor sticks out quite a long way at the back which means the whole thing has to be positioned further from the wall than I would like and there is no lever to take the tension off the belt to change speed so I have to get a clamp and use it to pull the motor and its mounting plate towards the head casting.

 

I was wondering whether I could instead mount the motor to one side by bolting a fixed plate at the back of the head casting sticking out to the side of the head then attaching the motor in front of that and whether, instead of the old v belt, using stretchy round-section polyurethane belting would give enough play to change speeds without being so loose it would slip. I think 8mm round belt would fit the existing pulleys.

 

What are my chances?

Edited By Nick Passmore on 29/07/2018 16:49:24

[Nick PassmoreParticipant @nickpassmore75850]

[richardandtracyParticipant @richardandtracy]

Thinking of the contact areas of a round belt compared to a V belt and the liklihood of slippage. Gut feel would suggest it'll take about 1/4 the torque. At the higher speeds it should do, but at the low speed range of the press it's possible/probable it'll struggle.

Just my initial reaction.

Richard.

 

Edited By richardandtracy on 29/07/2018 16:55:29

[BazyleParticipant @bazyle]

How about a couple of hinge pins in one side of the existing plate – the sort that have a treaded mount and a pin at 90 degrees. Then the corresponding loop part of the hinge in a pair of the motor holes that will get your motor at the front side as you require. Then some system to apply the belt tension by pushing between the motor and drill body.

[Clive FosterParticipant @clivefoster55965]

Nick

Did a similar thing many years ago, albeit on a line-shaft drive drill rather than a modern type like your Record. Worked well enough, despite Mk 1 imperfections, that I never bothered to sort the niggles.

I used my favourite thick rubber hose in steel pipe controlled stiffness vibration reduction pivot system which works very well indeed but takes bit of making if you don't have there requisite parts in the handy box. Needs welding too.

These days would probably use ball bearing hinges which can now be got for reasonable prices. Ordinary butt hinges are slack and, usually, rattle when used as pivots. For example **LINK** . They can be found cheaper and there are other less costly breeds. Needing similar for another job I lucked into a bunch of those lightly used at around £2.50 a pair which is why I know they re pretty good.

I made a cam thingy with screw adjustment so I could slacken off the belt. Probably about a zillion was to make one. I simply filed a couple of groves about 90° apart in a 3/4" thick disk, drilled it off centre, screwed a rod as an actuation handle and arranged a blunt pointed setting screw to locate in the grooves at tight and slack positions. Not wonderful but worked well enough provided I pushed the motor back a bit to make clearance when turning the cam. Maybe 1/2" throw on the cam multiplying to a "long inch" at the motor shaft due to the cam being closer to the pivots than the motor shaft.

Stick with the Vee belt. Probably best to knock up some sort of cover. Whatever you do it won't be pretty.

Alternative if you have headroom is to invert the motor and move it forwards a bit. Flat vertical plate or angle iron frame fixed to the sliding bar holes will probably put motor centre line more or less over the pillar. Similar pivots, cam et al. Need a new belt tho'. Can probably be made to look quite factory if you make an effort.

Clive

Edited By Clive Foster on 29/07/2018 17:28:38

[Nick PassmoreParticipant @nickpassmore75850]

Thanks very much for these replies. The ball bearing hinges in particular seem like a possibility.

Nick

[larry phelan 1Participant @larryphelan1]

I am surprised that the motor projects so far,what is the reason for that ?. Most of the drills I have seen have the motor mounted just behind the column so that only the dia of the motor is the distance to the wall,and for a 1/2 or 3/4 HP motor,this would not be much. How close to the wall do you need to get ?

My Chinese 16mm floor drill has a fair sized 1/2 HP motor fitted and Chinese motors are not too small,but it still fits close enough to the wall. Also,very little movement is required to change the belts.

[SillyOldDufferModerator @sillyoldduffer]

Posted by Nick Passmore on 29/07/2018 16:48:28:

…

 

I was wondering whether I could instead mount the motor to one side by bolting a fixed plate at the back of the head casting sticking out to the side of the head then attaching the motor in front …

Thing to keep an eye on is the balance. The front/back arrangement counterbalances the weight of the motor on top of the pillar with the base, making the drill more stable.

Good balance might only matter when the drill isn't bolted down, i.e. when it's more likely to topple over, except mounting an unbalanced motor might also cause vibration whilst drilling. That could be reduced by putting another weight opposite the motor. Unfortunately that would make the drill top-heavy, to be fixed with more weight on the base.

I'm sure it could be done, but might be more trouble than expected.

Dave

 

Edited By SillyOldDuffer on 31/07/2018 14:53:18

[larry phelan 1Participant @larryphelan1]

Just a thought,how about setting the machine at an angle to to the wall ?

[JohnFParticipant @johnf59703]

Hi Nick, I too did a conversion on a line shaft machine something close to 50 years back and used a cam arrangement for belt tension, I sold the machine only about a year ago but if you message me your email I can sent some photos – maybe they will be of use ?

However what I would suggest is have the existing plate as close as possible to the machine casting when fitted. To make a belt tension I would add another plate with a pivot – so its like a very large hinge then add a cam arrangement at the opening side of the hinge so you can change speeds easily. You may need a new belt to do this.

If a sketch would help let me know.

John

[Nick PassmoreParticipant @nickpassmore75850]

Larry, I reckon I would be able to move the whole thing back about 7in. I agree that’s not a huge amount but in a crowded workshop it would be welcome. Putting it at angle in my particular circumstances would take up even more room!

Dave, good point about balance. The thing does have a very solid base and is well bolted down but vibration might be another matter . . . .

John, thanks for the offer, I’d love to see the pics. I was actually wondering today about a separate idler pulley to tension the belt.

Nick

[Clive FosterParticipant @clivefoster55965]

Nick

If contemplating a separate idler pulley its well worth looking into re-purposing the self contained spring loaded devices used on car auxiliary drive belt systems. Its hard to match the engineering quality for the sort of prices they can frequently be found for. Probably need to add some form of screw stop to set the tension appropriately and make arrangements or modifications to cover the full range of belt positions.

Clive.

[Nick PassmoreParticipant @nickpassmore75850]

Clive.

Thanks for the suggestion. There seems to be a good selection of these things on Ebay and some look as if they would be relatively easy to mount.

Nick

[Brian WoodParticipant @brianwood45127]

Nick,

Just a further thought prompted by Larry Phelan; Can you mount the drill in a corner? I solved a similar motor to wall conflict with my Dore Westbury mill in two different installations that way

Regards

Brian

[Clive FosterParticipant @clivefoster55965]

I found "drill in a corner" awfully restrictive in my first shed. Unlike a mill where you are generally dealing with things small enough to fit on the table its often necessary to handle long parts on a drill. Usually house / garden DIY related but still essential.

When I built my new workshop I made sure that the second door was positioned so that minor shifting of the Bridgeport mill let long stuff poke outside over the veggie plot. The drill is more or less in the middle of the 16 ft wide workshop but also arranged so it can be aligned with the door for really long stuff. A 20 ft long job had me head scratching. Helped by that years crop rotation put all the tall plants out of the way!

A turning job on 2.5 m long stock planned for next month looks like being "interesting tho'.

Clive.

[Brian WoodParticipant @brianwood45127]

Yes Clive, you are quite right, drills need space either side, but I have little idea how Nick is fixed for space and offered the idea for him to consider.

Good luck with your long turning job; it will test your imagination if nothing else.

Regards Brian

[Nick PassmoreParticipant @nickpassmore75850]

Thanks again for these suggestions. I did actually try moving the drill press into a corner — like Clive I find there are enough occasions when I need to drill a hole halfway along, for instance, a long wooden batten that it wasn't really workable.

And as for turning something 2.5m long, a second door would be a start, a larger garden might be needed too!

 

Nick

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